23022_Chapel Hill Police Property_RARpt_20211007

Risk Assessment Report
828 Martin Luther King Jr. Blvd. Property
Chapel Hill, North Carolina
IHSB Site No. NONCD0001486
Brownfields Project No. 21061-17-060
H&H Job No. TCH-009
October 7, 2021
C-1269 Engineering
#C-245 Geology
-1411
hart hickman
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SMARTER ENVIRONMENTAL SOLUTIONS
2923 South Tryon Street, Suite 100 3921 Sunset Ridge Rd, Suite 301
Charlotte, NC 28203 Raleigh, NC 27607 www.fiarthickman.com
704.586.0007 main 919,847.4241 main

Risk Assessment Report
828 Martin Luther King Jr. Blvd. Property
Chapel Hill, North Carolina
H&H Job No. TCH-009
Table of Contents
Section Pale No.
1.0 Introduction..............................................................................................................................1
2.0 Site Background Information.................................................................................................3
2.1 Site Location and Surrounding Land Use..............................................................................3
2.2 Site Description......................................................................................................................3
2.3 Site History.............................................................................................................................4
2.3.1 Site Ownership and Operational History.........................................................................4
2.3.2 Previous Environmental Investigations............................................................................4
3.0 Environmental Setting.............................................................................................................7
3.1 Site Topography.....................................................................................................................7
3.2 Surface Water Hydrology.......................................................................................................7
3.3 Geology..................................................................................................................................8
3.4 Hydrogeology.........................................................................................................................9
4.0 Summary of Environmental Conditions..............................................................................11
4.1 Background Conditions........................................................................................................11
4.2 Extent of CCPs.....................................................................................................................12
4.3 Soil and CCP Concentrations...............................................................................................12
4.4 Groundwater.........................................................................................................................13
4.5 Surface Water.......................................................................................................................13
4.6 Stream Sediment...................................................................................................................14
5.0 Human -Health Risk Assessment..........................................................................................15
5.1 Exposure Pathways Evaluation............................................................................................15
5.2 Exposure Unit Designations.................................................................................................18
5.3 Exposure Point Concentrations............................................................................................19
5.4 Exposure Parameters............................................................................................................20
5.5 Toxicity Factors....................................................................................................................21
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5.6 Risk Assessment Results......................................................................................................22
5.6.1 Exposure Unit #1— Upper Level...................................................................................23
5.6.2 Exposure Unit #2 — Lower Level...................................................................................24
5.6.3 Exposure Unit #3 - Embankment...................................................................................24
6.0 Ecological Risk Assessment...................................................................................................26
6.1 Exposure Units.....................................................................................................................26
6.2 Exposure Point Concentrations............................................................................................27
6.3 Ecological Screening Evaluation..........................................................................................28
6.3.1 Soil Ecological Screening..............................................................................................28
6.3.2 Stream Sediment Ecological Screening
.........................................................................30
6.3.3 Surface Water Ecological Screening..............................................................................31
7.0 Conclusions and Recommendations.....................................................................................32
8.0 References...............................................................................................................................35
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T :,4- _T Ir-I l-
Table 1 Summary of Human Health Risk Assessment Results
Table 2 Soil Ecological Screening Table
Table 3 Stream Sediment Ecological Screening Table
Table 4 Surface Water Ecological Screening Table
List of Figures
Figure 1 Site Location Map
Figure 2 Site Map
Figure 3 Sample Location and Exposure Unit Map
Figure 4A Residential Human Health Risk Drivers Map
Figure 4B Construction Worker Human Health Risk Drivers Map
Figure 5 Ecological Risk Drivers Map
List of Appendices
Appendix A Historical Data Tables and Figures
Appendix B Summary of Background Screening Values Calculations
Appendix C DEQ Risk Calculator Documentation
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Risk Assessment Report
828 Martin Luther King Jr. Blvd. Property
Chapel Hill, North Carolina
H&H Job No. TCH-009
1.0 Introduction
This Risk Assessment Report has been prepared by Hart & Hickman, P.C. (H&H) to document
the results of human health and ecological risk assessment activities completed for the property
located at 828 Martin Luther King (MLK) Jr. Boulevard in Chapel Hill, Orange County, North
Carolina (site).
The site is comprised of one land parcel that is approximately 10.24 acres in size and contains a
two-story approximately 35,000 sq ft building located in the north -central portion. The building
and associated parking areas are currently used for police department operations by the Town of
Chapel Hill (Town). South of the police department operations area, the topography slopes
downward along an embankment to a lower area where Bolin Creek and the Bolin Creek Trail
(hereinafter also referred to as the greenway) are located. Prior to purchase of the site by the
Town, the site was used by the previous owner as a borrow pit and fill site for coal combustion
products (CCPs) and construction debris. The primary compounds of concern (COCs)
associated with the site are metals associated with CCPs. A site location map is included as
Figure 1, and a site map is included as Figure 2.
The purpose of this recent risk assessment is to evaluate the potential risk to human health or
ecological receptors associated with the CCPs at the site, and whether additional remedial actions
or other measures are warranted to address these risks. As discussed in Section 2.0 below,
interim remedial measures were implemented by the Town in 2020 which included removal of
exposed CCPs along the Bolin Creek Trail. The risk assessment activities were completed in
general accordance with North Carolina Department of Environmental Quality (DEQ) and
United States Environmental Protection Agency (EPA) risk assessment guidance (DEQ, 2020,
DEQ, 2021a, EPA, 2018a, EPA, 2018b).
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This Risk Assessment Report is organized into sections to include the following:
• Site Background Information (Section 2.0)
• Environmental Setting (Section 3.0)
• Summary of Environmental Conditions (Section 4.0)
• Human Health Risk Assessment (Section 5.0)
• Ecological Risk Assessment (Section 6.0)
• Conclusions and Recommendations (Section 7.0)
• References (Section 8.0)
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2.0 Site Background Information
2.1 Site Location and Surrounding Land Use
The site is located at 828 MLK Jr. Blvd. in Chapel Hill, Orange County, North Carolina. The
location of the site is shown in Figure 1, and a general layout of the site including the building,
pavement, drainage features, vegetation, and greenway features is illustrated in Figure 2. The
approximate geographical coordinates of the site are: 35°55'36.69"N latitude and
79°03' 10.47"W longitude. The site parcel is zoned R-2 Residential 2 (4 units/acre) by the Town
of Chapel Hill.
Adjacent properties are zoned as R-2, with the exception of southern adjacent properties.
Southwest and southeast adjacent properties are zoned as R-4 Medium Density Residential
Conditional (10 units/acre) and the south adjacent properties are zoned as NC Neighborhood
Commercial.
The surrounding properties are occupied by the following:
• North and Northeast — Bolinwood Drive with residential properties located beyond
• East — Stratford Hills Apartments complex followed by vacant land
• South — Bolin Creek followed by Lloyd Tire & Alignment and Mobil -branded gas
station/Run-In-Jim's convenience store
• West — MLK Jr. Blvd. followed by vacant land with residential properties located
beyond
2.2 Site Description
The site is comprised of one land parcel that is approximately l 0.24 acres in size and contains a
two-story approximately 35,000 sq ft building located in the north -central portion of the site that
is currently used for police department operations. Asphalt parking lots are located in the
northwestern and central portions of the site, and wooded areas are located in the southern and
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eastern portions of the site. Bolin Creek traverses the southern portion of the site, and a portion
of the Bolin Creek Trail is located in the southern portion of the site just north of and parallel to
Bolin Creek. The site topography consists of an elevated area where the police building and
associated parking lots are located which slopes along an embankment to the south to a lower
area along Bolin Creek where the Bolin Creek Trail is located. Chain -link fencing prevents
access from the Bolin Creek Trail to the embankment along certain portions of the trail. Site
topography is indicated in Figure 1.
2.3 Site History
2.3.1 Site Ownership and Operational History
As indicated by Orange County Tax Records, the owner of the facility prior to the Town was
Richard W. Sparrow, who initially operated the site as a borrow pit from the late 1950s to the
early 1960s, and then as a fill site from the mid- 1960s to the mid- 1970s. The Town acquired the
property in 1980 and constructed the site building in the early 1980s. The building has been used
for police department operations by the Town since its construction. Additional municipal
offices have also been located within the site building.
The Town is currently evaluating potential on and off -site locations for mixed -used
redevelopment that may include the Municipal Services Center, residential housing, and retail.
As part of the evaluation process, the Town applied for entry into the DEQ Brownfields
Program, and received eligibility (Brownfields Project No. 23022-19-068) via a Letter of
Eligibility dated October 1, 2019.
2.3.2 Previous Environmental Investigations
Evidence of subsurface impacts associated with CCPs was first identified at the site during a
Phase I & Limited Phase II Environmental Site Assessment completed by Falcon Engineering,
Inc. in 2013. Investigation activities were then performed by Falcon and H&H under the
direction of the DEQ Inactive Hazardous Sites Branch (IHSB) between 2013 and 2016, and
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culminated in a Phase II Remedial Investigation (RI) Report dated August 14, 2017. The
investigation activities included collection and laboratory analysis of CCPs, groundwater, soil,
stream sediment, and surface water samples. In addition, an evaluation was performed to
identify where the CCPs were potentially exposed at the ground surface.
In 2019, the Town contracted Duncklee & Dunham (D&D) and Dr. Ken Rudo of Rudo
Toxicological Consultants (Rudo) to complete a preliminary human health and ecological risk
assessment for the site. The risk assessment focused on the area of Bolin Creek and the Bolin
Creek Trail, and included an evaluation of interim remedial measures (IRMs) to better control
the risk profile of the site. Prior to performing the risk assessment, D&D and Rudo identified
certain data gaps and requested that additional assessment be completed to support the risk
assessment activities. In response, H&H performed additional drainage pathway soil assessment,
fill material evaluation, and groundwater assessment, which is documented in a Results of Post -
Data Gap Assessment Report dated December 1, 2020.
The initial risk assessment results concluded that interim measures, including removal of
surficial coal ash in selected locations in the lower part of the site, would be protective of
greenway trail users. In 2020, IRMs were implemented. IRMs included excavation and off -site
disposal of soil and exposed CCPs along Bolin Creek Trail, stabilization and cover of exposed
CCPs along the embankment between the upper and lower portions of the site, and temporary
measures to address stormwater and erosion control in the area of the embankment. Specifically,
approximately 1,004 tons of soil/CCPs at the base of the embankment and along Bolin Creek
were excavated and transported off -site for disposal. In addition, super silt fencing and
hydroseed were placed along the embankment, and a new storm water diversion channel was
installed. The interim measures are documented in an Interim Remedial Measures Report dated
April 19, 2021.
Following completion of the 2020 IRMs, D&D (now part of SynTerra Corporation) completed a
Human Health and Ecological Risk Assessment Report dated May 6, 2021, which focused on
potential risks in the area of Bolin Creek and the greenway trail. With regard to human health
risk, the report concluded that the greenway trail is safe for users. With regard to ecological risk,
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the report concluded that ecological risk was likely minimal, but recommended additional
evaluation for certain constituents.
The Town requested that H&H perform additional risk assessment activities with the intent of
defining the final measures recommended to address CCP impacts, both under the current land
use scenario and possible future redevelopment scenarios. The results of the risk assessment
performed by H&H are documented in this report. The risk assessment performed by H&H
covered the site as a whole, including both the greenway trail area and the area of the current
municipal operations.
As referenced in Section 2.3.1, the site has been accepted into the NC Brownfields Program, and
mixed -used redevelopment that includes the Municipal Services Center, residential housing, and
retail is being contemplated for the site. The Brownfields Program implements standard
measures designed to address human -health risks for all projects, and did not request that the
Town prepare this Risk Assessment Report. However, the Town voluntarily elected to contract
H&H to complete the Risk Assessment in order to provide better explanation and transparency to
the public regarding how risks will be addressed for the site. Should the Town Council decide to
move forward with redevelopment of the site, future remediation, risk management, and/or
redevelopment activities would be performed under the oversight of the Brownfields Program.
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3.0 Environmental Setting
3.1 Site Topography
The site property is located in the Piedmont Physiographic Province of North Carolina. The
Piedmont province is a plateau that divides North Carolina's mountain and coastal plain regions.
It has variable topography, with elevations ranging from approximately 300 feet above mean sea
level (msl) in the eastern portion to approximately 1,500 feet msl in the western portion. The
Piedmont is separated from the Coastal Plain region by a fall line, or the point in which rivers
transition from rocky, shallow streams to smooth -flowing streams.
Overall, the site slopes to the south from an elevation of approximately 375 ft msl near
Bolinwood Drive to an elevation of approximately 300 ft above msl near Bolin Creek, which
transverses the southern boundary of the site. The site topography is segmented into two gently
graded areas referred to as the "upper level" and the "lower level" that are separated by a steep
embankment which generally runs east -west. The upper level includes the northern and central
portion of the site where the building and asphalt parking lots are located. The lower level of the
site gently slopes to the southeast toward Bolin Creek and includes the Bolin Creek Trail.
3.2 Surface Water Hydrology
The land surface across the site generally slopes to the south toward Bolin Creek. Stormwater
infrastructure in the upper level was upgraded in October through November 2020 to minimize
the potential for runoff from the upper level to the lower level. Super silt fencing was installed
along the flanks of the embankment and in other areas in the vicinity of the trail to minimize the
potential for stormwater to carry CCPs to the area of the trail and greenway. Portions of the
embankment were also hydroseeded with grass seed and a biodegradable growth medium to
provide erosion resistance to the slopes. In addition, stormwater upgrades were implemented in
the police parking lot and an existing stormwater outfall channel so that stormwater is diverted
from the embankment where CCPs are present at or below land surface which minimizes the
potential for future erosion of soil/CCPs along the embankment. Note that these are considered
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interim measures to address erosion along the embankment, and the Town is considering
permanent measures to be implemented in conjunction with site redevelopment activities.
Locations of site drainage features which discharge surface water to Bolin Creek are depicted in
Figure 2.
Bolin Creek and its tributaries are classified by DEQ as Class WS-V, Nutrient Sensitive Waters
(NSW) surface water bodies, and are part of the Cape Fear River basin. Class WS-V surface
waters are protected as upstream water supplies draining to waters used as drinking water
supplies. These waters are also protected for Class C uses, including secondary recreation,
fishing, wildlife, fish consumption, aquatic life including propagation, survival, and maintenance
of biological integrity, and agriculture. Secondary recreation includes wading, boating, and other
uses involving human body contact with water where such activities take place in an infrequent,
unorganized, or incidental manner. A NSW classification is a supplemental classification to
identify waters needing additional nutrient management due to excessive microscopic or
macroscopic vegetation growth.
Bolin Creek discharges into Little Creek, which feeds into Jordan Lake. Jordan Lake discharges
to the Haw River, which joins with the Deep River to form the Cape Fear River.
3.3 Geology
The site is located in the Piedmont Geologic Province of North Carolina, which consists of
metamorphic and igneous crystalline bedrock overlain by a region of fractured and folded
metamorphic and igneous crystalline bedrock. According to the Geologic Map of North Carolina
(1985), the bedrock in site area is described as metamorphosed granitic rock. More detailed
references (Cunningham and Daniel, 2001) describe the underlying bedrock as meta -igneous and
meta -volcanic felsic rocks. Meta -igneous felsic rocks are light colored, massive to foliated
metamorphosed igneous rock bodies, commonly with local shearing and jointing. Meta -volcanic
felsic rocks are primarily dense, fine-grained, light colored felsic tuffs and felsic crystal tuffs,
commonly with local shearing and phyllitic zones.
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Based on previous assessment activities, the native shallow soil generally consists of silty clay
saprolite which is approximately 5 to 15 ft thick. In areas where fill material is not present, the
saprolite is underlain by a partially weathered rock (PWR) zone that is approximately 5 ft thick,
and the PWR is underlain by bedrock. Depth to bedrock at the site generally ranges from
approximately 10 to 15 ft bgs in the northern portion of the site near Bolinwood Road and in the
southern portion of the site near Bolin Creek. Depth to bedrock in the central portion of the site
where fill material has been placed is approximately 45 ft to 50 ft bgs. In areas where fill has
been placed, the shallow cover soil generally consists of clayey silt fill which, in some locations,
appears to be mixed with CCP. See Section 4.2 for a discussion of the extent and thickness of
buried fill material across the site.
3.4 Hydrogeology
The occurrence and movement of groundwater in the Piedmont is within two separate yet
interconnected water -bearing zones. A shallow water -bearing zone occurs within the saprolite
(and may include alluvium near streams), and a deeper zone occurs within the underlying
bedrock. Groundwater in the shallow saprolite zone occurs in the interstitial pore spaces
between the grains comprising the unconsolidated saprolitic soils. Groundwater in this zone is
typically under water table or unconfined conditions. Groundwater movement is generally
lateral from recharge areas to small streams which serve as localized discharge points.
The occurrence and movement of groundwater in the underlying water -bearing zone within the
crystalline bedrock is controlled by secondary joints, fractures, and faults within the bedrock.
On a regional scale, the direction of groundwater flow is typically from highlands to major
streams and groundwater sinks. The saprolite has a higher porosity than the bedrock and serves
as a reservoir which supplies water to a network of fractures in the bedrock.
Based on the results of groundwater monitoring completed at the site, the direction of
groundwater flow in the uppermost unconfined aquifer is south-southeast across the site towards
Bolin Creek. The depth to groundwater is approximately 7 to 10 ft bgs in the most upgradient
portion of the site near Bolinwood Road, and 1 to 6 ft bgs in the most downgradient portion of
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the site near Bolin Creek. Groundwater is present at deeper depths in the central portion of the
site where the natural ground surface elevation has been modified due to fill placement.
Groundwater has been measured in the existing monitoring wells in the fill area at depths
ranging from approximately 30 to 40 ft bgs. However, prior assessment activities also identified
evidence of perched groundwater in the fill material, which is separated from the main
underlying unconfined aquifer. As such, the groundwater depths measured in some monitoring
wells (MW-IA, MW-1, MW-8, and MW-9) appear to reflect perched groundwater zones rather
than the main underlying aquifer. Uncontrolled fill areas such as the site, in which layers with
significantly different permeabilities are placed next to one another (i.e., debris with sand or a
gravel zone immediately overlying a silt or clay layer) have a high potential for perched
groundwater zones. Refer to the Results of Post -Data Gap Assessment Report prepared by H&H
and dated December 1, 2020 for additional discussion of lines of evidence for perched
groundwater conditions.
Historical tables and figures are included in Appendix A, including a summary of monitor well
construction and historical groundwater elevation data, a geologic cross-section, and an
unconfined aquifer potentiometric map.
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4.0 Summary of Environmental Conditions
The primary COCs associated with the site are metals associated with CCPs. Naturally -
occurring background levels of metals are also present at the site. An explanation of background
concentrations, extent of CCPs, and brief summaries of the site -specific COCs in soil,
groundwater, surface water, and sediment are presented in the sections below. Summaries of
historical data for site soil, groundwater, surface water, and sediment are included in Appendix
A.
4.1 Background Conditions
Metals, including the COCs for the site, are naturally occurring within North Carolina soils.
These compounds are derived from the natural elemental composition of the source rock and
compound concentrations are a reflection of the rock composition. Background samples
collected from the site contained concentrations of certain metals exceeding DEQ Preliminary
Soil Remediation Goals (PSRGs) in soil and stream sediment, which are attributed to naturally -
occurring metals in the parent bedrock. EPA and DEQ do not require remediation of
concentrations below naturally occurring background levels (EPA, 2002, DEQ, 2021).
Therefore, evaluation of site -specific background levels is important in determining
remedial goals. Note also that the DEQ PSRGs are initial screening levels based upon
conservative exposure assumptions. DEQ allows that final remedial goals be based upon a
risk evaluation using the DEQ risk calculator as discussed further in Section 5.0.
In order to determine whether metals detections at the site are related to fill materials or represent
background levels, H&H calculated site -specific Background Screening Values (BSVs). Based
on EPA guidance (EPA, 2015a, 2018a, 2018b), the BSVs for metals in soil consist of 95% upper
tolerance limits (UTLs) with 95% coverage determined using EPA's ProUCL calculator (EPA,
2015a). Due to a more limited data set which introduces more uncertainty in output of the
ProUCL calculator, the BSVs for stream sediment and surface water consist of the lower of the
maximum detected background concentration or twice the mean of background concentrations.
Appendix B contains details regarding the basis for the BSVs and documentation of the
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calculations. The BSVs are referenced in subsequent sections of this report when evaluating
whether concentrations detected in individual samples represent background conditions or
evidence of contamination.
4.2 Extent of CCPs
Based on prior assessment activities, fill materials placed at the site consist primarily of
construction and demolition debris and fill soil intermixed with zones of CCPs. The thickness of
the CCP zones primarily ranges from less than 1 ft to 3 ft, with some thicker zones up to 10 ft.
Fill materials were identified to depths of approximately 40 ft, although the deepest that CCPs
were observed was approximately 29 ft.
In the upper level of the site, CCPs are capped with clayey silt that ranges in thickness from less
than 1 ft to approximately 10 ft thick, with most areas having greater than 2 ft of soil cover. CCP
is exposed at the surface along the eastern and central portions of the embankment that separates
the upper and lower levels of the site. CCPs in the western portion of the embankment are
covered but with soil that is less than 2 ft thick. Erosion of CCPs along some portions of the
embankment historically resulted in deposition of a layer of CCPs in the lower level of the site
north and south of the Bolin Creek Trail. However, CCPs in the lower level were excavated as
part of the 2020 IRMs, and no significant CCPs are currently present in the lower level.
4.3 Soil and CCP Concentrations
Over 70 samples of soil and/or CCPs have been collected at the site over the course of historical
assessment activities. Concentrations of COCs for samples that were not removed during the
2020 IRMs were compared to the current DEQ residential health -based PSRGs,
industrial/commercial health -based PSRGs, and protection of groundwater PSRGs.
Concentrations of metals were also compared to site -specific BSVs prior to comparison to
PSRGs. The results of this comparison indicated concentrations of arsenic, barium, cobalt,
manganese, mercury, and selenium above current PSRGs and BSVs, with arsenic being the most
commonly detected constituent. Note that PSRGs are not intended as remediation goals and are
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based on conservative risk assumptions. DEQ guidance recommends comparison of
concentrations to PSRGs for initial screening purposes, but final remediation goals may be
determined based on risk evaluation performed using the NC Risk Calculator, as discussed
further in Section 5.0.
4.4 Groundwater
Multiple groundwater monitoring events have been performed at the site over the course of
historical assessment activities. Concentrations of COCs in groundwater samples were
compared to 15A NCAC 02L .0202 Groundwater Standards (2L Standards). As previously
mentioned, prior assessment data indicate that there are perched water zones in the fill material,
and groundwater samples collected from shallow wells in the fill are monitoring these perched
zones. Perched groundwater is likely present in some zones of CCPs or just below zones of
CCPs. Concentrations of metals above 2L Standards in groundwater samples from these wells
(MW-IA, MW-1, MW-8, and MW-9) are associated with the presence of CCPs within or near
perched groundwater. Some impacted perched groundwater may eventually migrate through
underlying unsaturated zones to groundwater in the main underlying unconfined aquifer;
however, this migration is slow and of low volume. As such, there is limited or no groundwater
impact in monitoring wells which are screened in non -fill zones in the unconfined aquifer,
including well MW-11D located directly below the fill and shallow downgradient monitoring
wells MW-3A and MW-4A which are located downgradient of the fill area.
4.5 Surface Water
Surface water samples have been collected from Bolin Creek during four sampling events
completed in 2013, 2014, 2016, and 2019 from three upstream locations, three locations adjacent
to the site, and three downstream locations. A surface water sample was also collected from a
drainage pathway at the site. No COCs were detected in surface water samples at concentrations
above 15A NCAC 2B Section .0100 Surface Water Quality Standards (2B Standards). Based
upon the surface water sample results, there is no evidence of surface water impact at the site
which would warrant further assessment or remediation.
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4.6 Stream Sediment
Stream sediment samples have been collected from Bolin Creek during two sampling events
completed in 2016 and 2019 from two upstream locations, two locations adjacent to the site, and
three downstream locations. Concentrations of COCs were compared to the current DEQ
residential health -based PSRGs, industrial/commercial health -based PSRGs, and protection of
groundwater PSRGs. Concentrations of metals were also compared to site -specific BSVs prior
to comparison to PSRGs. Manganese and/or hexavalent chromium were detected in two samples
at concentrations above PSRGs and site -specific BSVs. As previously mentioned, note that
PSRGs are not intended as remediation goals and are based on conservative risk assumptions.
DEQ guidance recommends comparison to PSRGs for initial screening purposes, but
remediation goals are determined based on risk evaluation performed using the NC Risk
Calculator, as discussed further in Section 5.0.
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5.0 Human -Health Risk Assessment
H&H evaluated potential human -health risks associated with COCs detected in soil,
groundwater, stream sediment, and surface water, and whether actions are warranted to address
these risks. Actions could include remediation activities, implementation of land -use restrictions
(LURs), or other measures to prevent exposures. Should the Town Council decide to move
forward with redevelopment of the site, LURs are expected to be included in a Brownfields
Agreement (BFA) with the DEQ Brownfields Program, which would be filed on the deed for the
property and remain in perpetuity.
Risk assessment calculations were performed using the DEQ Risk Calculator (June 2021), which
is an Excel -based calculator tool developed by DEQ that evaluates human -health risks using
equations and inputs that have been approved by DEQ and are consistent with EPA risk
assessment guidance. The methodology for the risk evaluation was in general accordance with
the risk assessment procedures detailed in DEQ and EPA risk assessment guidance (DEQ, 2020,
DEQ, 2021 a, EPA, 2018b).
5.1 Exposure Pathways Evaluation
An exposure pathway refers the mechanism by which people could potentially be exposed to
COCs. A complete exposure pathway means that there is potential for human exposure to
COCs, while an incomplete exposure pathway means that exposure is not possible due to
absence of COCs, absence of receptors, or inaccessibility (i.e., surface cover such as pavement,
no water supply well usage, etc). An exposure pathways evaluation was performed to identify
current and potential future complete pathways for receptor exposure to site COCs. Below is a
list of exposure pathways and a discussion of whether each pathway is complete for the site. For
convenience, these pathways are addressed using the same naming conventions and order used in
the DEQ Risk Calculator.
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Direct Contact Soil and Water Exposure Pathways
• Direct contact soil exposure pathway — This pathway covers health -based soil exposure
via ingestion, dermal contact, or outdoor inhalation of volatiles and particulates.
Receptor scenarios considered for this exposure pathway are detailed below.
o Resident — Site use is currently non-residential; therefore, the direct contact soil
exposure pathway is currently incomplete for the resident scenario. Under a future
scenario, this exposure pathway could become complete in certain areas if the site is
used for residential purposes.
o Non-residential worker — The direct contact soil exposure pathway is currently
complete for non-residential workers in the area of the police department building
where impacted soil is not covered by pavement, building floor slabs, or non -
impacted soil cover. Under a future land use scenario, this exposure pathway could
become complete in additional areas if building floor slabs, pavement, or non -
impacted soil cover are removed.
o Construction worker — Per DEQ guidance (DEQ, 2021 a), the Risk Calculator uses
very conservative default inputs that represent worst -case situations and may result in
overly restrictive risk values when evaluating the construction worker pathway.
Therefore, the results of the construction worker evaluation performed using the Risk
Calculator should not drive a cleanup level. Instead, the results are intended to be
used to help guide safety concerns for imminent or potential future construction
activities. An Environmental Management Plan (EMP) detailing methods to prevent
construction worker exposure and manage impacted soil during construction activities
is required by the Brownfields Program and will be specified in a LUR.
Implementation of this EMP will result in the direct contact soil exposure pathway
being incomplete for a construction worker. This pathway was evaluated as part of
the risk assessment to help identify potential areas of concern to be addressed by the
EMP, but does not drive proposed remediation goals.
o Recreator — The southern portion of the site is used as a public green space and
contains the Bolin Creek Trail for recreational use; therefore, this pathway is
currently complete for greenway users under both the current and future land use
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scenarios. For consistency, the recreator receptor is referred to as a greenway user
throughout this report.
• Direct contact groundwater use exposure pathway — This pathway covers health -based
groundwater exposure via ingestion, dermal contact, or inhalation associated with use of
groundwater from a water supply well. For the subject site, assessment data do not
indicate groundwater impacts extending beyond the site property boundary, no water
supply wells are currently present at the site, and a LUR preventing the future installation
of water supply wells is proposed as part of the BFA. Implementation of this LUR will
result in the groundwater use exposure pathway being incomplete. Therefore, this
pathway was not evaluated as part of the risk assessment. However, possible direct
contact with surface water and sediment from groundwater seepage to surface water is
considered an exposure pathway as discussed below.
• Direct contact surface water exposure pathway — This pathway covers health -based
surface water exposure via ingestion or dermal contact during a recreational scenario.
This pathway is considered complete for greenway users in the area of Bolin Creek under
both the current and future land use scenarios.
• Direct contact sediment exposure pathway — This pathway covers health -based stream
sediment exposure via ingestion, dermal contact, or outdoor inhalation of volatiles and
particulates. This pathway is not specifically covered in the DEQ Risk Calculator. Per
DEQ guidance (DEQ, 2021 a), this pathway was evaluated by entering sediment
concentrations under the direct contact soil exposure pathway for a greenway user in the
area of Bolin Creek. However, note that this approach overestimates risk since sediment
will usually be covered by water, which limits human exposure and eliminates inhalation
risk.
Vapor Intrusion Exposure Pathway
• Vapor intrusion exposure pathway — The vapor intrusion pathway covers indoor
inhalation risk due to intrusion of volatile organic compound vapors from subsurface soil
and/or groundwater into buildings. COCs for the site are non-volatile metals associated
with CCPs; therefore, this pathway is not considered complete.
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Contaminant Migration Pathway
• The contaminant migration pathways evaluate leaching of compounds from soil to
groundwater, and migration of impacted groundwater towards either a downgradient
water supply well or a downgradient surface water body. The Risk Calculator contains
tools for predictive modeling of these pathways; however, per DEQ guidance (DEQ,
2021 a), groundwater monitoring data that confirm the plume is stable and unlikely to
impact a downgradient receptor are more reliable to support risk management decisions.
As discussed in Section 4.3, groundwater monitoring data for the site indicate limited or
no groundwater impact in monitoring wells which are screened in non -fill zones in the
unconfined aquifer. Groundwater impacts, if any, will not migrate beyond the site
property boundary due to the hydraulic barrier formed by Bolin Creek. In addition, as
discussed in Section 4.4, surface water monitoring data indicate no significant impacts to
Bolin Creek. Based on monitoring data, contaminant migration pathways are not
considered a concern for the site.
5.2 Exposure Unit Designations
For the purpose of risk characterization, the site was divided into exposure units (EUs) that
represent areas of similar land use and potential receptors. Three EUs were defined for the site,
and the EUs are depicted in Figure 3. A description of each EU and associated exposure
pathways is provided below.
• EU #1 encompasses the upper level in the vicinity of the existing police department
building and associated parking areas. EU #1 is currently non-residential. Future
redevelopment may include residential use. Therefore, calculations were performed to
evaluate the soil direct contact pathway for a resident, non-residential worker, and
construction worker within EU #1. The direct contact groundwater use pathway will be
managed via a LUR preventing the installation of water supply wells. No surface water
or stream sediment are located within EU #1.
• EU #2 encompasses the area of Bolin Creek and the adjacent trail area, which is also
referred to as the lower level of the site. EU #2 is currently used for recreational
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purposes only. EU #2 is located within a flood zone; therefore, commercial or residential
redevelopment is not viable. Calculations were performed to evaluate the soil, surface
water, and stream sediment direct contact pathways for a greenway user, and the soil
direct contact pathway for a construction worker within EU #2. The direct contact
groundwater use pathway will be managed via a LUR preventing the installation of water
supply wells.
• EU #3 encompasses the embankment between EU #1 and EU #2. The embankment is
not currently in use and partially fenced off to prevent access from the adjacent EU #2
greenway area. Although occupancy and uses of EU #3 are inherently limited due to the
steep slope, calculations were conservatively performed to evaluate the soil direct contact
pathway for a resident, non-residential worker, construction worker, or greenway user
within EU #3. The direct contact groundwater use pathway will be managed via a LUR
preventing the installation of water supply wells. No surface water or stream sediment
are located within EU #1.
• Note that the potential for erosion to transport impacts from the area of the embankment
(EU #3) into the greenway area (EU #2) is an additional concern. The Town
implemented temporary measures to minimize the potential for erosion as part of the
IRMs implemented in 2020; however, H&H recommends implementation of permanent
measures to prevent erosion in conjunction with site redevelopment activities.
5.3 Exposure Point Concentrations
Exposure point concentrations were defined for the soil, sediment, and surface water direct
contact exposure pathways. Analytes considered in the risk assessment conservatively included
all detected constituents designated by DEQ as COCs requiring analysis for the site (see DEQ
letter dated February 11, 2016). The data sets used for the risk assessment included the
following:
• The soil EPC data set included the full set of historical soil sampling data, with several
exceptions. First, soil samples that were excavated during the 2020 IRMs were removed
from the data set. Secondly, at locations that were sampled more than once, only the
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more recent samples were included in the data set. Lastly, based on EPA risk assessment
guidance (EPA, 2018b), soil samples collected at depths 2 ft bgs or less were used for
risk calculations for residents, non-residential workers, and greenway users, and samples
collected at depths of 10 ft bgs or less were used for risk calculations for construction
workers. Note that if impacted soil or CCPs at deeper depths are exposed during site
redevelopment, additional risk evaluation should be performed to confirm surface soils
do not exceed acceptable risk levels. If the site is redeveloped, the Brownfields Program
will also likely require confirmatory sampling and risk evaluation in areas of potentially
impacted soil or CCPs that are not covered by impervious surfaces (buildings, pavement,
etc.) or at least 2 ft of clean fill.
• For surface water, more recent data is considered most representative of current
conditions, but EPCs also need to account for possible variations in surface water
concentrations over time. To account for potential variability over time, the surface
water EPC data set included surface water samples collected within the past five years
(2016 and 2019 sampling events).
• For stream sediment, two sampling events have been performed to date in 2016 and 2019.
The locations sampled in 2016 were resampled in 2019, so the 2019 is considered most
representative of current conditions and was used as the EPC data set.
Per DEQ guidance (DEQ, 2020), maximum concentrations for each constituent of concern
detected in the referenced data sets were used as the EPCs. Following initial risk calculations,
the EPC dataset was further refined to exclude metals detected at concentrations below site -
specific BSVs. As previously discussed, the BSVs established for the site consisted of the 95%
UTL with 95% coverage for background soil, and the lower of two times the mean or the
maximum detected concentration for background surface water and sediment. EPC tables are
included in Appendix C.
5.4 Exposure Parameters
The default exposure parameters incorporated in the DEQ Risk Calculator were used for the risk
evaluation for a resident, non-residential worker, and construction worker. These exposure
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parameters are consistent with EPA default exposure parameters (EPA, 2021), where established,
and are intended to represent a reasonable maximum exposure (RME) scenario. RME is defined
by EPA as the highest exposure that is reasonably expected to occur at a site, generally assumed
to be in the range of the 90th and 90 percentiles (EPA, 2001). To calculate risks specific for
greenway users, H&H calculated site -specific exposure factors based on greenway user polling
data collected by the Town. Specifically, for adult and child exposure frequency, soil exposure
time, and water exposure time, H&H used values equal to or more conservative than the 98th
percentile of responses reported during the greenway user survey. This approach is consistent
with RME as defined by EPA, and represents "worst -case" exposures. Following is a brief
summary of the most pertinent exposure parameters, but please refer to the NC Risk Calculator
documentation in Appendix C for a full list of exposure parameters used in the calculations:
• Residential exposure for 6 years (yrs) as a child and 20 yrs as an adult (26 yrs total), 350
days per year (d/yr), and 24 hours per day (hr/d).
• Non-residential exposure for 25 yrs (adult only), 250 d/yr, and 8 hr/d.
• Construction worker exposure for 1 yr (adult only), 250 d/yr, and 8 hr/day.
• Greenway user exposure for 6 yrs as a child and 20 yrs as an adult (26 yrs total), 364 d/yr
and 1 hr/d as an adult, and 52 d/yr and 0.5 hr/d as a child.
• Dermal contact with soil parameters assumes exposure of head, hands, forearms, lower
legs, and feet for a resident and greenway user, and exposure of head, hands, and
forearms for a non-residential worker and construction worker.
• Soil ingestion parameters assume ingestion of 200 milligrams per day (mg/d) of soil by a
child (greenway user or resident), and 100 mg/d of soil by an adult (greenway user,
resident, or non-residential worker). Increased ingestion of 330 mg/d of soil is assumed
for a construction worker.
• Significantly increased outdoor inhalation of particulates is assumed for a construction
worker, with assumed particulates at levels greater than the National Ambient Air Quality
Standard established under 40 Code of Federal Regulations Part 50 for particle pollution.
5.5 Toxicity Factors
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The conservative default toxicity factors incorporated in the DEQ Risk Calculator were used for
the risk evaluation. Note that these toxicity factors account for possible development effects for
pregnant women.
5.6 Risk Assessment Results
For the direct contact pathways, the DEQ Risk Calculator calculates values for potential cancer
risk (CR) and potential non -cancer hazard quotient (HQ) or hazard index (HI) as described
below:
• CR is defined as the incremental probability of an individual developing cancer over a
lifetime as a result of exposure to a potential carcinogen. For example, a CR of one in
10,000 (1.0E-04) indicates one person in 10,000 may have an increased risk of cancer
due to exposure to a chemical.
• HQ is defined as the ratio of the amount of a contaminant a person is exposed to versus
the amount that may cause non -cancer harmful effects, while HI is defined the sum of
HQs for individual contaminants for a given scenario. For example, a HI of less than 1
indicates the exposure is unlikely to cause non -cancer harmful effects.
For each receptor scenario, CR and HQ values for complete exposure pathways are summed to
determine the cumulative risk for each receptor. The cumulative CR and HI values for each
receptor are then compared to the DEQ acceptable risk values. DEQ considers a cumulative CR
of 1.0E-4 and HI of 1.0 or less to be acceptable (DEQ, 2021 a). Similarly, EPA considers
exceedances of a CR of IE-04 and HI of I to be triggers requiring remediation or other actions to
reduce exposures (EPA, 2018b).
Note that calculated cumulative CR and HI values do not include risks associated with lead.
Currently, there is no EPA reference dose or cancer potency factor to quantify risks associated
with exposures to lead. Exposure risks to lead are characterized based on predicted blood lead
levels. The DEQ Risk Calculator flags a lead concentration when the concentration exceeds the
DEQ health -based residential or industrial/commercial PSRGs for lead (400 mg/kg and
800 mg/kg, respectively). Lead has not been detected at concentrations above DEQ health -based
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PSRGs in samples collected at the site; therefore, lead is not considered to be a compound posing
a significant risk for the site.
Cumulative CR and HI values calculated for each exposure unit and receptor scenario are
summarized in Table 1. Risk calculator documentation is included in Appendix C. A discussion
of the results is presented below.
5.6.1 Exposure Unit #1— Upper Level
EU #1 covers the upper level in the area of the existing police department building. In the area
of EU #1, calculated CR and HI values do not exceed DEQ acceptable risk limits for a non-
residential worker. Therefore, the area of EU #1 is considered safe for non-residential workers,
and no further evaluation of this exposure unit/receptor is considered warranted.
For a future resident in EU #1, the calculated cumulative CR value is acceptable; however, the
calculated HI value exceeds the DEQ acceptable risk level of 1, both with and without
background concentrations included. As previously referenced, background concentrations are
excluded when determining remedial goals for the site. With background levels excluded, the
COC driving the risk level above 1 is limited to manganese within the S-4 sample. This sample
was collected at a depth of 1 ft bgs in the wooded area southwest of the police department
building during the initial site assessment activities in April 2013, as reported in the Phase I &
Limited Phase II Environmental Site Assessment prepared by Falcon Engineering and dated July
18, 2013. If the site is redeveloped for residential use, H&H recommends remediation (ex.,
excavation, cover to prevent exposure) or other actions (ex., resampling to verify concentrations)
to address impacts in the area of sample S-4. Samples driving exceedances of residential risk
levels are identified on Figure 4A.
For a construction worker, the calculated cumulative CR value was acceptable; however,
calculated HI value exceeds the DEQ acceptable risk level of 1, both with and without
background concentrations included. The COCs driving the risk level greater than 1 include
manganese, arsenic, and mercury. Samples driving exceedances of construction worker risk
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levels are identified on Figure 4B. As previously discussed, the Risk Calculator uses very
conservative default inputs that represent worst -case situations and may result in overly
restrictive risk values when evaluating the construction worker pathway. Construction worker
risks will be managed via a LUR requiring preparation of an EMP, which will detail measures to
prevent construction worker exposure, manage impacted soil during construction activities, and
minimize the potential for off -site migration of impacted soil via surface water or windborne
pathways.
5.6.2 Exposure Unit #2 — Lower Level
EU #2 covers the lower level in the area of the greenway trail and Bolin Creek. For a current
and future greenway user, the calculated CR and HI values do not exceed DEQ acceptable risk
limits. Therefore, the area of EU #2 is considered safe for greenway users, and no further
evaluation of this exposure unit/receptor is considered warranted.
For a construction worker, the initial evaluation including background levels indicated the
calculated cumulative CR value was acceptable, but the calculated HI value exceeds the DEQ
acceptable risk level of 1. If background levels are excluded, the calculated CR and HI values do
not exceed DEQ acceptable risk levels. Because risks associated with contamination do not
exceed acceptable risk levels, no remediation or other measures are considered warranted to
address construction worker risks in EU#2. However, the Brownfields Program will likely
require an EMP for the site as a whole, including EU #2, which will detail measures to prevent
construction worker exposure, manage impacted soil during construction activities, and minimize
off -site migration pathways.
5.6.3 Exposure Unit #3 - Embankment
EU #3 covers the area of the embankment between the upper and lower level. As previously
noted, EU #3 is not currently used and occupancy is limited by fencing and a steep slope;
however, H&H conservatively evaluated the same receptors designated for the upper and lower
levels for this exposure unit.
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For a potential current or future greenway user, the calculated CR and HI values do not exceed
DEQ acceptable risk limits. Therefore, the area of EU #3 is considered safe for greenway users,
and no further evaluation of this exposure unit/receptor is considered warranted.
For a potential current or future non-residential worker, the calculated CR and HI values do not
exceed DEQ acceptable risk limits. Therefore, the area of EU#3 is considered safe for non-
residential workers, and no further evaluation of this exposure unit/receptor is considered
warranted.
For a potential future resident, the calculated cumulative CR value was acceptable; however,
calculated HI value exceeds the DEQ acceptable risk limit, both with and without background
levels included. With background levels excluded, the COC driving the exceedance is arsenic in
samples S-7, HH-10, and HH-11. CCPs are exposed in areas of the embankment and the
samples driving the risk exceedance were CCP samples. H&H recommends remediation or other
measures (several examples given above) to address exposed CCPs in the area of the
embankment. Samples driving exceedances of residential risk levels are identified on Figure 4A.
For a construction worker, the calculated cumulative CR value was acceptable; however, the
calculated HI value exceeds the DEQ acceptable risk level, both with and without background
levels included. The COCs driving the exceedance include manganese and arsenic. Samples
driving exceedances of construction worker risk levels are identified on Figure 4B. Construction
worker risks will be managed via a LUR requiring preparation of an EMP, which will detail
measures to prevent construction worker exposure, manage impacted soil during construction
activities, and minimize potential off -site migration.
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6.0 Ecological Risk Assessment
Due to the presence of potential ecological receptors in the area of Bolin Creek, H&H conducted
initial screening activities related to ecological risk assessment. Based on DEQ guidance (DEQ,
2021b), the initial screening activities consisted of comparison of detected concentrations to the
Ecological Screening Values (ESVs) established by EPA Region 4. The Guidelines for
Performing Screening Level Ecological Risk Assessments within the Division of Waste
Management (DENR, 2003) and EPA Region 4 Ecological Risk Assessment Supplemental
Guidance (EPA, 2018a) were consulted during the initial screening; however, please note that
H&H's evaluation did not constitute a full Screening Level Ecological Risk Assessment
(SLERA).
Per DEQ and EPA guidance (DENR, 2003, EPA, 2018a), EPA ESVs are based on conservative
endpoints and ecological effects data, and represent preliminary screening criteria to evaluate the
potential for ecological risk (or lack thereof). ESVs are not intended to represent remediation
goals. The purpose of the initial ESV screening activities performed by H&H was to evaluate
whether additional actions are warranted to further evaluate or address ecological risks for the
site. This section details the EPCs used for the screening, and the results of the ESV screening
for surface water, sediment, and soil.
6.1 Exposure Units
The ecological risk assessment included evaluation of data with respect to the same exposure
units established in the human health risk assessment. The EUs were further evaluated with
respect to the potential for significant ecological receptors to be present, as detailed below.
• EU #1 encompasses the upper level in the vicinity of the existing police department
building. Ecological receptors are less likely to be present in the area of EU #1 due to the
buildings and pavement associated with the police department building. However, some
ecological receptors could potentially be present in the wooded areas surrounding the
facility; therefore, this unit was conservatively screened for ecological risk. No stream
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sediment or surface water are located within this unit, so the only complete exposure
pathway for ecological receptors is surface soil exposure.
• EU #2 encompasses the area of Bolin Creek and the adjacent trail area. EU #2 is
considered the unit with the highest likelihood of potential ecological receptors.
Complete exposure pathways for ecological receptors include surface soil exposure,
sediment exposure, and surface water exposure.
• EU #3 encompasses the embankment between EU # 1 and EU #2. The potential for
ecological receptors in this area is considered moderate. No stream sediment or surface
water are located within this unit, so the only complete exposure pathway for ecological
receptors is surface soil exposure.
• As previously discussed, note that the potential for erosion to transport impacts from the
area of the embankment (EU #3) into the greenway area (EU #2) is an additional concern.
The Town implemented temporary measures to minimize the potential for erosion as part
of the interim remediation measures implemented in 2020; however, H&H recommends
implementation of permanent measures to prevent erosion in conjunction with site
redevelopment activities.
6.2 Exposure Point Concentrations
Analytes considered in the risk assessment conservatively included all detected constituents
designated by DEQ as COCs requiring analysis for the site (see DEQ letter dated February 11,
2016). Similar to the human -health risk assessment, the data set used for the risk assessment
included the following:
• The surface water EPC data set included surface water samples collected within the past
five years (2016 and 2019 sampling events).
• The stream sediment EPC data set included the most recent samples collected in 2019.
• The soil EPC data set included the full set of historical soil sampling data with the
exception of (1) soil samples that were excavated during the 2020 IRMs, (2) locations
that were resampled, in which case only the latest data was included, and (3) samples
collected at depths of more than 2 ft bgs. Samples collected from 0 to 2 ft bgs were used
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based on prior guidance from DEQ personnel. This is consistent with or more
conservative than EPA guidance, which recommends collection of samples for terrestrial
ecological risk assessment at depths on the order of 25 to 30 cm, or 0.8 to 1 ft (EPA,
2015b).
Maximum concentrations for each constituent of concern detected in the referenced data sets
were used as the EPCs. Concentrations were initially compared to ESVs directly without
consideration of background concentrations. Where concentrations exceeded ESVs,
concentrations were also compared to the established site -specific BSVs to evaluate exceedances
potentially attributable to contamination rather than background conditions. As previously
discussed, the BSVs established for the site consisted of the 95% UTL with 95% coverage for
background soil, and the lower of two times the mean or the maximum detected concentration
for background surface water and sediment.
6.3 Ecological Screening Evaluation
The results of the ecological risk evaluation for the soil, stream sediment, and surface water
exposure pathways are detailed below. COCs identified at concentrations above BSVs and ESVs
are shown on Figure 5.
6.3.1 Soil Ecological Screening
The designated soil EPCs within the three exposure units were compared to the EPA Soil ESVs
as summarized in Table 2. The results of the comparison for each exposure unit are discussed
below.
Exposure Unit #1
Within EU #1 (upper level), soil concentrations were identified above the EPA ESVs in multiple
samples. However, the majority of the detections are below the site -specific BSVs and therefore
considered representative of background conditions. Concentrations above both EPA ESVs and
BSVs were identified only in soil samples S-4 and MW-7.
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Sample S-4 contained cadmium, cobalt, copper, manganese, and nickel at concentrations above
ESVs and BSVs. As previously discussed, this sample was collected at a depth of 1 ft bgs in the
wooded area southwest of the police department building during the initial site assessment
activities in April 2013. This sample was also identified as a driver for residential risk
exceedances during the human health risk assessment.
Sample MW-7 is a soil sample collected from the boring for well MW-7 at a depth of 0-1 ft bgs
in 2016. This sample contained copper at a concentration above both the ESV and BSV. This
sample was collected in the eastern portion of the site approximately 120 ft cross -gradient of the
area of CCPs. The detected concentration is higher than copper concentrations collected from
CCPs in the source area. Based on review of the data, the copper detected in sample MW-7 is
likely not associated with the CCP disposal area and is considered an outlier. Additional
sampling may be beneficial to confirm concentrations in the area of well MW-7.
It should be noted that DEQ does not commonly require evaluation of ecological risks for soil
(DEQ, 2021b). As such, DEQ may not require additional actions with regard to the exceedances
of ESVs in S-4 and MW-7. If required by DEQ or if the Town wishes to take voluntary actions,
H&H recommends remediation or other measure to address or further evaluate potential
ecological risks in the area of samples S-4 and MW-7.
Exposure Unit #2
Within EU #2 (lower level), soil concentrations were identified above the EPA ESVs in multiple
samples. However, the majority of the detections are below the site -specific BSVs and therefore
considered representative of background conditions. Concentrations above both EPA ESVs and
BSVs were identified only in sample SED-13 which is a drainage pathway sample located near
the bridge of the Bolin Creek Trail.
At the SED-13 location, samples were collected at both 0-2 and 2-6 inches bgs. Barium was
detected at concentrations above the ESV and BSV in both sample depths. Selenium and
strontium were also detected at concentrations above the ESVs and BSVs in the 0-2-inch bgs
sample depth.
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As previously referenced, DEQ does not commonly require evaluation of ecological risks for soil
(DEQ, 2021b). As such, DEQ may not require additional actions with regard to the exceedances
of ESVs in SED-13. If required by DEQ or if the Town wishes to take voluntary actions, H&H
recommends remediation or other measure to address or further evaluate potential ecological
risks in the area of sample SED-13.
Exposure Unit #3
Within EU #3 (embankment), concentrations were identified above both EPA ESVs and BSVs in
each sample collected (S-7, H-9, H-10, and H-11). Constituents detected above ESVs and BSVs
include arsenic, barium, beryllium, mercury, selenium, and strontium. CCPs are exposed in
areas of the embankment and the samples indicating exceedances were CCP samples. H&H
recommends remediation or other measures to address exposed CCPs in the area of the
embankment.
6.3.2 Stream Sediment Ecological Screening
The designated stream sediment EPCs in the area of Bolin Creek (EU #2) were compared to the
EPA Sediment ESVs, as summarized in Table 3. The results of the comparison indicated barium
in samples SED-4 (Adjacent to the site) and SED-5 (Downstream near the southeast property
boundary) and total chromium in samples SED-4 (Adjacent) and SED-7 (Downstream and off -
site) at concentrations above the EPA ESVs. For these exceedances, concentrations were then
compared to the established BSVs. The concentrations were found to be below the BSVs, and
are therefore considered representative of background conditions. The fact that these
constituents represent background conditions is further confirmed by the detection of both
barium and chromium at concentrations above EPA ESVs in the upgradient background
sediment samples collected at the site.
Note that Table 3 also lists EPA Region 4 Refinement Screening Values (RSVs) for sediment.
The RSVs are based on less conservative ecological effects data, and are intended to be used as a
second -tier screening where ESVs are exceeded. Although sediment concentrations appear
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indicative of background conditions and therefore do not warrant remediation, the concentrations
(including those at background locations).do not exceed RSVs and therefore are not considered a
significant ecological risk.
6.3.3 Surface Water Ecological Screening
The designated surface water EPCs in the area of Bolin Creek (EU #2) were compared to the
EPA Region 4 Acute and Chronic Surface Water ESVs, as well as the NC 2B Standards. The
ESVs and 2B Standards for some constituents vary based on hardness. Based on historical
sampling, the average hardness in Bolin Creek was calculated as 54.5 milligrams per liter
(mg/L). Based on this value, the published ESVs based on a hardness of 50 mg/L were used.
NC 2B Standards were derived using the DEQ Hardness -Dependent Metal Calculator dated
July 26, 2021, and the average site -specific hardness of 54.5 mg/L. For constituents with no
established 2B Standard, concentrations were compared to the NC In -Stream Target Values for
Surface Water (July 26, 2021).
Table 4 provides a summary of surface water EPCs in comparison the referenced ecological
screening criteria. As shown, no concentrations were found to exceed EPA Region 4 Acute and
Chronic Surface Water ESVs, NC 2B Standards, or NC In -Stream Target Values for Surface
Water.
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7.0 Conclusions and Recommendations
H&H has completed human -health and ecological risk assessment activities for the property
located at 828 MLK Jr. Boulevard in Chapel Hill. The purpose of the risk assessment activities
was to evaluate potential human health and ecological risks for CCPs at the site under the current
land use scenario and possible future redevelopment scenarios. The risk assessment was
performed in general accordance with DEQ and EPA risk assessment guidance (DEQ, 2020,
DEQ, 2021a, EPA, 2018a, EPA 2018b), using conservative inputs intended to represent
reasonable maximum exposure scenarios. A summary of the results is presented below.
Human -Health Risk Assessment Results
The human -health risk assessment results indicated the following:
• Human -health risk was evaluated for possible future residents in the area of EU #1 (upper
level) and EU #3 (embankment). The results of the risk evaluation indicated that
acceptable risk levels were exceeded for a future resident in both units (with and without
background concentrations included) with risks being driven by metals in the following
locations:
o In the area of EU #1 (upper level), the driver for unacceptable risk levels for a
resident is the manganese concentration in soil sample S-4.
o In the area of EU #3 (embankment), the drivers for unacceptable risk levels for a
resident are arsenic concentrations in samples S-7, HH-10, and HH-11.
• Human -health risk was evaluated for possible current or future non-residential workers in
the area of EU #1 (upper level) and EU #3 (embankment). The results of the risk
evaluation indicated acceptable risk levels for a non-residential worker in both units.
Therefore, the site is considered safe for non-residential workers under both current and
future use scenarios.
• Human -health risk was evaluated for possible future construction workers in the area of
all three exposure units (upper level, lower level, and embankment). The results of the
risk evaluation indicated acceptable risk levels were exceeded for a construction worker
in all three units. If background concentrations are removed, acceptable risk levels were
exceeded for a construction worker in EU #1 (upper level) and EU #3 (embankment).
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• Human -health risk was evaluated for possible current and future greenway users in the
area of EU #2 (lower level) and EU #3 (embankment). The results of the risk evaluation
indicated acceptable risk levels for greenway users in both units. Therefore, the site is
considered safe for greenway users.
Ecological Risk Assessment Results
The results of the ecological risk screening indicated the following:
• The area of Bolin Creek (EU #2) is the area with the highest likelihood of potential
ecological receptors. The results of the risk evaluation indicated no significant ecological
risk for surface water and sediment in Bolin Creek.
• Exceedances of ESVs for multiple metals were identified in samples of exposed CCP
collected along the embankment in EU #3 (S-7, HH-9, HH-10, and HH-11).
• Localized exceedances of ESVs were also identified at two soil sample locations within
EU #1 (S-4 and MW-7) and one individual soil sample location within EU #2 (SED-13).
Recommendations
H&H's recommendations to address potential human -health and ecological risks identified as
part of this risk assessment are detailed below. In addition to recommendations related to
specific sample locations which are drivers for potential risks, in some cases LURs are
recommended to confirm the assumptions made during the risk assessment activities remain
valid. LURs are expected to be covered under a future BFA, which would be prepared under the
jurisdiction of the DEQ Brownfields Program and filed on the deed for the property. The
Brownfields Program requires annual certifications from the property owner that LURs are being
complied with in perpetuity, which will confirm that potential risks addressed via LURs will be
managed long-term.
• Exposed CCPs are present in the area of the embankment. The risk evaluation indicated
exceedances of acceptable risk levels for a resident, construction worker, and/or
ecological receptors based on metals concentrations in several samples of exposed CCPs
collected in the embankment area (S-7, HH-9, HH-10, and HH-11). The potential for
erosion to transport CCPs from the area of the embankment into the greenway area is
considered an additional concern. The Town implemented temporary measures to
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minimize the potential for erosion as part of the interim remediation measures
implemented in 2020; however, H&H recommends implementation of permanent
measures to address exposed CCPs and prevent erosion in the embankment area. These
measures could effectively be performed in conjunction with site redevelopment
activities.
• If the site is redeveloped for residential use, H&H recommends remediation or other
actions (ex., excavation, impervious cover to prevent exposure, resampling to verify
concentrations) to address impacts in the upper level in the area of sample S-4.
• Outside of the embankment area, the ecological risk screening indicated localized
exceedances of ESVs at two soil sample locations within EU #1 (S-4 and MW-7) and one
individual soil sample location within EU #2 (SED-13). DEQ does not commonly
require evaluation of ecological risks for soil (DEQ, 2021b). As such, DEQ may not
require additional actions with regard to the exceedances of ESVs in these samples. If
required by DEQ or if the Town wishes to take voluntary actions, H&H recommends
remediation or other measures to address or further evaluate potential ecological risks in
the area of samples S-4, MW-7, and SED-13.
• To address construction worker risks, H&H recommends implementation of an
anticipated LUR requiring preparation of an EMP, which will detail measures to prevent
construction worker exposure, manage impacted soil and minimize the potential for off -
site migration during construction (i.e., redevelopment) activities.
• The risk assessment calculations were based on soil samples collected at depths of 0 to
2 ft bgs for a resident, non-residential worker, and greenway user, and samples collected
at depths of 0 to 10 ft bgs for a construction worker. If impacted soil or CCPs at deeper
depths are exposed during site redevelopment, additional risk evaluation should be
performed to confirm that potential exposure to these soils does not exceed acceptable
risk levels. If the site is redeveloped, the Brownfields Program will also likely require
confirmatory sampling and risk evaluation in areas of potentially impacted soil or CCPs
that are not covered by impervious surfaces (buildings, pavement, etc.) or at least 2 ft of
clean fill.
• H&H recommends a LUR preventing the future installation of water supply wells or
other use or exposure of groundwater at the site.
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8.0 References
Cunningham and Daniel, 2001. Investigation of Ground -Water Availability and Quality in
Orange County, North Carolina. Cunningham, W.L. and C.C. Daniel, III, US
Geological Survey. Raleigh, NC. Water -Resources Investigations Report 00-4286.
DENR, 2003. Guidelines for Performing Screening Level Ecological Risk Assessments within
the North Carolina Division of Waste Management. North Carolina Department of
Environment and Natural Resources (currently DEQ), Division of Waste Management.
October 2003.
DEQ, 2016. Chapel Hill Police Department Property Letter. North Carolina Department of
Environmental Quality. February 2016.
DEQ, 2020. Technical Guidance for Risk -Based Environmental Remediation of Sites (Revised),
North Carolina Department of Environmental Quality. April 2020.
DEQ, 2021 a. Guidelines for Assessment and Cleanup of Contaminated Sites, North Carolina
Department of Environmental Quality — Division of Waste Management Superf ind
Section Inactive Hazardous Sites Branch. July 2021.
Dragun and Chekiri, 2005. Elements in North American Soils, Second Edition. Dragun, James,
and Khaled Chekiri. 2005.
Falcon, 2013. Phase I & Limited Phase II Environmental Site Assessment. Falcon Engineering,
Inc. October 2013.
H&H, 2017. Phase II Remedial Investigation (RI) Report. Hart & Hickman, PC. August 2017.
H&H, 2020. Results of Post -Data Gap Assessment. Hart & Hickman, PC. December 2020.
H&H, 2021. Interim Remedial Measures Report. Hart & Hickman, PC. April 2021.
NCGS, 1985. Geologic Map of North Carolina: North Carolina Geological Survey, General
Geologic Map. North Carolina Geological Survey. 1985.
Synterra, 2021. Human Health and Ecological Risk Assessment Report. Synterra Corporation.
May 2021.
USEPA, 2001. Risk Assessment Guidance for Superfund: Volume III Part A. U.S.
Environmental Protection Agency, Office of Emergency and Remedial Response.
December 2001.
35
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USEPA, 2002. Role of Background in the CERCLA Cleanup Program. U.S. Environmental
Protection Agency, Office of Solid Waste and Emergency Response, Office of
Emergency and Remedial Response. April 2002.
USEPA, 2015a. ProUCL Version 5.1 User Guide. U.S. Environmental Protection Agency,
Office of Research and Development. October 2015.
USEPA, 2015b. Determination of the Biologically Relevant Sampling Depth for Terrestrial and
Aquatic Ecological Risk Assessments. U.S. Environmental Protection Agency,
Ecological Risk Assessment Support Center, National Center for Environmental
Assessment, Office of Research and Development. October 2015.
USEPA, 2018a. Region 4 Ecological Risk Assessment Supplemental Guidance (Update). U.S.
Environmental Protection Agency, Scientific Support Section, Superfund Division, EPA
Region 4. March 2018.
USEPA, 2018b. Region 4 Human Health Risk Assessment Supplemental Guidance. U.S.
Environmental Protection Agency, Scientific Support Section, Superfund Division, EPA
Region 4. March 2018.
USEPA, 2021. Regional Screening Levels (RSLs) — User's Guide. U.S. Environmental
Protection Agency. May 2021.
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Table 1 (Page 1 of 1)
Summary of Human Health Risk Assessment Results
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
RISK ASSESSMENT RESULTS INCLUDING BACKGROUND CONCENTRATIONS
Exposure Pathway
Residential
Non -Residential Worker
Construction Worker
Greenway User
Carcinogenic Risk
Hazard Index
Carcinogenic Risk
Hazard Index
Carcinogenic Risk
Hazard Index
Carcinogenic Risk
Hazard Index
Exposure Unit #1 - Upper Level
Soil Direct Contact
2.4E-05
3.6E+00
4.8E-06
2.4E-01
7.0E-06
1.1 E+01
N/A
N/A
Exposure Unit #2 - Lower Level
Soil Direct Contact
N/A
N/A
N/A
N/A
1.4E-06
3.6E+00
8.4E-06
4.1 E-01
Sediment Direct Contact
N/A
N/A
N/A
N/A
N/A
N/A
1.8E-06
9.1 E-02
Surface Water Direct Contact
N/A
N/A
N/A
N/A
N/A
N/A
3.2E-07
1.7E-02
Cumulative Risk for Exposure
Unit #2*
N/A
N/A
N/A
N/A
1.4E-06
3.6E+00
8.7E-06
4.2E-01
Exposure Unit #3 - Embankment
Soil Direct Contact
9.4E-05
3.1 E+00
2.0E-05
2.2E-01
4.4E-06
8.8E+00
3.4E-05
4.6E-01
RISK ASSESSMENT RESULTS EXCLUDING BACKGROUND CONCENTRATIONS
Exposure Pathway
Residential
Non -Residential
Construction Worker
Greenway User*
Carcinogenic Risk
Hazard Index
Carcinogenic Risk
Hazard Index
I Carcinogenic Risk
Hazard Index
Carcinogenic Risk
Hazard Index
Exposure Unit #1 - Upper Level
Soil Direct Contact
2.1E-05
1.3E+00
4.7E-06
9.1E-02
5.4E-06
1.1E+01
N/A
N/A
Exposure Unit #2 - Lower Level
Soil Direct Contact
N/A
N/A
N/A
N/A
8.1 E-07
3.9E-01
8.0E-06
7.5E-02
Sediment Direct Contact
N/A
N/A
N/A
N/A
N/A
N/A
7.1 E-13
2.1 E-03
Surface Water Direct Contact
N/A
N/A
N/A
N/A
N/A
N/A
3.2E-07
1.7E-02
Cumulative Risk for Exposure
Unit #2
N/A
N/A
N/A
N/A
8.1 E-07
3.9E-01
8.3E-06
9.1 E-02
Exposure Unit #3 - Embankment
Soil Direct Contact
8.9E-05
2.1 E+00
2.0E-05
1.5E-01
3.4E-06
8.5E+00
3.3E-05
3.1 E-01
Notes:
N/A = Not applicable
Bold Red indicates an exceedance of NCDEQ acceptable risk levels (Carcinogenic Risk <1.0E-04 and Hazard Index <1.0).
* Cumulative risk calculated for EU #2 since more than one exposure pathway is complete. Cumulative risk indicates the higher of the sediment or soil risk, combined with the surface water risk. This is
considered appropriate since a receptor could not be exposed to both soil and sediment at the same time and the same exposure pathways are covered by both risk calculations.
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Table 2 (Page 1 of 1)
Soil Ecological Screening Table
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
Sample ID
Sample Date
Material Sampled
(Soil or CCP)
Sample
Depth
(ft or in
b9s)
U
ai
m
E
�
20
E
7
�
E
7
E
o
U
E
>
m o
x
r U
E
7
o
r
C
E
.2
o
L
m
m
°
a
n
o�
�
N
c
@
U)
E
L
0
E
c
E
7
m
r(n
E
7
C
o
w
E
t
E
7
m
c
>
N
Site -Specific BSV(1)
3.015
87.86
0.929
0.313
5.725
70.2
70.2
36.31
77.3
59.11
1,149
0.256
19.49
2.503
43.19
0.981'
227
230
EPA Region 4 Soil ESVI2I
18
330
2.5
0.36
0.34
26
23
13
28
11
220
0.013
38
0.52
96
0.05
7.8
46
Upper
Level Samples (Exposure Unit #1)
S-4
04/29/13
CCP
1 ft
14
24
ND
1.5
NA
NA
22
30
65
20
1,500
0.011
43
NA
ND
21
120
HH-1
11/03/16
Soil
0-1 ft
5.9
120
1.00
<0.29
0.45
20.55
21
7.9
25
27
350
0.052
8.8
0.69
31
<0.58
48
50
11/03/16(5)
Soil
0-1 ft
3.4
110
0.79
<0.35
0.54
19.46
20
8.4
17
18
360 BH
0.067
12
<0.
30
<0.71
41
35
HH-2
11/03/16
Soil
0-1 ft
4.9
140
0.93
<0.29
0.43
13.57
14
12
21
30
260
0.085
5.9
1.0
25
<0.58
48
43
HH-3
11/03/16
Soil
0-1 ft
9.9
200
1.30
<0.33
0.46 J
17.54
18
7.8
31
24
350
0.076
8.9
2.4
36
<0.65
53
100
HH-4
11/03/16
Soil
0-1 ft
2.4
72
1.00
<0.28
0.50
44.5
45
16
37
2.3
630
<0.023
33
<0.56
42
0.60
73
70
HH-5
11/03/16
Soil
0-1 ft
2.4
73
0.75
<0.30
<0.14
23
23
8.4
19
9.3
410
<0.025
14
1.2
23
<0.60
39
51
HH-6
10/27/16
Soil
0-1 ft
NA
NA
NA
NA
<0.33
20
20
NA
NA
NA
NA
NA
NA
NA
NA
NA
HH-7
10/27/16
Soil
0-1 ft
NA
NA
NA
NA
<0.61
22
22
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
MW-7
11/01/16
Soil
0-1 ft
2.6
67
0.87
<0.30
0.89
9.11
10
3.9
180
7.6
100
0.030
2.9
<0.59
6.7
<0.59
61
46
Embankment Samples (Exposure Unit #3)
S-7
01/31/14
CCP
0-4 ft
44
2,500
NA
ND
1.4
27.6
29
NA
NA
11
NA
0.44
4.5
NA
NA
NA
HH-9
04/03/19
CCP
0-1 ft
3.37
131
0.398 J
0.178 J
<1.29
12.7
12.7
5.97
14.5
NA
260
0.31
3.59
0.722
33.2
NA
NA
NA
HH-10
04/03/19
CCP
0-1 ft
60.3
2,970
5.14
0.162 J
<1.60
13.8
13.8
9.84
51.3
NA
73.3
0.22
17.1
5.04
269
NA
NA
NA
HH-11
04/03/19
CCP
0-1 ft
42.5
3,260
5.9
0.220 J
1 0.467 J
18.7
19.2
13.4
55.3
NA
113
1 0.43
23.5
9.05
1 234
NA
NA
NA
Lower Level Samples (Exposure Unit #2)
SS-7
02/18/16
Soil
2-12 in
3.1
84
0.60
ND
NA
NA
14
6.9
15
13
500
0.038
5.9
31
ND
37
37
HH-8
10/27/16
Soil
0-1 ft
3.6
100
1.00
<0.30
<0.35
19
19
12
29
18
570
0.036
9.0
28
<0.60
52
54
MW-6
11/02/16
Soil
0-1 ft
2.9
38
0.61
<0.26
0.21 J
9.79
10
9.5
23
12
570
0.082
8.2
1.0
22
0.81
31
77
SED-3A
04/05/19
Soil
0-1 ft
3.45
33.9
0.418 J
<0.582
<1.16
17.4
17.4
16.5
6.97
NA
560
<0.0054
5.82
0.237 J
9.6
NA
NA
NA
SED-5A
04/04/19
Soil
0-1 ft
1.25
13.5
0.156 J
<0.571
0.352 J
13.2
13.6
5.95
39.1
NA
243
0.0071
4.38
<0.571
10.9
NA
NA
NA
SED-8
04/05/19
Drainage Pathway Soil
2-6 in
2.41
49.1
0.313 J
0.122 J
<1.25
12.0
12
7.01
14.3
NA
423
0.063
4.66
1.01
15.2
NA
NA
NA
SED-9
04/05/19
Drainage Pathway Soil
2-6 in
1.16
33.8
0.199 J
<0.660
0.461 J
21.6
22.1
9.11
10.1
NA
431
0.013
6.68
<0.660
16.7
NA
NA
NA
SED-10
04/05/19
Drainage Pathway Soil
2-6 in
1.29
24.4
0.118 J
0.221 J
0.418 J
12.0
12.4
4.43
10.8
NA
195
0.037
4.03
0.273 J
8.1
NA
NA
NA
SED-12
08/27/19
Drainage Pathway Soil
0-2 in
4.73
102
0.765 J
0.214 J
<1.68
27.6
27.6
6.17
23.1
NA
341
0.042
7.69
0.961
25.4
NA
NA
NA
04/05/19
Drainage Pathway Soil
2-6 in
3.97
122
0.499 J
0.204 J
<1.74
9.45
9.45 B
6.04
19.7
NA
319
0.077
4.95
1.36
32.8
NA
NA
NA
SED-13
08/27/19
Drainage Pathway Soil
0-2 in
12.4
958
1.56
0.284 J
<2.03
29.4
29.4
13.9
38.9
NA
538
0.12
19.2
3.07
125
NA
NA
NA
04/05/19
Drainage Pathway Soil
2-6 in
14.5
724
1.1
0.171 J
<1.58
14.0
14
7.58
27.1
NA
563
0.075
8.73
1.69
70.5
NA
NA
NA
SED-18
04/05/19
Drainage Pathway Soil
2-6 in
4.53
137
0.534 J
<0.689
<1.38
18.7
18.7
11.1
28.2
NA
464
0.051
9.00
1.85
32.6
NA
NA
NA
SED-19
04/05/19
Drainage Pathway Soil
2-6 in
1.55
20.0
0.161 J
<0.588
0.435 J
21.7
22.1
7.98
8.38
NA
266
0.0073
4.94
0.334 J
15
NA
NA
NA
SED-20
04/05/19
Drainage Pathway Soil
2-6 in
0.792
31.4
0.152 J
<0.687
5.76
5.76 B
4.5
9.1
NA
360
0.012
2.19
0.263 J
11.5
NA
NA
NA
SED-21
04/05/19
Drainage Pathway Soil
2-6 in
1.12
25.9
0.149 J
<0.591
20.9
20.9
4.44
6.58
NA
221
0.011
2.70
0.286 J
12.8
NA
NA
NA
Excavation H-3
05/11/20
Soil
1-2 ft
2.41
71.0
<3.28
<1.31
0.410 J
40.2
40.6
14.1
43.4
NA
251
0.0485 J
12.5
1.46 J
58.1
NA
NA
NA
Excavation H-5
05/11/20
Soil
1-2 ft
1.10 J
1 74.5
<3.04
<1.22
0.497 J
21.1
21.6
8.25
16.9
NA
558
<0.0486
6.77
<3.04
32.2
NA
NA
NA
Excavation H-6
05/11/20
Soil
1-2 ft
1.02 J
96.0
<2.97
<1.19
<1.19
14.9
14.9
7.57
10.7
NA
557
0.0222 J
4.03
<2.97
1 20.5
NA
NA
NA
Excavation H-7
11/09/20
Soil
0-1 ft
1.10 J
73.7
0.767 J
<1.22
<1.22
8.04
8.04
3.68
15.0
NA
233
0.022
4.63
0.479 J
9.6
NA
NA
NA
Excavation 1-1
04/08/20
Soil
1-2 ft
2.91
67.2
<2.77
<1.11
0.457 J
26.2
26.7
13.0
18.3
NA
594
0.042
8.25
<2.77
26.3
NA
NA
NA
Excavation 1-2
04/08/20
1 Soil
1 1-2 ft
3.65
74.1
<2.85
<1.14
0.313 J
23.3
23.6
12.0
21.4
NA
544
0.022
8.70
<2.85
17.2
NA
NA
NA
Excavation 1-3
04/08/20
Soil
1-2 ft
2.18
61.5
<2.88
<1.15
0.387 J
13.1
13.5
1 9.23
1 19.5
NA
419
0.019
1 6.02
<2.88
13.3
NA
NA
NA
Notes:
Concentrations reported in milligrams per kilogram (mg/kg).
1) Site -Specific Background Screening Value (BSV) represents 95% upper threshold level (UTL) with 95% coverage calculated using EPA ProUCL 5.1.
*Insufficient data to calculate 95% UTL; therefore, site -specific BSV indicates 2x mean concentration with non -detectable concentrations calculated as half the reporting limit
2) EPA Region 4 Soil Ecological Screening Value (ESV) (March 2018).
Bold denotes concentration above or equal to EPA Soil ESV.
Bold/Shaded denotes concentration above or equal to EPA Soil ESV and site -specific BSV.
NA = Not Analyzed
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
Table shows constituents detected in soil samples collected between 0 and 2 ft bgs, excluding background samples, samples that have been excavated, and samples collected from locations resampled at a later date.
Refer to Appendix A for a summary of additional sampling data.
https://harthick.sh,repoint.com/,ites'Mast,rFiles-I/Shared Documents/AAA-Master Projects/Town of Chapel Hill (TCH)/TCH-009 -Police Station -Remedial Services/Risk Assessment/Tables/T2 - T4 Eco Risk Assess Tables Hart & Hickman, PC

Table 3 (Page 1 of 1)
Stream Sediment Ecological Screening Table
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
E
E
E
o
Sediment Sampling Point
�"
°
2
ID
Sample Date
p
a)
(n
o
U
.�
E
7
_
M
C
_t=
U
Q
0)
U
Y
,E
7
.0
X
>
N
O
O
Q
U
N
N
U
.E
0
fU
-0
-0
E
E
�
in
Site -Specific BSV(')
2.74
38.4
0.48
0.79
69.5
70
16.388
13.8
759
0.0078
9.92
0.409
16.9
EPA Region 4 Sediment ESV(2)
9.8
20
NS
NS
NS
43.4
50
31.6
460
0.17*
22.7
0.72*
NS
EPA Region 4 Sediment RSV(')
33
60
NS
NS
NS
111
NS
149
1,100
0.17*
48.6
1.2*
NS
SED-3 (Adjacent)
04/05/19
1.36
16.4
0.111 J
0.670 J
13.5
14.2
5.18
20.2
225
0.0054 J
4.81
9.2
SED-4 (Adjacent)
04/05/19
2.35
20.3
0.191 J
0.456 J
63.8
64.3
7.26
8.39
293
0.0080
10.5
0.344 J
30.7
SED-5 (Downstream)
04/04/19
1.82
24.3
0.233 J
0.595 J
16.8
17.4
5.9
8.86
399
4.86
6.2
SED-6 (Downstream)
04/04/19
1.96
17.3
0.247 J
0.517 J
24.9
25.4
6.57
9.25
308
0.0058
7.15
8.4
SED-7 (Downstream)
1 04/04/19
1 1.35
1 16.4
1 0.179 J
0.995 J
59.4
60.4
6.47
6.77
1 262
1 0.0025 J
9.04
8.1
Notes
Concentrations reported in milligrams per kilogram (mg/kg).
1) Site -Specific Background Screening Value (BSV) indicates two times the mean detected background concentration or maximum detected background concentration, whichever is smaller
2) EPA Region 4 Sediment Ecological Screening Value (ESV) for freshwater (March 2018)
3) EPA Region 4 Sediment Refinement Screening Value (RSV) for freshwater (March 2018)
*Indicates the lower of the aquatic versus wildlife based ESVs and RSVs.
Bold denotes concentration above EPA Sediment ESV.
Bold/Shaded denotes concentration above EPA Sediment ESV and site -specific BSV.
Red denotes concentration above EPA Sediment RSV.
Red/Shaded denotes concentration above EPA Sediment RSV and site -specific BSV.
NS = Not Specified
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
Table shows constituents detected in the most recent set of surface water samples, excluding background samples. Refer to Appendix A for a summary of additional sampling data.
https://harthick.sharepoint.com/sites/MasterFiles-1/Shared Documents/AAA-Master Projects/To of Chapel Hill (TCH)/TCH-009 -Police Station -Remedial Services/Risk Assessment/Tables/T2- T4 Eco Risk Assess Tables Hart & Hickman, i1.

Table 4 (page 1 of 1)
Surface Water Ecological Screening Table
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
a
v;
E
Surface Water Sampling Point
ID
Sample Date
p
o
a�
C:
F
E
E
ECO
f6
Q
C
C
(5
O
0 O
O Q
COU
.�
ti
d
fCIO-0
E
to
Site -Specific BSV(')
0.44
27
0.53
0.16
1.2
22.2
0.33
0.11
100
NC 2B Standard(2)
10(t)
1,000(t)
11
1.6(7)
5.33
NS
25(t)
5(t)
14,000(7)
EPA Region 4 Surface Water ESV (Acute)(3)
340
2,000
16
120
7.3
1,680
261
20
48,000
EPA Region 4 Surface Water ESV (Chronic)(3)
150
220
11
19
5.16
1 93
29
5
1 5,300
11 /03/16
27
34
100
SW-3 (Adjacent)
11/03/16(8)
27
33
110
04/05/19
0.45
25.7
0.62
0.26
2.8
37.4
0.50
0.11 J
88.8
11 /03/16
27
25
110
SW-4 (Adjacent)
04/05/19
0.42
23.6
0.14
1.0
1 24.6
0.26 J
0.10 J
1 89.1
04/05/19(8)
0.41
23.7
0.14
0.98
24.8
0.26 J
0.088 J
87.7
11/03/16
26
24
100
SW-5 (Downstream)
04/04/19
0.40
16.9
0.14
0.88
19.5
0.21 J
0.12 J
81.8
SW-6 (Downstream)
04/04/19
0.40
16.9
0.14
0.84
18.7
0.21 J
0.11 J
81.3
SW-7 (Downstream)
04/04/19
0.42
18.4
0.16
1.1
23.1
0.23 J
0.10 J
86.7
04/05/19
0.40
32.1
0.73
0.36
3.2
29.5
0.62
0.11 J
69.9
SW-21 (Drainage Pathway)
04/05/19(9)
0.15
18.3
0.094 J
3.1
9.3
0.43 J
43.5
Notes:
Concentrations reported in micrograms per liter (pg/L).
1) Site -Specific Background Screening Value (BSV) indicates two times the mean detected background concentration or maximum
detected background concentration, whichever is smaller.
2) North Carolina Surface Water Quality Standard (NC 2B Standard) adopted per 15A NCAC 2B Section .0100. Unless otherwise noted,
values are the lowest of the Freshwater, Water Supply, and Human Health values because Bolin Creek is a WS V classification surface
water.
3) EPA Region 4 Surface Water Ecological Screening Value (ESV) for freshwater (March 2018).
4) 2B Standards derived using site -specific hardness data for surface water samples SW-1 through SW-7 and the DEQ Hardness -
Dependent Metal Calculator dated July 26, 2021. Mean hardness for these samples was 54.5 mg/L. Value shown is the lower of the acute
versus chronic values.
5) EPA ESVs based on estimated hardness of 50 mg/L, which is the value reported by EPA closest to the measured site -specific hardness
6) 2B Standard shown for total chromium indicates the lower of the hexavalent and trivalent chromium values.
7) No 2B Standard established, value shown is the NC In -Stream Target Values for Surface Water (July 26, 2021). Value shown is the
lower of the acute versus chronic values.
8) Duplicate sample taken.
9) Sample was field filtered.
Bold denotes concentration above NC 2B Standard.
Bold/Shaded denotes concentration above NC 2B Standard and site -specific BSV
Red denotes concentration above EPA Surface Water ESV (lower of acute or chronic).
Red/Shaded denotes concentration above EPA Surface Water RSV and site -specific BSV.
NS = Not Specified
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
(t) = Based upon measurement of total recoverable metal. See 15A NCAC 02B .0211 for more information.
Table shows constituents detected in surface water samples within the past five years, excluding background samples. Refer to Appendix
A for a summary of additional sampling data.
Hart & Hickman, PC
https://harthick.sharepoint.com/sites/MasterFiles-1/Shared Documents/AAA-Master Projects/Town of Chapel Hill (TCH)/TCH-009 - Police Station - Remedial Services/Risk Assessment/Tables/T2 - T4 Eco Risk Assess Tables

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QUADRANGLE
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LEGEND
SITE PROPERTY BOUNDARY
RESIDENTIAL BOLIN CREEK
F, TOPOGRAPHIC CONTOUR ELEVATION (FT MSL)
CCP UNDER > 2 FT COVER
. . . . . . . . . .
CCP UNDER < 2 FT COVER
CCP EXPOSED AT GROUND SURFACE (HYDROSEEDED)
STORMWATER CULVERT
BOLIN CREEK TRAIL
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BUILDING 358
348
STORM OUTFALL CHANNEL
RESIDENTIAL CCP AREA DESIGNATION
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0 115 230
SCALE IN FEET
TITLE
SITE MAP
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TOWN OF CHAPEL HILL
28 MARTIN LUTHER KING JR. BOULEVARD
`-\' ,: CHAPEL HILL, NORTH CAROLINA
2923 South Tryon Street -Suite 100
hart 'Na- h i c k m a n Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f
SMARTER ENVIRONMENTAL SOLUTIONS License # C-1269 / #C-245 Geology
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-
-
-
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RESIDENT
BOLIN CREEK
z
.
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r
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MONITORING WELL LOCATION (FALCON ENGINEERING)
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f
m
1
TEMPORARY MONITORING WELL LOCATION (FALCON
A
PARKING
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LOT
SOIL BORING LOCATION FALCON ENGINEERING
x
GP12
� SURFACE WATER SAMPLE LOCATION (FALCON
O7
O
:ORA.
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c
m
MONITORING WELL LOCATION (H&H)
G
x
GP11
SOIL SAMPLE LOCATION (H&H)
K
t
POLICE
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A DRAINAGE PATHWAY, SURFACE WATER/SEDIMENT
BUILDING
SAMPLE LOCATION (H&H)
S-7 (1/31/14)
-
STORMWATER CULVERT
DEPTH FT BGS 0-4'
RESIDENT ( )
GP1 MW_1
S1
_ � _
GP10
GP4
RESIDENT
BOLIN CREEK TRAIL
ARSENIC
44
MW-1A
HH-1
+ L HH-2
1'
GP9
EXPOSURE UNIT #1 - UPPER LEVEL
GP8
a EXPOSURE UNIT #2 -LOWER LEVEL
STORMWATER
`
GP2
GP5
POND
�'
EXPOSURE UNIT #3 - EMBANKMENT
PARKING
S-4 (4/29/13)
MW-11
LOT
DEPTH (FT BGS) 1'
GP3
HH-3
SAMPLE ID &DATE
MANGANESE 1,500
MW-9
GP7
S7
GP6
r
HH-10 (4/3/19) SAMPLE DEPTH
S4
HIJ S5 MW-8
DEPTH (FT BGS) 0-1'
ARSENIC 60.3
CONCENTRATION
HH-9
(mg/kg)
RISK DRIVERS
BG
..r
BG-8
G_1
S6
®
MW-6
HH-10
MW-7
SED-12\ HH-11
SED-8
MW 2
SED-�3.•
HH-11 (4/3/19)
NOTES:
' SW-2/ `
BRIDGE
SS-1 H 1
H_4
�•
DEPTH( T BGS)
0-1'
1. ONLY COMPOUNDS THAT DRIVE EXCEEDANCES OF
SW-1/ SED-2_ B
I-1`
ARSENIC
42.5 -
ACCEPTABLE RISK LEVELS (CARCINOGENIC RISK > 1.0E-04
SED-1
SED-9
SED-11 H 3. H-2
AND HAZARD INDEX> 1.0)ARE SHOWN.
BG-1
I-2 SED-16 HH-7 H 5 •
aa`
BG-4 BG-3 BG-2
H-6'
SED-3A SS-7 HH-6 1-3 MW-3A SED-17 -3 MW-4A
CHAIN -LINK
APARTMENTS
VC`F 2. FT BGS FEET BELOW GROUND SURFACE
SED-10
SS-6 SS-4 SS-2SS-3A SS-3
FENCE
SW-3/
SS-5
SED-3
SED-14 SED-15 H-7
HH-10 (4/3/19)
SED-18
DEPTH (FT BGS)
0-1-
GAS
ARSENIC
60.3
-� STATION
—SW-4/
SED-4 HH-8
Y
'
`
BC-2
T+
APPROXIMATE
0 115 230
AUTO
SED-19 SED-20
REPAIR
SCALE IN FEET
R GH BEET
SW-21
RESIDENTIAL HUMAN HEALTH RISK
�
-
SED-21
DRIVERS MAP
SED-5A
SW-5/
:.Z ��.JFCT
TOWN OF CHAPEL HILL
SED-5
828 MARTIN LUTHER KING JR. BOULEVARD
CHAPEL HILL, NORTH CAROLINA
'A
SED-6
� South Tryon Street -Suite 0
f
hart h i c k m a n
Charlotte, North Carolina 282032923
704-586-0007(p) 704-586-0373(f
License # C-1269 / #C-245 Geology
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DATE: 9-10-21 REVISION NO. 0
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JOB NO. TCH-009 FIGURE NO. 4A

W ti / 2
A.
LEGEND
.'�
D
SITE PROPERTY BOUNDARY
GP-12 (2/3/14)
RESIDENT
BOLIN CREEK
z
DEPTH (FT BGS) 2-4-
ARSENIC 52
MONITORING WELL LOCATION (FALCON ENGINEERING)
�
2
?R
TEMPORARY MONITORING WELL LOCATION (FALCON
PARKING
ENGINEERING)
LOT
T)
SOIL BORING LOCATION (FALCON ENGINEERING)
�GP12
_
SURFACE SAMPLE LOCATION (FALCON
OER
~�
ENGINEERING)
c
GP-5 (4/3/19)
m
MONITORING WELL LOCATION (H&H)
DEPTH (FT BGS) 4-6'
D
GP11
z
SOIL SAMPLE LOCATION (H&H)
ARSENIC 95.9
KD F
r r
POLICE
jDEPARTMENT
- DRAINAGE PATHWAY, SURFACE WATER/SEDIMENT
L BUILDING
SAMPLE LOCATION (H&H)
STORMWATER CULVERT
S-7 (1/31/14)
RESIDEN
GP1 MW-1
S1
GP10
RESIDENT
BOLIN CREEK TRAIL
DEPTH (FT BGS)
0-4'
W-1A iHH-1
GP4 HH-2
111CCC
1 ARSENIC
44
-
GP9
EXPOSURE UNIT #1 - UPPER LEVEL
GP8
EXPOSURE UNIT #2 -LOWER LEVEL
STORMWATER
`
GP2
GP5
POND
...
� EXPOSURE UNIT #3 - EMBANKMENT
S-4 (4/29/13)
PARKING- —
DEPTH (FT BGS)
1'
MW-
LOT
H H-3
MANGANESE 1,500
GP3
SAMPLE ID & DATE
MW 9
GP7
S7
GP6
HH-10 (4/3/19) SAMPLE DEPTH
y�
S4
HH-4 S5 MW-8
DEPTH (FT BGS) 0-1'
GP-6 (2/4/14)
ARSENIC 60.3
CONCENTRATION
BG _6
HH-9
DEPTH (FT BGS)
9-11,
-
(mg/kg)
BG-7
1
HH-5
ARSENIC
65
1 RISK DRIVERS
BG-8
G-1
S6
MERCURY
11
.
_ 1
MW-6 ' �
HH-10
MW-7
t
- _
SED-12\
HH-11
USED-8
MW 2
`
HH-11 (4/3/19)
NOTES:
SW-2/�,
BRIDGE
SED-�3.• SS-1 H 1
�
DEPTH (FT BGS)
0-1'
is
* r ■ '� '*
1. ONLY COMPOUNDS THAT DRIVE EXCEEDANCES OF
SW-1/ SED-2' B -
1_1`
H_4
ARSENIC
42.5
ACCEPTABLE RISK LEVELS (CARCINOGENIC RISK > 1.0E-04
SED-1
SED-9
SED-11 H_3.
H-2
AND HAZARD INDEX> 1.0)ARE SHOWN.
BG-1
�.
1-2 SED-16 HH-7 H-5
BG-4 BG-3 BG 2
1-3
SED-3A SS-7 HH-6 MW-3A
SED -17 SS-3 W-4A
CHAIN -LINK
APARTMENTS
2. FT BGS = FEET BELOW GROUND SURFACE
SED-10
SS-6 35-4
SS-2SS-3A
FENCE
SW-3/
SS-5
SED-3
SED-14
SED-15 H-7
HH-10 (4/3/19)
SED-18
DEPTH (FT BGS)
0-1'
GAS
ARSENIC
60.3
-� STATION
SED-4
HH-8
Y
`
BC-2
T+
APPROXIMATE
0 115 230
'
AUTO
SED-19 SED-20
REPAIR
H-4 (5/11/20)
SCALE IN FEET
R GH REET
SW-21
DEPTH (FT BGS)
2-3'
TITLE CONSTRUCTION WORKER HUMAN HEALTH
SED-21
MANGANESE
1,480
RISK DRIVERS MAP
SED-5A
SW-5/
Paaecr
TOWN OF CHAPEL HILL
SED-5
828 MARTIN LUTHER KING JR. BOULEVARD
CHAPEL HILL, NORTH CAROLINA
SED-6
2923 South Tryon Street -Suite 0
f
h a rt h i c k m a n
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f
License # C-1269 / #C-245 Geology
_ •*
I� �` ,•�t
SMARTER ENVIRONMENTAL SOLUTIONS
■r 41
S W-7/
DATE: 9-10-21 REVISION NO. 0
4s+
SED-7
JOB NO. TCH-009 FIGURE NO. 4B

Appendix A
Historical Data Tables and Figures

Table A-1 (page 1 of 2)
Summary of Post-IRM Soil Analytical Data
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
Sample ID
Sample Date
Material Sampled
(Soil or CCP)
Sample
Depth
(k or in
bgs)
c
E
-
_
_
12
E
3
E
-
E
E
0
_
E
o
_
-
2
.o
-
3
E
-
E
E
3
E
E
E
2
E
-
E
_A
E
_1.
E
E
o
E
E
Site-S ecific
BS
NA
ND
3.015
87.86
0.929
NA
0.313
NA
5.725
70.2
70.2
36.31
77.3
NA
59.11
NA
1,149
0.256
NA
19.49
NA
2.503
NA
NA
43.19
0.981'
227
230
PSRG -Protection of GroundwateP
110,000
0.90
5.8
580
63
45
3.0
INS
3.8
360,000
INS
0.90
700
150
270
NS
65
1.0
7.1
130
INS
2.1
3.4
INS
1,500
0.28
350
1,200
PSRG- Residential Health-basedl"
16,000
6.3
0.68
3,100
31
3,100
14
INS
0.31
23,000
INS
4:7
630
1 11,000
1 400
NS
380
2.3
78
310
1 INS
78
1 78
INS
1 9,400
1 0.16
1 78
4,700
PSRG - Industrial/Commercial Health-based'I
1 230,000
93
1 3.0
1 47,000
1 470
1 47,000
200
1 INS
6.5
1 350,000
INS
70
1 9,300
1 160,000
1 800
1 INS
1 5,600
1 9.7
1 1,200
1 4,700
1 INS
1,200
1 1,200
1 INS
1 140,000
1 2.3
1 1,200
70,000
Upper
Level Samples
S-4
04/29/13
CCP
1 ft
23,000
ND
14
24
ND
NA
1.5
9,900
NA
22
30
65
59,000
20
9,000
1,500
0.011
NA
43
680
ND
NC
150
NA
21
120
S-5
01/31/14
CCP
0-4ft
NA
NA
37
2,800
NA
NA
ND
NA
1.3
19.7
21
NA
NA
NA
10
NA
NA
0.30
NA
NA
NA
3.2
ND
NA
NA
NA
NA
NA
S-6
01/31/14
CCP
0-4ft
NA
NA
43
3,200
NA
NA
ND
NA
2.7
1943
22
NA
NA
NA
12
NA
NA
0.42
NA
NA
NA
6.1
ND
NA
NA
NA
NA
NA
GP-1
02/03/14
CCP
8-12 ft
NA
NA
3.5
86
NA
NA
ND
NA
ND
8.8
8.8
NA
NA
NA
26
NA
NA
0.083
NA
NA
NA
ND
ND
NA
NA
NA
NA
NA
GP-2
02/03/14
CCP
26-28it
NA
NA
41
1,100
NA
NA
ND
NA
ND
19
19
NA
NA
NA
11
NA
NA
0.24
NA
NA
NA
4.0
ND
NA
NA
NA
NA
NA
GP-3
02/03/14
CCP
10-12 it
NA
NA
48
1,200
NA
NA
ND
NA
0.53
22.47
23
NA
NA
NA
39
NA
NA
0.42
NA
NA
NA
ND
ND
NA
NA
NA
NA
NA
GP-4
02/04/14
CCP
10-12 it
NA
NA
59
2,900
NA
NA
ND
NA
ND
20
20
NA
NA
NA
11
NA
NA
0.51
NA
NA
NA
5.8
ND
NA
NA
NA
NA
NA
02/04/14
CCP
4-6 ft
NA
NA
72
2,800
NA
NA
ND
NA
ND
19
19
NA
NA
NA
9.5
NA
NA
0.33
NA
NA
NA
2.6
ND
NA
NA
NA
NA
NA
GP-5
04/03/19
CCP
4-6 ft
NA
NA
95.9
2,350
5.46
NA
<0.956
NA
0.836 J
12.3
13.1
7.05
50.9
NA
NA
NA
34.7
1.2
NA
11.1
NA
12
NA
NA
325
NA
NA
NA
04/03/191"
CCP
4-6 ft
NA
NA
95.9
2,630
6.99
NA
<0.931
NA
0.712 J
16.2
16.9
10.3
62.5
NA
NA
NA
53.4
0.39
NA
17.1
NA
13
NA
NA
308
NA
NA
NA
GP-6
02/04/14
CCP
9-11 ft
NA
NA
65
850
NA
NA
ND
NA
ND
19
19
NA
NA
NA
27
NA
NA
11
NA
NA
NA
4.1
ND
NA
NA
NA
NA
NA
04/04/19
CCP
9-10 ft
NA
NA
6.73
178
0.758
NA
0.1181
NA
<1.11
10.0
10
5.18
11
NA
NA
NA
687
0.050
NA
6.24
NA
0.88
NA
NA
21.7
NA
NA
NA
GP-7
02/04/14
CCP
10-12 ft
NA
NA
55
1,700
NA
NA
ND
NA
ND
19
19
NA
NA
NA
11
NA
NA
0.26
NA
NA
NA
4.3
ND
NA
NA
NA
NA
NA
GP-6
02/04/14
CCP
11-15ft
NA
NA
54
41100
NA
NA
ND
NA
ND
20
20
NA
NA
NA
9.2
NA
NA
0.29
NA
NA
NA
4.5
ND
NA
NA
NA
NA
NA
GP-11
02/04/14
CCP
4-6 ft
NA
NA
16
450
NA
NA
ND
NA
ND
16
16
NA
NA
NA
23
NA
NA
0.35
NA
NA
NA
ND
ND
NA
NA
NA
NA
NA
GP-12
02/04/14
CCP
2-4 ft
NA
NA
52
2,000
NA
NA
ND
NA
ND
19
19
NA
NA
NA
14
NA
NA
0.28
NA
NA
NA
2.1
ND
NA
NA
NA
NA
NA
HH-1
11/03/16
Soil
0-1 ft
NA
<0.29
5.9
120
1.00
NA
<0.29
NA
0.45
20.55
21
7.9
25
NA
27
NA
350
0.052
NA
8.8
NA
0.69
NA
NA
31
<0.58
48
50
11/03/161"
Soil
0-1 ft
NA
<0.35
34
110
0.79
NA
<0.35
NA
0.54
19.46
20
8.4
17
NA
18
NA
360 BH
0.067
NA
12
NA
<0.71
NA
NA
30
<0.71
41
35
HH-2
11/03/16
Soil
0-1 ft
NA
<0.29
4.9
140
0.93
NA
<0.29
NA
0.43
13.57
14
12
21
NA
30
NA
260
0.085
NA
5.9
NA
1.0
NA
NA
25
<0.58
48
43
HH-3
11/03/16
Soil
0.1 ft
NA
<0.33
9.9
200
1.30
NA
<0.33
NA
0.46 J
17.54
18
7.8
31
NA
24
NA
350
0.076
NA
8.9
NA
2.4
NA
NA
36
<0.65
53
100
HH-4
11/03/16
Soil
0.1 ft
NA
<0.28
2.4
72
1.00
NA
<0.28
NA
0.50
44.5
45
16
37
NA
2.3
NA
630
<0.023
NA
33
NA
<0.56
NA
NA
42
0.60
73
70
HH-5
11/03/16
Soil
0-1 ft
NA
<0.30
2.4
73
0.75
NA
<0.30
NA
�0.14
23
23
8.4
19
NA
9.3
NA
410
<0.025
NA
14
NA
1.2
NA
NA
23
<0.60
39
51
MW-7
11/01/16
Soil
0-1 ft
NA
<0.30
2.6
67
0.87
NA
<0.30
NA
0.89
9.11
10
3.9
180
NA
7.6
NA
100
0.030
NA
2.9
NA
<0.59
NA
NA
6.7
<0.59
61
46
Embankment
Samples
S-7
01/31/14
CCP
0-4ft
NA
NA
44
2,500
NA
NA
ND
NA
1.4
27.6
29
NA
NA
NA
11
NA
NA
0.44
NA
NA
NA
4.5
ND
NA
NA
NA
NA
NA
HH-9
04/03/19
CCP
0-1 ft
NA
NA
3.37
131
0.398 J
NA
0.178 J
NA
<1.29
12.7
12.7
5.97
14.5
NA
NA
NA
260
0.31
NA
3.59
NA
0.722
NA
NA
33.2
NA
NA
NA
HH-10
04/03/19
CCP
0.1 ft
NA
NA
60.3
2,970
5.14
NA
0.162 J
NA
<1.60
13.8
13.8
9.84
51.3
NA
NA
NA
73.3
0.22
NA
17.1
NA
5.04
NA
NA
269
NA
NA
NA
HH-11
04/03/19
CCP
0-1 ft
NA
NA
42.5
3,260
5.9
NA
0.220 J
NA
0.467 J
18.7
19.2
13.4
55.3
NA
NA
NA
113
0.43
NA
23.5
NA
9.05
NA
NA
234
NA
NA
NA
Lower
Level Samples
SS-7
02/18/16
Soil
2-12 in
NA
ND
3.1
B4
0.60
ND
ND
NA
NA
NA
14
6.9
15
NA
13
NA
500
0.038
ND
5.9
NA
ND
ND
NA
31
ND
37
37
HH-8
10/27/16
Soil
0-1 ft
NA
<0.3C
3.6
100
1.00
NA
<0.30
NA
<0.35
19
19
12
29
NA
18
NA
570
0.036
NA
9.0
NA
<0.60
NA
NA
28
<0.60
52
54
MW-6
11/02/16
Soil
0-1 ft
NA
<0.26
2.9
38
0.61
NA
<0.26
NA
0.21 J
9.79
10
9.5
23
NA
12
NA
570
0.082
NA
B.2
NA
1.0
NA
NA
22
0.81
31
77
SED-3A
04/05/19
Soil
0-1 ft
NA
NA
3.45
33.9
0.418 J
NA
<0.582
NA
<1.16
17.4
17.4
16.5
6.97
NA
NA
NA
560
<0.0054
NA
5.82
NA
0.237 J
NA
NA
9.6
NA
NA
SED-5A
04/04/19
Soil
0-1 ft
NA
NA
1.25
13.5
0.156 J
NA
<0.571
NA
0.352 J
13.2
13.6
5.95
39.1
NA
NA
NA
243
0.0071
NA
4.38
NA
<0.571
NA
NA
10.9
NA
NA
NA
SED-6
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
2.41
49.1
0.313 J
NA
0.122 J
NA
<1.25
12.0
12
7.01
14.3
NA
NA
NA
423
0.063
NA
4.66
NA
1.01
NA
NA
15.2
W
NA
NA
SED-9
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
1.16
33.8
0.199 J
NA
<0.660
NA
0.461 J
21.6
22.1
9.11
10.1
NA
NA
NA
431
0.013
NA
6.68
NA
<0.660
NA
NA
16.7
W
NA
NA
SED-10
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
1.29
24.4
0.118 J
NA
0.221 J
NA
0.418 J
12.0
12.4
4.43
10.8
NA
NA
NA
195
0.037
NA
4.03
NA
0.273 J
NA
NA
8.1
W
NA
NA
SED-12
08/27/19
Drainage Pathway Soil
0-2 in
NA
NA
4.73
102
0.765 J
NA
0.214 J
NA
<1.68
27.6
27.6
6.17
23.1
NA
NA
NA
341
0.042
NA
7.69
NA
0.961
NA
NA
25.4
W
NA
NA
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
3.97
122
0.499 J
NA
0.204 J
NA
<1.74
9.45
9.45 B
6.04
19.7
NA
NA
NA
319
0.077
NA
4.95
NA
1.36
NA
NA
32.8
W
NA
NA
SED-13
08/27/19
Drainage Pathway Soil
0-2 in
NA
NA
12.4
958
1.56
NA
0.284 J
NA
<2.03
29.4
29.4
13.9
38.9
NA
NA
NA
538
0.12
NA
1942
NA
3.07
NA
NA
125
W
NA
NA
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
14.5
724
1.1
NA
0.171 J
NA
<1.58
14.0
14
7.58
27.1
NA
NA
NA
563
0.075
NA
8.73
NA
1.69
NA
NA
70.5
W
NA
NA
SED-18
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
4.53
137
0.534 J
NA
<0.689
NA
<1.38
18.7
18.7
11.1
28.2
NA
NA
NA
464
0.051
NA
9
NA
1.85
NA
NA
32.6
W
NA
NA
SED-19
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
1.55
20.0
0.161 J
NA
<0.588
NA
0.435 J
21.7
22.1
7.98
8.38
NA
NA
NA
266
0.0073
NA
4.94
NA
0.334 J
NA
NA
15
W
NA
NA
SED-20
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
0.792
31.4
0.152 J
NA
<0.687
NA
<1.37
5.76
5.76 B
4.5
9.1
NA
NA
NA
360
0.012
NA
2.19
NA
0.263 J
NA
NA
11.5
W
NA
NA
SED-21
04/05/19
Drainage Pathway Soil
2-6 in
NA
NA
1.12
25.9
0.149 J
NA
<0.591
NA
<1.18
20.9
2049
4.44
6.58
NA
NA
NA
221
0.011
NA
2.7
NA
0.286 J
NA
NA
12.8
W
NA
NA
Excavation G-1
04/16/20
Soil
2-3 ft
NA
NA
3.68
58.8
<3.08
NA
<1.23
NA
0.478 J
20.0
20.5
5.73
14.5
NA
NA
NA
193
0.052
NA
6.94
NA
<3.08
NA
NA
6.2
NA
NA
NA
Excavation H-1
05/11/20
Soil
1-2 ft
NA
NA
1.16
37.2
<2.76
NA
<1.10
NA
<1.10
20.1
20.1
10.7
15.3
NA
NA
NA
412
<0.0442
NA
5.80
NA
<2.76
NA
NA
29.3
NA
NA
NA
Excavation H-2
05/11/20
Soil
1-2 ft
NA
NA
1.93
100
<3.25
NA
<1.30
NA
0.578 J
43.8
44.4
19.1
59.2
NA
NA
NA
265
0.0494 J
NA
16.2
NA
1.58 J
NA
NA
56.8
NA
NA
NA
Excavation H-3
05/11/20
Soil
1-2 ft
NA
NA
2.41
71.0
<3.28
NA
<1.31
NA
0.410 J
40.2
40.6
14.1
43.4
NA
NA
NA
251
0.0485 J
NA
12.5
NA
1.46 J
NA
NA
58.1
NA
NA
NA
Excavation H-4
05/11/20
Soil
2-3 ft
NA
NA
2.03
67.1
<3.04
NA
<1.22
NA
0.388 J
25.8
26.2
20.8
24.0
NA
NA
NA
NA
NA
558
0.0237 J
<0.0486
NA
NA
7.81
6.77
NA
NA
<3.04
<3.04
NA
NA
NA
NA
38.1
32.2
NA
NA
NA
NA
NA
NA
Excavation H-5
05/11/20
Soil
1-2 ft
NA
NA
1.10 J
74.5
<3.04
NA
<1.22
NA
0.497 J
21.1
21.6
8.25
16.9
NA
Excavation H-6
05/11/20
Soil
1-2 ft
NA
NA
1.02 J
96.0
<297
NA
<1.19
NA
<1.19
14.9
14.9
7.57
10.7
NA
NA
NA
557
0.0222 J
NA
4.03
NA
<2.97
NA
NA
20.5
NA
NA
NA
Excavation H-7
11/09/20
Soil
0-1 ft
NA
NA
1.10 J
73.7
0.767 J
NA
<1.22
NA
<1.22
8.04
8.04
3.68
15.0
NA
NA
NA
233
0.022
NA
4.63
NA
0.479 J
NA
NA
9.6
NA
NA
NA
Excavation 1-1
04/08/20
Soil
1-2 ft
NA
NA
2.91
67.2
<2.77
NA
<1.11
NA
0.457 J
26.2
26.7
13.0
18.3
NA
NA
NA
594
0.042
NA
8.25
NA
<2.77
NA
NA
26.3
NA
NA
NA
Excavation I-2
Excavation I-3
04/08/20
04/08/20
Soil
Soil
1-2 ft
1-2 ft
NA
NA
NA
NA
2.18
74.1
61.5
<2.85
<2.88
NA
NA
<1.14
<1.15
NA
NA
0.313 J
0.387 J
23.3
13.1
23.6
13.5
12.0
21.4
NA
NA
NA
544
0.022
NA
8.70
NA
<2.85
NA
NA
17.2
NA
NA
NA
9.23
19.5
NA
NA
NA
419
0.019
NA
6.02
NA
<2.88
NA
NA
13.3
NA
NA
NA
Bart & Ili,kmaa, PC

Table A-1 (page 2 of 2)
Summary of Post-IRM Soil Analytical Data
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
E
Sample
c
E
Sample ID
Sample Date
Material Sampled
Depth
o
.o
E
(Soil or CCP)
(ft or in
E
E
E
bgs)
E
3
E
_
_
-
3
E
E
E
E
E
_12
c
T
-2
-
m
m
o
1,
-
9
8
3
E
E
E
E
Sit. -Specific
BS
NA
ND
3.015
87.86
0.929
NA
0.313
NA
5.725
70.2
70.2
36.31
77.3
NA
59.11
NA
1,149
0.256
NA
19.49
NA
2.503
NA
NA
43.19
0.981'
227
230
PSRG - Protection of Groundwater')
110,000
0.90
5.8
580
63
45
3.0
NS
3.8
360,000
INS
0.90
700
150
270
NS
65
1.0
7.1
130
INS
2.1
3.4
INS
1,500
0.28
350
1,200
PSRG- Residential Health -based')
16,000
6.3
0.68
3,100
31
3,100
14
NS
0.31
23,000
INS
4.7
630
11,000
1 400
NS
380
2.3
1 78
310
1 INS
78
1 78
INS
1 9,400
1 0.16
78
4,700
PSRG - Industrial/Commercial Health -based')
1 230,000
1 93
1 3.0
1 47,000
470
1 47,000
1 200
1 INS
1 6.5
1 350,000
1 INS
1 70
1 9,300
160,000
1 800
1 INS
1 5,600
1 9.7
1 1,200
4,700
1 INS
1,200
1 1,200
INS
140,000
1 2.3
1,200
70,000
Background
Samples
MW-5
11/02/16
Soil
0-1 It
NA
<0.30
2.1
76
0.99
NA
<0.30
NA
0.43 J
17.57
18
27
49
NA
4.0
NA
710
<0.023
NA
5.0
NA
<0.59
NA
NA
25
<0.59
190
47
(background)
11/02/16
Soil
6-7 It
NA
<0.27
1.4
61
0.60
NA
<0.27
NA
0.81
38.19
39
19
18
NA
0.55
NA
940
<0.020
NA
20
NA
<0.53
NA
NA
29
2.3
67
75
11/03/16
Soil
0-1 It
NA
<0.28
1.9
36
0.39
NA
<0.28
NA
0.87
17.13
18
6.3
16
NA
25
NA
310
0.033
NA
5.4
NA
1.6
NA
NA
15
<0.57
34
43
BG-1 (background)
11/03/16
Soil
2-3ItNA
<0.29
2.3
45
0.48
NA
<0.29
NA
<0.12
19
19
7.3
18
NA
43
NA
440
0.280
NA
6.2
NA
1.6
NA
NA
15
<0.57
35
49
11/03/16
Soil
0-1 it
NA
<0.28
1.9
45
0.50
NA
<0.28
NA
0.84
16.16
17
7.4
18
NA
32
NA
410
0.045
NA
4.9
NA
1.1
NA
NA
14
<0.56
35
44
BG-2 (background)
11/03/16
Soil
2-3ItNA
<0.27
1.9
52
0.53
NA
<0.27
NA
0.70
23.3
24
7.5
20
NA
26
NA
450
0.038
NA
7.9
NA
1.7
NA
NA
19
<0.55
37
45
BG-3
11/03/16
Soil
0-1 It
NA
<0.30
1.7
44
0.43
NA
<0.30
NA
0.21 J
23.3
16
7.5
15
NA
25
NA
410
0.024
NA
5.1
NA
1.4
NA
NA
46
<0.60
37
40
(background)
11/03/16
Soil
2-3ItNA
<0.27
2.2
56
0.54
NA
<0.27
NA
0.88
21.12
22
7.5
18
NA
29
NA
410
0.040
NA
5.2
NA
1.2
NA
NA
19
<0.53
40
46
BG4
11/03/16
Soil
0-1 it
NA
<0.29
1.7
50
0.50
NA
<0.29
NA
<0.13
19
19
9.5
16
NA
22
NA
450 BH
0.026
NA
6.0
NA
<0.59
NA
NA
16 A
<0.59
53
50
(background)
11/03/16
Soil
2-3 It
NA
<0.33
2.0
53
0.52
NA
0.38
NA
0.50 J
22.5
23
11
23
NA
21
NA
460 BH
0.054
NA
8.5
NA
<0.65
1 NA
NA
19
<0.65
51
230
BG-6
04/03/19
Soil
0-1 ft
NA
NA
2.0501
64.4
0.625
NA
0.177 J
NA
5.34
39.4
44.7
14.4
26.4
NA
NA
NA
448 J6
0.022
NA
12.8
NA
0.562 J
NA
NA
17
NA
NA
NA
(background)
04/04/19
Soil
2-3 ft
NA
NA
2.29
66.3
0.507 J
NA
0.139 J
NA
<1.19
22.9
22.9
14.7
32.3
NA
NA
NA
467
0.032
NA
7.78
NA
0.828
NA
NA
16.8
NA
NA
NA
BG-7
04/03/19
Soil
0-1 ft
NA
NA
1.97
52.7
0.410 J
NA
0.136 J
NA
<1.16
70.2
70.2
18.9
36.4
NA
NA
NA
813
0.025
NA
12.8
NA
0.543 J
NA
NA
22.6
NA
NA
NA
(background)
04/04/19
Soil
2-3 ft
NA
NA
77.9
0.430 J
NA
0.108 J
NA
<1.16
27
27
16.3
32.5
NA
NA
NA
548
0.023
NA
6.2
NA
0.502 J
NA
NA
24.3
NA
NA
NA
BG-8
04/03/19
Soil
0-1 ft
NA
NA
1.8
52.4
0.370 J
NA
0.0951 J
NA
<1.14
24.5
24.5
21.8
62.8
NA
NA
NA
759
0.0072
NA
9.04
NA
0.485 J
NA
NA
24.4
NA
NA
NA
(background)
04/04/19
Soil
23It
NA
NA
1.66
47.6
0.293 J
NA
0.0918 J
NA
<1.14
21.7
21.7
23.5
60.2
NA
NA
NA
732
<0.0067
NA
7.86
NA
0.306 J
NA
NA
25.1
NA
NA
NA
Notes:
Concentrations reported in milligrams per kilogram (mg/kg).
1) Site -Specific Background Screening Value (BSV) represents 95 % upper threshold level (UTL) with 95 % coverage calculated using EPA PmUCL 5.1.
'Insufficient data to calculate 95 % UTL; therefore, site -specific BSV indicates 2x mean concentration with non -detect concentrations calculated as halt the reporting limit.
2) North Carolina Department of Environmental Quality (DEQ) Preliminary Soil Remediation Goals (PSRGs) (June 2021)
3) Duplicate sample taken
Bold denotes concentration above or equal to Protection of Groundwater PSRG and site -specific BSI
Shading indicates concentration above or equal to Residential PSRG and site -specific BSV.
Underlining indicates concentration above or equal to Industrial/Commercial PSRG and site -specific BS'
ND = Not Detected; NA = Not Analyzed; NS = Not Specified; NC = Not Calculated
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
01 = Analyte failed the method required serial dilution lest and/or subsequent post -spike criteria. These failures indicate matrix interference.
J6 = The sample matrix interfered with the ability to make any accurate determination; spike value is low.
SH - Method blank greater than one-half laboratory reporting limit, but sample concentration greater than 10x the method blank.
A = Continuing Calibration Verification standard recovery (82%) is less than the lower control limit (90% ). Result has possible low bias.
Excavated sample locations are not shown in table.
Analytical Methods
Metals by EPA Method 6010C or 6020E
Hexavalent Chromium by EPA Method 7196 or 7199 (Phase II RI and April 2019 Data Gap Samples)
Mercury by EPA Method 7471 B
lima & Ili, km n, PC

Table A-2 (page 1 of 1)
Summary of Stream Sediment Analytical Data
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
E
E
E
o
;=
E
Sediment Sampling Point ID
Sample Date
2
'2
0
U
c
U
C
�
�'
7
E
7
O
E
'�
E
_
7
E
CO
>
COi�
N
L
U
"
i
N
U
N
C
=
�
L
L
X
>
(6
O
-0
U
0.
O
f6
f0
U
Y
U
O
f0
C
CO
U
C
(6
(6CO
U
L
N
E
E
C
(n
C
Site -Specific BSV(1)
ND
2.74
38.4
0.48
ND
0.79
69.5
70
16.388
13.8
7.1
759
0.0078
9.92
0.409
16.9
ND
37
34
PSRG - Protection of Groundwater(2)
0.90
5.8
580
63
3.0
3.8
360,000
NS
0.90
700
270
65
1.0
130
2.1
1,500
0.28
350
1,200
PSRG - Residential(2)
6.3
0.68
3,100
31
14
0.31
23,000
NS
4.7
630
400
380
2.3
310
78
9,400
0.16
78
4,700
PSRG - Industrial/Commercial(2)
93
3.0
47,000
470
200
6.5
350,000
NS
70
9,300
800
5,600
9.7
4,700
1,200
140,000
2.3
1,200
70,000
10/27/16
1.2
12
0.24 J
22.76
23
3.9
4.2
4.0
180
3.8
6.9
19
19
SED-1 (Upstream)
04/05/19
1.9501
38.4 J6
0.249 J
0.428 J
65.0
65.4 J3, J6
7.63
8.42
449 J6
0.0078
7.1
0.409 J
8.4
10/27/16
2.1
20
0.48
36
36
7.8
8.0
7.1
330
7.2
11
37
34
10/27/16(3)
2.5
17
0.45
49
49
6.5
9.1
6.7
290
6.0
12
35
31
SED-2 (Upstream)
04/05/19
2.74
29.6
0.305 J
0.796 J
56.3
57.1
20.9
13.8
811
0.0053 J
9.16
0.306 J
16.9
04/05/19(3)
2.02
17.4
0.222 J
0.546 J
69.5
70
7.29
6.79
347
0.0051
9.92
0.237 J
8.8
10/27/16
1.6
21
0.37
30
30
6.2
7.4
6.9
220
6.8
12
29
35
SED-3 (Adjacent)
04/05/19
1.36
16.4
0.111 J
0.670 J
13.5
14.2
5.18
20.2
225
0.0054 J
4.81
9.2
10/27/16
1.2
8.4
34
34
3.5
5.2
3.5
130
5.0
6.4
16
20
SED-4 (Adjacent)
04/05/19
2.35
20.3
0.191 J
0.456 J
63.8
64.3
7.26
8.39
293
0.0080
10.5
0.344 J
30.7
10/27/16
1.4
44
0.41
51
51
9.5
8.6
22
860
5.3
13
35
32
SED-5 (Downstream)
04/04/19
1.82
24.3
0.233 J
0.595 J
16.8
17.4
5.9
8.86
399
4.86
6.2
SED-6 (Downstream)
04/04/19
1.96
17.3
0.247 J
0.517 J
24.9
25.4
6.57
9.25
308
0.0058
7.15
8.4
SED-7 (Downstream)
04/04/19
1.35
16.4
0.179 J
0.995 J
59.4
60.4
6.47
6.77
262
0.0025 J
9.04
8.1
Notes
Concentrations reported in milligrams per kilogram (mg/kg).
1) Site -Specific Background Screening Value (BSV) indicates two times the mean detected background concentration or maximum detected background concentration, whichever is smaller.
2) North Carolina Department of Environmental Quality (DEQ) Preliminary Soil Remediation Goals (PSRGs) (July 2021)
3) Duplicate sample taken.
Bold denotes concentration above or equal to Protection of Groundwater PSRG and site -specific BSVs.
Shading indicates concentration above or equal to Residential PSRG and site -specific BSVs.
Underlining indicates concentration above or equal to Industrial/Commercial PSRG and site -specific BSVs.
ND - Not Detected; NA - Not Analyzed; NS - Not Specified
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
01 = Analyte failed the method required serial dilution test and/or subsequent post -spike criteria. These failures indicate matrix interference.
J3 = The associated batch QC was outside the established quality control range for precision.
J6 = The sample matrix interfered with the ability to make any accurate determination; spike value is low.
Analytical Methods:
Metals by EPA Method 6010C, 6020A, or 6020B
Mercury by EPA Method 7470A
Hexavalent Chromium by EPA Method 7199A
https://harthick.sharepoint.com/sites/MasterFiles-1 /Shared Documents/AAA-Master Projects/Town of Chapel Hill (TCH)/TCH-009 -Police Station -Remedial Services/Risk Assessment/App A Historical Data/A-1 Historical Data Tables Hart & Hickman, PC

Table A-3 (page 1 of 1)
Summary of Surface Water Analytical Data
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
E
vE
3
£
O
Surface Water Sampling Point ID
Sample Date
_
c
s
E
C
U
£
2
N
E
N
EO
y
m`
>0
C
-o
C
a
N
l6
O
O
O
N
E
E
I E
N
O
S
Site -Specific BSV
NA
ND
0.44
27
ND
ND
NA
ND
ND
0.53
0.16
1.2
ND
ND
NA
22.2
ND
0.33
NA
0.11
100
ND
NA
ND
ND
ND
54,000
NC 2B Standard1�1
NS
NS
10(t)
1,000(t)
6.5
0.27
NS
11
45.08
NS
NS
5.33
NS
1.29
NS
NS
0.012(t)
25(t)
NS
5(t)
NS
0.06
NS
NS
NS
70.07
NS
BC-1 (Upstream)
2/5/2014
24
ND
ND
ND
ND
NA
NA
NA
ND
NA
NA
ND
ND
NA
NA
NA
NA
NA
SW-1
11/3/2016
<10
27
<1.0
N
<0.74
NA
<5.0
<5.0
<10
<0.2
<5.0
NA
<10
<0.2
ci
<20
100
NA
<10
<5.0
<30
N..
(Upstream)
4/5/2019
1
0.44
23.1
<0.080
Nt
NA
NA
0.53
0.16
1.2
NA
NA
NA
22.2
<0.20
0.29 J
0.096 J
85.3
NA
NA
NA
NA
54,000
SW-2
11/3/2016
<10
27
<1.0
<0.74
<5.0
<5.0
<10
<0
<5.0
NA
11
<0.2
<10
NA
<20
100
NA
"^
<5.0
<30
NA
(Upstream)
4/5/2019
0.42
23.2
<0.080
iIA
NA
0.45 J
0.16
1.1
NA
NA
NA
21.2
<0.20
0.33 J
NA
0.11 J
85.5
NA
NA
NA
53,600
BC-2 (Bolin Creek at Site)
6/20/2013
290
0.90
27
ND
16,000
ND
0.37
2.6
860
0.50
5,300
100
r,
1.2
2,300
ND
N
7,800
NA
2/5/2014
ND
24
ND
NA
ND
ND
NA
"'A
NA
NA
NA
ND
NA
ND
(`
NA
NA
11/3/2016
'0
27
<1.0
NA
<0.74
<5.0
<5.0
<0.2
NA
34
<0.2
NA
<20
100
NA
NA
SW-3(Adjacent)
11/3/2016°
27
<1.0
NA
I
<0
33
<(
<20
110
NA
<1i
r
4/5/2019
0.45
25.7
<0.10
<0.080
NA
NA
0.62
0.26
2.8
N,
37.4
<0.20
0.50
0.11 J
88.8
NA
NP
55,900
11/3/2016
<10
27
<2.0
<1.0
NA
<0.74
<5.0
<10
<0
25
<0.2
<10
<20
110
NA
<1i
NA
SW-4 (Adjacent)
4/5/2019
0.42
23.6
<C
<0.080
NA
r
NA
<
0.14
1.0
N,
24.6
<0 --
0.26 J
N
0.10 J
89.1
NA
NA
57,100
4/5/2019°
0.41
23.7
<(
<0.080
NA
NA
<i
0.14
0.98
N,
24.8
<0
0.26 J
N
0.088 J
87.7
NA
P
54,300
11/3/2016
<10
26
<
<1.0
NA
<.
<5.0
<10
<0
24
<(,
I <10
N
<20
100
NA
NA
SW-5 (Downstream)
4/4/2019
0.40
16.9
<0.10
<0.080
NA
NA
<0.50
0.14
0.88
N,
19.5
<0.20
0.21 J
NA
0.12 J
81.8
NA
53,400
SW-6 (Downstream)
4/4/2019
0.40
16.9
<0.10
<0.080
NA
NA
<0.50
0.14
0.84
N,
18.7
<0.20
0.21 J
NA
0.11 J
81.3
NA
53,400
SW-7 (Downstream)
4/4/2019
0.42
18.4
<1
<0.080
NA
<0.50
0.16
1.1
N
23.1
<0
0.23 J
N
0.10 J
86.7
NA
54,400
4/5/2019
0.40
32.1
<
<0.080
NA
0.73
0.36
3.2
N
29.5
<0
0.62
N
0.11 J
69.9
NA
31,400
SW-21 (Drainage Pathway)
4/5/20195
0.15
18.3
<0.080
IA
<0.50
0.094 J
3.1
N
9.3
<0
0.43 J
N
).50
43.5
NA
N,
22,200
Notes:
Concentrations reported in micrograms per liter (Ng/L).
1) Site -Specific Background Screening Value (BSV) indicates two times the mean detected background concentration or maximum detected background concentration, whichever is smaller.
2) North Carolina Surface Water Quality Standard (NC 2B Standard) adopted per 15A NCAC 2B Section .0100. Unless otherwise noted, values are the lowest of the Freshwater, Water Supply, and Human Health values because Boli
Creek is a WS V classification surface water. Value shown is the lower of the acute versus chronic, where applicable.
3) 2B Standards derived using site -specific hardness data for surface water samples SWA through SW-7 and the DEQ Hardness -Dependent Metal Calculator dated July 26, 2021. Mean hardness for these samples was 54.5 mg/L.
4) Duplicate sample taken.
5) Sample was field filtered.
Bold denotes concentration above NC 2B Standard and site -specific BSV.
ND = Not Detected; NA = Not Analyzed; NS = Not Specified
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration
(t) = Based upon measurement of total recoverable metal. See 15A NCAC 02B .0211 for more information.
Analytical Methods:
Metals by 6010C, 6020A, or 6020B
Mercury by 7470A
Hexavalent chromium by 7199A
Total hardness by Standard Method 2340B
Hart & Hickman, PC

Table A-4 (page 1 of 1)
Summary of Well Construction and Groundwater Elevation Data
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
Well ID
Permanent or
Temporary
Date Installed
Date
Abandoned
Drilling Method
Well
Material
Screen
Slot Size
(in)
Total
Depth
(ft bls)
Screened
Interval
TOC
Elevation
(ft)
November 9, 2016
April 3,
2019
Sepember 26, 2019
February 12, 2020
Depth to
Water (ft bls)
Groundwater
Elevation (ft)
Depth to
Water (ft bls)
Groundwater
Elevation (ft)
Depth to
Water (ft bls)
Groundwater
Elevation (ft)
Depth to
Water (ft bls)
Groundwater
Elevation (ft)
MW-1
Permanent
4/29/2013
N/A
DPT
2" PVC
0.01
40
30-40
346.12
35.48
310.64
30.90
315.22
35.67
310.45
35.22
310.90
MW-1A
Permanent
9/24/2019
N/A
Sonic
2" PVC
0.01
40
25-40
345.96
--
--
--
--
31.43
314.53
30.27
315.69
MW-2
Temporary
6/20/2013
6/20/2013
HA
Unknown
Unknown
8
Unknown
--
--
--
--
--
--
--
--
--
MW-3
Permanent
1/27/2014
1/7/2015
Auger
2" PVC
0.01
11
6-11
--
--
--
--
--
--
--
--
--
MW-4
Permanent
1/27/2014
1/6/2015
Auger
2" PVC
0.01
9.2
4.2-9.2
--
--
--
--
--
--
--
--
--
MW-3A
Permanent
5/12/2015
N/A
Air Rotary
2" PVC
0.01
16
1-16
298.10
5.91
292.19
2.79
295.31
7.14
290.96
1.34
296.76
MW-4A
Permanent
5/14/2015
N/A
Air Rotary
2" PVC
0.01
19
4-19
298.00
6.72
291.28
3.20
294.80
7.83
290.17
2.22
295.78
MW-5
Permanent
11/2/2016
N/A
Air Rotary
2" PVC
0.01
27.5
17.5 - 27.5
369.33
9.27
360.06
7.03
362.30
10.24
359.09
9.67
359.66
MW-6
Permanent
11/2/2016
N/A
HSA
2" PVC
0.01
17.5
7.5 - 17.5
315.39
9.92
305.47
7.42
307.97
10.54
304.85
6.87
308.52
MW-7
Permanent
11/2/2016
N/A
Air Rotary
2" PVC
0.01
69.5
59.5 - 69.5
339.54
46.97
292.57
43.58
295.96
47.05
292.49
45.09
294.45
MW-8
Permanent
9/24/2019
N/A
Sonic
2" PVC
0.01
44.5
29.5-44.5
343.89
--
--
--
--
40.16
303.73
38.21
305.68
MW-9
Permanent
9/24/2019
N/A
Sonic
2" PVC
0.01
45.0
30-45
339.04
--
--
--
--
26.92
312.12
25.47
313.57
TMW-10
Temporary
9/24/2019
9/24/2019
Sonic
2" PVC
0.01
40.0
25-40
349.35
--
--
--
--
27.23*
322.12'
--
--
MW-11 D
Permanent
2/11/2020
N/A
HSA / Air Rotary
2" PVC
0.01
56.0
46-56
339.29
--
--
--
--
--
--
31.85
307.44
Notes:
MW-1, MW-3A, MW-4A, MW-5, MW-6, and MW-7 were surveyed by CE Group on December 8, 2016.
MW-1A, MW-8, MW-9, and TMW-10 were surveyed by H&H on September 26, 2019.
MW-11 D was surveyed by H&H on March 3, 2020.
ft = feet; bls = below land surface; in = inches
DPT = Direct Push Technology; HA = Hand Auger; HSA = Hollow Stem Auger
TOC = Top of Casing; -- = Not Specified; N/A = Not Applicable
* = Depth to water gauged on September 24, 2019.
Hart & Hickman, PC

Table A-5 (page 1 of 1)
Summary of Groundwater Analytical Data
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
Monitoring Well
ID
Sample Date
£
.c
x
-
c
-
o
E
c
0
°�
``
E
a
�_
Z
n
o
3
-Eo
m
E
"
m
E
E
o
cti
..
>
x
s
E
o
t
aci
>
E
E
cti
o
L
a
0
d
n
0
c
o
m
m
E
m
m
E
m
m
m
E
`m
E
.o
o
E
_
-
?
n
o
_m
°�
>
E
a
o
3
o
E
m
E
m
m
_
2L Standard or IMAC
NS
NS
NS
1
10
700
4
700
2
NS
NS
NS
10
1
1,000
300
15
NS
50
1
NS
100
NS
20
20
NS
NS
0.2
0.3
1,000
MW-5
11/9/2016
3.8
0.5
<10
51
<2.0
0.27J
NA
580
23
N,
190
0.39J
<30
(Background)
4/3/2017
8.2
NA
INA
N,
NA
NA
NA
NA
NA
NA
N
-
NA
NA
5/3/2013
NA
NA
5,600
5.4
85
1,100
1.6
0.17
110,000
N
15
15
25
6,500
5.8
25.000
7,600
12
7,600
2.5
NL,
34,000
1.0
38
52
2/18/2016
NS
NA
NA
JD
67
1,300
11.0
ND
.ND
NA
N,
NA
100
78
170
NA
36
9,600
0,26
ND
58
ND
ND
2,900
ND
260
330
li
2/18/2016'
NS
NA
NA
JD
52
1,100
8.8
ND
ND
NA
N,
NA
86
61
130
NA
29
.A
9,000
0.21
ND
46
ND
ND
NA
2,700
ND
200
260
11/10/2016
475.0
NA
NA
0.5
19
470
4.1
NA
0.15 J
NA
N,
NA
31
32
57
NA
10
NA
8,600
,Y
NA
21
23
NA
NA
2,200
<2.5
92
99
11/10/2016'
JA
NA
NA
0.5
<10
160
0.53 J
NA
<1.0
NA
N
NA
6.0
NA
<5.0
'IA
8,000
<0.2
NA
2.3 J
<20
NA
NA
2,100
<2.5
1.2 J
<30
4/3/2019
7.76
�I
JA
22.9
1,730
<0.10
^
1.8
0.331
NA
r
3,090
NA
0.60
<0.50
NA
'"
4,710
NA
NA
MW-1A
9/26/2019
6.63
NA
JA
10
1,040
<0.50
1.2
<2.5
NA
Nn
2,420
_ -0
NA
0.82J
<2.5
1
6,360
NA
NA
MW-2
6/20/20131
NA
NA
16,000
0.61
8.3
1,100
5.5
0,93
260,000
8.4
23
1,200
13,000
27
47,000
1,200
0.18
NA
70
42,000
18
0.27
52,000
NA
0.48
71
2,200
2/5/2014
NA
JA
ND
160
NA
ND
N,
NA
NA
MW-3
2/5/20142
NA
JA
ND
250
NA
Nf.
24
ND
NI
NA
NA
8/15/20143
1,500
NA
JA
51
830
NA
NA
30
78
NA
30
NA
NA
ND
NI
NA
NA
8/20/20144
13.0
JA
ND
220
NA
23
ND
NI
NA
NA
7/21/2015
5.7
NA
JA
ND
67
NA
520
NA
'D
ND
NA
NA
NA
2/17/2016
1.3
NA
NA
JD
ND
89
ND
N
NA
NL
NA
P.
IA
ND
NI
ND
ND
23
ND
2,400
ND
ND
MI
2/17/20161
1.3
NA
NA
JD
ND
80
ND
ND
NA
NL
NA
ND
IA
23
NL
ND
ND
26
ND
2,100
ND
ND
11/9/2016
1.2
NA
NA
0.5
<10
53
<2.0
NA
<1.L
P'
<10
NA
<
IA
14
<0.2
NA
<10
50
NA
2,400
5.4 J
0.94 J
12 J
11 /9/20162
1.2
NA
"' A
0.5
<10
53
<2l
"' A
-1 r
- 1 ^
"' A
15
' '
NA
<10
52
NA
2,400
5.3 J
0.95 J
<30
4/4/2019
0.00
NA
JA
0.15
68.2
<l,
0,21
0,55
5.8
NA
0.50J
34.2
NA
2,950
.JA
NA
MW-4
2/5/2014
JA
NA
JA
140
6,500
NA
NA
1.7
ND
NA
930
NA
250
NA
1.4
NA
NA
99
ND
NA
NA
8/20/2014"'
10
NA
JA
ND
75
NA
NA
ND
NA
""
""
""
D
NI
NA
NA
7/21/2015
24.7
<`
JA
ND
64
1
ND
ND
I
ND
ND
NL
NA
NA
7/21/2015'
24.7
NA
NA
NA
ND
61
NA
ND
JD
NA
Nf
NA
ND
NA
N.
NA
ND
�A
NL
NA
NA
NA
ND
ND
NA
NA
NA
NA
MI2/18/2016
189.0
NA
NA
ND
ND
26
ND
ND
ND
NA
N,
NA
ND
ND
NL
NA
7.8
NA
49
NC
ND
ND
NA
ND
ND
NA
110
ND
ND
34
2/18/2016'
189.0
NA
NA
ND
ND
33
ND
ND
ND
NA
N,
NA
ND
Nf
ND
NA
8.4
NA
41
ND
ND
ND
NA
ND
ND
NA
78
ND
ND
48
11/9/2016
4.8
NA
NA
�0.5
<10
36
<2.0
NA
<1.0
NA
N,
NA
1.2 J
<10
NA
<5.0
�A
140
<0.2
NA
NA
7.2 J
NA
NA
170
<2.5
<0.15
17 J
4/4/2019
9.43
Nt
NA
<0.10
22.5
0.070 J
NA
<r '
N"
0.063 J
0,63
6.0
'0
NA
1.5
0.82
NA
NA
73
NA
NA
NA
11/9/2016
2.5
N
0.5
<10
340
<2.0
NA
P
29
1.9 J
2,500
NA
22
20
NA
690
<2.5
1.2 J
<30
MW-6
4/3/2017
7.6
NA
NA
JA
NA
NA
NA
<4.8
NA
<10.0
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
4/4/2019
4.48
NA
NA
JA
0.14
283
<0.10
NA
<0."
NA
NA
<0.50
0.33
<0.50
NA
P'
2,210
<0.20
NA
0.20 J
0.12 J
NA
752
NA
NA
4/4/20192
4.48
NA
NIA
JA
0.14
279
<0.10
NIA
<n ns,
NIA
NIA
<n Fr
0.32
0.50 J
NA
2,160
<0.20
NA
0.19 J
0.11 J
NA
736
NA
NA
MW-7
11/14/2016
8.9
<`
0.5
<10
10
<2.0
1.3 J
0.17 J
1.6 J
NA
140
<0.2
NA
1.6 J
<20
N,
42
1.11
26 J
4/3/2019
8.95
<`
JA
0.13
4.5
INA
z0.050
0.72
NA
20.5
<0.20
NA
0.43 J
0.10 J
N,
44.9
JA
NA
MW-8
9/26/2019
7.95
JA
6.1
219
NA
0,51
4.0
0.98
NA
4,880
<0.20
NA
4.1
<0.50
N,
750
NA
NA
9/26/2019
1.74
JA
0.75
394
<0.20
NA
1.5
2.1
NA
5,060
<0.20
NA
0.41 J
1.0
N,
2,160
NA
NA
MW-9
2/12/2020
1.10
377,000
JA
0.78J
369
<0.10
NA
<0.10
118,000
NA
NA
2.3
1.0
NA
NA
26,100
5,430
<0.20
NA
12,400
<1.0
NA
24,900
2,380
NA
NA
2/12/20202
1.10
377,000
JA
0.74J
338
<0.10
NA
<0.10
113,000
NA
NA
2.5
1.1
NA
NA
1 25,600
5,170
<0.20
NA
12,100
<1.0
NA
24,100
2,310
NA
NA
MW-11D
1 2/13/2020
8.59
413,000
JA
1.5
24.1
<0.10
NA
<0.10
45,100
NA
1.7
2.2
NA
NA
1 30,300
14.7
<020
NA
5.5
145,000
0.74J
NA
65,400
604
NA
NA
Notes:
Concentrations reported in micrograms per liter (pg/L), except turbidity which is reported in Nephelometdc Turbidity Units (NTUs).
2L Standard = North Carolina Department of Environmental Quality (DEQ) 15A NCAC 02L.0202 Groundwater Standards (April 2013).
IMAC = Interim Maximum Allowable Concentration
Bold denotes concentration above or equal to the 2L Standard or IMAC and background levels
ND = Not Detected; NA = Not Analyzed; NS = Not Specified
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
'Reported to the method detection limit instead of laboratory reporting limit.
1) Denotes sample labeled as "Well #1" in the lab report associated with the Limited Phase II ESA prepared by Falcon.
2) Denotes duplicate sample taken.
3) Denotes sample labeled as "Well 1" in the lab report associated with the October 3, 2014 letter prepared by Falcon.
4) Denotes filtered sample.
5) An unfiltered sample was also collected from MI on August 20, 2014 and the results were reported in mg/kg-wet, presumably because of the high sediment load. These data are not included in this table.
Analytical Methods:
Metals by EPA Method 6010C, 6020A, or 6020B
Hexavalent Chromium by EPA Method 7196A / SM3500
Mercury by 7470A/245.1
Hart & Hickman, PC

ABOLINWOOD
A
DRIVE
NORTH
Lo
SOUTH
(FT.)
�
(FT.)
370
_—
—
370
360—
—CLAY —.. ... ...—... ...—...
POLICE DEPT.
—360
PARKING LOT
e.
350
�-1�
......:...
� —1� 'fib' — ------ + +—....,...
...
350
—.....—.....—.......... — ....
—.....—.....—..... —.....—.....—..
CCPs+ ...—...
..... _.....—.....——.....—........ —......
.... _.....— . ... —..
—.� ..
.....
FILL MATERIAL :--::
------- ...
.............................................
—... ...
—... ...
...—... ..
340
—I—I —I —I—I—I .;°jp:;. DEBRIS./" SOIL / CCPs.-.—.:
o..—.....—....:—..... .... ....
.....—.....—.....—.....—.....—.
.... .... ..... .... .....
— —... —... ..
— —
�...—.......—...
—. FILLMATERIAL
—...—.......
— —
340
—....—....-- ....
�\.....—.....—.....
—....
CCPs —.
— ... — .... ...—...
----
...—... ...—... CLAY /SILT /SAND..—... ...—...
— ---
— — — —
---------
..
-\.— ..... — ..... — ..... ...
— ..... — ..... — ..... — ..... .......
— — — — —
— — — ======
—
---...... .—. ...... —.
— ..—
++ + + + + + — — — ——
—
—— .. — ..330
.. ......
330
—
—
— — — — — FORMER EROSIONAL
+_ + + + + + +
+ + + +
FILL MATERIAL /CCP
—: '
LAYER
.......
++
+ + + CCP+
_+.— +
+—
++++
—
.—...: .—...
DEBRIS / SOIL / CCPs----++++++
-- ---- --- ---
--- —+
-- BOLIN
..
....+
+ + + ::—
....—— CREEK
—320
320—++++
— — — — —
o=—
+
+++ +++
310
.— ..... —..... .....—.
._—...... .—"—.—"—.—
— — — — — — — — —
— — — — — — BOLIN CREEK
TRAIL
310
+CCPs.
——
/`BEDROCK
—
'
�/
\_
I?
W
300
_ _
300
CIO
7'"Q 7'",O "O—
---SILTY CLAY— 5;
i� i� i� i�
-I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I
i� �\ O
•o -' ' I I —I —I —I —I —I —I —I —I I �' ° 0 0
°
— -
--
290
i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i /i
—I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I
i�
—I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I —I o o
�/
ti
o o 'ooQ o oC
'
290
'o o 000 o
280
280
/—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I'� I'�-1 /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /—I /-1 /—
270
�; �; �; �: �: �; �; �; �; �: �: �; �; �; �: �: �: �; �; /; /: /: /: /; /; /; /: / L,/; /; /; /; /: /: /; /; /; /; /: /: /; /; /; �; �; �: �; �; �; �; �: �:
270
LEGEND
2
2
SOIL BORING DEPICTING SAMPLE INTERVAL
MONITORING WELL DEPICTING SCREEN INTERVAL
320 3 UNCONFINED AQUIFER (FEBRUARY 2020)
SILTY CLAY
_^ FILL MATERIAL / CLAY / SILT / SAND
EEl+ + COAL COMBUSTION PRODUCTS
+++++ (CCPs) - THICKER LAYERS
FILL MATERIAL, DEBRIS AND SOIL WITH
INTERLAYERED AND INTERMIXED CCPs
i PARTIALLY WEATHERED ROCK (PWR)
�\ �\ BEDROCK
NOTES:
1. REFER TO FIGURE 3 OF THIS REPORT FOR CROSS-SECTION
TRANSECT.
2. * INDICATES MONITORING WELL INSTALLED BY FALCON
ENGINEERING, INC.
3. WITH THE EXCEPTION OF TMW-10 (GROUNDWATER ELEVATION
MEASURED AND WELL ABANDONED ON SEPTEMBER 24, 2019),
GROUNDWATER ELEVATIONS MEASURED ON FEBRUARY 12,
2020.
4. GROUNDWATER ELEVATIONS IN FILL (MW-1A, MW-9, AND
TMW-10) APPEAR INDICATIVE OF PERCHED GROUNDWATER.
5. SOME CCP LAYERS CONCEPTUALLY INFERRED FOR
ILLUSTRATION PURPOSES.
20
APPROXIMATE
0 80
SCALE IN FEET
VERTICAL EXAGGERATION = 4X

MONITORING WELL SCREENED
GROUND SURFACE IN PERCHED GROUNDWATER
...—...,.,...—...,.,...—...,�,...—� FILL MATERIALS •-...—...,.,...—...,.,...—...,.,...—.....
—... ...—... ...—... ...—...
...—... ...—... ...—...
• — • . .•—...+ + +
..
. — —.......
+ +
+ +
+...
...—........—... --------..—...
+ + + + ... —... ... ......
+ + + + + + + + + + + + + +
+. +. +. +. +. ++.+.++
...—
...—... ..
—
—.......—.......—.......—..
SMALL VOLUME OF SEEPAGE
FROM
—... - —...
,....—.......—.......—...,....—...
PER CHED: "� "—""� "—"' ......
� "
+
GROUNDWATER TO UNCONFINED AQUIFER
... ............. .......—.......—.......—.......—.......—...
...—.......—..
LEGEND
MONITORING WELL DEPICTING SCREEN INTERVAL
-� UNCONFINED AQUIFER WATER LEVEL
PERCHED GROUNDWATER LEVEL
MONITORING WELL SCREENED
IN UNCONFINED AQUIFER
...........
..............
+ + + + + + + + + + + + + + + + + + + + + +
+ +
+ + + + + + + + + + + + CCPs + + + + + + + + +
+ + + + + + + + + + + + + + + + + + + + + +
+ + + + + + + + + + + + +++++ + + + + + + + + +
+ + + + + + + + + + + + + + + + + + + + + + + +
+ + + + + + + + + + + + + + + + + + + + + + + +
+ + + + + + + + + + + + + + + + + + + + + + + +
+ ...—......—.........
—... ...—... ...—... ...—... --- —... �,...—... ...—... ...—...
—" WATER LEVEL IN PERCHED —
_l FILL MATERIALS
El
COAL COMBUSTION PRODUCTS (CCPs)
rmLOW PERMEABILITY ZONES (EX: CLAY)
PERCHED GROUNDWATER
INFILTRATING PRECIPITATION
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PARTIALLY WEATHERED ROCK (PWR)
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- UNCONFINED AQUIFER
NOT TO SCALE

Appendix B
Summary of Background Screening Values Calculations

Appendix B
Calculation of Background Screening Values (BSVs)
In order to determine whether metals detections are related to source materials or represent
naturally -occurring background levels, site -specific Background Screening Values (BSVs) were
established for the site. This appendix documents the methodology used for the BSV calculations.
The ProUCL software version 5.1 (ProUCL) published by the United States Environmental
Protection Agency (EPA) was used to calculate statistics on the background metals sets, as
described further below. A table summarizing the calculation results and the ProUCL output
sheets are included in this appendix.
Qnil RC17e
During historical assessment activities, a total of 16 background soil samples were collected at
locations upgradient of the site and outside the area of fill material. Prior reports documented
calculation of 95% upper confidence limits (UCLs) for soil, which represent the upper boundary
of the mean of background concentrations. UCLs are appropriate for background metals
evaluations when comparing mean concentrations in the source area to mean background
concentrations. However, the risk assessment for the subject site is based on maximum source area
concentrations rather mean concentrations. For maximum point source concentration
comparisons, EPA guidance indicates that use of the 95% Upper Tolerance Limit (UTL) with 95%
coverage is more appropriate (EPA, 2015). This UTL represents the value below which 95% of
the population values are expected to fall with 95% confidence.
The calculated BSVs for soil represent the 95% UTLs for the background soil data set, which were
calculated using the following steps:
• A 95% UTL was calculated for multiple potential data distributions, including normal,
gamma, lognormal, and nonparametric.
• A Goodness of Fit (GoF) test was run on each dataset to determine which distribution fit
the background dataset.
• A 95% UTL was selected based on which distribution best fit the dataset:
o For datasets that potentially fit both the normal and gamma distributions, the 95%
UTL for the distribution with the highest coefficient of correlation (R) was used.

o For datasets that only fit either the normal or gamma distribution, the 95% UTL for
the distribution which the dataset fit (normal or gamma) was used.
o For datasets that did not fit normal or gamma distributions, but fit the lognormal
distribution, the lognormal 95% UTL was used.
o For datasets which did not fit any distribution, the nonparametric 95% UTL was
used.
Non -detects were incorporated into the calculations using the Kaplan -Meier (KM) method. For
thallium, Pro-UCL was unable to calculate either a 95% UTL or a mean concentration because
thallium was detected in only one of the background samples. As referenced below, EPA guidance
also references use of two times the mean background concentration as an appropriate method of
calculating BSVs. For thallium, a value of two times the mean concentration was calculated using
half of the reporting limit as the concentration for non -detect values. Note that this value is less
than the maximum concentration detected in site background samples and considered
conservative.
Sediment and Surface Water Background ScreeningValues
alues
During historical assessment activities, a total of four background sediment samples and
five background surface water samples were collected at locations upstream of the site and outside
the area of fill material. The number of samples is insufficient to calculate a 95% UTL. EPA
guidance alternately recommends use of twice the site -specific background mean concentrations
as BSVs (EPA, 2018a and 2018b). These values were calculated for the subject site. In some
cases, two times the mean concentrations derived values that were higher than the maximum
concentrations detected in the background samples. In order to provide for additional
conservatism, the BSVs used for sediment and surface water represent the lower of the maximum
background concentration or twice the site -specific background mean concentration.
For the purposes of calculating the site -specific background mean concentrations, duplicate sample
results were averaged with their parent sample results prior to calculating the background mean
concentrations. Additionally, for datasets with non -detect values, the ProUCL software was
utilized to calculate the background mean concentrations following the KM method.

Table B-1 (page 1 of 1)
Summary of Background Screening Values (BSVs) for Soil
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
E
E
E
Sample ID
o
E
E
E
E
E
o
E
_
E
E
E
E
E
E
_
m
_
v
j
y
_
_
E
3
E
_
_
@
o
-
-
E
E
E
E
-
-
-
Site Background Data
Ml (0-1)
NA
<0.30
2.1
76
0.99
NA
<0.30
NA
0.43 J
17.57
18
27
49
NA
4.0
NA
710
<0.023
NA
5.0
NA
<0.59
NA
NA
25
<0.59
190
47
Ml (6-7)
NA
<0.27
1.4
61
0.60
NA
<0.27
NA
0.81
38.19
39
19
18
NA
0.55
NA
940
<0.020
NA
20
NA
<0.53
NA
NA
29
2.3
67
75
BG-1 (0-1)
NA
<0.28
1.9
36
0.39
NA
<0.28
NA
0.87
17.13
18
6.3
16
NA
25
NA
310
0.033
NA
5.4
NA
1.6
NA
NA
15
<0.57
34
43
BG-1 (2-3)
NA
<0.29
2.3
45
0.48
NA
<0.29
NA
<0.12
19
19
7.3
18
NA
43
NA
440
0.280
NA
6.2
NA
1.6
NA
NA
15
<0.57
35
49
BG-2(0-1)
NA
<0.28
1.9
45
0.50
NA
<0.28
NA
0.84
16.16
17
7.4
18
NA
32
NA
410
0.045
NA
4.9
NA
1.1
NA
NA
14
<0.56
35
44
BG-2 (2-3)
NA
<0.27
1.9
52
0.53
NA
<0.27
NA
0.70
23.3
24
7.5
20
NA
26
NA
450
0.038
NA
7.9
NA
1.7
NA
NA
19
<0.55
37
45
BG3 (0-1)
NA
<0.30
1.7
44
0.43
NA
<0.30
NA
0.21 J
23.3
16
7.5
15
NA
25
NA
410
0.024
NA
5.1
NA
1.4
NA
NA
46
<0.60
37
40
BG-3 (2-3)
NA
<0.27
2.2
56
0.54
NA
<0.27
NA
0.88
21.12
22
7.5
18
NA
29
NA
410
0.040
NA
5.2
NA
1.2
NA
NA
19
<0.53
40
46
BG-4 (0-1)
NA
<0.29
1.7
50
0.50
NA
<0.29
NA
<0.13
19
19
9.5
16
NA
22
NA
450 BH
0.026
NA
6.0
NA
<0.59
NA
NA
16 A
<0.59
53
50
BG-4 (2-3)
NA
<0.33
2.0
53
0.52
NA
0.38
NA
0.50 J
22.5
23
11
23
NA
21
NA
460 BH
0.054
NA
8.5
NA
<0.65
NA
NA
19
<0.65
51
230
BG-6 (0-1)
NA
NA
2.0501
64.4
0.625
NA
0.177 J
NA
5.34
39.4
44.7
14.4
26.4
NA
NA
NA
448 J6
0.022
NA
12.8
NA
0.562 J
NA
NA
17
NA
NA
NA
BG-6 (2-3)
NA
NA
2.29
66.3
0.507 J
NA
0.139 J
NA
<1.19
22.9
22.9
14.7
32.3
NA
NA
NA
467
0.032
NA
7.78
NA
0.828
NA
NA
16.8
NA
NA
NA
BG-7 (0-1)
NA
NA
1.97
52.7
0.410 J
NA
0.136 J
NA
<1.16
70.2
70.2
18.9
36.4
NA
NA
NA
813
0.025
NA
12.8
NA
0.543 J
NA
NA
22.6
NA
NA
NA
BG-7 (2-3)
NA
NA
3.08
77.9
0.430 J
NA
0.108 J
NA
<1.16
27
27
16.3
32.5
NA
NA
NA
548
0.023
NA
6.2
NA
0.502 J
NA
NA
24.3
NA
NA
NA
BG-8 (0-1)
NA
NA
1.8
52.4
0.370 J
NA
0.09511
NA
<1.14
24.5
24.5
21.8
62.8
NA
NA
NA
759
0.0072
NA
9.04
NA
0.485 J
NA
NA
24.4
NA
NA
NA
BG-8 2-3
NA
NA
1.66
47.6
0.293 J
NA
0.0918 J
NA
<1.14
21.7
21.7
23.5
60.2
NA
NA
NA
732
<0.0067
NA
7.86
NA
0.306 J
NA
NA
25.1
NA
NA
NA
Backaround Statistics
North Carolina Background Ranger)
7000 - >100,000
<1.0-8.8
1-18
50-1,000
ND-1.0
ND-100
1.0-10
101
NS
INS
7-300
ND-50
2.0-20
100->100,000`
ND-50
50-50,001
<2.0-7000'
0.03-0.52
<3-15*
ND
50-37,000'
<0.1-0.8
ND-5.0
<500-50,000`
ND-300
NS
15-300
11-59
Site Specific Background Range
NA
ND
1.4-3.08
36-77.9
0.293-0.99
NA
<0.27-0.38
NA
<0.12-5.34
16.16-70.2
16-70.2
6.3-27
15-62.8
NA
0.55-43
NA
310-940
<0.0067-0.28
NA
4.9-20
NA
<0.53-1.7
NA
NA
14-46
<0.53-2.3
34-190
40-230
2x Mean Background
NA
ND
3.994
109.92
1.014
NA
0.28
NA
1.696
52.86
53.26
27.46
57.7
NA
45.52
NA
1094.6
0.0842
NA
16.336
NA
1.708
NA
NA
43.4
INC
115.8
133.8
Selected 95% UTL with 95% Coverage
NA
NC
3.015
87.86
0.929
NA
0.313
NA
5.725
70.2
70.2
36.31
77.3
NA
59.11
NA
1149
0.256
NA
19.49
NA
2.503
NA
NA
43.19
INC
227
230
Recommended Site-S ecific BSVI"31
NA
ND
3.015
87.86
0.929
NA
0.313
NA
5.725
70.2
70.2
36.31
77.3
NA
59.11
NA
1149
0.256
NA
19.49
NA
2.503
NA
NA
43.19
0.981
227
230
1) North Carolina Soil Background Range taken from Elements in North American Soils, 2nd Edition by James Dragun and Khaled Chekiri
2) Recommended Site -Specific Background Screening Value (BSV) based on 95% UTL with 95% coverage for all constituents except thallium.
3) Thallium did not have enough detects to run Phil statistics. Site -specific BSV was calculated as 2x the mean using 1/2 of the reporting limits as the values for non -detects.
NA = Not Analyzed; ND = Not Detected; --= Not Calculated; UTL = Upper Tolerance Limit
J - Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration
01 = Analyte failed the method required serial dilution test and/or subsequent post -spike criteria. These failures indicate matrix interference.
J6 = The sample matrix interfered with the ability to make any accurate determination; spike value is low.
BH = Method blank greater than one-half laboratory reporting limit, but sample concentration greater than 1 Ox the method blank.
A = Continuing Calibration Verification standard recovery (82%) is less than the lower control limit (90 % ). Result has possible low bias.
Hart & Hickman, PC

Table B-2 (page 1 of 1)
Summary of Background Screening Values (BSVs) for Sediment
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
E
E
E
O
r
E
E
Sediment Sampling Point ID
Sample Date
2
N
E
E
U
o
c
L
E
E
E
7
E
U
a�i
�
7
7
E
CO
CO
C
m
r
U
_
CO
a
o
CM
Y
7
o
C
m
m
CO
-0
N
-0
O
(6
U
X
N
s
6
O
d
O
U
Q
O
U
M
CO
E
N
E
U
N
O
rn
0
L
C
>
U
C
SED-1
10/27/2016
1.2
12
0.24 J
22.76
23
3.9
4.2
4.0
180
3.8
6.9
19
19
(Upstream)
4/5/2019
1.9501
38.4 J6
0.249 J
0.428 J
65.0
65.4 J3, J6
7.63
8.42
449 J6
0.0078
7.1
0.409 J
8.4
10/27/2016
2.1
20
0.48
36
36
7.8
8.0
7.1
330
7.2
11
37
34
SED-2
10/27/2016(')
2.5
17
0.45
49
49
6.5
9.1
6.7
290
6.0
12
35
31
(Upstream)
4/5/2019
2.74
29.6
0.305 J
0.796 J
56.3
57.1
20.9
13.8
811
0.0053 J
9.16
0.306 J
16.9
4/5/2019(')
2.02
17.4
0.222 J
0.546 J
69.5
70
7.29
6.79
347
0.0051
9.92
0.237 J
8.8
Background Statistics
Site -Specific Background Range
ND
1.2-2.74
12-38.4
<0.32-0.48
<0.32-<0.636
0.24 J-0.796 J
22.76-69.5
23-70
3.9-20.9
4.2-13.8
4.0-7.1
180-811
<0.026 - 0.0078
3.8-9.92
0.237 J-<0.65
6.9-16.9
<0.63-<0.65
19-37
19-34
Site -Specific Mean (2)
ND
1.958
23.1
0.308
ND
0.395
48.28
48.61
8.194
7.866
5.45
379.5
0.0065
6.76
0.34
9.913
ND
27.5
25.75
2X Site -Specific Mean
ND
3.916
46.2
0.616
1 ND
0.79
96.56
97.22
1 16.388
15.732
10.9
759
0.013
13.52
1 0.68
19.826
ND
55
51.5
Recommended Site -Specific BSV3)
ND
1 2.74
38.4
0.48
1 ND
1 0.79
1 69.5
70
1 16.388
13.8
7.1
759
0.0078
1 9.92
1 0.409
1 16.9
ND
1 37
1 34
Notes:
1) Duplicate sample data, average of parent sample and duplicate used in calculations.
2) Site -specific mean for datasets with non -detects calculated using Kaplan -Meier Method via ProUCL version 5.1.
3) Recommended Site -Specific Background Screening Value (BSV) indicates 2x mean background concentration or maximum detected concentration, whichever is lower.
NA = Not Analyzed; ND = Not Detected
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
01 = Analyte failed the method required serial dilution test and/or subsequent post -spike criteria. These failures indicate matrix interference.
J3 = The associated batch QC was outside the established quality control range for precision.
J6 = The sample matrix interfered with the ability to make any accurate determination; spike value is low.
Hart & Hickman, PC

Table B-3 (page 1 of 1)
Summary of Background Screening Values (BSVs) for Surface Water
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job No. TCH-009
E
E
o
L
E
�
Surface Water Background
Sample Date
t
E
E
d
Sample Location
E
>,
E
E
m
o
o
2
N
E
y
C
O
U
E
J
2
E
@
C
L
o•
N
N
ST
y
J
?
?
E
c
N
Z
a
x
m
a
a
c
a
m
s
o
o
-
m
a
m
m
s
p
O
O
�_
a�
E
E
E
C
n
°�
s
f0
S
BC-1 (Upstream)
2/5/2014
NA
24
NA
NA
NA
I
NA
NA
I
I NA
ND
NA
I
NA
SWA
11/3/2016
NA
U
27
<2.0
-
b.<
<5.0
<10
<
NA
<10
<
<10
<20
100
<10
(Upstream)
4/5/2019
NA
0.44
23.1
<0.10
<0.0
0.53
0.16
1.2
I
NA
22.2
<I
0.29 J
0.096 J
85.3
NA
54,000
11/3/2016
NA
.,..,
<10
27
<2.0
<1
<5.0
<5.0
<10
<
NA
11
<
-i0
,.,,
-20
100
<10
NA
SW-2(Upstream)
4/5/2019
NA
NA
0.42
23.2
<0.10
0.45 J
0.16
1.1
I.
NA
21.2
<I
0.33 J
NA
0.11 J
85.5
NA
53,600
Background Statistics
Site Specific Background Range
NA
ND
<10 - 0.44
23.1 -27
ND
ND
NA
ND
ND
<5.0 - 0.53
<5.0-0.16
<10 - 1.2
ND
ND
NA
<10 - 22.2
ND
<10 - 0.33 J
NA
<20 - 0.11 J
85.3 - 100
ND
NA
ND
ND
ND
53,600 - 54,000
Site Specific Mean(')
NA
ND
0.43
24.86
ND
ND
NA
ND
ND
0.49
1.33(3)
1.15
ND
ND
NA
16.1
ND
0.31
NA
0.103
92.7
ND
NA
ND
ND
ND
53,800
2X Site Spmcifec Mea
NA
NNDD
086
4972
NNDD
NNDD
NA
0.
.
NDD
NA
ND
.
A
02
80504
N
NA
NDD
N
N
07,,000
Recomnded Site -Specific BSV�1
0.4
7
A
ND
2
NNN
03
A
101
4000
Notes:
1) Site specific mean for datasets with non -detects calculated using Kaplan -Meier Method via PrOUCL version 5.1
2) Recommended Site -Specific Background Screening Value (BSV) indicates 2x mean background concentration or maximum detected concentration, whichever is lower.
3) The Kaplan -Meier mean could not be calculated for Cobalt, as there was only one unique detection. Therefore, the site -specific mean was calculated using 1 /2 of the reporting limits as the values for non -detects.
NA = Not Analyzed; ND = Not Detected; NC = Not Calculated
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration
Hart & Hickman, PC

Background Statistics for Data Sets with Non -Detects
User Selected Options
Date/Time of Computation
ProUCL 5.18/17/2021 4:10:55 PM
From File
ProUCL Background Inputs.xls
Full Precision
OFF
Confidence Coefficient
95%
Coverage
95%
Different or Future K Observations
1
Number of Bootstrap Operations
2000
antimony
General Statistics
Total Number of Observations
10
Number of Missing Observations
6
Number of Distinct Observations
5
Number of Detects
0
Number of Non -Detects
10
Number of Distinct Detects
0
Number of Distinct Non -Detects
5
Minimum Detect
N/A
Minimum Non -Detect
0.27
Maximum Detect
N/A
Maximum Non -Detect
0.33
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: All observations are Non -Detects (NDs), therefore all statistics and estimates should also be NDs!
Specifically, sample mean, UCLs, UPLs, and other statistics are also NDs lying below the largest detection limit!
The Project Team may decide to use alternative site specific values to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable antimony was not processed!
arsenic
General Statistics
Total Number of Observations
16
Number of Distinct Observations
13
Minimum
1.4
First Quartile
1.775
Second Largest
2.3
Median
1.935
Maximum
3.08
Third Quartile
2.125
Mean
1.997
SD
0.376
Coefficient of Variation
0.188
Skewness
1.463
Mean of logged Data
0.676
SD of logged Data
0.176
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.887
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.147
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level

Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
2.946
90% Percentile (z)
2.479
95% UPL (t)
2.676
95% Percentile (z)
2.615
95% USL
2.915
99% Percentile (z)
2.871
Gamma GOF Test
A-D Test Statistic
0.399
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.736
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.124
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.215
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
33.27
k star (bias corrected MLE)
27.08
Theta hat (MLE)
0.06
Theta star (bias corrected MLE)
0.0737
nu hat (MLE)
1065
nu star (bias corrected)
866.4
MLE Mean (bias corrected)
1.997
MLE Sd (bias corrected)
0.384
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
2.69
90% Percentile
2.502
95% Hawkins Wixley (HW) Approx. Gamma UPL
2.693
95% Percentile
2.667
95% WH Approx. Gamma UTL with 95% Coverage
3.015
99% Percentile
2.996
95% HW Approx. Gamma UTL with 95% Coverage
3.027
95% WH USL
2.977
95% HW USL 2. 888
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.948
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.125
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
3.069
90% Percentile (z)
2.465
95% UPL (t)
2.705
95% Percentile (z)
2.628
95% USL
3.026
99% Percentile (z)
2.964
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
3.08
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
3.08
95% BCA Bootstrap UTL with 95% Coverage
3.08
95% UPL
3.08
90% Percentile
2.295
90% Chebyshev UPL
3.159
95% Percentile
2.495
95% Chebyshev UPL
3.686
99% Percentile
2.963
95% USL
3.08

Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
barium
General Statistics
Total Number of Observations
16
Number of Distinct Observations
15
Minimum
36
First Quartile
46.95
Second Largest
76
Median
52.55
Maximum
77.9
Third Quartile
61.85
Mean
54.96
SD
11.56
Coefficient of Variation
0.21
Skewness
0.653
Mean of logged Data
3.986
SD of logged Data
0.206
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.942
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.192
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
84.14
90% Percentile (z)
69.77
95% UPL (t)
75.85
95% Percentile (z)
73.97
95% USL
83.21
99% Percentile (z)
81.85
Gamma GOF Test
A-D Test Statistic
0.321
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.736
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.17
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.215
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
25.01
k star (bias corrected MLE)
20.36
Theta hat (MLE)
2.197
Theta star (bias corrected MLE)
2.699
nu hat (MLE)
800.4
nu star (bias corrected)
651.7
MLE Mean (bias corrected)
54.96
MLE Sd (bias corrected)
12.18
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
77.19
90% Percentile
71.03
95% Hawkins Wixley (HW) Approx. Gamma UPL
77.42
95% Percentile
76.4
95% WH Approx. Gamma UTL with 95% Coverage
87.86
99% Percentile
87.18

95% HW Approx. Gamma UTL with 95% Coverage
88.48
95% WH USL
86.61
95% HW USL 87.18
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.968
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.156
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
90.65
90% Percentile (z)
70.16
95% UPL (t)
78.19
95% Percentile (z)
75.62
95% USL
89.16
99% Percentile (z)
87.03
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
77.9
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
77.9
95% BCA Bootstrap UTL with 95% Coverage
77.9
95% UPL
77.9
90% Percentile
71.15
90% Chebyshev UPL
90.71
95% Percentile
76.48
95% Chebyshev UPL
106.9
99% Percentile
77.62
95% USL
77.9
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
beryllium
General Statistics
Total Number of Observations
16
Number of Distinct Observations
14
Minimum
0.293
First Quartile
0.425
Second Largest
0.625
Median
0.5
Maximum
0.99
Third Quartile
0.533
Mean
0.507
SD
0.154
Coefficient of Variation
0.305
Skewness
2.049
Mean of logged Data
-0.715
SD of logged Data
0.268
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.813
Shapiro Wilk GOF Test

5% Shapiro Wilk Critical Value
0.887
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.228
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data Not Normal at 5% Significance Level
Data Not Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
0.897
90% Percentile (z)
0.705
95% UPL (t)
0.786
95% Percentile (z)
0.761
95% USL
0.885
99% Percentile (z)
0.867
Gamma GOF Test
A-D Test Statistic
0.558
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.738
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.185
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.215
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
14.04
k star (bias corrected MLE)
11.45
Theta hat (MLE)
0.0361
Theta star (bias corrected MLE)
0.0443
nu hat (MLE)
449.4
nu star (bias corrected)
366.5
MLE Mean (bias corrected)
0.507
MLE Sd (bias corrected)
0.15
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
0.787
90% Percentile
0.706
95% Hawkins Wixley (HW) Approx. Gamma UPL
0.788
95% Percentile
0.776
95% WH Approx. Gamma UTL with 95% Coverage
0.929
99% Percentile
0.919
95% HW Approx. Gamma UTL with 95% Coverage
0.936
95% WH USL
0.912
95% HW LISLF 0.918
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.933
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.169
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
0.962
90% Percentile (z)
0.69
95% UPL (t)
0.794
95% Percentile (z)
0.76
95% USL
0.942
99% Percentile (z)
0.913
Nonparametric Distribution Free Background Statistics
Data appear Gamma Distributed at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
0.99
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
0.99
95% BCA Bootstrap UTL with 95% Coverage
0.99

95% UPL
0.99
90% Percentile
0.613
90% Chebyshev UPL
0.985
95% Percentile
0.716
95% Chebyshev UPL
1.201
99% Percentile
0.935
95% USL
0.99
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
cadmium
General Statistics
Total Number of Observations
16
Number of Missing Observations
0
Number of Distinct Observations
11
Number of Detects
7
Number of Non -Detects
9
Number of Distinct Detects
7
Number of Distinct Non -Detects
4
Minimum Detect
0.0918
Minimum Non -Detect
0.27
Maximum Detect
0.38
Maximum Non -Detect
0.3
Variance Detected
0.0102
Percent Non -Detects
56.25%
Mean Detected
0.161
SD Detected
0.101
Mean of Detected Logged Data
-1.948
SD of Detected Logged Data
0.491
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test on Detects Only
Shapiro Wilk Test Statistic
0.712
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.803
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.3
Lilliefors GOF Test
5% Lilliefors Critical Value
0.304
Detected Data appear Normal at 5% Significance Level
Detected Data appear Approximate Normal at 5% Significance Level
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.14
KM SD
0.0682
95% UTL95% Coverage
0.313
95% KM UPL (t)
0.264
90% KM Percentile (z)
0.228
95% KM Percentile (z)
0.253
99% KM Percentile (z)
0.299
95% KM USL
0.307
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
0.15
SD
0.0648
95% UTL95% Coverage
0.314
95% UPL (t)
0.267
90% Percentile (z)
0.233
95% Percentile (z)
0.257
99% Percentile (z)
0.301
95% USL
0.309
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
A-D Test Statistic
0.646
Anderson -Darling GOF Test
5% A-D Critical Value
0.71
Detected data appear Gamma Distributed at 5% Significance Level

K-S Test Statistic
0.267
1 Kolmogorov-Smirnov GOF
5% K-S Critical Value
0.313
1 Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics on Detected Data Only
k hat (MLE)
4.282
k star (bias corrected MLE)
2.542
Theta hat (MLE)
0.0376
Theta star (bias corrected MLE)
0.0633
nu hat (MLE)
59.94
nu star (bias corrected)
35.59
MLE Mean (bias corrected)
0.161
MLE Sd (bias corrected)
0.101
95% Percentile of Chisquare (2kstar) 11.2
Gamma ROS Statistics using Imputed Non -Detects
GROS may not be used when data set has > 50% NDs with many tied observations at multiple DLs
GROS may not be used when kstar of detects is small such as <1.0, especially when the sample size is small (e.g., <15-20)
For such situations, GROS method may yield incorrect values of UCLs and BTVs
This is especially true when the sample size is small.
For gamma distributed detected data, BTVs and UCLs may be computed using gamma distribution on KM estimates
Minimum
0.0789
Mean
0.143
Maximum
0.38
Median
0.131
SD
0.0718
CV
0.503
k hat (MLE)
6.178
k star (bias corrected MLE)
5.062
Theta hat (MLE)
0.0231
Theta star (bias corrected MLE)
0.0282
nu hat (MLE)
197.7
nu star (bias corrected)
162
MLE Mean (bias corrected)
0.143
MLE Sd (bias corrected)
0.0634
95% Percentile of Chisquare (2kstar)
18.48
90% Percentile
0.228
95% Percentile
0.26
99% Percentile
0.33
The following statistics are computed using Gamma ROS Statistics on Imputed Data
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.335
0.339
95% Approx. Gamma UPL
0.266
0.266
95% Gamma USL
0.327
0.33
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.14
SD (KM)
0.0682
Variance (KM)
0.00465
SE of Mean (KM)
0.0207
k hat (KM)
4.238
k star (KM)
3.485
nu hat (KM)
135.6
nu star (KM)
111.5
theta hat (KM)
0.0331
theta star (KM)
0.0403
80% gamma percentile (KM)
0.197
90% gamma percentile (KM)
0.241
95% gamma percentile (KM)
0.283
99% gamma percentile (KM)
0.371
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.313
0.314
95% Approx. Gamma UPL
0.252
0.25
95% KM Gamma Percentile
0.239
0.237
95% Gamma USL
0.306
0.307
Lognormal GOF Test on Detected Observations Only
Shapiro Wilk Test Statistic
0.851
1 Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.803
1 Detected Data appear Lognormal at 5% Significance Level

Lilliefors Test Statistic
0.235
1 Lilliefors GOF Test
5% Lilliefors Critical Value
0.304
1 Detected Data appear Lognormal at 5% Significance Level
Detected Data appear Lognormal at 5% Significance Level
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.143
Mean in Log Scale
-2.02
SD in Original Scale
0.0693
SD in Log Scale
0.358
95% UTL95% Coverage
0.327
95% BCA UTL95% Coverage
0.38
95% Bootstrap (%) UTL95% Coverage
0.38
95% UPL (t)
0.253
90% Percentile (z)
0.21
95% Percentile (z)
0.239
99% Percentile (z)
0.305
95% USL
0.318
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-2.04
95% KM UTL (Lognormal)95% Coverage
0.32
KM SD of Logged Data
0.357
95% KM UPL (Lognormal)
0.248
95% KM Percentile Lognormal (z)
0.234
95% KM USL (Lognormal)
0.311
Background DU2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
0.15
Mean in Log Scale
-1.952
SD in Original Scale
0.0648
SD in Log Scale
0.312
95% UTL95% Coverage
0.312
95% UPL (t)
0.25
90% Percentile (z)
0.212
95% Percentile (z)
0.237
99% Percentile (z)
0.293
95% USL
0.304
DU2 is not a Recommended Method. DU2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data appear to follow a Discernible Distribution at 5% Significance Level
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
16
95% UTL with95% Coverage
0.38
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% UPL
0.38
95% USL
0.38
95% KM Chebyshev UPL
0.447
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
hexavalent chromium
General Statistics
Total Number of Observations
16
Number of Missing Observations
0
Number of Distinct Observations
14
Number of Detects
9
Number of Non -Detects
7
Number of Distinct Detects
9
Number of Distinct Non -Detects
5
Minimum Detect
0.21
Minimum Non -Detect
0.12
Maximum Detect
5.34
Maximum Non -Detect
1.19
Variance Detected
2.493
Percent Non -Detects
43.75%

Mean Detected
1.176
SD Detected
1.579
Mean of Detected Logged Data
-0.27
SD of Detected Logged Data
0.867
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test on Detects Only
Shapiro Wilk Test Statistic
0.531
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.829
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.463
Lilliefors GOF Test
5% Lilliefors Critical Value
0.274
Data Not Normal at 5% Significance Level
Data Not Normal at 5% Significance Level
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.848
KM SD
1.195
95% UTL95% Coverage
3.864
95% KM UPL (t)
3.007
90% KM Percentile (z)
2.379
95% KM Percentile (z)
2.814
99% KM Percentile (z)
3.628
95% KM USL
3.768
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
0.85
SD
1.225
95% UTL95% Coverage
3.941
95% UPL (t)
3.063
90% Percentile (z)
2.42
95% Percentile (z)
2.865
99% Percentile (z)
3.699
95% USL
3.843
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
A-D Test Statistic
1.129
Anderson -Darling GOF Test
5% A-D Critical Value
0.738
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.394
Kolmogorov-Smirnov GOF
5% K-S Critical Value
0.285
Data Not Gamma Distributed at 5% Significance Level
Data Not Gamma Distributed at 5% Significance Level
Gamma Statistics on Detected Data Only
k hat (MLE)
1.299
k star (bias corrected MLE)
0.94
Theta hat (MLE)
0.905
Theta star (bias corrected MLE)
1.25
nu hat (MLE)
23.38
nu star (bias corrected)
16.92
MLE Mean (bias corrected)
1.176
MLE Sd (bias corrected)
1.212
95% Percentile of Chisquare (2kstar) 5.757
Gamma ROS Statistics using Imputed Non -Detects
GROS may not be used when data set has > 50% NDs with many tied observations at multiple DLs
GROS may not be used when kstar of detects is small such as <1.0, especially when the sample size is small (e.g., <15-20)
For such situations, GROS method may yield incorrect values of UCLs and BTVs
This is especially true when the sample size is small.
For gamma distributed detected data, BTVs and UCLs may be computed using gamma distribution on KM estimates
Minimum
0.01
Mean
0.791
Maximum
5.34
Median
0.6
SD
1.263
CV
1.598
k hat (MLE)
0.541
k star (bias corrected MLE)
0.482

Theta hat (MLE)
1.46
Theta star (bias corrected MLE)
1.642
nu hat (MLE)
17.33
nu star (bias corrected)
15.41
MLE Mean (bias corrected)
0.791
MLE Sd (bias corrected)
1.139
95% Percentile of Chisquare (2kstar)
3.75
90% Percentile
2.155
95% Percentile
1 3.078
99% Percentile
5.354
The following statistics are computed using Gamma ROS Statistics on Imputed Data
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
5.5
6.852
95% Approx. Gamma UPL
3.222
3.638
95% Gamma USL
5.202
6.412
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.848
SD (KM)
1.195
Variance (KM)
1.429
SE of Mean (KM)
0.322
k hat (KM)
0.503
k star (KM)
0.45
nu hat (KM)
16.09
nu star (KM)
14.4
theta hat (KM)
1.686
theta star (KM)
1.883
80% gamma percentile (KM)
1.383
90% gamma percentile (KM)
2.342
95% gamma percentile (KM)
3.379
99% gamma percentile (KM)
5.956
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
3.926
4.122
95% Approx. Gamma UPL
2.562
2.577
95% KM Gamma Percentile
2.305
2.299
95% Gamma USL
3.753
3.92
Lognormal GOF Test on Detected Observations Only
Shapiro Wilk Test Statistic
0.852
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.829
Detected Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.324
Lilliefors GOF Test
5% Lilliefors Critical Value
0.274
Data Not Lognormal at 5% Significance Level
Detected Data appear Approximate Lognormal at 5% Significance Level
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.836
Mean in Log Scale
-0.641
SD in Original Scale
1.23
SD in Log Scale
0.893
95% UTL95% Coverage
5.021
95% BCA UTL95% Coverage
5.34
95% Bootstrap (%) UTL95% Coverage
5.34
95% UPL (t)
2.647
90% Percentile (z)
1.655
95% Percentile (z)
2.29
99% Percentile (z)
4.208
95% USL
4.672
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-0.678
95% KM UTL (Lognormal)95% Coverage
5.725
KM SD of Logged Data
0.96
95% KM UPL (Lognormal)
2.877
95% KM Percentile Lognormal (z)
2.462
95% KM USL (Lognormal)
5.298
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
0.85
Mean in Log Scale
-0.669
SD in Original Scale
1.225
SD in Log Scale
1.045
95% UTL95% Coverage
7.159
95% UPL (t)
3.384

90% Percentile (z)
1.954
95% Percentile (z)
2.857
99% Percentile (z)
5.823
1 95% USL
6.58
DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data appear to follow a Discernible Distribution at 5% Significance Level
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
16
95% UTL with95% Coverage
5.34
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% UPL
5.34
95% USL
5.34
95% KM Chebyshev UPL
6.218
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
trivalent chromium
General Statistics
Total Number of Observations
16
Number of Distinct Observations
14
Minimum
16.16
First Quartile
19
Second Largest
39.36
Median
22.7
Maximum
70.2
Third Quartile
25.13
Mean
26.43
SD
13.43
Coefficient of Variation
0.508
Skewness
2.637
Mean of logged Data
3.194
SD of logged Data
0.377
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.668
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.307
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data Not Normal at 5% Significance Level
Data Not Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
60.32
90% Percentile (z)
43.64
95% UPL (t)
50.7
95% Percentile (z)
48.52
95% USL
59.24
99% Percentile (z)
57.67
Gamma GOF Test
A-D Test Statistic
1.306
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.741
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.272
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.216
Data Not Gamma Distributed at 5% Significance Level

Data Not Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
6.387
k star (bias corrected MLE)
5.231
Theta hat (MLE)
4.139
Theta star (bias corrected MLE)
5.053
nu hat (MLE)
204.4
nu star (bias corrected)
167.4
MLE Mean (bias corrected)
26.43
MLE Sd (bias corrected)
11.56
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
48.8
90% Percentile
41.9
95% Hawkins Wixley (HW) Approx. Gamma UPL
48.63
95% Percentile
47.86
95% WH Approx. Gamma UTL with 95% Coverage
61.37
99% Percentile
60.42
95% HW Approx. Gamma UTL with 95% Coverage
61.72
95% WH USL
59.86
95% HW USL 60.12
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.831
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.245
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data Not Lognormal at 5% Significance Level
Data Not Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
63.2
90% Percentile (z)
39.55
95% UPL (t)
48.22
95% Percentile (z)
45.36
95% USL
61.3
99% Percentile (z)
58.66
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
70.2
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
70.2
95% BCA Bootstrap UTL with 95% Coverage
70.2
95% UPL
70.2
90% Percentile
38.78
90% Chebyshev UPL
67.95
95% Percentile
47.07
95% Chebyshev UPL
86.76
99% Percentile
65.57
95% USL
70.2
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
total chromium
General Statistics
Total Number of Observations 16
Number of Distinct Observations
14

Minimum
16
First Quartile
18.75
Second Largest
44.7
Median
22.45
Maximum
70.2
Third Quartile
25.13
Mean
26.63
SD
13.98
Coefficient of Variation
0.525
Skewness
2.394
Mean of logged Data
3.194
SD of logged Data
0.397
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.689
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.31
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data Not Normal at 5% Significance Level
Data Not Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
61.92
90% Percentile (z)
44.55
95% UPL (t)
51.89
95% Percentile (z)
49.63
95% USL
60.79
99% Percentile (z)
59.16
Gamma GOF Test
A-D Test Statistic
1.323
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.741
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.273
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.216
Data Not Gamma Distributed at 5% Significance Level
Data Not Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
5.828
k star (bias corrected MLE)
4.777
Theta hat (MLE)
4.568
Theta star (bias corrected MLE)
5.573
nu hat (MLE)
186.5
nu star (bias corrected)
152.9
MLE Mean (bias corrected)
26.63
MLE Sd (bias corrected)
12.18
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
50.36
90% Percentile
42.94
95% Hawkins Wixley (HW) Approx. Gamma UPL
50.22
95% Percentile
49.3
95% WH Approx. Gamma UTL with 95% Coverage
63.88
99% Percentile
62.77
95% HW Approx. Gamma UTL with 95% Coverage
64.37
95% WH USL
62.25
95% HW USL 62.64
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.833
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.245
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data Not Lognormal at 5% Significance Level
Data Not Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution

95% UTL with 95% Coverage
66.4
90% Percentile (z)
40.55
95% UPL (t)
49.95
95% Percentile (z)
46.84
95% USL
64.31
99% Percentile (z)
61.39
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
70.2
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
70.2
95% BCA Bootstrap UTL with 95% Coverage
70.2
95% UPL
70.2
90% Percentile
41.85
90% Chebyshev UPL
69.87
95% Percentile
51.08
95% Chebyshev UPL
89.46
99% Percentile
66.38
95% USL
70.2
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
cobalt
General Statistics
Total Number of Observations
16
Number of Distinct Observations
14
Minimum
6.3
First Quartile
7.5
Second Largest
23.5
Median
12.7
Maximum
27
Third Quartile
18.93
Mean
13.73
SD
6.721
Coefficient of Variation
0.49
Skewness
0.591
Mean of logged Data
2.506
SD of logged Data
0.494
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.891
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.198
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
30.69
90% Percentile (z)
22.34
95% UPL (t)
25.87
95% Percentile (z)
24.78
95% USL
30.15
99% Percentile (z)
29.36
Gamma GOF Test

A-D Test Statistic
0.69
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.742
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.218
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.216
Data Not Gamma Distributed at 5% Significance Level
Detected data follow Appr. Gamma Distribution at 5% Significance Level
Gamma Statistics
k hat (MLE)
4.558
k star (bias corrected MLE)
3.745
Theta hat (MLE)
3.011
Theta star (bias corrected MLE)
3.665
nu hat (MLE)
145.8
nu star (bias corrected)
119.8
MLE Mean (bias corrected)
13.73
MLE Sd (bias corrected)
7.092
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
27.93
90% Percentile
23.23
95% Hawkins Wixley (HW) Approx. Gamma UPL
28.34
95% Percentile
27.08
95% WH Approx. Gamma UTL with 95% Coverage
36.31
99% Percentile
35.32
95% HW Approx. Gamma UTL with 95% Coverage
37.53
95% WH USL
35.29
95% HW USL 36.4
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.9
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.215
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data Not Lognormal at 5% Significance Level
Data appear Approximate Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
42.66
90% Percentile (z)
23.08
95% UPL (t)
29.93
95% Percentile (z)
27.62
95% USL
40.99
99% Percentile (z)
38.69
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
27
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
27
95% BCA Bootstrap UTL with 95% Coverage
27
95% UPL
27
90% Percentile
22.65
90% Chebyshev UPL
34.51
95% Percentile
24.38
95% Chebyshev UPL
43.92
99% Percentile
26.48
95% USL
27
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.

copper
General Statistics
Total Number of Observations
16
Number of Distinct Observations
12
Minimum
15
First Quartile
18
Second Largest
60.2
Median
21.5
Maximum
62.8
Third Quartile
33.48
Mean
28.85
SD
15.78
Coefficient of Variation
0.547
Skewness
1.274
Mean of logged Data
3.244
SD of logged Data
0.482
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.801
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.213
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data appear Normal at 5% Significance Level
Data appear Approximate Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
68.68
90% Percentile (z)
49.07
95% UPL (t)
57.36
95% Percentile (z)
54.81
95% USL
67.41
99% Percentile (z)
65.56
Gamma GOF Test
A-D Test Statistic
0.943
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.742
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.212
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.216
Detected data appear Gamma Distributed at 5% Significance Level
Detected data follow Appr. Gamma Distribution at 5% Significance Level
Gamma Statistics
k hat (MLE)
4.383
k star (bias corrected MLE)
3.603
Theta hat (MLE)
6.582
Theta star (bias corrected MLE)
8.007
nu hat (MLE)
140.3
nu star (bias corrected)
115.3
MLE Mean (bias corrected)
28.85
MLE Sd (bias corrected)
15.2
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
59.22
90% Percentile
49.23
95% Hawkins Wixley (HW) Approx. Gamma UPL
59.64
95% Percentile
57.52
95% WH Approx. Gamma UTL with 95% Coverage
77.3
99% Percentile
75.31
95% HW Approx. Gamma UTL with 95% Coverage
79.13
95% WH USL
75.1
95% HW USL 76.72
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.876
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.206
Lilliefors Lognormal GOF Test

5% Lilliefors Critical Value
0.213
1 Data appear Lognormal at 5% Significance Level
Data appear Approximate Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
86.59
90% Percentile (z)
47.55
95% UPL (t)
61.27
95% Percentile (z)
56.66
95% USL
83.28
99% Percentile (z)
78.72
Nonparametric Distribution Free Background Statistics
Data appear Approximate Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
62.8
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
62.8
95% BCA Bootstrap UTL with 95% Coverage
62.8
95% UPL
62.8
90% Percentile
54.6
90% Chebyshev UPL
77.65
95% Percentile
60.85
95% Chebyshev UPL
99.75
99% Percentile
62.41
95% USL
62.8
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
lead
General Statistics
Total Number of Observations
10
Number of Distinct Observations
9
Number of Missing Observations
6
Minimum
0.55
First Quartile
21.25
Second Largest
32
Median
25
Maximum
43
Third Quartile
28.25
Mean
22.76
SD
12.49
Coefficient of Variation
0.549
Skewness
-0.582
Mean of logged Data
2.721
SD of logged Data
1.328
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.911 d2max (for USL) 2.176
Normal GOF Test
Shapiro Wilk Test Statistic
0.912
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.842
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.244
Lilliefors GOF Test
5% Lilliefors Critical Value
0.262
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution

95% UTL with 95% Coverage
59.11
90% Percentile (z)
38.76
95% UPL (t)
46.76
95% Percentile (z)
43.29
95% USL
49.93
99% Percentile (z)
51.8
Gamma GOF Test
A-D Test Statistic
1.256
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.741
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.377
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.272
Data Not Gamma Distributed at 5% Significance Level
Data Not Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
1.383
k star (bias corrected MLE)
1.034
Theta hat (MLE)
16.46
Theta star (bias corrected MLE)
22
nu hat (MLE)
27.65
nu star (bias corrected)
20.69
MLE Mean (bias corrected)
22.76
MLE Sd (bias corrected)
22.37
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
74.91
90% Percentile
51.96
95% Hawkins Wixley (HW) Approx. Gamma UPL
86.38
95% Percentile
67.36
95% WH Approx. Gamma UTL with 95% Coverage
126.4
99% Percentile
103
95% HW Approx. Gamma UTL with 95% Coverage
160.3
95% WH USL
86.44
95% HW USL 102.2
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.676
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.842
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.396
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.262
Data Not Lognormal at 5% Significance Level
Data Not Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
726.1
90% Percentile (z)
83.39
95% UPL (t)
195.4
95% Percentile (z)
135.1
95% USL
273.6
99% Percentile (z)
334
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
10
95% UTL with 95% Coverage
43
Approx, f used to compute achieved CC
0.526
Approximate Actual Confidence Coefficient achieved by UTL
0.401
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
43
95% BCA Bootstrap UTL with 95% Coverage
43
95% UPL
43
90% Percentile
33.1
90% Chebyshev UPL
62.05
95% Percentile
38.05
95% Chebyshev UPL
79.84
99% Percentile
42.01
95% USL
43
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.

Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
manganese
General Statistics
Total Number of Observations
16
Number of Distinct Observations
13
Minimum
310
First Quartile
432.5
Second Largest
813
Median
455
Maximum
940
Third Quartile
715.5
Mean
547.3
SD
182.1
Coefficient of Variation
0.333
Skewness
0.921
Mean of logged Data
6.257
SD of logged Data
0.313
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.854
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.295
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data Not Normal at 5% Significance Level
Data Not Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
1007
90% Percentile (z)
780.7
95% UPL (t)
876.4
95% Percentile (z)
846.9
95% USL
992.3
99% Percentile (z)
971
Gamma GOF Test
A-D Test Statistic
1.03
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.739
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.281
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.215
Data Not Gamma Distributed at 5% Significance Level
Data Not Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
10.67
k star (bias corrected MLE)
8.708
Theta hat (MLE)
51.31
Theta star (bias corrected MLE)
62.85
nu hat (MLE)
341.3
nu star (bias corrected)
278.7
MLE Mean (bias corrected)
547.3
MLE Sd (bias corrected)
185.5
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
899.2
90% Percentile
794.4
95% Hawkins Wixley (HW) Approx. Gamma UPL
903.3
95% Percentile
883.7
95% WH Approx. Gamma UTL with 95% Coverage
1083
99% Percentile
1068
95% HW Approx. Gamma UTL with 95% Coverage
1097
95% WH USL
1061
95% HW USL 1074

Lognormal GOF Test
Shapiro Wilk Test Statistic
0.896
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.264
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data Not Lognormal at 5% Significance Level
Data appear Approximate Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
1149
90% Percentile (z)
779
95% UPL (t)
918
95% Percentile (z)
872.6
95% USL
1120
99% Percentile (z)
1080
Nonparametric Distribution Free Background Statistics
Data appear Approximate Lognormal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
940
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
940
95% BCA Bootstrap UTL with 95% Coverage
940
95% UPL
940
90% Percentile
786
90% Chebyshev UPL
1110
95% Percentile
844.8
95% Chebyshev UPL
1366
99% Percentile
921
95% USL
940
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
mercury
General Statistics
Total Number of Observations
16
Number of Missing Observations
0
Number of Distinct Observations
15
Number of Detects
13
Number of Non -Detects
3
Number of Distinct Detects
13
Number of Distinct Non -Detects
3
Minimum Detect
0.0072
Minimum Non -Detect
0.0067
Maximum Detect
0.28
Maximum Non -Detect
0.023
Variance Detected
0.00492
Percent Non -Detects
18.75%
Mean Detected
0.0499
SD Detected
0.0701
Mean of Detected Logged Data
-3.402
SD of Detected Logged Data
0.807
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test on Detects Only
Shapiro Wilk Test Statistic
0.471
Shapiro Wilk GOF Test

5% Shapiro Wilk Critical Value
0.866
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.4
Lilliefors GOF Test
5% Lilliefors Critical Value
0.234
Data Not Normal at 5% Significance Level
Data Not Normal at 5% Significance Level
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.0421
KM SD
0.0629
95% UTL95% Coverage
0.201
95% KM UPL (t)
0.156
90% KM Percentile (z)
0.123
95% KM Percentile (z)
0.146
99% KM Percentile (z)
0.188
95% KM USL
0.196
DL/2 Substitution Background Statistics Assuming Normal Distribution
Mean
0.0421
SD
0.065
95% UTL95% Coverage
0.206
95% UPL (t)
0.16
90% Percentile (z)
0.125
95% Percentile (z)
0.149
99% Percentile (z)
0.193
95% USL
0.201
DL/2 is not a recommended method. DL/2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
A-D Test Statistic
1.525
Anderson -Darling GOF Test
5% A-D Critical Value
0.752
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.279
Kolmogorov-Smirnov GOF
5% K-S Critical Value
0.241
Data Not Gamma Distributed at 5% Significance Level
Data Not Gamma Distributed at 5% Significance Level
Gamma Statistics on Detected Data Only
k hat (MLE)
1.377
k star (bias corrected MLE)
1.111
Theta hat (MLE)
0.0363
Theta star (bias corrected MLE)
0.045
nu hat (MLE)
35.81
nu star (bias corrected)
28.88
MLE Mean (bias corrected)
0.0499
MLE Sd (bias corrected)
0.0474
95% Percentile of Chisquare (2kstar) 6.414
Gamma ROS Statistics using Imputed Non -Detects
GROS may not be used when data set has > 50% NDs with many tied observations at multiple DLs
GROS may not be used when kstar of detects is small such as <1.0, especially when the sample size is small (e.g., <15-20)
For such situations, GROS method may yield incorrect values of UCLs and BTVs
This is especially true when the sample size is small.
For gamma distributed detected data, BTVs and UCLs may be computed using gamma distribution on KM estimates
Minimum
0.0072
Mean
0.0425
Maximum
0.28
Median
0.0255
SD
0.0648
CV
1.526
k hat (MLE)
1.207
k star (bias corrected MLE)
1.023
Theta hat (MLE)
0.0352
Theta star (bias corrected MLE)
0.0415
nu hat (MLE)
38.64
nu star (bias corrected)
32.73
MLE Mean (bias corrected)
0.0425
MLE Sd (bias corrected)
0.042
95% Percentile of Chisquare (2kstar)
6.079
90% Percentile
0.0972
95% Percentile
0.126
99% Percentile
0.193
The following statistics are computed using Gamma ROS Statistics on Imputed Data
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW

95% Approx. Gamma UTL with 95% Coverage
0.195
0.2
95% Approx. Gamma UPL
0.128
0.126
95% Gamma USL
0.187
0.19
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.0421
SD (KM)
0.0629
Variance (KM)
0.00396
SE of Mean (KM)
0.0164
k hat (KM)
0.448
k star (KM)
0.405
nu hat (KM)
14.33
nu star (KM)
12.97
theta hat (KM)
0.094
theta star (KM)
0.104
80% gamma percentile (KM)
0.068
90% gamma percentile (KM)
0.119
95% gamma percentile (KM)
0.174
99% gamma percentile (KM)
0.313
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.193
0.2
95% Approx. Gamma UPL
0.126
0.125
95% KM Gamma Percentile
0.113
0.112
95% Gamma USL
0.185
0.19
Lognormal GOF Test on Detected Observations Only
Shapiro Wilk Test Statistic
0.844
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.866
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.227
Lilliefors GOF Test
5% Lilliefors Critical Value
0.234
Detected Data appear Lognormal at 5% Significance Level
Detected Data appear Approximate Lognormal at 5% Significance Level
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.0419
Mean in Log Scale
-3.691
SD in Original Scale
0.065
SD in Log Scale
0.958
95% UTL95% Coverage
0.28
95% BCA UTL95% Coverage
0.28
95% Bootstrap (%) UTL95% Coverage
0.28
95% UPL (t)
0.141
90% Percentile (z)
0.0852
95% Percentile (z)
0.121
99% Percentile (z)
0.232
95% USL
0.259
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-3.68
95% KM UTL (Lognormal)95% Coverage
0.256
KM SD of Logged Data
0.918
95% KM UPL (Lognormal)
0.133
95% KM Percentile Lognormal (z)
0.114
95% KM USL (Lognormal)
0.238
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
0.0421
Mean in Log Scale
-3.687
SD in Original Scale
0.065
SD in Log Scale
0.979
95% UTL95% Coverage
0.296
95% UPL (t)
0.147
90% Percentile (z)
0.0878
95% Percentile (z)
0.125
99% Percentile (z)
0.244
95% USL
0.274
DU2 is not a Recommended Method. DU2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data appear to follow a Discernible Distribution at 5% Significance Level
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)

Order of Statistic, r
16
95% UTL with95% Coverage
0.28
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% UPL
0.28
95% USL
0.28
95% KM Chebyshev UPL
0.325
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
nickel
General Statistics
Total Number of Observations
16
Number of Distinct Observations
14
Minimum
4.9
First Quartile
5.35
Second Largest
12.8
Median
6.99
Maximum
20
Third Quartile
8.635
Mean
8.168
SD
4.026
Coefficient of Variation
0.493
Skewness
1.97
Mean of logged Data
2.014
SD of logged Data
0.404
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.767
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.227
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data Not Normal at 5% Significance Level
Data Not Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
18.33
90% Percentile (z)
13.33
95% UPL (t)
15.44
95% Percentile (z)
14.79
95% USL
18
99% Percentile (z)
17.53
Gamma GOF Test
A-D Test Statistic
0.845
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.741
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.192
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.216
Detected data appear Gamma Distributed at 5% Significance Level
Detected data follow Appr.
Gamma Distribution at 5% Significance Level
Gamma Statistics
k hat (MLE)
5.949
k star (bias corrected MLE)
4.876
Theta hat (MLE)
1.373
Theta star (bias corrected MLE)
1.675
nu hat (MLE)
190.4
nu star (bias corrected)
156
MLE Mean (bias corrected)
8.168
MLE Sd (bias corrected)
3.699

Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
15.39
90% Percentile
13.12
95% Hawkins Wixley (HW) Approx. Gamma UPL
15.41
95% Percentile
15.05
95% WH Approx. Gamma UTL with 95% Coverage
19.49
99% Percentile
19.12
95% HW Approx. Gamma UTL with 95% Coverage
19.74
95% WH USL
18.99
95% HW USL 19.22
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.884
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.18
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data appear Lognormal at 5% Significance Level
Data appear Approximate Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
20.77
90% Percentile (z)
12.57
95% UPL (t)
15.55
95% Percentile (z)
14.56
95% USL
20.11
99% Percentile (z)
19.18
Nonparametric Distribution Free Background Statistics
Data appear Approximate Gamma Distribution at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
20
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
20
95% BCA Bootstrap UTL with 95% Coverage
20
95% UPL
20
90% Percentile
12.8
90% Chebyshev UPL
20.62
95% Percentile
14.6
95% Chebyshev UPL
26.26
99% Percentile
18.92
95% USL
20
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
selenium
General Statistics
Total Number of Observations
16
Number of Missing Observations
0
Number of Distinct Observations
14
Number of Detects
12
Number of Non -Detects
4
Number of Distinct Detects
11
Number of Distinct Non -Detects
3
Minimum Detect
0.306
Minimum Non -Detect
0.53
Maximum Detect
1.7
Maximum Non -Detect
0.65
Variance Detected
0.258
Percent Non -Detects
25%
Mean Detected
0.986
SD Detected
0.508
Mean of Detected Logged Data
-0.157
SD of Detected Logged Data
0.582

Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test on Detects Only
Shapiro Wilk Test Statistic
0.895
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.859
Detected Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.214
Lilliefors GOF Test
5% Lilliefors Critical Value
0.243
Detected Data appear Normal at 5% Significance Level
Detected Data appear Normal at 5% Significance Level
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.854
KM SD
0.481
95% UTL95% Coverage
2.068
95% KM UPL (t)
1.724
90% KM Percentile (z)
1.471
95% KM Percentile (z)
1.646
99% KM Percentile (z)
1.973
95% KM USL
2.03
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
0.813
SD
0.534
95% UTL95% Coverage
2.16
95% UPL (t)
1.778
90% Percentile (z)
1.497
95% Percentile (z)
1.691
99% Percentile (z)
2.055
95% USL
2.117
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
A-D Test Statistic
0.53
Anderson -Darling GOF Test
5% A-D Critical Value
0.737
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.205
Kolmogorov-Smirnov GOF
5% K-S Critical Value
0.247
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics on Detected Data Only
k hat (MLE)
3.662
k star (bias corrected MLE)
2.802
Theta hat (MLE)
0.269
Theta star (bias corrected MLE)
0.352
nu hat (MLE)
87.88
nu star (bias corrected)
67.25
MLE Mean (bias corrected)
0.986
MLE Sd (bias corrected)
0.589
95% Percentile of Chisquare (2kstar) 12
Gamma ROS Statistics using Imputed Non -Detects
GROS may not be used when data set has > 50% NDs with many tied observations at multiple DLs
GROS may not be used when kstar of detects is small such as <1.0, especially when the sample size is small (e.g., <15-20)
For such situations, GROS method may yield incorrect values of UCLs and BTVs
This is especially true when the sample size is small.
For gamma distributed detected data, BTVs and UCLs may be computed using gamma distribution on KM estimates
Minimum
0.306
Mean
0.859
Maximum
1.7
Median
0.594
SD
0.493
CV
0.574
k hat (MLE)
3.391
k star (bias corrected MLE)
2.797
Theta hat (MLE)
0.253
Theta star (bias corrected MLE)
0.307
nu hat (MLE)
108.5
nu star (bias corrected)
89.5

MLE Mean (bias corrected)
0.859
MLE Sd (bias corrected)
0.514
95% Percentile of Chisquare (2kstar)
11.98
90% Percentile
1.548
95% Percentile
1.84
99% Percentile
2.476
The following statistics are computed using Gamma ROS Statistics on Imputed Data
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
2.562
2.667
95% Approx. Gamma UPL
1.909
1.943
95% Gamma USL
2.482
2.577
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.854
SD (KM)
0.481
Variance (KM)
0.231
SE of Mean (KM)
0.127
k hat (KM)
3.156
k star (KM)
2.606
nu hat (KM)
101
nu star (KM)
83.39
theta hat (KM)
0.271
theta star (KM)
0.328
80% gamma percentile (KM)
1.24
90% gamma percentile (KM)
1.564
95% gamma percentile (KM)
1.869
99% gamma percentile (KM)
2.534
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
2.503
2.604
95% Approx. Gamma UPL
1.871
1.903
95% KM Gamma Percentile
1.745
1.766
95% Gamma USL
2.426
2.516
Lognormal GOF Test on Detected Observations Only
Shapiro Wilk Test Statistic
0.906
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.859
Detected Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.181
Lilliefors GOF Test
5% Lilliefors Critical Value
0.243
Detected Data appear Lognormal at 5% Significance Level
Detected Data appear Lognormal at 5% Significance Level
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.859
Mean in Log Scale
-0.305
SD in Original Scale
0.492
SD in Log Scale
0.569
95% UTL95% Coverage
3.101
95% BCA UTL95% Coverage
1.7
95% Bootstrap (%) UTL95% Coverage
1.7
95% UPL (t)
2.062
90% Percentile (z)
1.529
95% Percentile (z)
1.88
99% Percentile (z)
2.771
95% USL
2.962
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-0.317
95% KM UTL (Lognormal)95% Coverage
3.053
KM SD of Logged Data
0.568
95% KM UPL (Lognormal)
2.032
95% KM Percentile Lognormal (z)
1.853
95% KM USL (Lognormal)
2.916
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
0.813
Mean in Log Scale
-0.424
SD in Original Scale
0.534
SD in Log Scale
0.691
95% UTL95% Coverage
3.74
95% UPL (t)
2.28
90% Percentile (z)
1.586
95% Percentile (z)
2.038
99% Percentile (z)
1 3.263
1 95% USL
3.538

DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data appear to follow a Discernible Distribution at 5% Significance Level
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
16
95% UTL with95% Coverage
1.7
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% UPL
1.7
95% USL
1.7
95% KM Chebyshev UPL
3.016
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
strontium
General Statistics
Total Number of Observations
16
Number of Distinct Observations
13
Minimum
14
First Quartile
16.6
Second Largest
29
Median
19
Maximum
46
Third Quartile
24.55
Mean
21.7
SD
7.877
Coefficient of Variation
0.363
Skewness
2.078
Mean of logged Data
3.029
SD of logged Data
0.307
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.524 d2max (for USL) 2.443
Normal GOF Test
Shapiro Wilk Test Statistic
0.791
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.887
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.208
Lilliefors GOF Test
5% Lilliefors Critical Value
0.213
Data appear Normal at 5% Significance Level
Data appear Approximate Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
41.58
90% Percentile (z)
31.79
95% UPL (t)
35.93
95% Percentile (z)
34.66
95% USL
40.94
99% Percentile (z)
40.02
Gamma GOF Test
A-D Test Statistic
0.604
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.739
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.186
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.215
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level

Gamma Statistics
k hat (MLE)
10.41
k star (bias corrected MLE)
8.501
Theta hat (MLE)
2.084
Theta star (bias corrected MLE)
2.553
nu hat (MLE)
333.2
nu star (bias corrected)
272
MLE Mean (bias corrected)
21.7
MLE Sd (bias corrected)
7.443
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
35.79
90% Percentile
31.62
95% Hawkins Wixley (HW) Approx. Gamma UPL
35.82
95% Percentile
35.21
95% WH Approx. Gamma UTL with 95% Coverage
43.19
99% Percentile
42.64
95% HW Approx. Gamma UTL with 95% Coverage
43.54
95% WH USL
42.31
95% HW USL 42.61
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.91
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.887
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.17
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.213
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
44.88
90% Percentile (z)
30.64
95% UPL (t)
36
95% Percentile (z)
34.25
95% USL
43.78
99% Percentile (z)
42.23
Nonparametric Distribution Free Background Statistics
Data appear Approximate Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
16
95% UTL with 95% Coverage
46
Approx, f used to compute achieved CC
0.842
Approximate Actual Confidence Coefficient achieved by UTL
0.56
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
46
95% BCA Bootstrap UTL with 95% Coverage
46
95% UPL
46
90% Percentile
27.05
90% Chebyshev UPL
46.06
95% Percentile
33.25
95% Chebyshev UPL
57.09
99% Percentile
43.45
95% USL
46
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
thallium
General Statistics
Total Number of Observations
10
Number of Missing Observations
6
Number of Distinct Observations
8
Number of Detects
1
Number of Non -Detects
9

Number of Distinct Detects
1
Number of Distinct Non -Detects
7
Minimum Detect
2.3
Minimum Non -Detect
0.53
Maximum Detect
2.3
Maximum Non -Detect
0.65
Variance Detected
N/A
Percent Non -Detects
90%
Mean Detected
2.3
SD Detected
N/A
Mean of Detected Logged Data
0.833
SD of Detected Logged Data
N/A
Warning: Only one distinct data value was detected! ProUCL (or any other software) should not be used on such a data set!
It is suggested to use alternative site specific values determined by the Project Team to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable thallium was not processed!
vanadium
General Statistics
Total Number of Observations
10
Number of Distinct Observations
8
Number of Missing Observations
6
Minimum
34
First Quartile
35.5
Second Largest
67
Median
38.5
Maximum
190
Third Quartile
52.5
Mean
57.9
SD
47.63
Coefficient of Variation
0.823
Skewness
2.884
Mean of logged Data
3.89
SD of logged Data
0.527
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.911 d2max (for USL) 2.176
Normal GOF Test
Shapiro Wilk Test Statistic
0.548
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.842
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.341
Lilliefors GOF Test
5% Lilliefors Critical Value
0.262
Data Not Normal at 5% Significance Level
Data Not Norma! at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
196.6
90% Percentile (z)
118.9
95% UPL (t)
149.5
95% Percentile (z)
136.2
95% USL
161.5
99% Percentile (z)
168.7
Gamma GOF Test
A-D Test Statistic
1.459
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.732
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.285
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.268
Data Not Gamma Distributed at 5% Significance Level
Data Not Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
3.123
k star (bias corrected MLE)
2.253
Theta hat (MLE)
18.54
Theta star (bias corrected MLE)
25.7

nu hat (MLE)
62.46
nu star (bias corrected)
45.06
MLE Mean (bias corrected)
57.9
MLE Sd (bias corrected)
38.58
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
139.3
90% Percentile
109.5
95% Hawkins Wixley (HW) Approx. Gamma UPL
138.1
95% Percentile
132.3
95% WH Approx. Gamma UTL with 95% Coverage
209.5
99% Percentile
182.5
95% HW Approx. Gamma UTL with 95% Coverage
212.7
95% WH USL
155.5
95% HW USL 155
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.71
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.842
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.249
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.262
Data appear Lognormal at 5% Significance Level
Data appear Approximate Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
227
90% Percentile (z)
96.14
95% UPL (t)
134.8
95% Percentile (z)
116.4
95% USL
154.1
99% Percentile (z)
166.8
Nonparametric Distribution Free Background Statistics
Data appear Approximate Lognormal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
10
95% UTL with 95% Coverage
190
Approx, f used to compute achieved CC
0.526
Approximate Actual Confidence Coefficient achieved by UTL
0.401
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
190
95% BCA Bootstrap UTL with 95% Coverage
190
95% UPL
190
90% Percentile
79.3
90% Chebyshev UPL
207.8
95% Percentile
134.7
95% Chebyshev UPL
275.7
99% Percentile
178.9
95% USL
190
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
zinc
General Statistics
Total Number of Observations
10
Number of Distinct Observations
10
Number of Missing Observations
6
Minimum
40
First Quartile
44.25
Second Largest
75
Median
46.5
Maximum
230
Third Quartile
49.75
Mean
66.9
SD
58.12

Coefficient of Variation
0.869
Skewness
3.01
Mean of logged Data
4.028
SD of logged Data
0.524
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 2.911 d2max (for USL) 2.176
Normal GOF Test
Shapiro Wilk Test Statistic
0.485
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.842
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.414
Lilliefors GOF Test
5% Lilliefors Critical Value
0.262
Data Not Normal at 5% Significance Level
Data Not Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
236.1
90% Percentile (z)
141.4
95% UPL (t)
178.6
95% Percentile (z)
162.5
95% USL
193.4
99% Percentile (z)
202.1
Gamma GOF Test
A-D Test Statistic
2.033
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.732
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.412
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.268
Data Not Gamma Distributed at 5% Significance Level
Data Not Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
3.009
k star (bias corrected MLE)
2.173
Theta hat (MLE)
22.23
Theta star (bias corrected MLE)
30.79
nu hat (MLE)
60.18
nu star (bias corrected)
43.46
MLE Mean (bias corrected)
66.9
MLE Sd (bias corrected)
45.38
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
162.6
90% Percentile
127.6
95% Hawkins Wixley (HW) Approx. Gamma UPL
160.4
95% Percentile
154.6
95% WH Approx. Gamma UTL with 95% Coverage
245.8
99% Percentile
214.2
95% HW Approx. Gamma UTL with 95% Coverage
248.1
95% WH USL
181.7
95% HW USL 180.2
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.608
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.842
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.388
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.262
Data Not Lognormal at 5% Significance Level
Data Not Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
258
90% Percentile (z)
109.9
95% UPL (t)
153.7
95% Percentile (z)
132.9
95% USL
175.6
99% Percentile (z)
189.9

Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
10
95% UTL with 95% Coverage
230
Approx, f used to compute achieved CC
0.526
Approximate Actual Confidence Coefficient achieved by UTL
0.401
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
230
95% BCA Bootstrap UTL with 95% Coverage
230
95% UPL
230
90% Percentile
90.5
90% Chebyshev UPL
249.8
95% Percentile
160.3
95% Chebyshev UPL
332.6
99% Percentile
216.1
95% USL
230
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.

Goodness -of -Fit Test Statistics for Data Sets with Non -Detects
User Selected Options
Date/Time of Computation
ProUCL 5.18/17/2021 4:14:53 PM
From File
ProUCL Background Inputs.xls
Full Precision
OFF
Confidence Coefficient
0.95
antimony
Num Obs
Num Miss
Num Valid
Detects
NDs
% NDs
Raw Statistics
16
6
10
0
10
100.00%
Warning: All observations are Non -Detects (NDs), therefore all statistics and estimates should also be NDs!
Specifically, sample mean, UCLs, UPLs, and other statistics are also NDs lying below the largest detection limit!
The Project Team may decide to use alternative site specific values to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable antimony was not processed!
arsenic
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
13
Minimum
1.4
Maximum
3.08
Mean of Raw Data
1.997
Standard Deviation of Raw Data
0.376
Khat
33.27
Theta hat
0.06
Kstar
27.08
Theta star
0.0737
Mean of Log Transformed Data
0.676
Standard Deviation of Log Transformed Data
0.176
Normal GOF Test Results
Correlation Coefficient R
0.929
Shapiro Wilk Test Statistic
0.887
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.039
Lilliefors Test Statistic
0.147
Lilliefors Critical (0.05) Value
0.213
Data appear Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.948

A-D Test Statistic
0.399
A-D Critical (0.05) Value
0.736
K-S Test Statistic
0.124
K-S Critical(0.05) Value
0.215
Data appear Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.963
Shapiro Wilk Test Statistic
0.948
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.368
Lilliefors Test Statistic
0.125
Lilliefors Critical (0.05) Value
0.213
Data appear Lognormal at (0.05) Significance Level
barium
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
15
Minimum
36
Maximum
77.9
Mean of Raw Data
54.96
Standard Deviation of Raw Data
11.56
Khat
25.01
Theta hat
2.197
Kstar
20.36
Theta star
2.699
Mean of Log Transformed Data
3.986
Standard Deviation of Log Transformed Data
0.206
Normal GOF Test Results
Correlation Coefficient R
0.971
Shapiro Wilk Test Statistic
0.942
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.378
Lilliefors Test Statistic
0.192
Lilliefors Critical (0.05) Value
0.213
Data appear Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.981
A-D Test Statistic
0.321
A-D Critical (0.05) Value
0.736
K-S Test Statistic
0.17
K-S Critical(0.05) Value
0.215
Data appear Gamma Distributed at (0.05) Significance Level

Lognormal GOF Test Results
Correlation Coefficient R
0.984
Shapiro Wilk Test Statistic
0.968
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.779
Lilliefors Test Statistic
0.156
Lilliefors Critical (0.05) Value
0.213
Data appear Lognormal at (0.05) Significance Level
beryllium
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
14
Minimum
0.293
Maximum
0.99
Mean of Raw Data
0.507
Standard Deviation of Raw Data
0.154
Khat
14.04
Theta hat
0.0361
Kstar
11.45
Theta star
0.0443
Mean of Log Transformed Data
-0.715
Standard Deviation of Log Transformed Data
0.268
Normal GOF Test Results
Correlation Coefficient R
0.886
Shapiro Wilk Test Statistic
0.813
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.00264
Lilliefors Test Statistic
0.228
Lilliefors Critical (0.05) Value
0.213
Data not Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.92
A-D Test Statistic
0.558
A-D Critical (0.05) Value
0.738
K-S Test Statistic
0.185
K-S Critical(0.05) Value
0.215
Data appear Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.953
Shapiro Wilk Test Statistic
0.933

Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.206
Lilliefors Test Statistic
0.169
Lilliefors Critical (0.05) Value
0.213
Data appear Lognormal at (0.05) Significance Level
cadmium
Num Obs
Num Miss
Num Valid
Detects
NDs
% NDs
Raw Statistics
16
0
16
7
9
56.25%
Number
Minimum
Maximum
Mean
Median
SD
Statistics (Non -Detects Only)
9
0.27
0.3
0.283
0.28
0.0122
Statistics (Non -Detects Only)
7
0.0918
0.38
0.161
0.136
0.101
Statistics (All: NDs treated as DL value)
16
0.0918
0.38
0.23
0.27
0.09
Statistics (All: NDs treated as DL/2 value)
16
0.0918
0.38
0.15
0.14
0.0648
Statistics (Normal ROS Imputed Data)
16
0.0772
0.38
0.147
0.136
0.0725
Statistics (Gamma ROS Imputed Data)
16
0.0789
0.38
0.143
0.131
0.0718
Statistics (Lognormal ROS Imputed Data)
16
0.0918
0.38
0.143
0.131
0.0693
K hat
K Star
Theta hat
Log Mean
Log Stdv
Log CV
Statistics (Non -Detects Only)
4.282
2.542
0.0376
-1.948
0.491
-0.252
Statistics (NDs = DL)
5.628
4.614
0.0408
-1.562
0.47
-0.301
Statistics (NDs = DL/2)
9.164
7.487
0.0164
-1.952
0.312
-0.16
Statistics (Gamma ROS Estimates)
6.178
5.062
0.0231
-2.03
0.392
-0.193
Statistics (Lognormal ROS Estimates)
-2.02
0.358
-0.177
Normal GOF Test Results
No NDs
NDs = DL
NDs = DL/2Normal
RO
Correlation Coefficient R
0.832
0.936
0.729
0.849
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Shapiro -Wilk (Detects Only)
0.712
0.803
Data Not Normal
Shapiro -Wilk (NDs = DL)
0.866
0.887
Data Not Normal
Shapiro -Wilk (NDs = DL/2)
0.566
0.887
Data Not Normal
Shapiro -Wilk (Normal ROS Estimates)
0.742
0.887
Data Not Normal
Lilliefors (Detects Only)
0.3
0.304
Data Appear Normal
Lilliefors (NDs = DL)
0.297
0.213
Data Not Normal
Lilliefors (NDs = DL/2)
0.376
0.213
Data Not Normal
Lilliefors (Normal ROS Estimates)
0.215
0.213
Data Not Normal
Gamma GOF Test Results
No NDs
NDs = DL
NDs = DL/2
amma RO
Correlation Coefficient R
0.919
0.901
0.791
0.893
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Anderson -Darling (Detects Only)
0.646
0.71
Kolmogorov-Smirnov (Detects Only)
0.267
0.313
Detected Data Appear Gamma Distributed

Anderson -Darling (NDs = DL)
1.302
0.741
Kolmogorov-Smirnov (NDs = DL)
0.328
0.216
Data Not Gamma Distributed
Anderson -Darling (NDs = DL/2)
1.888
0.739
Kolmogorov-Smirnov (NDs = DL/2)
0.332
0.215
Data Not Gamma Distributed
Anderson -Darling (Gamma ROS Estimates)
0.81
0.741
Kolmogorov-Smirnov (Gamma ROS Est.)
0.165
0.216
Detected Data appear Approximate Gamma Dist
Lognormal GOF Test Results
No NDs
NDs = DL
NDs = DL/2
Log ROS
Correlation Coefficient R
0.918
0.916
0.846
0.905
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Shapiro -Wilk (Detects Only)
0.851
0.803
Data Appear Lognormal
Shapiro -Wilk (NDs = DL)
0.827
0.887
Data Not Lognormal
Shapiro -Wilk (NDs = DL/2)
0.748
0.887
Data Not Lognormal
Shapiro -Wilk (Lognormal ROS Estimates)
0.832
0.887
Data Not Lognormal
Lilliefors (Detects Only)
0.235
0.304
Data Appear Lognormal
Lilliefors (NDs = DL)
0.33
0.213
Data Not Lognormal
Lilliefors (NDs = DL/2)
0.305
0.213
Data Not Lognormal
Lilliefors (Lognormal ROS Estimates)
0.162
0.213
Data Appear Lognormal
Note: Substitution methods such as DL or DU2 are not recommended.
hexavalent chromium
Num Obs
Num Miss
Num Valid
Detects
NDs
% NDs
Raw Statistics
16
0
16
9
7
43.75%
Number
Minimum
Maximum
Mean
Median
SD
Statistics (Non -Detects Only)
7
0.12
1.19
0.863
1.14
0.504
Statistics (Non -Detects Only)
9
0.21
5.34
1.176
0.81
1.579
Statistics (All: NDs treated as DL value)
16
0.12
5.34
1.039
0.855
1.207
Statistics (All: NDs treated as DU2 value)
16
0.06
5.34
0.85
0.58
1.225
Statistics (Normal ROS Imputed Data)
16
-1.631
5.34
0.589
0.6
1.524
Statistics (Gamma ROS Imputed Data)
16
0.01
5.34
0.791
0.6
1.263
Statistics (Lognormal ROS Imputed Data)
16
0.13
5.34
0.836
0.6
1.23
K hat
K Star
Theta hat
Log Mean
Log Stdv
Log CV
Statistics (Non -Detects Only)
1.299
0.94
0.905
-0.27
0.867
-3.21
Statistics (NDs = DL)
1.38
1.163
0.753
-0.366
0.941
-2.571
Statistics (NDs = DL/2)
1.124
0.955
0.756
-0.669
1.045
-1.561
Statistics (Gamma ROS Estimates)
0.541
0.482
1.46
-1.394
2.029
-1.456
Statistics (Lognormal ROS Estimates)
-0.641
0.893
-1.394
Normal GOF Test Results
No NDs
NDs = DL
NDs = DU2Normal
RO
Correlation Coefficient R
0.705
0.73
0.659
0.853

Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Shapiro -Wilk (Detects Only)
0.531
0.829
Data Not Normal
Shapiro -Wilk (NDs = DL)
0.564
0.887
Data Not Normal
Shapiro -Wilk (NDs = DL/2)
0.467
0.887
Data Not Normal
Shapiro -Wilk (Normal ROS Estimates)
0.759
0.887
Data Not Normal
Lilliefors (Detects Only)
0.463
0.274
Data Not Normal
Lilliefors (NDs = DL)
0.388
0.213
Data Not Normal
Lilliefors (NDs = DL/2)
0.428
0.213
Data Not Normal
Lilliefors (Normal ROS Estimates)
0.308
0.213
Data Not Normal
Gamma GOF Test Results
No NDs
NDs = DL
NDs = DL/2
amma RO
Correlation Coefficient R
0.864
0.856
0.822
0.884
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Anderson -Darling (Detects Only)
1.129
0.738
Kolmogorov-Smirnov (Detects Only)
0.394
0.285
Data Not Gamma Distributed
Anderson -Darling (NDs = DL)
0.894
0.757
Kolmogorov-Smirnov (NDs = DL)
0.265
0.219
Data Not Gamma Distributed
Anderson -Darling (NDs = DL/2)
1.404
0.761
Kolmogorov-Smirnov (NDs = DL/2)
0.299
0.221
Data Not Gamma Distributed
Anderson -Darling (Gamma ROS Estimates)
1.083
0.793
Kolmogorov-Smirnov (Gamma ROS Est.)
0.234
0.227
Data Not Gamma Distributed
Lognormal GOF Test Results
No NDs
NDs = DL
NDs = DL/2
Log ROS
Correlation Coefficient R
0.904
0.938
0.904
0.942
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Shapiro -Wilk (Detects Only)
0.852
0.829
Data Appear Lognormal
Shapiro -Wilk (NDs = DL)
0.893
0.887
Data Appear Lognormal
Shapiro -Wilk (NDs = DL/2)
0.839
0.887
Data Not Lognormal
Shapiro -Wilk (Lognormal ROS Estimates)
0.902
0.887
Data Appear Lognormal
Lilliefors (Detects Only)
0.324
0.274
Data Not Lognormal
Lilliefors (NDs = DL)
0.221
0.213
Data Not Lognormal
Lilliefors (NDs = DL/2)
0.246
0.213
Data Not Lognormal
Lilliefors (Lognormal ROS Estimates)
0.22
0.213
Data Not Lognormal
Note: Substitution methods such as DL or DU2 are not recommended.
trivalent chromium
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
14
Minimum
16.16
Maximum
70.2
Mean of Raw Data
26.43

Standard Deviation of Raw Data
13.43
Khat
6.387
Theta hat
4.139
Kstar
5.231
Theta star
5.053
Mean of Log Transformed Data
3.194
Standard Deviation of Log Transformed Data
0.377
Normal GOF Test Results
Correlation Coefficient R
0.804
Shapiro Wilk Test Statistic
0.668
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
3.1044E-5
Lilliefors Test Statistic
0.307
Lilliefors Critical (0.05) Value
0.213
Data not Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.883
A-D Test Statistic
1.306
A-D Critical (0.05) Value
0.741
K-S Test Statistic
0.272
K-S Critical(0.05) Value
0.216
Data not Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.905
Shapiro Wilk Test Statistic
0.831
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.00584
Lilliefors Test Statistic
0.245
Lilliefors Critical (0.05) Value
0.213
Data not Lognormal at (0.05) Significance Level
Non -parametric GOF Test Results
Data do not follow a discernible distribution at (0.05) Level of Significan
total chromium
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
14
Minimum
16
Maximum
70.2
Mean of Raw Data
26.63
Standard Deviation of Raw Data
1 13.98

Khat
5.828
Theta hat
4.568
Kstar
4.777
Theta star
5.573
Mean of Log Transformed Data
3.194
Standard Deviation of Log Transformed Data
0.397
Normal GOF Test Results
Correlation Coefficient R
0.819
Shapiro Wilk Test Statistic
0.689
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
5.8616E-5
Lilliefors Test Statistic
0.31
Lilliefors Critical (0.05) Value
0.213
Data not Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.901
A-D Test Statistic
1.323
A-D Critical (0.05) Value
0.741
K-S Test Statistic
0.273
K-S Critical(0.05) Value
0.216
Data not Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.909
Shapiro Wilk Test Statistic
0.833
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.00674
Lilliefors Test Statistic
0.245
Lilliefors Critical (0.05) Value
0.213
Data not Lognormal at (0.05) Significance Level
Non -parametric GOF Test Results
Data do not follow a discernible distribution at (0.05) Level of Significan
cobalt
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
14
Minimum
6.3
Maximum
27
Mean of Raw Data
13.73
Standard Deviation of Raw Data
6.721
Khat
4.558

Theta hat
3.011
Kstar
3.745
Theta star
3.665
Mean of Log Transformed Data
2.506
Standard Deviation of Log Transformed Data
0.494
Normal GOF Test Results
Correlation Coefficient R
0.952
Shapiro Wilk Test Statistic
0.891
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.0725
Lilliefors Test Statistic
0.198
Lilliefors Critical (0.05) Value
0.213
Data appear Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.974
A-D Test Statistic
0.69
A-D Critical (0.05) Value
0.742
K-S Test Statistic
0.218
K-S Critical(0.05) Value
0.216
Data appear Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.959
Shapiro Wilk Test Statistic
0.9
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.108
Lilliefors Test Statistic
0.215
Lilliefors Critical (0.05) Value
0.213
Data appear Approximate -Lognormal at (0.05) Significance Level
copper
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
12
Minimum
15
Maximum
62.8
Mean of Raw Data
28.85
Standard Deviation of Raw Data
15.78
Khat
4.383
Theta hat
6.582
Kstar
3.603
Theta star
8.007
Mean of Log Transformed Data
3.244
Standard Deviation of Log Transformed Data
1 0.482

Normal GOF Test Results
Correlation Coefficient R
0.9
Shapiro Wilk Test Statistic
0.801
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.00266
Lilliefors Test Statistic
0.213
Lilliefors Critical (0.05) Value
0.213
Data appear Approximate Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.957
A-D Test Statistic
0.943
A-D Critical (0.05) Value
0.742
K-S Test Statistic
0.212
K-S Critical(0.05) Value
0.216
Data follow Appr. Gamma Distribution at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.945
Shapiro Wilk Test Statistic
0.876
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.0423
Lilliefors Test Statistic
0.206
Lilliefors Critical (0.05) Value
0.213
Data appear Approximate —Lognormal at (0.05) Significance Level
lead
Raw Statistics
Number of Valid Observations
10
Number of Missing Observations
6
Number of Distinct Observations
9
Minimum
0.55
Maximum
43
Mean of Raw Data
22.76
Standard Deviation of Raw Data
12.49
Khat
1.383
Theta hat
16.46
Kstar
1.034
Theta star
22
Mean of Log Transformed Data
2.721
Standard Deviation of Log Transformed Data
1.328
Normal GOF Test Results
Correlation Coefficient R
0.95

Shapiro Wilk Test Statistic
0.912
Shapiro Wilk Critical (0.05) Value
0.842
Approximate Shapiro Wilk P Value
0.242
Lilliefors Test Statistic
0.244
Lilliefors Critical (0.05) Value
0.262
Data appear Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.86
A-D Test Statistic
1.256
A-D Critical (0.05) Value
0.741
K-S Test Statistic
0.377
K-S Critical(0.05) Value
0.272
Data not Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.809
Shapiro Wilk Test Statistic
0.676
Shapiro Wilk Critical (0.05) Value
0.842
Approximate Shapiro Wilk P Value
4.1142E-4
Lilliefors Test Statistic
0.396
Lilliefors Critical (0.05) Value
0.262
Data not Lognormal at (0.05) Significance Level
manganese
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
13
Minimum
310
Maximum
940
Mean of Raw Data
547.3
Standard Deviation of Raw Data
182.1
Khat
10.67
Theta hat
51.31
Kstar
8.708
Theta star
62.85
Mean of Log Transformed Data
6.257
Standard Deviation of Log Transformed Data
0.313
Normal GOF Test Results
Correlation Coefficient R
0.925
Shapiro Wilk Test Statistic
0.854
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.0161
Lilliefors Test Statistic
0.295
Lilliefors Critical (0.05) Value
0.213

Data not Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.953
A-D Test Statistic
1.03
A-D Critical (0.05) Value
0.739
K-S Test Statistic
0.281
K-S Critical(0.05) Value
0.215
Data not Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.948
Shapiro Wilk Test Statistic
0.896
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.075
Lilliefors Test Statistic
0.264
Lilliefors Critical (0.05) Value
0.213
Data appear Approximate -Lognormal at (0.05) Significance Level
mercury
Num Obs
Num Miss
Num Valid
Detects
NDs
% NDs
Raw Statistics
16
0
16
13
3
18.75%
Number
Minimum
Maximum
Mean
Median
SD
Statistics (Non -Detects Only)
3
0.0067
0.023
0.0166
0.02
0.00868
Statistics (Non -Detects Only)
13
0.0072
0.28
0.0499
0.032
0.0701
Statistics (All: NDs treated as DL value)
16
0.0067
0.28
0.0437
0.0255
0.0642
Statistics (All: NDs treated as DU2 value)
16
0.00335
0.28
0.0421
0.0255
0.065
Statistics (Normal ROS Imputed Data)
16
-0.0704
0.28
0.0312
0.0255
0.0749
Statistics (Gamma ROS Imputed Data)
16
0.0072
0.28
0.0425
0.0255
0.0648
Statistics (Lognormal ROS Imputed Data)
16
0.00522
0.28
0.0419
0.0255
0.065
K hat
K Star
Theta hat
Log Mean
Log Stdv
Log CV
Statistics (Non -Detects Only)
1.377
1.111
0.0363
-3.402
0.807
-0.237
Statistics (NDs = DL)
1.314
1.11
0.0332
-3.557
0.833
-0.234
Statistics (NDs = DL/2)
1.098
0.934
0.0384
-3.687
0.979
-0.265
Statistics (Gamma ROS Estimates)
1.207
1.023
0.0352
-3.628
0.87
-0.24
Statistics (Lognormal ROS Estimates)
-3.691
0.958
-0.26
Normal GOF Test Results
No NDs
NDs = DL
NDs = DL/2Normal
RO
Correlation Coefficient R
0.661
0.647
0.666
0.806
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Shapiro -Wilk (Detects Only)
0.471
0.866
Data Not Normal
Shapiro -Wilk (NDs = DL)
0.451
0.887
Data Not Normal

Shapiro -Wilk (NDs = DL/2)
0.475
0.887
Data Not Normal
Shapiro -Wilk (Normal ROS Estimates)
0.686
0.887
Data Not Normal
Lilliefors (Detects Only)
0.4
0.234
Data Not Normal
Lilliefors (NDs = DL)
0.374
0.213
Data Not Normal
Lilliefors (NDs = DL/2)
0.365
0.213
Data Not Normal
Lilliefors (Normal ROS Estimates)
0.318
0.213
Data Not Normal
Gamma GOF Test Results
No NDs
NDs = DL
NDs = DL/2
amma RO
Correlation Coefficient R
0.829
0.817
0.84
0.832
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Anderson -Darling (Detects Only)
1.525
0.752
Kolmogorov-Smirnov (Detects Only)
0.279
0.241
Data Not Gamma Distributed
Anderson -Darling (NDs = DL)
1.554
0.758
Kolmogorov-Smirnov (NDs = DL)
0.247
0.22
Data Not Gamma Distributed
Anderson -Darling (NDs = DL/2)
1.06
0.762
Kolmogorov-Smirnov (NDs = DL/2)
0.223
0.221
Data Not Gamma Distributed
Anderson -Darling (Gamma ROS Estimates)
1.267
0.76
Kolmogorov-Smirnov (Gamma ROS Est.)
0.231
0.22
Data Not Gamma Distributed
Lognormal GOF Test Results
No NDs
NDs = DL
NDs = DL/2
Log ROS
Correlation Coefficient R
0.897
0.915
0.952
0.948
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Shapiro -Wilk (Detects Only)
0.844
0.866
Data Not Lognormal
Shapiro -Wilk (NDs = DL)
0.864
0.887
Data Not Lognormal
Shapiro -Wilk (NDs = DL/2)
0.93
0.887
Data Appear Lognormal
Shapiro -Wilk (Lognormal ROS Estimates)
0.912
0.887
Data Appear Lognormal
Lilliefors (Detects Only)
0.227
0.234
Data Appear Lognormal
Lilliefors (NDs = DL)
0.21
0.213
Data Appear Lognormal
Lilliefors (NDs = DL/2)
0.197
0.213
Data Appear Lognormal
Lilliefors (Lognormal ROS Estimates)
0.198
0.213
Data Appear Lognormal
Note: Substitution methods such as DL or DU2 are not recommended.
nickel
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
14
Minimum
4.9
Maximum
20
Mean of Raw Data
8.168
Standard Deviation of Raw Data
4.026
Khat
5.949
Theta hat
1 1.373

Kstar
4.876
Theta star
1.675
Mean of Log Transformed Data
2.014
Standard Deviation of Log Transformed Data
0.404
Normal GOF Test Results
Correlation Coefficient R
0.87
Shapiro Wilk Test Statistic
0.767
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
6.9828E-4
Lilliefors Test Statistic
0.227
Lilliefors Critical (0.05) Value
0.213
Data not Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.938
A-D Test Statistic
0.845
A-D Critical (0.05) Value
0.741
K-S Test Statistic
0.192
K-S Critical(0.05) Value
0.216
Data follow Appr. Gamma Distribution at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.942
Shapiro Wilk Test Statistic
0.884
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.0484
Lilliefors Test Statistic
0.18
Lilliefors Critical (0.05) Value
0.213
Data appear Approximate -Lognormal at (0.05) Significance Level
selenium
Num Obs
Num Miss
Num Valid
Detects
NDs
% NDs
Raw Statistics
16
0
16
12
4
25.00%
Number
Minimum
Maximum
Mean
Median
SD
Statistics (Non -Detects Only)
4
0.53
0.65
0.59
0.59
0.049
Statistics (Non -Detects Only)
12
0.306
1.7
0.986
0.964
0.508
Statistics (All: NDs treated as DL value)
16
0.306
1.7
0.887
0.62
0.47
Statistics (All: NDs treated as DU2 value)
16
0.265
1.7
0.813
0.553
0.534
Statistics (Normal ROS Imputed Data)
16
0.306
1.7
0.859
0.617
0.495
Statistics (Gamma ROS Imputed Data)
16
0.306
1.7
0.859
0.594
0.493
Statistics (Lognormal ROS Imputed Data)
16
0.306
1.7
0.859
0.578
0.492
K hat
K Star
Theta hat
Log Mean
Log Stdv
Log CV
Statistics (Non -Detects Only)
3.662
1 2.802
0.269
-0.157
0.582
-3.698

Statistics (NDs = DL)
3.999
3.291
0.222
-0.251
0.527
-2.102
Statistics (NDs = DL/2)
2.462
2.042
0.33
-0.424
0.691
-1.629
Statistics (Gamma ROS Estimates)
3.391
2.797
0.253
-0.307
0.574
-1.874
Statistics (Lognormal ROS Estimates)
-0.305
0.569
-1.868
Normal GOF Test Results
No NDs
NDs = DL
NDs = DL/2Normal
RO
Correlation Coefficient R
0.958
0.931
0.933
0.939
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Shapiro -Wilk (Detects Only)
0.895
0.859
Data Appear Normal
Shapiro -Wilk (NDs = DL)
0.852
0.887
Data Not Normal
Shapiro -Wilk (NDs = DL/2)
0.848
0.887
Data Not Normal
Shapiro -Wilk (Normal ROS Estimates)
0.862
0.887
Data Not Normal
Lilliefors (Detects Only)
0.214
0.243
Data Appear Normal
Lilliefors (NDs = DL)
0.255
0.213
Data Not Normal
Lilliefors (NDs = DL/2)
0.243
0.213
Data Not Normal
Lilliefors (Normal ROS Estimates)
0.226
0.213
Data Not Normal
Gamma GOF Test Results
No NDs
NDs = DL
NDs = DL/2
amma RO
Correlation Coefficient R
0.941
0.952
0.948
0.953
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Anderson -Darling (Detects Only)
0.53
0.737
Kolmogorov-Smirnov (Detects Only)
0.205
0.247
Detected Data Appear Gamma Distributed
Anderson -Darling (NDs = DL)
0.833
0.742
Kolmogorov-Smirnov (NDs = DL)
0.225
0.216
Data Not Gamma Distributed
Anderson -Darling (NDs = DL/2)
0.755
0.748
Kolmogorov-Smirnov (NDs = DL/2)
0.19
0.217
Detected Data appear Approximate Gamma Dist
Anderson -Darling (Gamma ROS Estimates)
0.759
0.743
Kolmogorov-Smirnov (Gamma ROS Est.)
0.206
0.216
Detected Data appear Approximate Gamma Dist
Lognormal GOF Test Results
No NDs
NDs = DL
NDs = DL/2
Log ROS
Correlation Coefficient R
0.961
0.959
0.955
0.959
Test value
Crit. (0.05)
Conclusion with Alpha(0.05)
Shapiro -Wilk (Detects Only)
0.906
0.859
Data Appear Lognormal
Shapiro -Wilk (NDs = DL)
0.909
0.887
Data Appear Lognormal
Shapiro -Wilk (NDs = DL/2)
0.887
0.887
Data Not Lognormal
Shapiro -Wilk (Lognormal ROS Estimates)
0.901
0.887
Data Appear Lognormal
Lilliefors (Detects Only)
0.181
0.243
Data Appear Lognormal
Lilliefors (NDs = DL)
0.201
0.213
Data Appear Lognormal
Lilliefors (NDs = DL/2)
0.157
0.213
Data Appear Lognormal
Lilliefors (Lognormal ROS Estimates)
0.211
0.213
Data Appear Lognormal

Note: Substitution methods such as DL or DL/2 are not recommended.
strontium
Raw Statistics
Number of Valid Observations
16
Number of Distinct Observations
13
Minimum
14
Maximum
46
Mean of Raw Data
21.7
Standard Deviation of Raw Data
7.877
Khat
10.41
Theta hat
2.084
Kstar
8.501
Theta star
2.553
Mean of Log Transformed Data
3.029
Standard Deviation of Log Transformed Data
0.307
Normal GOF Test Results
Correlation Coefficient R
0.879
Shapiro Wilk Test Statistic
0.791
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.00141
Lilliefors Test Statistic
0.208
Lilliefors Critical (0.05) Value
0.213
Data appear Approximate Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.926
A-D Test Statistic
0.604
A-D Critical (0.05) Value
0.739
K-S Test Statistic
0.186
K-S Critical(0.05) Value
0.215
Data appear Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.951
Shapiro Wilk Test Statistic
0.91
Shapiro Wilk Critical (0.05) Value
0.887
Approximate Shapiro Wilk P Value
0.112
Lilliefors Test Statistic
0.17
Lilliefors Critical (0.05) Value
0.213
Data appear Lognormal at (0.05) Significance Level
thallium
Num Obs
Num Miss
Num Valid
Detects
NDs
% NDs

Raw Statistics
16
1 6
1 10
1 1
1 9
90.00%
Warning: Only one distinct data value was detected! ProUCL (or any other software) should not be used on such a data set!
It is suggested to use alternative site specific values determined by the Project Team to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable thallium was not processed!
vanadium
Raw Statistics
Number of Valid Observations
10
Number of Missing Observations
6
Number of Distinct Observations
8
Minimum
34
Maximum
190
Mean of Raw Data
57.9
Standard Deviation of Raw Data
47.63
Khat
3.123
Theta hat
18.54
Kstar
2.253
Theta star
25.7
Mean of Log Transformed Data
3.89
Standard Deviation of Log Transformed Data
0.527
Normal GOF Test Results
Correlation Coefficient R
0.721
Shapiro Wilk Test Statistic
0.548
Shapiro Wilk Critical (0.05) Value
0.842
Approximate Shapiro Wilk P Value
1.7634E-5
Lilliefors Test Statistic
0.341
Lilliefors Critical (0.05) Value
0.262
Data not Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.847
A-D Test Statistic
1.459
A-D Critical (0.05) Value
0.732
K-S Test Statistic
0.285
K-S Critical(0.05) Value
0.268
Data not Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.832
Shapiro Wilk Test Statistic
0.71
Shapiro Wilk Critical (0.05) Value
0.842

Approximate Shapiro Wilk P Value
0.00103
Lilliefors Test Statistic
0.249
Lilliefors Critical (0.05) Value
0.262
Data appear Approximate -Lognormal at (0.05) Significance Level
zinc
Raw Statistics
Number of Valid Observations
10
Number of Missing Observations
6
Number of Distinct Observations
10
Minimum
40
Maximum
230
Mean of Raw Data
66.9
Standard Deviation of Raw Data
58.12
Khat
3.009
Theta hat
22.23
Kstar
2.173
Theta star
30.79
Mean of Log Transformed Data
4.028
Standard Deviation of Log Transformed Data
0.524
Normal GOF Test Results
Correlation Coefficient R
0.674
Shapiro Wilk Test Statistic
0.485
Shapiro Wilk Critical (0.05) Value
0.842
Approximate Shapiro Wilk P Value
4.0927E-6
Lilliefors Test Statistic
0.414
Lilliefors Critical (0.05) Value
0.262
Data not Normal at (0.05) Significance Level
Gamma GOF Test Results
Correlation Coefficient R
0.809
A-D Test Statistic
2.033
A-D Critical (0.05) Value
0.732
K-S Test Statistic
0.412
K-S Critical(0.05) Value
0.268
Data not Gamma Distributed at (0.05) Significance Level
Lognormal GOF Test Results
Correlation Coefficient R
0.762
Shapiro Wilk Test Statistic
0.608
Shapiro Wilk Critical (0.05) Value
0.842
Approximate Shapiro Wilk P Value
7.2387E-5
Lilliefors Test Statistic
0.388
Lilliefors Critical (0.05) Value
0.262
Data not Lognormal at (0.05) Significance Level

Non -parametric GOF Test Results
Data do not follow a discernible distribution at (0.05) Level of Significan

Outlier Tests for Selected Variables excluding nondetects
User Selected Options
Date/Time of Computation ProUCL 5.19/2/2021 1:32:32 PM
From File
ProUCL Background Inputs.xls
Full Precision
OFF
No Outlier Test for antimony
Dixon's Outlier Test for arsenic
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 3.08 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.572
For 10% significance level, 3.08 is an outlier.
For 5% significance level, 3.08 is an outlier.
For 1 % significance level, 3.08 is not an outlier.
2. Data Value 1.4 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.337
For 10% significance level, 1.4 is not an outlier.
For 5% significance level, 1.4 is not an outlier.
For 1 % significance level, 1.4 is not an outlier.
Dixon's Outlier Test for barium
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 77.9 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.353

For 10% significance level, 77.9 is not an outlier.
For 5% significance level, 77.9 is not an outlier.
For 1 % significance level, 77.9 is not an outlier.
2. Data Value 36 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.297
For 10% significance level, 36 is not an outlier.
For 5% significance level, 36 is not an outlier.
For 1 % significance level, 36 is not an outlier.
Dixon's Outlier Test for beryllium
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 0.99 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.650
For 10% significance level, 0.99 is an outlier.
For 5% significance level, 0.99 is an outlier.
For 1 % significance level, 0.99 is an outlier.
2. Data Value 0.293 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.316
For 10% significance level, 0.293 is not an outlier.
For 5% significance level, 0.293 is not an outlier.
For 1 % significance level, 0.293 is not an outlier.
Dixon's Outlier Test for cadmium
Total N = 16
Number NDs = 9
Number Detects = 7
10% critical value: 0.434
5% critical value: 0.507
1 % critical value: 0.637
Note: NDs excluded from Outlier Test

1. Data Value 0.38 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.704
For 10% significance level, 0.38 is an outlier.
For 5% significance level, 0.38 is an outlier.
For 1 % significance level, 0.38 is an outlier.
2. Data Value 0.0918 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.011
For 10% significance level, 0.0918 is not an outlier.
For 5% significance level, 0.0918 is not an outlier.
For 1 % significance level, 0.0918 is not an outlier.
Dixon's Outlier Test for hexavalent chromium
Total N = 16
Number NDs = 7
Number Detects = 9
10% critical value: 0.441
5% critical value: 0.512
1 % critical value: 0.635
Note: NDs excluded from Outlier Test
1. Data Value 5.34 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.908
For 10% significance level, 5.34 is an outlier.
For 5% significance level, 5.34 is an outlier.
For 1 % significance level, 5.34 is an outlier.
2. Data Value 0.21 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.328
For 10% significance level, 0.21 is not an outlier.
For 5% significance level, 0.21 is not an outlier.
For 1 % significance level, 0.21 is not an outlier.
Dixon's Outlier Test for trivalent chromium
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454

5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 70.2 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.608
For 10% significance level, 70.2 is an outlier.
For 5% significance level, 70.2 is an outlier.
For 1 % significance level, 70.2 is an outlier.
2. Data Value 16.16 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.064
For 10% significance level, 16.16 is not an outlier.
For 5% significance level, 16.16 is not an outlier.
For 1 % significance level, 16.16 is not an outlier.
Dixon's Outlier Test for total chromium
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 70.2 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.598
For 10% significance level, 70.2 is an outlier.
For 5% significance level, 70.2 is an outlier.
For 1 % significance level, 70.2 is an outlier.
2. Data Value 16 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.087
For 10% significance level, 16 is not an outlier.
For 5% significance level, 16 is not an outlier.
For 1 % significance level, 16 is not an outlier.
Dixon's Outlier Test for cobalt

Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 27 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.265
For 10% significance level, 27 is not an outlier.
For 5% significance level, 27 is not an outlier.
For 1 % significance level, 27 is not an outlier.
2. Data Value 6.3 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.071
For 10% significance level, 6.3 is not an outlier.
For 5% significance level, 6.3 is not an outlier.
For 1 % significance level, 6.3 is not an outlier.
Dixon's Outlier Test for copper
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 62.8 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.295
For 10% significance level, 62.8 is not an outlier.
For 5% significance level, 62.8 is not an outlier.
For 1 % significance level, 62.8 is not an outlier.
2. Data Value 15 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.029
For 10% significance level, 15 is not an outlier.
For 5% significance level, 15 is not an outlier.
For 1 % significance level, 15 is not an outlier.

Dixon's Outlier Test for lead
Total N = 10
Number NDs = 0
Number Detects = 10
10% critical value: 0.409
5% critical value: 0.477
1 % critical value: 0.597
Note: NDs excluded from Outlier Test
1. Data Value 43 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.282
For 10% significance level, 43 is not an outlier.
For 5% significance level, 43 is not an outlier.
For 1 % significance level, 43 is not an outlier.
2. Data Value 0.55 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.110
For 10% significance level, 0.55 is not an outlier.
For 5% significance level, 0.55 is not an outlier.
For 1 % significance level, 0.55 is not an outlier.
Dixon's Outlier Test for manganese
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 940 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.342
For 10% significance level, 940 is not an outlier.
For 5% significance level, 940 is not an outlier.
For 1 % significance level, 940 is not an outlier.
2. Data Value 310 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.223

For 10% significance level, 310 is not an outlier.
For 5% significance level, 310 is not an outlier.
For 1 % significance level, 310 is not an outlier.
Dixon's Outlier Test for mercury
Total N = 16
Number NDs = 3
Number Detects = 13
10% critical value: 0.467
5% critical value: 0.521
1 % critical value: 0.615
Note: NDs excluded from Outlier Test
1. Data Value 0.28 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.911
For 10% significance level, 0.28 is an outlier.
For 5% significance level, 0.28 is an outlier.
For 1 % significance level, 0.28 is an outlier.
2. Data Value 0.0072 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.338
For 10% significance level, 0.0072 is not an outlier.
For 5% significance level, 0.0072 is not an outlier.
For 1 % significance level, 0.0072 is not an outlier.
Dixon's Outlier Test for nickel
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 20 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.483
For 10% significance level, 20 is an outlier.
For 5% significance level, 20 is not an outlier.
For 1 % significance level, 20 is not an outlier.

2. Data Value 4.9 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.025
For 10% significance level, 4.9 is not an outlier.
For 5% significance level, 4.9 is not an outlier.
For 1 % significance level, 4.9 is not an outlier.
Dixon's Outlier Test for selenium
Total N = 16
Number NDs = 4
Number Detects = 12
10% critical value: 0.49
5% critical value: 0.546
1 % critical value: 0.642
Note: NDs excluded from Outlier Test
1. Data Value 1.7 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.082
For 10% significance level, 1.7 is not an outlier.
For 5% significance level, 1.7 is not an outlier.
For 1 % significance level, 1.7 is not an outlier.
2. Data Value 0.306 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.151
For 10% significance level, 0.306 is not an outlier.
For 5% significance level, 0.306 is not an outlier.
For 1 % significance level, 0.306 is not an outlier.
Dixon's Outlier Test for strontium
Total N = 16
Number NDs = 0
Number Detects = 16
10% critical value: 0.454
5% critical value: 0.507
1 % critical value: 0.595
Note: NDs excluded from Outlier Test
1. Data Value 46 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.674

For 10% significance level, 46 is an outlier.
For 5% significance level, 46 is an outlier.
For 1 % significance level, 46 is an outlier.
2. Data Value 14 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.090
For 10% significance level, 14 is not an outlier.
For 5% significance level, 14 is not an outlier.
For 1 % significance level, 14 is not an outlier.
No Outlier Test for thallium
Dixon's Outlier Test for vanadium
Total N = 10
Number NDs = 0
Number Detects = 10
10% critical value: 0.409
5% critical value: 0.477
1 % critical value: 0.597
Note: NDs excluded from Outlier Test
1. Data Value 190 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.794
For 10% significance level, 190 is an outlier.
For 5% significance level, 190 is an outlier.
For 1 % significance level, 190 is an outlier.
2. Data Value 34 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.030
For 10% significance level, 34 is not an outlier.
For 5% significance level, 34 is not an outlier.
For 1 % significance level, 34 is not an outlier.
Dixon's Outlier Test for zinc
Total N = 10
Number NDs = 0
Number Detects = 10
10% critical value: 0.409
5% critical value: 0.477

1 % critical value: 0.597
Note: NDs excluded from Outlier Test
1. Data Value 230 is a Potential Outlier (Upper Tail)?
Test Statistic: 0.829
For 10% significance level, 230 is an outlier.
For 5% significance level, 230 is an outlier.
For 1 % significance level, 230 is an outlier.
2. Data Value 40 is a Potential Outlier (Lower Tail)?
Test Statistic: 0.086
For 10% significance level, 40 is not an outlier.
For 5% significance level, 40 is not an outlier.
For 1 % significance level, 40 is not an outlier.

Background Statistics for Data Sets with Non -Detects
User Selected Options
Date/Time of Computation
ProUCL 5.18/20/2021 9:53:58 AM
From File
ProUCL Background Inputs_b.xls
Full Precision
OFF
Confidence Coefficient
95%
Coverage
95%
Different or Future K Observations
1
Number of Bootstrap Operations
2000
antimony
General Statistics
Total Number of Observations
2
Number of Missing Observations
2
Number of Distinct Observations
2
Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
2
Minimum Detect
N/A
Minimum Non -Detect
0.32
Maximum Detect
N/A
Maximum Non -Detect
0.325
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable antimony was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
arsenic
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
1.2
First Quartile
1.763
Second Largest
2.3
Median
2.125
Maximum
2.38
Third Quartile
2.32
Mean
1.958
SD
0.538
Coefficient of Variation
0.275
Skewness
-1.363
Mean of logged Data
0.638
SD of logged Data
0.316
Critical Values for Background Threshold Values (BTUs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.87
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.244
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level

Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
4.727
90% Percentile (z)
2.648
95% UPL (t)
3.374
95% Percentile (z)
2.843
95% USL
2.745
99% Percentile (z)
3.21
Gamma GOF Test
A-D Test Statistic
0.468
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.657
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.279
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.395
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
14.82
k star (bias corrected MLE)
3.871
Theta hat (MLE)
0.132
Theta star (bias corrected MLE)
0.506
nu hat (MLE)
118.5
nu star (bias corrected)
30.96
MLE Mean (bias corrected)
1.958
MLE Sd (bias corrected)
0.995
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
3.878
90% Percentile
3.291
95% Hawkins Wixley (HW) Approx. Gamma UPL
3.973
95% Percentile
3.828
95% WH Approx. Gamma UTL with 95% Coverage
6.703
99% Percentile
4.976
95% HW Approx. Gamma UTL with 95% Coverage
7.191
95% WH USL
2.892
95% HW USL 2.917
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.83
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.288
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
9.598
90% Percentile (z)
2.835
95% UPL (t)
4.341
95% Percentile (z)
3.18
95% USL
3.002
99% Percentile (z)
3.943
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
2.38
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
2.38
90% Percentile
2.356
90% Chebyshev UPL
3.763
95% Percentile
2.368
95% Chebyshev UPL
4.581
1 99% Percentile
2.378

95% USL
1 2.38
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
barium
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
12
First Quartile
16.88
Second Largest
23.5
Median
21
Maximum
38.4
Third Quartile
27.23
Mean
23.1
SD
11.23
Coefficient of Variation
0.486
Skewness
0.995
Mean of logged Data
3.052
SD of logged Data
0.485
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.952
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.236
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
80.89
90% Percentile (z)
37.5
95% UPL (t)
52.66
95% Percentile (z)
41.58
95% USL
39.53
99% Percentile (z)
49.23
Gamma GOF Test
A-D Test Statistic
0.212
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.659
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.18
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.396
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
5.85
k star (bias corrected MLE)
1.629
Theta hat (MLE)
3.949
Theta star (bias corrected MLE)
14.18
nu hat (MLE)
46.8
nu star (bias corrected)
13.03
MLE Mean (bias corrected)
23.1
MLE Sd (bias corrected)
18.1
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
63.39
90% Percentile
47.18
95% Hawkins Wixley (HW) Approx. Gamma UPL
65.74
95% Percentile
58.55

95% WH Approx. Gamma UTL with 95% Coverage
134.8
99% Percentile 84.07
95% HW Approx. Gamma UTL with 95% Coverage
151.3
95% WH USL
41.31
95% HW USL 41.66
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.998
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.164
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
256.5
90% Percentile (z)
39.39
95% UPL (t)
75.81
95% Percentile (z)
46.98
95% USL
43.01
99% Percentile (z)
65.39
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
38.4
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
38.4
90% Percentile
33.93
90% Chebyshev UPL
60.78
95% Percentile
36.17
95% Chebyshev UPL
77.85
99% Percentile
37.95
95% USL
38.4
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
beryllium
General Statistics
Total Number of Observations
4
Number of Missing Observations
0
Number of Distinct Observations
4
Number of Detects
3
Number of Non -Detects
1
Number of Distinct Detects
3
Number of Distinct Non -Detects
1
Minimum Detect
0.249
Minimum Non -Detect
0.32
Maximum Detect
0.465
Maximum Non -Detect
0.32
Variance Detected
0.0146
Percent Non -Detects
25%
Mean Detected
0.326
SD Detected
0.121
Mean of Detected Logged Data
-1.163
SD of Detected Logged Data
0.345
Warning: Data set has only 3 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.

Critical Values for Background Threshold Values (BTUs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Shapiro Wilk Test Statistic
0.8
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.767
Detected Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.364
Lilliefors GOF Test
5% Lilliefors Critical Value
0.425
Detected Data appear Normal at 5% Significance Level
Detected Data appear Normal at 5% Significance Level
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.308
KM SD
0.0906
95% UTL95% Coverage
0.775
95% KM UPL (t)
0.547
90% KM Percentile (z)
0.425
95% KM Percentile (z)
0.457
99% KM Percentile (z)
0.519
95% KM USL
0.441
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
0.284
SD
0.129
95% UTL95% Coverage
0.947
95% UPL (t)
0.623
90% Percentile (z)
0.449
95% Percentile (z)
0.496
99% Percentile (z)
0.584
95% USL
0.473
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
12.11
k star (bias corrected MLE)
N/A
Theta hat (MLE)
0.0269
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
72.63
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (2kstar) N/A
Gamma ROS Statistics using Imputed Non -Detects
GROS may not be used when data set has > 50% NDs with many tied observations at multiple DLs
GROS may not be used when kstar of detects is small such as <1.0, especially when the sample size is small (e.g., <15-20)
For such situations, GROS method may yield incorrect values of UCLs and BTVs
This is especially true when the sample size is small.
For gamma distributed detected data, BTVs and UCLs may be computed using gamma distribution on KM estimates
Minimum
0.249
Mean
0.31
Maximum
0.465
Median
0.263
SD
0.103
CV
0.334
k hat (MLE)
14.23
k star (bias corrected MLE)
3.725
Theta hat (MLE)
0.0218
Theta star (bias corrected MLE)
0.0833
nu hat (MLE)
113.9
nu star (bias corrected)
29.8
MLE Mean (bias corrected)
0.31
MLE Sd (bias corrected)
0.161
95% Percentile of Chisquare (2kstar)
14.72
90% Percentile
0.526
95% Percentile
1 0.613
99% Percentile
0.8

The following statistics are computed using Gamma ROS Statistics on Imputed Data
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
1.083
1.135
95% Approx. Gamma UPL
0.621
0.628
95% Gamma USL
0.461
0.461
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.308
SD (KM)
0.0906
Variance (KM)
0.00821
SE of Mean (KM)
0.0556
k hat (KM)
11.59
k star (KM)
3.064
nu hat (KM)
92.7
nu star (KM)
24.51
theta hat (KM)
0.0266
theta star (KM)
0.101
80% gamma percentile (KM)
0.439
90% gamma percentile (KM)
0.545
95% gamma percentile (KM)
0.643
99% gamma percentile (KM)
0.857
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.947
0.983
95% Approx. Gamma UPL
0.571
0.575
95% KM Gamma Percentile
0.456
0.456
95% Gamma USL
0.437
0.436
Lognormal GOF Test on Detected Observations Only
Shapiro Wilk Test Statistic
0.817
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.767
Detected Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.356
Lilliefors GOF Test
5% Lilliefors Critical Value
0.425
Detected Data appear Lognormal at 5% Significance Level
Detected Data appear Lognormal at 5% Significance Level
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.31
Mean in Log Scale
-1.206
SD in Original Scale
0.103
SD in Log Scale
0.295
95% UTL95% Coverage
1.364
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
0.65
90% Percentile (z)
0.437
95% Percentile (z)
0.486
99% Percentile (z)
0.594
95% USL
0.461
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-1.213
95% KM UTL (Lognormal)95% Coverage
1.129
KM SD of Logged Data
0.259
95% KM UPL (Lognormal)
0.588
95% KM Percentile Lognormal (z)
0.456
95% KM USL (Lognormal)
0.434
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
0.284
Mean in Log Scale
-1.331
SD in Original Scale
0.129
SD in Log Scale
0.438
95% UTL95% Coverage
2.511
95% UPL (t)
0.836
90% Percentile (z)
0.463
95% Percentile (z)
0.543
99% Percentile (z)
1 0.732
95% USL
0.501
DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics

Data appear to follow a Discernible Distribution at 5% Significance Level
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
0.465
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
0.465
95% USL
0.465
95% KM Chebyshev UPL
0.75
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
cadmium
General Statistics
Total Number of Observations
4
Number of Missing Observations
0
Number of Distinct Observations
4
Number of Detects
0
Number of Non -Detects
4
Number of Distinct Detects
0
Number of Distinct Non -Detects
4
Minimum Detect
N/A
Minimum Non -Detect
0.32
Maximum Detect
N/A
Maximum Non -Detect
0.636
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: All observations are Non -Detects (NDs), therefore all statistics and estimates should also be NDs!
Specifically, sample mean, UCLs, UPLs, and other statistics are also NDs lying below the largest detection limit!
The Project Team may decide to use alternative site specific values to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable cadmium was not processed!
hexavalent chromium
General Statistics
Total Number of Observations
4
Number of Missing Observations
0
Number of Distinct Observations
4
Number of Detects
3
Number of Non -Detects
1
Number of Distinct Detects
3
Number of Distinct Non -Detects
1
Minimum Detect
0.24
Minimum Non -Detect
0.4
Maximum Detect
0.671
Maximum Non -Detect
0.4
Variance Detected
0.0467
Percent Non -Detects
25%
Mean Detected
0.446
SD Detected
0.216
Mean of Detected Logged Data
-0.892
SD of Detected Logged Data
0.515
Warning: Data set has only 3 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.

Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Shapiro Wilk Test Statistic
0.995
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.767
Detected Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.2
Lilliefors GOF Test
5% Lilliefors Critical Value
0.425
Detected Data appear Normal at 5% Significance Level
Detected Data appear Normal at 5% Significance Level
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.395
KM SD
0.177
95% UTL95% Coverage
1.305
95% KM UPL (t)
0.86
90% KM Percentile (z)
0.622
95% KM Percentile (z)
0.686
99% KM Percentile (z)
0.807
95% KM USL
0.654
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
0.385
SD
0.215
95% UTL95% Coverage
1.492
95% UPL (t)
0.951
90% Percentile (z)
0.661
95% Percentile (z)
0.739
99% Percentile (z)
0.885
95% USL
0.699
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
6.052
k star (bias corrected MLE)
N/A
Theta hat (MLE)
0.0738
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
36.31
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (2kstar) N/A
Gamma ROS Statistics using Imputed Non -Detects
GROS may not be used when data set has > 50% NDs with many tied observations at multiple DLs
GROS may not be used when kstar of detects is small such as <1.0, especially when the sample size is small (e.g., <15-20)
For such situations, GROS method may yield incorrect values of UCLs and BTVs
This is especially true when the sample size is small.
For gamma distributed detected data, BTVs and UCLs may be computed using gamma distribution on KM estimates
Minimum
0.22
Mean
0.39
Maximum
0.671
Median
0.334
SD
0.21
CV
0.538
k hat (MLE)
4.927
k star (bias corrected MLE)
1.398
Theta hat (MLE)
0.0791
Theta star (bias corrected MLE)
0.279
nu hat (MLE)
39.42
nu star (bias corrected)
11.19
MLE Mean (bias corrected)
0.39
MLE Sd (bias corrected)
0.33
95% Percentile of Chisquare (2kstar)
7.459
90% Percentile
0.826
95% Percentile
1 1.04
99% Percentile
1.523
The following statistics are computed using Gamma ROS Statistics on Imputed Data

Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
2.552
2.894
95% Approx. Gamma UPL
1.15
1.195
95% Gamma USL
0.727
0.733
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.395
SD (KM)
0.177
Variance (KM)
0.0313
SE of Mean (KM)
0.108
k hat (KM)
4.974
k star (KM)
1.41
nu hat (KM)
39.79
nu star (KM)
11.28
theta hat (KM)
0.0794
theta star (KM)
0.28
80% gamma percentile (KM)
0.615
90% gamma percentile (KM)
0.835
95% gamma percentile (KM)
1.05
99% gamma percentile (KM)
1.537
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
2.009
2.205
95% Approx. Gamma UPL
0.989
1.014
95% KM Gamma Percentile
0.709
0.714
95% Gamma USL
0.664
0.667
Lognormal GOF Test on Detected Observations Only
Shapiro Wilk Test Statistic
0.995
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.767
Detected Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.2
Lilliefors GOF Test
5% Lilliefors Critical Value
0.425
Detected Data appear Lognormal at 5% Significance Level
Detected Data appear Lognormal at 5% Significance Level
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.393
Mean in Log Scale
-1.031
SD in Original Scale
0.206
SD in Log Scale
0.505
95% UTL95% Coverage
4.796
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
1.347
90% Percentile (z)
0.681
95% Percentile (z)
0.818
99% Percentile (z)
1.155
95% USL
0.746
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-1.025
95% KM UTL (Lognormal)95% Coverage
3.309
KM SD of Logged Data
0.432
95% KM UPL (Lognormal)
1.118
95% KM Percentile Lognormal (z)
0.73
95% KM USL (Lognormal)
0.675
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
0.385
Mean in Log Scale
-1.071
SD in Original Scale
0.215
SD in Log Scale
0.553
95% UTL95% Coverage
5.895
95% UPL (t)
1.469
90% Percentile (z)
0.696
95% Percentile (z)
0.851
99% Percentile (z)
1 1.241
95% USL
0.769
DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data appear to follow a Discernible Distribution at 5% Significance Level

Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
0.671
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
0.671
95% USL
0.671
95% KM Chebyshev UPL
1.257
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
trivalent chromium
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
22.76
First Quartile
37.57
Second Largest
62.88
Median
52.69
Maximum
64.97
Third Quartile
63.4
Mean
48.28
SD
19.8
Coefficient of Variation
0.41
Skewness
-0.776
Mean of logged Data
3.797
SD of logged Data
0.488
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.894
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.27
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
150.1
90% Percentile (z)
73.66
95% UPL (t)
100.4
95% Percentile (z)
80.85
95% USL
77.24
99% Percentile (z)
94.35
Gamma GOF Test
A-D Test Statistic
0.401
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.658
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.297
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.396
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
6.447
k star (bias corrected MLE)
1.778
Theta hat (MLE)
7.488
Theta star (bias corrected MLE)
27.15
nu hat (MLE)
51.58
nu star (bias corrected)
14.23

MLE Mean (bias corrected)
48.28
1 MLE Sd (bias corrected) 36.2
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
127.5
90% Percentile
96.54
95% Hawkins Wixley (HW) Approx. Gamma UPL
133.7
95% Percentile
118.9
95% WH Approx. Gamma UTL with 95% Coverage
264.9
99% Percentile
168.8
95% HW Approx. Gamma UTL with 95% Coverage
301.4
95% WH USL
84.49
95% HW USL 85.86
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.866
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.259
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
548.8
90% Percentile (z)
83.33
95% UPL (t)
161
95% Percentile (z)
99.49
95% USL
91.02
99% Percentile (z)
138.7
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
64.97
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
64.97
90% Percentile
64.34
90% Chebyshev UPL
114.7
95% Percentile
64.66
95% Chebyshev UPL
144.8
99% Percentile
64.91
95% USL
64.97
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
total chromium
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
23
First Quartile
37.63
Second Largest
63.55
Median
53.03
Maximum
65.4
Third Quartile
64.01
Mean
48.61
SD
19.99
Coefficient of Variation
0.411
Skewness
-0.749
Mean of logged Data
1 3.804
SD of logged Data
0.487

Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.891
5% Shapiro Wilk Critical Value
0.748
Lilliefors Test Statistic
0.273
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Sign
Shapiro Wilk GOF Test
Data appear Normal at 5% Significance Level
Lilliefors GOF Test
Data appear Normal at 5% Significance Level
ce Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage 151.4 90% Percentile (z) 74.23
95% UPL (t) 101.2 95% Percentile (z) 81.49
95% USL 77.84 99% Percentile (z) 95.11
Gamma GOF Test
A-D Test Statistic 0.403 Anderson -Darling Gamma GOF Test
5% A-D Critical Value 0.658 Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic 0.3 Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value 0.396 Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
6.448
k star (bias corrected MLE)
1.779
Theta hat (MLE)
7.539
Theta star (bias corrected MLE)
27.33
nu hat (MLE)
51.58
nu star (bias corrected)
14.23
MLE Mean (bias corrected)
48.61
MLE Sd (bias corrected)
36.45
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
128.4
90% Percentile
97.21
95% Hawkins Wixley (HW) Approx. Gamma UPL
134.6
95% Percentile
119.7
95% WH Approx. Gamma UTL with 95% Coverage
266.7
99% Percentile
170
95% HW Approx. Gamma UTL with 95% Coverage
303.3
95% WH USL
85.08
95% HW USL 86.44
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.866
5% Shapiro Wilk Critical Value
0.748
Lilliefors Test Statistic
0.262
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Sign
Shapiro Wilk Lognormal GOF Test
Data appear Lognormal at 5% Significance Level
Lilliefors Lognormal GOF Test
Data appear Lognormal at 5% Significance Level
cance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage 550.8 90% Percentile (z) 83.84
95% UPL (t) 161.9 95% Percentile (z) 100.1
95% USL 91.57 99% Percentile (z) 139.5
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level

Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
65.4
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
65.4
90% Percentile
64.85
90% Chebyshev UPL
115.6
95% Percentile
65.12
95% Chebyshev UPL
146
99% Percentile
65.34
95% USL
65.4
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
cobalt
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
3.9
First Quartile
6.338
Second Largest
7.63
Median
7.39
Maximum
14.1
Third Quartile
9.246
Mean
8.194
SD
4.269
Coefficient of Variation
0.521
Skewness
1.072
Mean of logged Data
2.001
SD of logged Data
0.525
Critical Values for Background Threshold Values (BTUs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.919
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.303
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
30.15
90% Percentile (z)
13.66
95% UPL (t)
19.43
95% Percentile (z)
15.22
95% USL
14.44
99% Percentile (z)
18.12
Gamma GOF Test
A-D Test Statistic
0.29
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.659
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.254
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.396
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level

Gamma Statistics
k hat (MLE)
5.069
k star (bias corrected MLE)
1.434
Theta hat (MLE)
1.616
Theta star (bias corrected MLE)
5.714
nu hat (MLE)
40.55
nu star (bias corrected)
11.47
MLE Mean (bias corrected)
8.194
MLE Sd (bias corrected)
6.843
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
23.87
90% Percentile
17.26
95% Hawkins Wixley (HW) Approx. Gamma UPL
24.89
95% Percentile
21.67
95% WH Approx. Gamma UTL with 95% Coverage
52.57
99% Percentile
31.65
95% HW Approx. Gamma UTL with 95% Coverage
59.85
95% WH USL
15.18
95% HW USL 15.33
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.965
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.227
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
110.3
90% Percentile (z)
14.51
95% UPL (t)
29.47
95% Percentile (z)
17.56
95% USL
15.95
99% Percentile (z)
25.11
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
14.1
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
14.1
90% Percentile
12.16
90% Chebyshev UPL
22.51
95% Percentile
13.13
95% Chebyshev UPL
29
99% Percentile
13.9
95% USL
14.1
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
copper
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
4.2
First Quartile
7.365
Second Largest
8.55
Median
8.485

Maximum
10.3
Third Quartile
8.986
Mean
7.866
SD
2.589
Coefficient of Variation
0.329
Skewness
-1.323
Mean of logged Data
2.011
SD of logged Data
0.395
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.881
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.335
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
21.19
90% Percentile (z)
11.18
95% UPL (t)
14.68
95% Percentile (z)
12.13
95% USL
11.65
99% Percentile (z)
13.89
Gamma GOF Test
A-D Test Statistic
0.517
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.657
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.376
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.395
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
9.824
k star (bias corrected MLE)
2.623
Theta hat (MLE)
0.801
Theta star (bias corrected MLE)
2.999
nu hat (MLE)
78.59
nu star (bias corrected)
20.98
MLE Mean (bias corrected)
7.866
MLE Sd (bias corrected)
4.857
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
17.78
90% Percentile
14.38
95% Hawkins Wixley (HW) Approx. Gamma UPL
18.42
95% Percentile
17.17
95% WH Approx. Gamma UTL with 95% Coverage
33.5
99% Percentile
23.27
95% HW Approx. Gamma UTL with 95% Coverage
36.97
95% WH USL
12.56
95% HW USL 12.72
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.82
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.369
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
56.85
90% Percentile (z)
12.38
95% UPL (t)
21.09
95% Percentile (z)
14.29

95% USL
1 13.3
1 99% Percentile (z)
18.7
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
10.3
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
10.3
90% Percentile
9.772
90% Chebyshev UPL
16.55
95% Percentile
10.03
95% Chebyshev UPL
20.49
99% Percentile
10.24
95% USL
10.3
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
lead
General Statistics
Total Number of Observations
2
Number of Distinct Observations
2
Number of Missing Observations
2
Minimum
4
First Quartile
4.725
Second Largest
4
Median
5.45
Maximum
6.9
Third Quartile
6.175
Mean
5.45
SD
2.051
Coefficient of Variation
0.376
Skewness
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable lead was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
manganese
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
180
First Quartile
277.5
Second Largest
449
Median
379.5
Maximum
579
Third Quartile
481.5
Mean
379.5
SD
172.5
Coefficient of Variation
0.455
Skewness
0
Mean of logged Data
5.849
SD of logged Data
0.507

Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.992
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.156
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
1267
90% Percentile (z)
600.6
95% UPL (t)
833.4
95% Percentile (z)
663.2
95% USL
631.8
99% Percentile (z)
780.8
Gamma GOF Test
A-D Test Statistic
0.22
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.659
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.21
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.396
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
5.755
k star (bias corrected MLE)
1.605
Theta hat (MLE)
65.94
Theta star (bias corrected MLE)
236.4
nu hat (MLE)
46.04
nu star (bias corrected)
12.84
MLE Mean (bias corrected)
379.5
MLE Sd (bias corrected)
299.5
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
1049
90% Percentile
777.9
95% Hawkins Wixley (HW) Approx. Gamma UPL
1099
95% Percentile
966.5
95% WH Approx. Gamma UTL with 95% Coverage
2240
99% Percentile
1391
95% HW Approx. Gamma UTL with 95% Coverage
2554
95% WH USL
682.1
95% HW USL 691.8
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.969
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.194
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
4717
90% Percentile (z)
664.9
95% UPL (t)
1318
95% Percentile (z)
799.4
95% USL
728.8
99% Percentile (z)
1130
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level

Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
579
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
579
90% Percentile
540
90% Chebyshev UPL
958.1
95% Percentile
559.5
95% Chebyshev UPL
1220
99% Percentile
575.1
95% USL
579
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
mercury
General Statistics
Total Number of Observations
4
Number of Missing Observations
0
Number of Distinct Observations
4
Number of Detects
2
Number of Non -Detects
2
Number of Distinct Detects
2
Number of Distinct Non -Detects
2
Minimum Detect
0.0052
Minimum Non -Detect
0.0255
Maximum Detect
0.0078
Maximum Non -Detect
0.026
Variance Detected
3.3800E-6
Percent Non -Detects
50%
Mean Detected
0.0065
SD Detected
0.00184
Mean of Detected Logged Data
-5.056
SD of Detected Logged Data
0.287
Warning: Data set has only 2 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Not Enough Data to Perform GOF Test
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.0065
KM SD
0.0013
95% UTL95% Coverage
0.0132
95% KM UPL (t)
0.00992
90% KM Percentile (z)
0.00817
95% KM Percentile (z)
0.00864
99% KM Percentile (z)
0.00952
95% KM USL
0.0084
DL/2 Substitution Background Statistics Assuming Normal Distribution
Mean
0.00969
SD
0.00383
95% UTL95% Coverage
0.0294
95% UPL (t)
0.0198
90% Percentile (z)
0.0146
95% Percentile (z)
0.016

99% Percentile (z)
0.0186
1 95% USL
1 0.0153
DL/2 is not a recommended method. DL/2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
24.66
k star (bias corrected MLE)
N/A
Theta hat (MLE)
2.6356E-4
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
98.65
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (2kstar) N/A
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.0065
SD (KM)
0.0013
Variance (KM)
1.6900E-6
SE of Mean (KM)
0.0013
k hat (KM)
25
k star (KM)
6.417
nu hat (KM)
200
nu star (KM)
51.33
theta hat (KM)
2.6000E-4
theta star (KM)
0.00101
80% gamma percentile (KM)
0.0085
90% gamma percentile (KM)
0.00993
95% gamma percentile (KM)
0.0112
99% gamma percentile (KM)
0.0139
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.0157
0.0162
95% Approx. Gamma UPL
0.0105
0.0106
95% KM Gamma Percentile
0.00879
0.00882
95% Gamma USL
0.0085
0.00852
Lognormal GOF Test on Detected Observations Only
Not Enough Data to Perform GOF Test
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.00643
Mean in Log Scale
-5.056
SD in Original Scale
0.00106
SD in Log Scale
0.166
95% UTL95% Coverage
0.0149
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
0.00984
90% Percentile (z)
0.00787
95% Percentile (z)
0.00836
99% Percentile (z)
0.00936
95% USL
0.00811
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-5.056
95% KM UTL (Lognormal)95% Coverage
0.0181
KM SD of Logged Data
0.203
95% KM UPL (Lognormal)
0.0109
95% KM Percentile Lognormal (z)
0.00889
95% KM USL (Lognormal)
0.00857
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
0.00969
Mean in Log Scale
-4.704
SD in Original Scale
0.00383
SD in Log Scale
0.439
95% UTL95% Coverage
0.0866
95% UPL (t)
0.0287
90% Percentile (z)
0.0159
95% Percentile (z)
0.0186
99% Percentile (z)
1 0.0251
95% USL
0.0172

DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
0.026
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
0.026
95% USL
0.026
95% KM Chebyshev UPL
0.0128
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
nickel
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
3.8
First Quartile
5.9
Second Largest
7.1
Median
6.85
Maximum
9.54
Third Quartile
7.71
Mean
6.76
SD
2.355
Coefficient of Variation
0.348
Skewness
-0.225
Mean of logged Data
1.859
SD of logged Data
0.384
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.976
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.223
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
18.87
90% Percentile (z)
9.777
95% UPL (t)
12.96
95% Percentile (z)
10.63
95% USL
10.2
99% Percentile (z)
12.24
Gamma GOF Test
A-D Test Statistic
0.289
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.657
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.263
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.395
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level

Gamma Statistics
k hat (MLE)
9.852
k star (bias corrected MLE)
2.63
Theta hat (MLE)
0.686
Theta star (bias corrected MLE)
2.571
nu hat (MLE)
78.82
nu star (bias corrected)
21.04
MLE Mean (bias corrected)
6.76
MLE Sd (bias corrected)
4.169
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
15.26
90% Percentile
12.35
95% Hawkins Wixley (HW) Approx. Gamma UPL
15.73
95% Percentile
14.74
95% WH Approx. Gamma UTL with 95% Coverage
28.74
99% Percentile
19.97
95% HW Approx. Gamma UTL with 95% Coverage
31.44
95% WH USL
10.78
95% HW USL 10.88
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.939
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.279
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
46.32
90% Percentile (z)
10.5
95% UPL (t)
17.64
95% Percentile (z)
12.08
95% USL
11.26
99% Percentile (z)
15.69
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
9.54
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
9.54
90% Percentile
8.808
90% Chebyshev UPL
14.66
95% Percentile
9.174
95% Chebyshev UPL
18.23
99% Percentile
9.467
95% USL
9.54
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
selenium
General Statistics
Total Number of Observations
4
Number of Missing Observations
0
Number of Distinct Observations
3
Number of Detects
2
Number of Non -Detects
2

Number of Distinct Detects
2
Number of Distinct Non -Detects
1
Minimum Detect
0.272
Minimum Non -Detect
0.64
Maximum Detect
0.409
Maximum Non -Detect
0.64
Variance Detected
0.00945
Percent Non -Detects
50%
Mean Detected
0.34
SD Detected
0.0972
Mean of Detected Logged Data
-1.099
SD of Detected Logged Data
0.29
Warning: Data set has only 2 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Not Enough Data to Perform GOF Test
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.34
KM SD
0.0688
95% UTL95% Coverage
0.694
95% KM UPL (t)
0.521
90% KM Percentile (z)
0.428
95% KM Percentile (z)
0.453
99% KM Percentile (z)
0.5
95% KM USL
0.441
DL/2 Substitution Background Statistics Assuming Normal Distribution
Mean
0.33
SD
0.0573
95% UTL95% Coverage
0.625
95% UPL (t)
0.481
90% Percentile (z)
0.404
95% Percentile (z)
0.424
99% Percentile (z)
0.464
95% USL
0.414
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
24.16
k star (bias corrected MLE)
N/A
Theta hat (MLE)
0.0141
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
96.62
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (2kstar) N/A
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.34
SD (KM)
0.0688
Variance (KM)
0.00473
SE of Mean (KM)
0.0688
k hat (KM)
24.49
k star (KM)
6.29
nu hat (KM)
195.9
nu star (KM)
50.32
theta hat (KM)
0.0139
theta star (KM)
0.0541
80% gamma percentile (KM)
0.446
90% gamma percentile (KM)
0.522
95% gamma percentile (KM)
0.59
99% gamma percentile (KM)
0.732
The following statistics are computed using gamma distribution and KM estimates

Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.827
0.853
95% Approx. Gamma UPL
0.551
0.555
95% KM Gamma Percentile
0.462
0.463
95% Gamma USL
0.446
0.447
Lognormal GOF Test on Detected Observations Only
Not Enough Data to Perform GOF Test
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.34
Mean in Log Scale
-1.099
SD in Original Scale
0.0794
SD in Log Scale
0.237
95% UTL95% Coverage
1.125
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
0.621
90% Percentile (z)
0.451
95% Percentile (z)
0.492
99% Percentile (z)
0.578
95% USL
0.471
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-1.099
95% KM UTL (Lognormal)95% Coverage
0.956
KM SD of Logged Data
0.205
95% KM UPL (Lognormal)
0.571
95% KM Percentile Lognormal (z)
0.467
95% KM USL (Lognormal)
0.45
Background DU2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
0.33
Mean in Log Scale
-1.119
SD in Original Scale
0.0573
SD in Log Scale
0.169
95% UTL95% Coverage
0.779
95% UPL (t)
0.509
90% Percentile (z)
0.405
95% Percentile (z)
0.431
99% Percentile (z)
0.484
95% USL
0.418
DU2 is not a Recommended Method. DU2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
0.64
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
0.64
95% USL
0.64
95% KM Chebyshev UPL
0.675
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
strontium
General Statistics
Total Number of Observations
4
Number of Distinct Observations
4
Minimum
6.9
First Quartile
8.025
Second Largest
11.5
Median
9.95

Maximum
12.85
Third Quartile
11.84
Mean
9.913
SD
2.739
Coefficient of Variation
0.276
Skewness
-0.0471
Mean of logged Data
2.264
SD of logged Data
0.285
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.944
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.219
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
24
90% Percentile (z)
13.42
95% UPL (t)
17.12
95% Percentile (z)
14.42
95% USL
13.92
99% Percentile (z)
16.29
Gamma GOF Test
A-D Test Statistic
0.296
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.657
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.26
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.394
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
16.87
k star (bias corrected MLE)
4.384
Theta hat (MLE)
0.588
Theta star (bias corrected MLE)
2.261
nu hat (MLE)
134.9
nu star (bias corrected)
35.07
MLE Mean (bias corrected)
9.913
MLE Sd (bias corrected)
4.734
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
18.91
90% Percentile
16.26
95% Hawkins Wixley (HW) Approx. Gamma UPL
19.23
95% Percentile
18.76
95% WH Approx. Gamma UTL with 95% Coverage
31.87
99% Percentile
24.09
95% HW Approx. Gamma UTL with 95% Coverage
33.66
95% WH USL
14.33
95% HW USL 14.39
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.942
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.234
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
41.78
90% Percentile (z)
13.87
95% UPL (t)
20.39
95% Percentile (z)
15.39

95% USL
1 14.61
1 99% Percentile (z)
18.69
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
12.85
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
12.85
90% Percentile
12.45
90% Chebyshev UPL
19.1
95% Percentile
12.65
95% Chebyshev UPL
23.26
99% Percentile
12.81
95% USL
12.85
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
thallium
General Statistics
Total Number of Observations
2 Number of Missing Observations
2
Number of Distinct Observations
1
Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
0.64
Maximum Detect
N/A
Maximum Non -Detect
0.64
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable thallium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
vanadium
General Statistics
Total Number of Observations
2
Number of Distinct Observations
2
Number of Missing Observations
2
Minimum
19
First Quartile
23.25
Second Largest
19
Median
27.5
Maximum
36
Third Quartile
31.75

Mean
27.5
1 SD
12.02
Coefficient of Variation
0.437
1 Skewness
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable vanadium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
zinc
General Statistics
Total Number of Observations
2
Number of Distinct Observations
2
Number of Missing Observations
2
Minimum
19
First Quartile
22.38
Second Largest
19
Median
25.75
Maximum
32.5
Third Quartile
29.13
Mean
25.75
SD
9.546
Coefficient of Variation
0.371
Skewness
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable zinc was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.

Background Statistics for Data Sets with Non -Detects
User Selected Options
Date/Time of Computation
ProUCL 5.18/20/2021 9:47:02 AM
From File
ProUCL Background Inputs_a.xls
Full Precision
OFF
Confidence Coefficient
95%
Coverage
95%
Different or Future K Observations
1
Number of Bootstrap Operations
2000
aluminum
General Statistics
Total Number of Observations
0
Number of Distinct Observations
0
Number of Missing Observations
5
Minimum
N/A
First Quartile
N/A
Second Largest
N/A
Median
N/A
Maximum
N/A
Third Quartile
N/A
Mean
N/A
SD
N/A
Coefficient of Variation
N/A
Skewness
N/A
Warning: This data set only has 0 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable aluminum was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
antimony
General Statistics
Total Number of Observations
2
Number of Missing Observations
3
Number of Distinct Observations
1
Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
5
Maximum Detect
N/A
Maximum Non -Detect
5
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable antimony was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.

arsenic
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
3
Number of Detects
2
Number of Non -Detects
2
Number of Distinct Detects
2
Number of Distinct Non -Detects
1
Minimum Detect
0.42
Minimum Non -Detect
10
Maximum Detect
0.44
Maximum Non -Detect
10
Variance Detected
2.0000E-4
Percent Non -Detects
50%
Mean Detected
0.43
SD Detected
0.0141
Mean of Detected Logged Data
-0.844
SD of Detected Logged Data
0.0329
Warning: Data set has only 2 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Not Enough Data to Perform GOF Test
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.43
KM SD
0.01
95% UTL95% Coverage
0.481
95% KM UPL (t)
0.456
90% KM Percentile (z)
0.443
95% KM Percentile (z)
0.446
99% KM Percentile (z)
0.453
95% KM USL
0.445
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
2.715
SD
2.639
95% UTL95% Coverage
16.29
95% UPL (t)
9.657
90% Percentile (z)
6.096
95% Percentile (z)
7.055
99% Percentile (z)
8.853
95% USL
6.574
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
1849
k star (bias corrected MLE)
N/A
Theta hat (MLE)
2.3260E-4
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
7395
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (2kstar) N/A
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.43
SD (KM)
0.01
Variance (KM)
1.0000E-4
SE of Mean (KM)
0.01
k hat (KM)
1849
k star (KM) 462.4

nu hat (KM)
14792
nu star (KM)
3699
theta hat (KM)
2.3256E-4
theta star (KM)
9.2990E-4
80% gamma percentile (KM)
0.447
90% gamma percentile (KM)
0.456
95% gamma percentile (KM)
0.463
99% gamma percentile (KM)
0.478
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.483
0.484
95% Approx. Gamma UPL
0.457
0.457
95% KM Gamma Percentile
0.447
0.447
95% Gamma USL
0.445
0.445
Lognormal GOF Test on Detected Observations Only
Not Enough Data to Perform GOF Test
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.43
Mean in Log Scale
-0.844
SD in Original Scale
0.0115
SD in Log Scale
0.0269
95% UTL95% Coverage
0.494
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
0.461
90% Percentile (z)
0.445
95% Percentile (z)
0.449
99% Percentile (z)
0.458
95% USL
0.447
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-0.844
95% KM UTL (Lognormal)95% Coverage
0.485
KM SD of Logged Data
0.0233
95% KM UPL (Lognormal)
0.457
95% KM Percentile Lognormal (z)
0.447
95% KM USL (Lognormal)
0.445
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
2.715
Mean in Log Scale
0.383
SD in Original Scale
2.639
SD in Log Scale
1.417
95% UTL95% Coverage
2144
95% UPL (t)
60.96
90% Percentile (z)
9.009
95% Percentile (z)
15.07
99% Percentile (z)
39.59
95% USL
11.64
DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
10
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
10
95% USL
10
95% KM Chebyshev UPL
0.479
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.

barium
General Statistics
Total Number of Observations
5
Number of Distinct Observations
4
Minimum
23.1
First Quartile
23.2
Second Largest
27
Median
24
Maximum
27
Third Quartile
27
Mean
24.86
SD
1.984
Coefficient of Variation
0.0798
Skewness
0.477
Mean of logged Data
3.211
SD of logged Data
0.0791
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 4.203 d2max (for USL) 1.671
Normal GOF Test
Shapiro Wilk Test Statistic
0.782
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.762
Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.268
Lilliefors GOF Test
5% Lilliefors Critical Value
0.343
Data appear Normal at 5% Significance Level
Data appear Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
33.2
90% Percentile (z)
27.4
95% UPL (t)
29.49
95% Percentile (z)
28.12
95% USL
28.18
99% Percentile (z)
29.48
Gamma GOF Test
A-D Test Statistic
0.647
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.678
Detected data appear Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.286
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.357
Detected data appear Gamma Distributed at 5% Significance Level
Detected data appear Gamma Distributed at 5% Significance Level
Gamma Statistics
k hat (MLE)
198.8
k star (bias corrected MLE)
79.64
Theta hat (MLE)
0.125
Theta star (bias corrected MLE)
0.312
nu hat (MLE)
1988
nu star (bias corrected)
796.4
MLE Mean (bias corrected)
24.86
MLE Sd (bias corrected)
2.786
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
29.71
90% Percentile
28.49
95% Hawkins Wixley (HW) Approx. Gamma UPL
29.74
95% Percentile
29.61
95% WH Approx. Gamma UTL with 95% Coverage
34.05
99% Percentile
31.8
95% HW Approx. Gamma UTL with 95% Coverage
34.17
95% WH USL
28.26
95% HW USL 28.27
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.787
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.762
Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.26
Lilliefors Lognormal GOF Test

5% Lilliefors Critical Value
0.343
1 Data appear Lognormal at 5% Significance Level
Data appear Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
34.57
90% Percentile (z)
27.44
95% UPL (t)
29.83
95% Percentile (z)
28.24
95% USL
28.3
99% Percentile (z)
29.81
Nonparametric Distribution Free Background Statistics
Data appear Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
5
95% UTL with 95% Coverage
27
Approx, f used to compute achieved CC
0.263
Approximate Actual Confidence Coefficient achieved by UTL
0.226
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
27
95% BCA Bootstrap UTL with 95% Coverage
27
95% UPL
27
90% Percentile
27
90% Chebyshev UPL
31.38
95% Percentile
27
95% Chebyshev UPL
34.34
99% Percentile
27
95% USL
27
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
beryllium
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
2
Number of Detects
0
Number of Non -Detects
4
Number of Distinct Detects
0
Number of Distinct Non -Detects
2
Minimum Detect
N/A
Minimum Non -Detect
0.1
Maximum Detect
N/A
Maximum Non -Detect
2
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: All observations are Non -Detects (NDs), therefore all statistics and estimates should also be NDs!
Specifically, sample mean, UCLs, UPLs, and other statistics are also NDs lying below the largest detection limit!
The Project Team may decide to use alternative site specific values to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable beryllium was not processed!
cadmium
General Statistics

Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
2
Number of Detects
0
Number of Non -Detects
4
Number of Distinct Detects
0
Number of Distinct Non -Detects
2
Minimum Detect
N/A
Minimum Non -Detect
0.08
Maximum Detect
N/A
Maximum Non -Detect
1
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: All observations are Non -Detects (NDs), therefore all statistics and estimates should also be NDs!
Specifically, sample mean, UCLs, UPLs, and other statistics are also NDs lying below the largest detection limit!
The Project Team may decide to use alternative site specific values to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable cadmium was not processed!
calcium
General Statistics
Total Number of Observations
0
Number of Distinct Observations
0
Number of Missing Observations
5
Minimum
N/A
First Quartile
N/A
Second Largest
N/A
Median
N/A
Maximum
N/A
Third Quartile
N/A
Mean
N/A
SD
N/A
Coefficient of Variation
N/A
Skewness
N/A
Warning: This data set only has 0 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable calcium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
hexavalent chromium
General Statistics
Total Number of Observations
2
Number of Missing Observations
3
Number of Distinct Observations
1
Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
0.74
Maximum Detect
N/A
Maximum Non -Detect
0.74
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!

Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable hexavalent chromium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
trivalent chromium
General Statistics
Total Number of Observations
0
Number of Distinct Observations
0
Number of Missing Observations
5
Minimum
N/A
First Quartile
N/A
Second Largest
N/A
Median
N/A
Maximum
N/A
Third Quartile
N/A
Mean
N/A
SD
N/A
Coefficient of Variation
N/A
Skewness
N/A
Warning: This data set only has 0 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable trivalent chromium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
total chromium
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
3
Number of Detects
2
Number of Non -Detects
2
Number of Distinct Detects
2
Number of Distinct Non -Detects
1
Minimum Detect
0.45
Minimum Non -Detect
5
Maximum Detect
0.53
Maximum Non -Detect
5
Variance Detected
0.0032
Percent Non -Detects
50%
Mean Detected
0.49
SD Detected
0.0566
Mean of Detected Logged Data
-0.717
SD of Detected Logged Data
0.116
Warning: Data set has only 2 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL)
1.462
Normal GOF Test on Detects Only
Not Enough Data to Perform GOF Test
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution

KM Mean
0.49
KM SD
0.04
95% UTL95% Coverage
0.696
95% KM UPL (t)
0.595
90% KM Percentile (z)
0.541
95% KM Percentile (z)
0.556
99% KM Percentile (z)
0.583
95% KM USL
0.548
DL/2 Substitution Background Statistics Assuming Normal Distribution
Mean
1.495
SD
1.161
95% UTL95% Coverage
7.467
95% UPL (t)
4.55
90% Percentile (z)
2.983
95% Percentile (z)
3.405
99% Percentile (z)
4.196
95% USL
3.193
DL/2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
149.7
k star (bias corrected MLE)
N/A
Theta hat (MLE)
0.00327
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
598.9
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (21kstar) N/A
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.49
SD (KM)
0.04
Variance (KM)
0.0016
SE of Mean (KM)
0.04
k hat (KM)
150.1
k star (KM)
37.68
nu hat (KM)
1201
nu star (KM)
301.5
theta hat (KM)
0.00327
theta star (KM)
0.013
80% gamma percentile (KM)
0.556
90% gamma percentile (KM)
0.595
95% gamma percentile (KM)
0.628
99% gamma percentile (KM)
0.695
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty, (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.725
0.729
95% Approx. Gamma UPL
0.602
0.603
95% KM Gamma Percentile
0.558
0.558
95% Gamma USL
0.55
0.55
Lognormal GOF Test on Detected Observations Only
Not Enough Data to Perform GOF Test
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.49
Mean in Log Scale
-0.717
SD in Original Scale
0.0462
SD in Log Scale
0.0945
95% UTL95% Coverage
0.794
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
0.626
90% Percentile (z)
0.551
95% Percentile (z)
0.57
99% Percentile (z)
0.608
95% USL
0.561
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-0.717
95% KM UTL (Lognormal)95% Coverage
0.744

KM SD of Logged Data
0.0818
95% KM UPL (Lognormal)
0.606
95% KM Percentile Lognormal (z)
0.559
95% KM USL (Lognormal)
0.55
Background DU2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
1.495
Mean in Log Scale
0.0998
SD in Original Scale
1.161
SD in Log Scale
0.945
95% UTL95% Coverage
142.8
95% UPL (t)
13.29
90% Percentile (z)
3.71
95% Percentile (z)
5.23
99% Percentile (z)
9.96
95% USL
4.402
DU2 is not a Recommended Method. DU2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
5
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
5
95% USL
5
95% KM Chebyshev UPL
0.685
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
cobalt
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
2
Number of Detects
2
Number of Non -Detects
2
Number of Distinct Detects
1
Number of Distinct Non -Detects
1
Minimum Detect
0.16
Minimum Non -Detect
5
Maximum Detect
0.16
Maximum Non -Detect
5
Variance Detected
0
Percent Non -Detects
50%
Mean Detected
0.16
SD Detected
0
Mean of Detected Logged Data
-1.833
SD of Detected Logged Data
0
Warning: Only one distinct data value was detected! ProUCL (or any other software) should not be used on such a data set!
It is suggested to use alternative site specific values determined by the Project Team to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable cobalt was not processed!
copper
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
3

Number of Detects
2
Number of Non -Detects
2
Number of Distinct Detects
2
Number of Distinct Non -Detects
1
Minimum Detect
1.1
Minimum Non -Detect
10
Maximum Detect
1.2
Maximum Non -Detect
10
Variance Detected
0.005
Percent Non -Detects
50%
Mean Detected
1.15
SD Detected
0.0707
Mean of Detected Logged Data
0.139
SD of Detected Logged Data
0.0615
Warning: Data set has only 2 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.
Critical Values for Background Threshold Values (BTUs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Not Enough Data to Perform GOF Test
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
1.15
KM SD
0.05
95% UTL95% Coverage
1.407
95% KM UPL (t)
1.282
90% KM Percentile (z)
1.214
95% KM Percentile (z)
1.232
99% KM Percentile (z)
1.266
95% KM USL
1.223
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
3.075
SD
2.223
95% UTL95% Coverage
14.51
95% UPL (t)
8.924
90% Percentile (z)
5.924
95% Percentile (z)
6.732
99% Percentile (z)
8.247
95% USL
6.326
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
528.7
k star (bias corrected MLE)
N/A
Theta hat (MLE)
0.00218
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
2115
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (2kstar) N/A
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
1.15
SD (KM)
0.05
Variance (KM)
0.0025
SE of Mean (KM)
0.05
k hat (KM)
529
k star (KM)
132.4
nu hat (KM)
4232
nu star (KM)
1059
theta hat (KM)
0.00217
theta star (KM)
0.00868
80% gamma percentile (KM)
1.233
90% gamma percentile (KM)
1.28
95% gamma percentile (KM)
1.319
99% gamma percentile (KM)
1.395

The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
1.426
1.429
95% Approx. Gamma UPL
1.286
1.286
95% KM Gamma Percentile
1.233
1.234
95% Gamma USL
1.224
1.224
Lognormal GOF Test on Detected Observations Only
Not Enough Data to Perform GOF Test
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
1.15
Mean in Log Scale
0.139
SD in Original Scale
0.0577
SD in Log Scale
0.0502
95% UTL95% Coverage
1.488
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
1.311
90% Percentile (z)
1.225
95% Percentile (z)
1.248
99% Percentile (z)
1.291
95% USL
1.237
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
0.139
95% KM UTL (Lognormal)95% Coverage
1.437
KM SD of Logged Data
0.0435
95% KM UPL (Lognormal)
1.288
95% KM Percentile Lognormal (z)
1.234
95% KM USL (Lognormal)
1.224
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
3.075
Mean in Log Scale
0.874
SD in Original Scale
2.223
SD in Log Scale
0.85
95% UTL95% Coverage
189.7
95% UPL (t)
22.42
90% Percentile (z)
7.122
95% Percentile (z)
9.698
99% Percentile (z)
17.31
95% USL
8.306
DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
10
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
10
95% USL
10
95% KM Chebyshev UPL
1.394
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
iron
General Statistics
Total Number of Observations
2
Number of Missing Observations
3
Number of Distinct Observations
1

Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
0.2
Maximum Detect
N/A
Maximum Non -Detect
0.2
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable iron was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
lead
General Statistics
Total Number of Observations
2
Number of Missing Observations
3
Number of Distinct Observations
1
Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
5
Maximum Detect
N/A
Maximum Non -Detect
5
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable lead was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
magnesium
General Statistics
Total Number of Observations
0
Number of Distinct Observations
0
Number of Missing Observations
5
Minimum
N/A
First Quartile
N/A
Second Largest
N/A
Median
N/A
Maximum
N/A
Third Quartile
N/A
Mean
N/A
SD
N/A
Coefficient of Variation
N/A
Skewness
N/A
Warning: This data set only has 0 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!

The data set for variable magnesium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
manganese
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
4
Number of Detects
3
Number of Non -Detects
1
Number of Distinct Detects
3
Number of Distinct Non -Detects
1
Minimum Detect
11
Minimum Non -Detect
10
Maximum Detect
22.2
Maximum Non -Detect
10
Variance Detected
38.41
Percent Non -Detects
25%
Mean Detected
18.13
SD Detected
6.198
Mean of Detected Logged Data
2.851
SD of Detected Logged Data
0.393
Warning: Data set has only 3 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 1 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Shapiro Wilk Test Statistic
0.816
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.767
Detected Data appear Normal at 5% Significance Level
Lilliefors Test Statistic
0.356
Lilliefors GOF Test
5% Lilliefors Critical Value
0.425
Detected Data appear Normal at 5% Significance Level
Detected Data appear Normal at 5% Significance Level
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
16.1
KM SD
5.622
95% UTL95% Coverage
45.02
95% KM UPL (t)
30.89
90% KM Percentile (z)
23.31
95% KM Percentile (z)
25.35
99% KM Percentile (z)
29.18
95% KM USL
24.32
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
14.85
SD
8.29
95% UTL95% Coverage
57.5
95% UPL (t)
36.66
90% Percentile (z)
25.47
95% Percentile (z)
28.49
99% Percentile (z)
34.14
95% USL
26.97
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only

k hat (MLE)
10.78
k star (bias corrected MLE)
N/A
Theta hat (MLE)
1.682
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
64.69
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (21kstar) N/A
Gamma ROS Statistics using Imputed Non -Detects
GROS may not be used when data set has > 50% NDs with many tied observations at multiple DLs
GROS may not be used when kstar of detects is small such as <1.0, especially when the sample size is small (e.g., <15-20)
For such situations, GROS method may yield incorrect values of UCLs and BTVs
This is especially true when the sample size is small.
For gamma distributed detected data, BTVs and UCLs may be computed using gamma distribution on KM estimates
Minimum
4.816
Mean
14.8
Maximum
22.2
Median
16.1
SD
8.363
CV
0.565
k hat (MLE)
3.208
k star (bias corrected MLE)
0.969
Theta hat (MLE)
4.615
Theta star (bias corrected MLE)
15.28
nu hat (MLE)
25.66
nu star (bias corrected)
7.748
MLE Mean (bias corrected)
14.8
MLE Sd (bias corrected)
15.04
95% Percentile of Chisquare (2kstar)
5.869
90% Percentile
34.36
95% Percentile
44.85
99% Percentile
69.28
The following statistics are computed using Gamma ROS Statistics on Imputed Data
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
131.9
162.7
95% Approx. Gamma UPL
53.28
57.8
95% Gamma USL
31.12
32.01
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
16.1
SD (KM)
5.622
Variance (KM)
31.61
SE of Mean (KM)
3.443
k hat (KM)
8.2
k star (KM)
2.217
nu hat (KM)
65.6
nu star (KM)
17.73
theta hat (KM)
1.963
theta star (KM)
7.263
80% gamma percentile (KM)
23.81
90% gamma percentile (KM)
30.57
95% gamma percentile (KM)
36.98
99% gamma percentile (KM)
51.11
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
65.9
71.26
95% Approx. Gamma UPL
35.35
36.2
95% KM Gamma Percentile
26.59
26.8
95% Gamma USL
25.15
25.28
Lognormal GOF Test on Detected Observations Only
Shapiro Wilk Test Statistic
0.799
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.767
Detected Data appear Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.364
Lilliefors GOF Test
5% Lilliefors Critical Value
0.425
Detected Data appear Lognormal at 5% Significance Level
Detected Data appear Lognormal at 5% Significance Level
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects

Mean in Original Scale
15.22
Mean in Log Scale
2.606
SD in Original Scale
7.712
SD in Log Scale
0.586
95% UTL95% Coverage
275.3
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
63.21
90% Percentile (z)
28.68
95% Percentile (z)
35.48
99% Percentile (z)
52.88
95% USL
31.88
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
2.714
95% KM UTL (Lognormal)95% Coverage
98.78
KM SD of Logged Data
0.365
95% KM UPL (Lognormal)
39.44
95% KM Percentile Lognormal (z)
27.51
95% KM USL (Lognormal)
25.74
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
14.85
Mean in Log Scale
2.54
SD in Original Scale
8.29
SD in Log Scale
0.699
95% UTL95% Coverage
461.2
95% UPL (t)
79.71
90% Percentile (z)
31.05
95% Percentile (z)
40.02
99% Percentile (z)
64.42
95% USL
35.23
DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data appear to follow a Discernible Distribution at 5% Significance Level
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
22.2
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
22.2
95% USL
22.2
95% KM Chebyshev UPL
43.5
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
mercury
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
1
Number of Detects
0
Number of Non -Detects
4
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
0.2
Maximum Detect
N/A
Maximum Non -Detect
0.2
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: All observations are Non -Detects (NDs), therefore all statistics and estimates should also be NDs!
Specifically, sample mean, UCLs, UPLs, and other statistics are also NDs lying below the largest detection limit!

The Project Team may decide to use alternative site specific values to estimate environmental parameters (e.g., EPC, BTV).
The data set for variable mercury was not processed!
nickel
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
3
Number of Detects
2
Number of Non -Detects
2
Number of Distinct Detects
2
Number of Distinct Non -Detects
1
Minimum Detect
0.29
Minimum Non -Detect
10
Maximum Detect
0.33
Maximum Non -Detect
10
Variance Detected
8.0000E-4
Percent Non -Detects
50%
Mean Detected
0.31
SD Detected
0.0283
Mean of Detected Logged Data
-1.173
SD of Detected Logged Data
0.0914
Warning: Data set has only 2 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.
Critical Values for Background Threshold Values (BTUs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Not Enough Data to Perform GOF Test
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.31
KM SD
0.02
95% UTL95% Coverage
0.413
95% KM UPL (t)
0.363
90% KM Percentile (z)
0.336
95% KM Percentile (z)
0.343
99% KM Percentile (z)
0.357
95% KM USL
0.339
DU2 Substitution Background Statistics Assuming Normal Distribution
Mean
2.655
SD
2.708
95% UTL95% Coverage
16.58
95% UPL (t)
9.78
90% Percentile (z)
6.125
95% Percentile (z)
7.109
99% Percentile (z)
8.954
95% USL
6.615
DU2 is not a recommended method. DU2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
239.9
k star (bias corrected MLE)
N/A
Theta hat (MLE)
0.00129
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
959.7
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (2kstar)
N/A

Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.31
SD (KM)
0.02
Variance (KM)
4.0000E-4
SE of Mean (KM)
0.02
k hat (KM)
240.3
k star (KM)
60.23
nu hat (KM)
1922
nu star (KM)
481.8
theta hat (KM)
0.00129
theta star (KM)
0.00515
80% gamma percentile (KM)
0.343
90% gamma percentile (KM)
0.362
95% gamma percentile (KM)
0.378
99% gamma percentile (KM)
0.41
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.424
0.426
95% Approx. Gamma UPL
0.365
0.366
95% KM Gamma Percentile
0.344
0.344
95% Gamma USL
0.34
0.34
Lognormal GOF Test on Detected Observations Only
Not Enough Data to Perform GOF Test
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.31
Mean in Log Scale
-1.173
SD in Original Scale
0.0231
SD in Log Scale
0.0746
95% UTL95% Coverage
0.454
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
0.376
90% Percentile (z)
0.34
95% Percentile (z)
0.35
99% Percentile (z)
0.368
95% USL
0.345
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-1.173
95% KM UTL (Lognormal)95% Coverage
0.431
KM SD of Logged Data
0.0646
95% KM UPL (Lognormal)
0.367
95% KM Percentile Lognormal (z)
0.344
95% KM USL (Lognormal)
0.34
Background DL/2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
2.655
Mean in Log Scale
0.218
SD in Original Scale
2.708
SD in Log Scale
1.607
95% UTL95% Coverage
4851
95% UPL (t)
85.42
90% Percentile (z)
9.758
95% Percentile (z)
17.5
99% Percentile (z)
52.33
95% USL
13.05
DL/2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
10
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
10
95% USL
10
95% KM Chebyshev UPL
0.407
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.

Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
potassium
General Statistics
Total Number of Observations
0
Number of Distinct Observations
0
Number of Missing Observations
5
Minimum
N/A
First Quartile
N/A
Second Largest
N/A
Median
N/A
Maximum
N/A
Third Quartile
N/A
Mean
N/A
SD
N/A
Coefficient of Variation
N/A
Skewness
N/A
Warning: This data set only has 0 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable potassium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
selenium
General Statistics
Total Number of Observations
4
Number of Missing Observations
1
Number of Distinct Observations
3
Number of Detects
2
Number of Non -Detects
2
Number of Distinct Detects
2
Number of Distinct Non -Detects
1
Minimum Detect
0.096
Minimum Non -Detect
20
Maximum Detect
0.11
Maximum Non -Detect
20
Variance Detected
9.8000E-5
Percent Non -Detects
50%
Mean Detected
0.103
SD Detected
0.0099
Mean of Detected Logged Data
-2.275
SD of Detected Logged Data
0.0963
Warning: Data set has only 2 Detected Values.
This is not enough to compute meaningful or reliable statistics and estimates.
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test on Detects Only
Not Enough Data to Perform GOF Test
Kaplan Meier (KM) Background Statistics Assuming Normal Distribution
KM Mean
0.103
KM SD
0.007
95% UTL95% Coverage
0.139
95% KM UPL (t)
0.121

90% KM Percentile (z)
0.112
95% KM Percentile (z)
0.115
99% KM Percentile (z)
0.119
95% KM USL
0.113
DL/2 Substitution Background Statistics Assuming Normal Distribution
Mean
5.052
SD
5.714
95% UTL95% Coverage
34.44
95% UPL (t)
20.09
90% Percentile (z)
12.37
95% Percentile (z)
14.45
99% Percentile (z)
18.34
95% USL
13.41
DL/2 is not a recommended method. DL/2 provided for comparisons and historical reasons
Gamma GOF Tests on Detected Observations Only
Not Enough Data to Perform GOF Test
Gamma Statistics on Detected Data Only
k hat (MLE)
216.2
k star (bias corrected MLE)
N/A
Theta hat (MLE)
4.7646E-4
Theta star (bias corrected MLE)
N/A
nu hat (MLE)
864.7
nu star (bias corrected)
N/A
MLE Mean (bias corrected)
N/A
MLE Sd (bias corrected)
N/A
95% Percentile of Chisquare (21kstar) N/A
Estimates of Gamma Parameters using KM Estimates
Mean (KM)
0.103
SD (KM)
0.007
Variance (KM)
4.9000E-5
SE of Mean (KM)
0.007
k hat (KM)
216.5
k star (KM)
54.29
nu hat (KM)
1732
nu star (KM)
434.4
theta hat (KM)
4.7573E-4
theta star (KM)
0.0019
80% gamma percentile (KM)
0.115
90% gamma percentile (KM)
0.121
95% gamma percentile (KM)
0.127
99% gamma percentile (KM)
0.138
The following statistics are computed using gamma distribution and KM estimates
Upper Limits using Wilson Hilferty (WH) and Hawkins Wixley (HW) Methods
WH
HW
WH
HW
95% Approx. Gamma UTL with 95% Coverage
0.143
0.144
95% Approx. Gamma UPL
0.122
0.123
95% KM Gamma Percentile
0.115
0.115
95% Gamma USL
0.113
0.113
Lognormal GOF Test on Detected Observations Only
Not Enough Data to Perform GOF Test
Background Lognormal ROS Statistics Assuming Lognormal Distribution Using Imputed Non -Detects
Mean in Original Scale
0.103
Mean in Log Scale
-2.275
SD in Original Scale
0.00808
SD in Log Scale
0.0786
95% UTL95% Coverage
0.154
95% BCA UTL95% Coverage
N/A
95% Bootstrap (%) UTL95% Coverage
N/A
95% UPL (t)
0.126
90% Percentile (z)
0.114
95% Percentile (z)
0.117
99% Percentile (z)
0.123
95% USL
0.115
Statistics using KM estimates on Logged Data and Assuming Lognormal Distribution
KM Mean of Logged Data
-2.275
95% KM UTL (Lognormal)95% Coverage
0.146
KM SD of Logged Data
0.0681
95% KM UPL (Lognormal)
0.123
95% KM Percentile Lognormal (z)
0.115
95% KM USL (Lognormal)
0.114

Background DU2 Statistics Assuming Lognormal Distribution
Mean in Original Scale
5.052
Mean in Log Scale
0.0136
SD in Original Scale
5.714
SD in Log Scale
2.644
95% UTL95% Coverage
816321
95% UPL (t)
1064
90% Percentile (z)
30.01
95% Percentile (z)
78.42
99% Percentile (z)
475.2
95% USL
48.42
DU2 is not a Recommended Method. DL/2 provided for comparisons and historical reasons.
Nonparametric Distribution Free Background Statistics
Data do not follow a Discernible Distribution (0.05)
Nonparametric Upper Limits for BTVs(no distinction made between detects and nondetects)
Order of Statistic, r
4
95% UTL with95% Coverage
20
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% UPL
20
95% USL
20
95% KM Chebyshev UPL
0.137
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data
represents a background data set and when many onsite observations need to be compared with the BTV.
strontium
General Statistics
Total Number of Observations
4
Number of Distinct Observations
3
Number of Missing Observations
1
Minimum
85.3
First Quartile
85.45
Second Largest
100
Median
92.75
Maximum
100
Third Quartile
100
Mean
92.7
SD
8.43
Coefficient of Variation
0.0909
Skewness
-4.875E-4
Mean of logged Data
4.526
SD of logged Data
0.0911
Critical Values for Background Threshold Values (BTVs)
Tolerance Factor K (For UTL) 5.144 d2max (for USL) 1.462
Normal GOF Test
Shapiro Wilk Test Statistic
0.737
Shapiro Wilk GOF Test
5% Shapiro Wilk Critical Value
0.748
Data Not Normal at 5% Significance Level
Lilliefors Test Statistic
0.307
Lilliefors GOF Test
5% Lilliefors Critical Value
0.375
Data appear Normal at 5% Significance Level
Data appear Approximate Normal at 5% Significance Level
Background Statistics Assuming Normal Distribution
95% UTL with 95% Coverage
136.1
90% Percentile (z)
103.5
95% UPL (t)
114.9
95% Percentile (z)
106.6
95% USL
105
99% Percentile (z)
112.3

Gamma GOF Test
A-D Test Statistic
0.706
Anderson -Darling Gamma GOF Test
5% A-D Critical Value
0.657
Data Not Gamma Distributed at 5% Significance Level
K-S Test Statistic
0.341
Kolmogorov-Smirnov Gamma GOF Test
5% K-S Critical Value
0.394
Detected data appear Gamma Distributed at 5% Significance Level
Detected data follow Appr.
Gamma Distribution at 5% Significance Level
Gamma Statistics
k hat (MLE)
160.9
k star (bias corrected MLE)
40.39
Theta hat (MLE)
0.576
Theta star (bias corrected MLE)
2.295
nu hat (MLE)
1287
nu star (bias corrected)
323.1
MLE Mean (bias corrected)
92.7
MLE Sd (bias corrected)
14.59
Background Statistics Assuming Gamma Distribution
95% Wilson Hilferty (WH) Approx. Gamma UPL
116.5
90% Percentile
111.8
95% Hawkins Wixley (HW) Approx. Gamma UPL
116.7
95% Percentile
117.9
95% WH Approx. Gamma UTL with 95% Coverage
143
99% Percentile
130
95% HW Approx. Gamma UTL with 95% Coverage
144.1
95% WH USL
105.4
95% HW USL 105.4
Lognormal GOF Test
Shapiro Wilk Test Statistic
0.737
Shapiro Wilk Lognormal GOF Test
5% Shapiro Wilk Critical Value
0.748
Data Not Lognormal at 5% Significance Level
Lilliefors Test Statistic
0.307
Lilliefors Lognormal GOF Test
5% Lilliefors Critical Value
0.375
Data appear Lognormal at 5% Significance Level
Data appear Approximate Lognormal at 5% Significance Level
Background Statistics assuming Lognormal Distribution
95% UTL with 95% Coverage
147.7
90% Percentile (z)
103.9
95% UPL (t)
117.5
95% Percentile (z)
107.4
95% USL
105.6
99% Percentile (z)
114.2
Nonparametric Distribution Free Background Statistics
Data appear Approximate Normal at 5% Significance Level
Nonparametric Upper Limits for Background Threshold Values
Order of Statistic, r
4
95% UTL with 95% Coverage
100
Approx, f used to compute achieved CC
0.211
Approximate Actual Confidence Coefficient achieved by UTL
0.185
Approximate Sample Size needed to achieve specified CC
59
95% Percentile Bootstrap UTL with 95% Coverage
N/A
95% BCA Bootstrap UTL with 95% Coverage
N/A
95% UPL
100
90% Percentile
100
90% Chebyshev UPL
121
95% Percentile
100
95% Chebyshev UPL
133.8
99% Percentile
100
95% USL
100
Note: The use of USL tends to yield a conservative estimate of BTV, especially when the sample size starts exceeding 20.
Therefore, one may use USL to estimate a BTV only when the data set represents a background data set free of outliers
and consists of observations collected from clean unimpacted locations.
The use of USL tends to provide a balance between false positives and false negatives provided the data

represents a background data set and when many onsite observations need to be compared with the BTV.
silver
General Statistics
Total Number of Observations
0
Number of Distinct Observations
0
Number of Missing Observations
5
Minimum
N/A
First Quartile
N/A
Second Largest
N/A
Median
N/A
Maximum
N/A
Third Quartile
N/A
Mean
N/A
SD
N/A
Coefficient of Variation
N/A
Skewness
N/A
Warning: This data set only has 0 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable silver was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
sodium
General Statistics
Total Number of Observations
0
Number of Distinct Observations
0
Number of Missing Observations
5
Minimum
N/A
First Quartile
N/A
Second Largest
N/A
Median
N/A
Maximum
N/A
Third Quartile
N/A
Mean
N/A
SD
N/A
Coefficient of Variation
N/A
Skewness
N/A
Warning: This data set only has 0 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable sodium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
thallium
General Statistics
Total Number of Observations
2
Number of Missing Observations
3
Number of Distinct Observations
1
Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
10
Maximum Detect
N/A
Maximum Non -Detect
10
Variance Detected
N/A
Percent Non -Detects
100%

Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable thallium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
vanadium
General Statistics
Total Number of Observations
2
Number of Missing Observations
3
Number of Distinct Observations
1
Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
5
Maximum Detect
N/A
Maximum Non -Detect
5
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable vanadium was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
zinc
General Statistics
Total Number of Observations
2
Number of Missing Observations
3
Number of Distinct Observations
1
Number of Detects
0
Number of Non -Detects
2
Number of Distinct Detects
0
Number of Distinct Non -Detects
1
Minimum Detect
N/A
Minimum Non -Detect
30
Maximum Detect
N/A
Maximum Non -Detect
30
Variance Detected
N/A
Percent Non -Detects
100%
Mean Detected
N/A
SD Detected
N/A
Mean of Detected Logged Data
N/A
SD of Detected Logged Data
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable zinc was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!

If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.
Hardness
General Statistics
Total Number of Observations
2
Number of Distinct Observations
2
Number of Missing Observations
3
Minimum
53600
First Quartile
53700
Second Largest
53600
Median
53800
Maximum
54000
Third Quartile
53900
Mean
53800
SD
282.8
Coefficient of Variation
0.00526
Skewness
N/A
Warning: This data set only has 2 observations!
Data set is too small to compute reliable and meaningful statistics and estimates!
The data set for variable Hardness was not processed!
It is suggested to collect at least 8 to 10 observations before using these statistical methods!
If possible, compute and collect Data Quality Objectives (DQO) based sample size and analytical results.

Appendix C - DEQ Risk Calculator Documentation
Appendix C-1
Exposure Point Concentration Tables
Appendix C-2
Exposure Unit #1 — Resident and Non -Residential Worker
(0-2 ft bgs soil samples, background concentrations included)
Appendix C-3
Exposure Unit #1 — Construction Worker
(0-10 ft bgs soil samples, background concentrations included)
Appendix C-4
Exposure Unit #2 Trail — Greenway User and Construction Worker
(soil samples, background concentrations included)
Appendix C-5
Exposure Unit #2 Creek — Greenway User
(sediment and surface water samples, background concentrations included)
Appendix C-6
Exposure Unit #3 — Resident, Non -Residential Worker, and Greenway User
(0-2 ft bgs soil samples, background concentrations included)
Appendix C-7
Exposure Unit #3 - Construction Worker
(0-10 ft bgs soil samples, background concentrations included)
Appendix C-8
Exposure Unit #1 — Resident and Non -Residential Worker
(0-2 ft bgs soil samples, background concentrations excluded)
Appendix C-9
Exposure Unit #1 — Construction Worker
(0-10 ft bgs soil samples, background concentrations excluded)
Appendix C-10
Exposure Unit #2 Trail — Greenway User and Construction Worker
(soil samples, background concentrations excluded)
Appendix C-11
Exposure Unit #2 Creek — Greenway User
(sediment and surface water samples, background concentrations excluded)
Appendix C-12
Exposure Unit #3 — Resident, Non -Residential Worker, and Greenway User
(0-2 ft bgs soil samples, background concentrations excluded)
Appendix C-13
Exposure Unit #3 - Construction Worker
(0-10 ft bgs soil samples, background concentrations excluded)

Appendix C-1 Exposure Point Concentration Tables
Exposure Unit #1
Direct Contact to Soil Pathway
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job. No. TCH-009
E
E
E
o
Sample ID
Sample Date
Material Sampled
Sample Depth
o
0
(Soil or CCP)
E
E
N
E
E
U
7
_7
E
(a
C
_
i
_
_7
E
Z)
E
7
(0
co
'
(6
Q
i
c
CZ
(6
(a
-0
-0
co
t
O
O
C
E
E
C
�
C
�
>
N
Site -Specific BSV
3.015
87.86
0.929
0.313
5.725
70.2
36.31
77.3
59.11
1,149
0.256
19.49
2.503
43.19
0.981
227
230
S-4
04/29/13
CCP
1 ft
14
24
ND
1.5
NA
30
65
20
1,500
0.011
43
ND
NA
ND
21
120
S-5*
01/31/14
CCP
0-4 ft
37
2,800
NA
ND
1.3
19.7
NA
NA
10
�A
0.30
NA
3.2
NA
NA
NA
NA
S-6*
01/31/14
CCP
0-4 ft
43
3,200
NA
ND
2.7
19.3
NA
NA
12
NA
0.42
NA
6.1
NA
NA
NA
NA
GP-1
02/03/14
CCP
8-12 ft
3.5
86
NA
ND
ND
8.8
NA
NA
26
NA
0.083
NA
ND
NA
NA
NA
NA
GP-2
02/03/14
CCP
26-28 ft
41
1,100
NA
ND
ND
19
NA
NA
11
NA
0.24
NA
4.0
NA
NA
NA
NA
GP-3
02/03/14
CCP
10-12 ft
48
1,200
NA
ND
0.53
22.47
NA
NA
39
NA
0.42
NA
ND
NA
NA
NA
NA
GP-4
02/04/14
CCP
10-12 ft
59
2,900
NA
ND
ND
20
NA
NA
11
NA
0.51
NA
5.8
NA
NA
NA
NA
02/04/14
CCP
4-6 ft
72
2,800
NA
ND
ND
19
NA
NA
9.5
NA
0.33
NA
2.6
NA
NA
NA
NA
GP-5
04/03/19
CCP
4-6 ft
95.9
2,350
5.46
<0.956
0.836 J
12.3
7.05
50.9
NA
34.7
1.2
11.1
12
325
NA
NA
NA
04/03/191
CCP
4-6 ft
95.9
2,630
6.99
<0.931
0.712 J
16.2
1 10.3
62.5
NA
53.4
0.39
17.1
308
NA
NA
NA
GP-6
02/04/14
CCP
9-11 ft
65
850
NA
ND
ND
19
NA
NA
27
NA
11
NA
4.1
NA
NA
NA
NA
04/04/19
CCP
9-10 ft
6.73
178
0.758
0.118 J
<1.11
10.0
5.18
11
NA
687
0.05
6.24
0.88
21.7
NA
NA
NA
GP-7
02/04/14
CCP
10-12 ft
55
1,700
NA
ND
ND
19
NA
NA
11
NA
0.26
NA
4.3
NA
NA
NA
NA
GP-8
02/04/14
CCP
11-15 ft
54
4,100
NA
ND
ND
20
NA
NA
9.2
NA
0.29
NA
4.5
NA
NA
NA
NA
GP-11
02/04/14
CCP
4-6 ft
16
450
NA
ND
ND
16
NA
NA
23
NA
0.35
NA
ND
NA
NA
NA
NA
GP-12
02/04/14
CCP
2-4 ft
52
2,000
NA
ND
ND
19
NA
NA
14
NA
0.28
NA
2.1
NA
NA
NA
NA
11/03/16
Soil
0-1 ft
5.9
120
1.00
<0.29
0.45
20.55
7.9
25
27
350
0.052
8.8
0.69
31
<0.58
48
50
HH-1
11/03/16'
Soil
0-1 ft
3.4
110
0.79
<0.35
0.54
19.46
8.4
17
18
360 BH
0.067
12
<0.71
30
<0.71
1 41
35
HH-2
11/03/16
Soil
0-1 ft
4.9
140
0.93
<0.29
0.43
13.57
12
21
30
260
0.085
5.9
1 1.0
25
<0.58
48
43
HH-3
11/03/16
Soil
0-1 ft
9.9
200
1.30
<0.33
0.46 J
17.54
7.8
31
24
350
0.076
1
36
<0.65
53
100
HH-4
11/03/16
Soil
0-1 ft
2.4
72
1.00
<0.28
0.50
44.5
1 16
37
2.3
630
<0.023
33
<0.56
42
0.60
73
70
HH-5
11/03/16
Soil
0-1 ft
2.4
73
0.75
<0.30
<0.14
23
8.4
19
9.3
410
<0.025
1 14
1.2
23
<0.60
39
51
MW-7
11/01/16
Soil
0-1 ft
2.6
67
1 0.87
<0.30
0.89
9.11
3.9
1 180
7.6
100
0.030
2.9
<0.59
6.7
<0.59
61
1 46
Maximum Concentrations -All Samples
95.9
4,100
6.99
1.5
2.7
44.5
30
180
IF39
1,500
11
13
325
0.60
73
120
Maximum Concentrations - Shallow (0-2') Interval
14
200
1.30
1.5
0.89
44.5
30
180
30
1,500
0.085
4
2.4
42
0.60
73
120
Maximum Concentrations - Construction Worker (0-10') Interval
95.9
3,200
6.99
1.5
2.7
44.5
30
180
30
1,500
11
13
325
0.60
73
120
Notes:
Red indicates concentration is below recommended site -specific background screening value (BSV).
Orange shading indicates maximum concentration in all samples.
Blue shading indicated maximum concentrations in samples that include the shallow (0-2 ft) interval.
Purple shading indicates maximum concentrations in samples that include the 0-10 ft interval.
Grey shading indicates concentration is maximum concentration in all use scenarios.
' Duplicate sample taken.
CCP = Coal Combustion Product; ND = Not Detected; NA = Not Analyzed.
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
BH = Method blank greater than one-half laboratory reporting limit, but sample concentration greater than 10x the method blank.
*Location resampled at 0-1 ft interval (HH-2 and HH-5); 0-1 ft sample considered more representative of shallow interval.
https://harthick.sharepoint.com/sites/MasterFiles-1/Shared Documents/AAA-Master Projects/Town of Chapel Hill (TCH)/TCH-009 - Police Station - Remedial Services/Risk Assessment/Tables/C-1 EPC Tables.xlsx Hart & Hickman, Pl.

Appendix C-1 Exposure Point Concentration Tables
Exposure Unit #2
Direct Contact to Soil Pathway
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job. No. TCH-009
E
E
o
2
Sample
Material Sampled (Soil or
Sample
o
Sample ID
Date
CCP)
Depth
c
U
7
7
2
E
E
7
L
L
E
>
f6
X
N
""
f6
N
Q
0-
C
7
U
L
N
Y
0)
C
o
-
-U
f6
C:
U
f6
U
L
L
-0
O
O
N
E
E
C
to
>
N
Site -Specific BSV
3.015
87.86
0.929
0.313
5.725
70.2
36.31
77.3
59.11
1,149
0.256
19.49
2.503
43.19
0.981
227
230
SS-7
02/18/16
Soil
2-12 in
3.1
84
0.60
ND
NA
NA
6.9
15
13
500
0.038
5.9
ND
31
ND
37
37
HH-8
10/27/16
Soil
0-1 ft
3.6
100
1.00
<0.30
<0.35
19
12
29
18
570
0.036
9.0
<0.60
28
<0.60
52
54
MW-6
11/02/16
Soil
0-1 ft
2.9
38
0.61
<0.26
0.21 J
9.79
9.5
23
12
570
0.082
8.2
1.0
22
0.81
31
77
SED-3A
04/05/19
Soil
0-1 ft
3.45
33.9
0.418 J
<0.582
<1.16
17.4
16.5
6.97
560
<0.0054
5.82
0.237 J
9.6
SED-5A
04/04/19
Soil
0-1 ft
1.25
13.5
0.156 J
<0.571
0.352 J
13.2
5.95
39.1
243
0.0071
4.38
<0.571
10.9
SED-8
04/05/19
Drainage Pathway Soil
2-6 in
2.41
49.1
0.313 J
0.122 J
<1.25
12.0
7.01
14.3
423
0.063
4.66
1.01
15.2
SED-9
04/05/19
Drainage Pathway Soil
2-6 in
1.16
33.8
0.199 J
<0.660
0.461 J
21.6
9.11
10.1
431
0.013
6.68
<0.660
16.7
SED-10
04/05/19
Drainage Pathway Soil
2-6 in
1.29
24.4
0.118 J
0.221 J
0.418 J
12.0
4.43
10.8
195
0.037
4.03
0.273 J
8.1
SED-12
08/27/19
Drainage PathwaySoil
0-2 in
4.73
102
0.765 J
0.214 J
<1.68
27.6
6.17
23.1
341
0.042
7.69
0.961
25.4
04/05/19
Drainage Pathway Soil
2-6 in
3.97
122
0.499 J
0.204 J
<1.74
9.45
6.04
19.7
319
0.077
4.95
1.36
32.8
SED-13
08/27/19
Drainage Pathway Soil
0-2 in
12.4
958
1.56
0.284 J
<2.03
29.4
13.9
38.9
538
0.12
19.2
3.07
125
04/05/19
Drainage Pathway Soil
2-6 in
14.5
724
1.1
0.171 J
<1.58
14.0
7.58
27.1
563
0.075
8.73
1.69
70.5
NA
SED-18
04/05/19
Drainage Pathway Soil
2-6 in
4.53
137
0.534 J
<0.689
<1.38
18.7
11.1
28.2
464
0.051
9
1.85
32.6
SED-19
04/05/19
Drainage Pathway Soil
2-6 in
1.55
20
0.161 J
<0.588
0.435 J
21.7
7.98
8.38
266
0.0073
4.94
0.334 J
15
SED-20
04/05/19
Drainage Pathway Soil
2-6 in
0.792
31.4
0.152 J
<0.687
<1.37
5.76
4.5
9.1
360
0.012
2.19
0.263 J
11.5
SED-21
04/05/19
Drainage Pathway Soil
2-6 in
1.12
25.9
0.149 J
<0.591
<1.18
20.9
4.44
6.58
221
0.011
2.7
0.286 J
12.8
iWk
Excavation G-1
04/16/20
Soil
2-3 ft
3.68
58.8
<3.08
<1.23
0.478 J
20.0
5.73
14.5
193
0.052
6.94
<3.08
6.2
NA
NA
NA
Excavation H-3
05/11/20
Soil
1-2 ft
2.41
71.0
<3.28
<1.31
0.410 J
40.2
14.1
43.4
251
0.0485 J
12.5
1.46 J
58.1
NA
NA
NA
Excavation H-5
05/11/20
Soil
1-2 ft
1.10 J
74.5
<3.04
<1.22
0.497 J
21.1
8.25
16.9
558
<0.0486
6.77
<3.04
32.2
NA
NA
NA
Excavation H-6
05/11/20
Soil
1-2 ft
1.02 J
96.0
<2.97
<1.19
<1.19
14.9
7.57
10.7
557
0.0222 J
4.03
<2.97
20.5
NA
NA
NA
Excavation H-7
11/09/20
Soil
0-1 ft
1.10 J
73.7
0.767 J
<1.22
<1.22
8.04
3.68
15.0
233
0.022
4.63
0.479 J
9.6
NA
NA
NA
Excavation 1-1
04/08/20
Soil
1-2 ft
2.91
67.2
<2.77
<1.11
0.457 J
26.2
13.0
18.3
594
0.042
8.25
<2.77
26.3
NA
NA
NA
Excavation 1-2
04/08/20
Soil
1-2 ft
3.65
74.1
<2.85
<1.14
0.313 J
23.3
12.0
21.4
544
0.022
8.70
<2.85
17.2
NA
NA
NA
Excavation 1-3
04/08/20
Soil
1-2 ft
2.18
61.5
<2.88
<1.15
0.387 J
13.1
9.23
19.5
419
0.019
6.02
<2.86
13.3
NA
Maximum Concentrations*
14.5
958
1.56
0.284
0.497
40.2
16.5
43.4
18
594
0.12
19.2
3.07
7125
0.81
52
77
Notes:
Red indicates concentration is below recommended site -specific background screening value (BSV).
Orange shading indicates maximum exposure unit concentration.
CCP = Coal Combustion Product; ND = Not Detected; NA = Not Analyzed.
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
Site -Specific Background Screening Value (BSV) represents 95% upper threshold level (UTL) with 95% coverage calculated using EPA ProUCL 5.1.
*Maximum concentration for samples collected in shallow (0-2 ft) soil interval are the same as maximum concentrations.
https://harthick.sharepoint.com/sites/MasterFiles-1/Shared Documents/AAA-Master Projects/Town of Chapel Hill (TCH)/TCH-009 - Police Station - Remedial Services/Risk Assessment/Tables/C-1 EPC Tables.xlsx Hart Hickman, Pl.

Appendix C-1 Exposure Point Concentration Tables
Exposure Unit #2
Direct Contact to Sediment Pathway
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job. No. TCH-009
E
E
E
Sediment
°
ff
Sampling Point
Sample Date
_r_
°
ID
E
"
c
E
E
_U
C
E
7
(a
C
_co7
0)
>
N
C
7
i
(a
X
,
(6
Q
Q
C
U
Y
N
C
(4
-0
-0
L
U
U
E
E
C
(n
)
Recommended Site
-Specific BSV
2.74
38.4
0.48
0.79
69.5
16.388
13.8
759
0.0078
9.92
0.409
16.9
SED-3 (Adjacent)
04/05/19
1.36
16.4
0.111 J
0.670 J
13.5
5.18
20.2
225
0.0054 J
4.81
�.e07
9.2
SED-4 (Adjacent)
04/05/19
2.35
20.3
0.191 J
0.456 J
63.8
7.26
8.39
293
0.0080
10.5
0.344 J
30.7
SED-5
04/04/19
1.82
'^ °
0.233 J
0.595 J
16.8
1
5.9
8.86
'`).0035
4.86
<0.617
6.2
Downstream
Maximum Concentrations
2.35
0.233
0.670
63.8
7.26
20.2
0.0080
10.5
0.344
30.7
Notes:
Red indicates concentration is below recommended site -specific background screening value (BSV).
Orange shading indicates maximum exposure unit concentration.
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
https://harthick.sharepoint.com/sites/MasterFiles-1/Shared Documents/AAA-Master Projects/Town of Chapel Hill (TCH)/TCH-009 - Police Station - Remedial Services/Risk Assessment/Tables/C-1 EPC Tables.xlsx Hart & Hickman, Pl.

Appendix C-1 Exposure Point Concentration Tables
Exposure Unit #2
Direct Contact to Surface Water Pathway
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job. No. TCH-009
E
Surface Water
E
°n'
Sample Date
o
E
Sampling Point ID
c,
'E
B
N�
N
E
E
E
_0
0
0
Vi
Recommended Site
-Specific BSV
0.44
27
0.53
0.16
1.2
22.2
0.33
0.11
100
11/03/16
27
34
100
SW-3 (Adjacent)
11/03/161
27
33
110
04/05/19
0.45
25.7
0.62
0.26
2.8
37.4
0.50
0.11 J
88.8
11/03/16
27
<5.0
1 <5.0
25
<10
<20
110
SW-4 (Adjacent)
04/05/19
0.42
23.6
<0.50
0.14
1.0
24.6
0.26 J
0.10 J
89.1
04/05/191
0.41
23.7
<0.50
0.14
0.98
24.8
0.26 J
0.088 J
87.7
11/03/16
<10
26
<5.0
<5.0
1 24
<10
<2n
100
SW-5 (Downstream)
04/04/19
0.40
16.9
<0.50
0.14
0.88
19.5
0.21 J
0.12 J
81.8
SW-21 (Drainage
04/05/19
0.40
32.1
0.73
0.36
3.2
29.5
0.62
0.11 J
69.9
04/05/192
0.15
18.3
<0.50
0.094 J
3.1
9.3
0.43 J
<0.50
43.5
Pathway)
Maximum Concentrations
1 0.45
1 32.1
0.73
0.36
3.2
37.4
1 0.62
1 0.12
1 110
Notes:
Red indicates concentration is below recommended site -specific background screening value (BSV).
Orange shading indicates maximum exposure unit concentration.
Duplicate sample taken.
2 Sample was field filtered.
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
https://harthick.sharepoint.com/sites/MasterFiles-1/Shared Documents/AAA-Master Projects/Town of Chapel Hill (TCH)/TCH-009 - Police Station - Remedial Services/Risk Assessment/Tables/C-1 EPC Tables.xlsx Hart & Hickman, PC

Appendix C-1 Exposure Point Concentration Tables
Exposure Unit #3
Direct Contact to Soil Pathway
828 Martin Luther King, Jr. Blvd.
Chapel Hill, North Carolina
H&H Job. No. TCH-009
E
E
Material
o
�2
Sample
Sampled
Sample
o
Sample ID
N
Date
(Soil or
Depth
c
CCP)
�_
_�
m
c
_
N
7
_�
E
"p
(6
X
N
co
(6
Q
Q
V
L
Y
_n
O
fa
�
-0
U
t
i
-0
O
O
co
E
=
0
C
to
to
Recommended Site -Specific BSV
3.015
87.86
0.929
0.313
5.725
70.2
36.31
77.3
1,149
0.256
19.49
2.503
43.19
HH-9
04/03/19
CCP
0-1 ft
3.37
131
0.398 J
0.178 J
<1.29
12.7
5.97
14.5
260
0.31
3.59
0.722
33.2
HH-10
04/03/19
CCP
0-1 ft
60.3
2,970
5.14
0.162 J
<1.60
13.8
9.84
51.3
73.3
0.22
17.1
5.04
269
HH-11
04/03/19
CCP
0-1 ft
42.5
3,260
5.9
0.220 J
0.467 J
18.7
13.4
55.3
113
0.43
23.5
9.05
234
S-7
01/31/14
CCP
0-4 ft
44
2,500
ivH
ND
1.4
27.6
NA
NA
11
NA
0.44
NA
4.5
Excavation H-1
05/11/20
Soil
1-2 ft
1.16
37.2
<2.76
<1.10
<1.10
20.1
10.7
15.3
412
<0.0442
5.80
<2.76
29.3
Excavation H-2
05/11/20
Soil
1-2 ft
1.93
100
<3.25
<1.30
0.578 J
43.8
19.1
59.2
265
0.0494 J
16.2
1.58 J
56.8
Excavation H-4
05/11/20
Soil
2-3 ft
2.03
67.1
<3.04
<1.22
0.388 J
25.8
20.8
24.0
1,480
0.0237 J
7.81
<3.0z'
38.1
Maximum Concentrations
60.3
3,260
5.9
0.220
1.4
43.8
20.8
59.2
1,480
0.43
23.5
9.05
269
Maximum Concentrations - Shallow Interval Only
60.3
1 3,260
5.9
0.220
1.4
43.8
19.1
59.2
412
0.43
23.5
9.05
269
Notes:
Red indicates concentration is below recommended site -specific background screening value (BSV).
Orange shading indicates maximum exposure unit concentration.
CCP = Coal Combustion Product.
J = Detected above method detection limit but below laboratory reporting limit; therefore, result is an estimated concentration.
https://harthick.sharepoint.com/sites/MasterFiles-1/Shared Documents/AAA-Master Projects/Town of Chapel Hill (TCH)/TCH-009 - Police Station - Remedial Services/Risk Assessment/Tables/C-1 EPC Tables.xlsx Hart & Hickman, Pl.

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU #1 Resident & Non -Residential Worker
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU #1 Resident & Non -Residential Worker
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
0
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
El
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
❑
Output Form 2F
Recreator/Trespasser Soil
❑
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 3D
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 Resident & Non -Residential Worker
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
0
Groundwater Use
❑
Non -Residential Worker
Soil
0
Groundwater Use
❑
Construction Worker
Soil
❑
Recreator/Trespasser
Soil
❑
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 Resident & Non -Residential Worker
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
EL
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (cm2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (cm2)
19652
19
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0,71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm2)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SAj (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 Resident & Non -Residential Worker
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
195
Exposure Time (ET) (hr)
2
NA
2
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
2
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
195
Exposure Time (ET) (hr)
2
2
2
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0955
Water Exposure Time (ET_,) (hr/event)
2
2
2
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
Unit ID: EU #1 Resident & Non -Residential Worker
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from shallow samples (0-2 ft) collected within the exposure unit.
NOTE: If the chemical list is chaneed from a prior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Concentration
(mg/kg)
Notes:
CAS Number
Chemical
For the chemicals highlighted in blue, data entry notes are provided in the
PSRG Table link on the Main Menu
Minimum
Concentration
(Qualifier)
Maximum
Concentration
(Qualifier)
Units
Location of
Maximum
Concentration
on
Detection
Frequency
Range of
Detection Limits
Concentration
Used for
Screening
Background
Value
Screening
Toxicity Value
(Screening
Level) (n/c)
Potential
ARAR/TBC
Value
Potential
ARAR/TBC
Source
COPC
Flag
(Y/N)
Rationale for
Selection or
Deletion
14
S-4
7440-38-2
Arsenic, Inorganic
mg/kg
200
HH-3
7440-39-3
Barium
mg/kg
1.3
HH-3
7440-41-7
Beryllium and compounds
mg/kg
1.5
S-4
7440-43-9
Cadmium (Diet) r
mg/kg
44.5
HH4
16065-83-1
Chromium(III), Insoluble Salts
mg/kg
0.89
MW-7
18540-29-9
Chromium(VI)
mg/kg
30
S-4
7440-48-4
Cobalt
mg/kg
180
MW-7
7440-50-8
Copper
mg/kg
30
HH-2
7439-92-1
Lead and Compounds
mg/kg
1500
S-4
7439-96-5
Manganese (Non -diet)
mg/kg
0.085
HH-2
7439-97-6
Mercury (elemental)
mg/kg
43
S-4
7440-02-0
Nickel Soluble Salts
mg/kg
2.4
HH-3
7782-49-2
Selenium
mg/kg
42
HH4
7440-24-6
Strontium, Stable
mg/kg
0.6
HH4
7440-28-0
Thallium (Soluble Salts)
mg kg
73
HH-4
7440-62-2
Vanadium and Compounds
mg/kg
120
S-4
7440-66-6
Zinc and Compounds
mg/kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 Resident & Non -Residential Worker
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
2.4E-05
3.6E+00
YES
Groundwater Use*
NC
NC
NC
Non -Residential Worker
Soil
4.8E-06
2.4E-01
NO
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
NC
NC
NC
Recreator/Trespasser
Soil
NC
NC
NC
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

N,dh Carolina DEQ -k Calculator

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU #1 Construction Worker
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU #1 Construction Worker
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
❑
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
❑
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
El
Output Form 2F
Recreator/Trespasser Soil
❑
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 3D
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 Construction Worker
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
❑
Groundwater Use
❑
Non -Residential Worker
Soil
❑
Groundwater Use
❑
Construction Worker
Soil
0
Recreator/Trespasser
Soil
❑
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 Construction Worker
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (CM 2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (CM 2)
19652
19652
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0.71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm2)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
�L&
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA) (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 Construction Worker
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
195
Exposure Time (ET) (hr)
2
NA
2
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
2
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
195
Exposure Time (ET) (hr)
2
2
2
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0955
Water Exposure Time (ET_,) (hr/event)
2
2
2
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
Unit ID: EU #1 Construction Worker
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from samples collected between 0 to 10 ft within the exposure unit.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Concentration
(mg/kg)
Notes:
CAS Number
Chemical
For the chemicals highlighted in blue, data entry notes are provided in the
PSRG Table link on the Main Menu
Minimum
Concentration
(Qualifier)
Maximum
Concentration
(Qualifier)
Units
Location of
Maximum
Concentration
on
Detection
Frequency
Range of
Detection Limits
Concentration
Used for
Screening
Background
Value
Screening
Toxicity Value
(Screening
Level) (n/c)
Potential
ARAR/TBC
Value
Potential
ARAR/TBC
Source
COPC
Flag
(Y/N)
Rationale for
Selection or
Deletion
95.9
GP-5
7440-38-2
Arsenic, Inorganic
mg/kg
3200
S-6
7440-39-3
Barium
mg/kg
6.99
GP-5
7440-41-7
Beryllium and compounds
mg/kg
1.5
S-4
7440-43-9
Cadmium (Diet) r
mg/kg
44.5
HH4
16065-83-1
Chromium(III), Insoluble Salts
mg/kg
2.7
S-6
18540-29-9
Chromium(VI)
mg/kg
30
S-4
7440-48-4
Cobalt
mg/kg
180
MW-7
7440-50-8
Copper
mg/kg
30
HH-2
7439-92-1
Lead and Compounds
mg/kg
1500
S-4
7439-96-5
Manganese (Non -diet)
mg/kg
11
GP-6
7439-97-6
Mercury (elemental)
mg/kg
43
S-4
7440-02-0
Nickel Soluble Salts
mg/kg
13
GP-5
7782-49-2
Selenium
mg/kg
325
GP-5
7440-24-6
Strontium, Stable
mg/kg
0.6
HH4
7440-28-0
Thallium (Soluble Salts)
mg kg
73
HH-4
7440-62-2
Vanadium and Compounds
mg/kg
120
S-4
7440-66-6
Zinc and Compounds
mg/kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 Construction Worker
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Non -Residential Worker
Soil
NC
NC
NC
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
7.0E-06
1.1E+01
YES
Recreator/Trespasser
Soil
NC
NC
NC
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU #2 Lower Level Trail - Greenway User and Construction Worker
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU #2 Lower Level Trail - Greenway User and Construction Worker
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
❑
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
❑
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
El
Output Form 2F
Recreator/Trespasser Soil
0
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 3D
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Trail - Greenway User and Construction Woi
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
❑
Groundwater Use
❑
Non -Residential Worker
Soil
❑
Groundwater Use
❑
Construction Worker
Soil
0
Recreator/Trespasser
Soil
0
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Trail - Greenway User and Construction Worker
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (CM 2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (CM 2)
19652
19652
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0.71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm2)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
�L&
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA) (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Trail - Greenway User and Construction Worker
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
70
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
52
98th percentile based on trail use polling data
Exposure Time (ET) (hr)
2
NA
0.5
98th percentile based on trail use polling data
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
0.5
98th percentile based on trail use polling data
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
SO
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
364
98th percentile based on trail use polling data
Exposure Time (ET) (hr)
2
2
1
98th percentile based on trail use polling data
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0955
Water Exposure Time (ET_„) (hr/event)
2
2
1
98th percentile based on trail use polling data
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
osure Unit ID: EU #2 Lower Level Trail - Greenwav User and Construction Worker
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from all samples collected within the exposure unit. Note that all maximum concentrations were within the 0-2 ft bgs interval; therefore, both the construction worker and greenway user receptor were evaluated.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Concentration
(mg/kg)
Notes:
CAS Number
Chemical
For the chemicals highlighted in blue, data entry notes are provided in the
PSRG Table link on the Main Menu
Minimum
Concentration
(Qualifier)
Maximum
Concentration
(Qualifier)
Units
Location of
Maximum
Concentration
on
Detection
Frequency
Range of
Detection Limits
Concentration
Used for
Screening
Background
Value
Screening
Toxicity Value
(Screening
Level) (n/c)
Potential
ARAR/TBC
Value
Potential
ARAR/TBC
Source
COPC
Flag
(YQ�
Rationale for
Selection or
Deletion
14.5
SED-13
7440-38-2
Arsenic, Inorganic
mg/kg
958
SED-13
7440-39-3
Barium
mg/kg
1.56
SED-13
7440-41-7
Beryllium and compounds
mg/kg
0.284
SED-13
7440-43-9
Cadmium (Diet) r
mg/kg
40.2
Excavation H-3
16065-83-1
Chromium(III), Insoluble Salts
mg/kg
0.497
Excavation H-5
18540-29-9
Chromium(VI)
mg/kg
16.5
SED-3A
7440-48-4
Cobalt
mg/kg
43.4
Excavation H-3
7440-50-8
Copper
mg/kg
18
HH-8
7439-92-1
Lead and Compounds
mg/kg
594
Excavation I-1
7439-96-5
Manganese (Non -diet)
mg/kg
0.12
SED-13
7439-97-6
Mercury (elemental)
mg/kg
19.2
SED-13
7440-02-0
Nickel Soluble Salts
mg/kg
3.07
SED-13
7782-49-2
Selenium
mg/kg
125
SED-13
7440-24-6
Strontium, Stable
mg/kg
0.81
MW-6
7440-28-0
Thallium (Soluble Salts)
mg kg
52
HH-8
7440-62-2
Vanadium and Compounds
mg kg
77
MW-6
7440-66-6
Zinc and Compounds
mg/kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Trail - Greenway User and Construction Worker
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Non -Residential Worker
Soil
NC
NC
NC
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
1.4E-06
3.6E+00
YES
Recreator/Trespasser
Soil
8.4E-06
4.1E-01
NO
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

DEQ Risk Calculator - Direct Contact- Construction Worker Soil
Version Date: June 2021
Baata: May 2021 EPA RSL Table
t
Site ID: BPN 21061-17-060
Ex os re Unit ID: EU #2 Lower Level Trail - Greenwa User and Construction Worker
' - Note that inhalation on this calculator refers to outdoor inhalation gfvolatiles and particulates, not indoor inhalation associated with vapor intrusion.
" - Now that the EPA has no consensus on reference dose or cancer slope factor valuesfor lead, therefore it is not possible to calculate cancer risk or hazard quotient Lead concentrations are compared
mglkgfor commerciallinduscrial soil.
to the EPA screening level of800
7440-66-6
Zinc and Compounds
77
77
77
Cumulative:
1.4E-06
7.6E-04
7.6E-04
3.6E+00
CAS #
Chemical Name:
Ingestion
Concentrator
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentrator
(mg/kg)*
Ingestion
Carcinogenic
Risk
Demtal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Rink
Ingestion
Hazard
Quotient
Demtal
Hazard
Quotient
Inhalator
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
14.5
14.5
14.5
5.3E-07
8.4E-08
1.9E-07
8.0E-07
8.5E-02
1.4E-02
2.2E-01
3.2E-01
7440-39-3
Barium
958
958
958
1.4E-02
4.3E-02
5.7E-02
7440-41-7
Beryllium and compounds
1.56
1.56
1.56
1.2E-08
1.2E-08
9.2E-04
1.8E-02
1.8E-02
7440-43-9
Cadmium (Diet)
0.284
0.284
0.284
1.6E-09
1.6E-09
1.7E-03
2.1E-04
6.4E-03
8.3E-03
16065-83-1
Clvomimn(III), Insoluble Salts
40.2
40.2
40.2
7.9E-05
1.8E-03
1.9E-03
18540-29-9
Clvomimn(VI)
0.497
0.497
0.497
1.0E-08
1.3E-07
1.4E-07
2.9E-04
3.7E-04
6.6E-04
7440-48-4
Cobalt
16.5
16.5
16.5
4.6E-07
4.6E-07
1.6E-02
1.9E-01
2.0E-01
7440-50-8
Cooper
43.4
43.4
43.4
1.3E-02
1.3E-02
7439-92-1
-Lead and Compounds
18
18
18
GSL**
<SL**
<SL**
7439-96-5
Manganese (Non -diet)
594
594
594
7.3E-02
2.7E+00
2.7E+00
7439-97-6
m
-Mercury (eleental)
0.12
0.12
0.12
1.2E-02
1.2E-02
7440-02-0
Nickel Soluble Salts
19.2
19.2
19.2
1.5E-08
1.5E-08
2.8E-03
2.2E-02
2.4E-02
7782-49-2
Selenimn
3.07
3.07
3.07
1.8E-03
3.4E-OS
1.8E-03
7440-24-6
Strontimn, Stable
125
125
125
1.8E-04
1.8E-04
7440-28-0
Thallium, (Soluble Salts)
0.81
0.81
0.81
6.0E-02
6.0E-02
!MIN
Vanadimn and Compounds
52
52
52
1.5E-02
1.2E-Ol
1.3E-01

DEQ Risk Calculator - Direct Contact - Recreator/Tres a er Soil
Version Date: June 2021
Basis: May 2021 EPA RSL Table
s
Site ID: BPN 21061-17-060
Ex os re Unit ID: EU #2 Lower Level Trail - Greenmay User and Construction Worker
' Now that inhalation on this calculator refers to outdoor inhalation ofvolatiles andparticu/ates, not indoor inhalation associated with vapor intrusion.
" -Note that the EPA has no consensus on reference dose or cancer slope factor values for lead, therefore it is not possible to calculate cancer risk or hazard quotient.
mglkg for residential soil.
Receptor Type: Grecnway user
Lead concentrations are compared to the EPA screening level of 400
7440-66-6
Zinc and Compounds
77
77
77
Cumulative:
8.4E-06
4.9E-04
4.9E-04
4.1E-01
CAS #
Chemical Name:
Ingestion
Concentration
(mg/kg)
Devoid
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)*
Ingestion
Carcinogenic
Risk
Derntal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Dermal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
14.5
14.5
14.5
6.8E-06
1.2E-06
1.6E-11
8.0E-06
5.5E-02
7.6E-03
6.8E-07
6.3E-02
7440-39-3
Barium
958
958
958
9.1E-03
1.3E-06
9.1E-03
7440-41-7
Beryllium and compounds
1.56
1.56
1.56
9.7E-13
9.7E-13
1.5E-03
5.5E-08
1.5E-03
7440-43-9
Cadmium (Diet)
0.284
0.284
0.284
1.3E-13
1.3E-13
5.4E-04
6.0E-05
2.0E-08
6.0E-04
16065-83-1
Chromium(RH, Insoluble Salts
40.2
40.2
40.2
5.1E-05
5.1E-OS
18540-29-9
Clvomimn(VA
0.497
0.497
0.497
3.9E-07
3.0E-11
3.9E-07
3.1E-04
3.5E-09
3.1E-04
7440-48-4
Cobalt
16.5
16.5
16.5
3.9E-11
3.9E-11
1.0E-Ol
1.9E-06
1.0E-01
7440-50-8
Cooper
43.4
43.4
43.4
2.1E-03
2.1E-03
7439-92-1
-Lead and Compounds
18
18
18
GSL**
<SL**
<SL**
7439-96-5
Manganese (Non -diet)
594
594
594
4.7E-02
8.3E-06
4.7E-02
7439-97-6
-Me.-(elementaH
0.12
0.12
0.12
4.5E-04
4.5E-04
7440-02-0
Nickel Soluble Salts
19.2
19.2
19.2
1.3E-12
1.3E-12
1.8E-03
1.5E-07
1.8E-03
7782-49-2
Selenium
3.07
3.07
3.07
1.2E-03
LIE-10
1.2E-03
7440-24-6
Strontium, Stable
125
125
125
4.0E-04
4.0E-04
7440-28-0
Thallium (Soluble Salts)
0.81
0.81
0.81
1.5E-01
1.5E-01
7440-62-2
Vanadium and Compounds
52
52
52
2.0E-02
3.6E-07
2.0E-02

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU #2 Lower Level Creek - Greenway User
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU #2 Lower Level Creek - Greenway User
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
R1
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
El
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
❑
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
❑
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
❑
Output Form 2F
Recreator/Trespasser Soil
0
Output Form 2G Recreator/Tres asser Surface Water
0
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 3D
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Creek - Greenway User
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
❑
Groundwater Use
❑
Non -Residential Worker
Soil
❑
Groundwater Use
❑
Construction Worker
Soil
❑
Recreator/Trespasser
Soil
0
Surface Water
0
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Creek - Greenway User
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (cm2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (cm2)
19652
19652
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0.71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm2)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ET,) (hr/event)
0.67
0.67
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA) (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Creek - Greenway User
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
70
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
52
98th percentile based on trail polling data
Exposure Time (ET) (hr)
2
NA
0.5
98th percentile based on trail polling data
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
0.5
98th percentile based on trail polling data
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
SO
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
364
98th percentile based on trail polling data
Exposure Time (ET) (hr)
2
2
1
98th percentile based on trail polling data
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0985
Water Exposure Time (ET_,) (hr/event)
2
2
1
98th percentile based on trail polling data
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
Unit ID: EU #2 Lower Level Creek - Greenwav User
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from sediment samples collected at the site during the most recent sampling event.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Concentration
(mg/kg)
Notes:
CAS Number
Chemical
For the chemicals highlighted in blue, data entry notes are provided in the
PSRG Table link on the Main Menu
Minimum
Concentration
(Qualifier)
Maximum
Concentration
(Qualifier)
Units
Location of
Maximum
Concentration
on
Detection
Frequency
Range of
Detection Limits
Concentration
Used for
Screening
Background
Value
Screening
Toxicity Value
(Screening
Level) (n/c)
Potential
ARAR/TBC
Value
Potential
ARAR/TBC
Source
COPC
Flag
(YQ�
Rationale for
Selection or
Deletion
2.35
SED4
7440-38-2
Arsenic, Inorganic
mg/kg
24.3
SED-5
7440-39-3
Barium
mg/kg
0.233
SED-5
7440-41-7
Beryllium and compounds
I
mg/kg
63.8
SED4
16065-83-1
Chromium(III), Insoluble
mg/kg
0.67
SED-3
18540-29-9
Chromium(VI)
mg/kg
7.26
SED4
7440-48-4
Cobalt
mg/kg
20.2
SED-3
7440-50-8
Copper
mg/kg
399
SED-5
7439-96-5
Manganese (Non -diet)
mg/kg
0.008
SED4
7439-97-6
Mercury (elemental)
mg/kg
10.5
SED4
7440-02-0
Nickel Soluble Salts
mg kg
0.344
SED-4
7782-49-2
Selenium
mg kg
30.7
SED4
7440-24-6
Strontium, Stable
Inag
North Carolina DED Risk Calculator

osure Point Concentrations
Lion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
Unit ID: EU #2 Lower Level Creek - Greenwav User
Surface Water Exuosure Point Concentration Table
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations detected in surface water samples over the last 5 years of sampling.
NOTE: If the chemical list is changed from a prior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Concentration
(ug/L)
Notes:
CAS Number
Chemical
Minimum
Concentration
(Qualifier)
Maximum
Concentration
(Qualifier)
Units
Location of
Maximum
Concentration
Detection
Frequency
Range of
Detection
Limits
Concentration
Used for
Screening
Background
Value
Screening
Toxicity ValueARAR/TBC
(Screening
Level) (n/c)
Potential
Value
Potential
ARAR/'I'BC
Source
COPC
Flag
(Y/N)
Rationale for
Selection or
Deletion
0.45
SW-3
7440-38-2
Arsenic, Inorganic
ug/L
32.1
SW-21
7440-39-3
Barium
ug/L
0.73
SW-21
16065-83-1
Chrornium(III), Insoluble Salts
ug/L
0.36
SW-21
7440484
Cobalt
ug/L
3.2
SW-21
7440-50-8
Copper
ug/L
37.4
SW-3
7439-96-5
Manganese (Non -diet)
ug/L
0.62
SW-21
7440-02-0
Nickel Soluble Salts
ug/L
0.12
SW-5
778249-2
Selenium
ug/L
110
SW-3 and SW-4
7440-24-6
Strontium, Stable
ug/L
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Creek - Greenway User
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Non -Residential Worker
Soil
NC
NC
NC
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
NC
NC
NC
Recreator/Trespasser
Soil
1.8E-06
9.1E-02
NO
Surface Water*
3.2E-07
1.7E-02
NO
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

DEQ Risk Calculator - Direct Contact
- Recreator/Tres a er Soil
s
Version Date: June 2021
Basis: May 2021 EPA RSL Table
ko
Site ID: BPN 21061-17-060
Ex os re Unit ID: EU #2 Lower Level Creek - Greenwa User
' Now that inhalation on this calculator refers to outdoor inhalation
ofvolatiles and
particulates, not indoor inhalation associated with vapor intrusion.
" -Note that the EPA has no
consensus on reference dose or cancer slope factor values for lead, therefore it is not possible to calculate cancer risk or
hazard quotient.
Lead concentrations are compared to the EPA screening level of 400
mglkg for residential soil.
Receptor Type: Grecnway
user
7440-24-6
Strontium, Stable
30.7
30.7
30.7
9.7E-05
9.7E-OS
Cumulative:
1.8E-06
9.1E-02
CAS #
Chemical Name:
Ingestion
Concentration
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)*
Ingestion
Carcinogenic
Risk
Derntal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Dermal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
2.35
2.35
2.35
l.1F1116
2.OEA7
2.6E-12
1.3E-06
8.9E-03
1.2E-03
1.1E-07
1.0E-02
7440-39-3
Barium
24.3
24.3
24.3
2.3E-04
3.4E-08
2.3E-04
7440-41-7
Beryllium and compounds
0.233
0.233
0.233
1.5E-13
1.5E-13
2.2E-04
8.2E-09
2.2E-04
16065-83-1
ChromiumHIp, Insoluble Salts
63.8
63.8
63.8
8.1E-OS
8.1E-OS
18540-29-9
Clvomium(VI)
0.67
0.67
0.67
5.3E-07
4.1E-11
5.3E-07
4.2E-04
4.7E-09
4.2E-04
7440-48-4
Cobalt
7.26
7.26
7.26
1.7E-11
1.7E-11
4.6E-02
8.5E-07
4.6E-02
7440-50-8
Cooper
20.2
20.2
20.2
9.6E-04
9.6E-04
7439-96-5
Manganese (Non -diet)
399
399
399
3.2E-02
5.6E-06
3.2E-02
7439-97-6
-Mercury (elemental)
0.008
0.008
0.008
3.0E-OS
3.0E-OS
7440-02-0
Nickel Soluble Salts
10.5
10.5
10.5
7.1E-13
7.1E-13
1.0E-03
8.2E-08
1.0E-03
7782-49-2
Selenium
0.344
0.344
0.344
1.3E-04
1.2E-11
1.3E-04

DEQ Risk Calculator - Direct Contact - Recreator/Tres asser Surface Water
Version Date: June 2021
Basis: May 2021 EPA RSL Table
igloo"
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #2 Lower Level Creek - Greenway User
Receptor Type: Greenway
user
1.7E-02
Calculated
Ingestion
Dermal
Ingestion
Dermal Contact
Calculated
Ingestion
Dermal
Non -
CAS #
Chemical Name:
Concentration
Concentration
Carcinogenic
Carcinogenic
Carcinogenic
Hazard
Contact
Carcinogenic(ug/L)
(ug/L)
Risk
Risk
Risk
Quotient
Hazard
HazardQuotient
Quotient
7440-38-2
Arsenic, Inorganic
0.45
0.45
2.7E-07
4.5E-08
3.2E-07
1.8E-03
3.7E-04
2.2E-03
7440-39-3
Barium
32.1
32.1
2.0E-04
5.6E-04
7.6E-04
16065-83-1
Chromium(III), Insoluble Salts
0.73
0.73
6.0E-07
9.2E-06
9.8E-06
7440-45-4
Cobalt
0.36
0.36
1.5E-03
1.2E-04
1.6E-03
7440-50-8
Copper
3.2
3.2
9.8E-05
2.0E-05
1.2E-04
7439-96-5
Manganese (Non -diet)
37.4
37.4
1.9E-03
9.5E-03
1.1E-02
7440-02-0
Nickel Soluble Salts
0.62
0.62
3.8E-05
3.8E-05
7.6E-05
7782-49-2
Selenium
0.12
0.12
2.9E-05
5.9E-06
3.5E-05
7440-24-6
Strontium, Stable
110
110
2.3E-04
4.5E-05
2.7E-04
NMh Carding CEO Risk CalcNatw

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU #3 Embankment - Resident, Non -Residential Worker, and Greenway
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU #3 Embankment - Resident, Non -Residential Worker, and Greenway User
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
0
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
El
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
❑
Output Form 2F
Recreator/Trespasser Soil
0
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 31)
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Resident, Non -Residential Worker, and Gr
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
0
Groundwater Use
❑
Non -Residential Worker
Soil
0
Groundwater Use
❑
Construction Worker
Soil
❑
Recreator/Trespasser
Soil
0
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Resident, Non -Residential Worker, and Greenway User
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
EL
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (cm2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (cm2)
19652
19
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0,71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETe e �) (hr/event)
0.67
0.67
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SAj (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Resident, Non -Residential Worker, and Greenway User
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
70
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
52
Based on 98 %percentile of trail users
Exposure Time (ET) (hr)
2
NA
0.5
Based on 98 %percentile of trail users
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
2
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
364
Based on 98%percentile of trail users
Exposure Time (ET) (hr)
2
2
1
Based on 98%percentile of trail users
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0985
Water Exposure Time (ET_„) (hr/event)
2
2
2
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
osure Unit ID: EU #3 Embankment -Resident, Non -Residential Worker, and Greenwav User
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from samples collected from shallow (0-2 ft) soil within the exposure unit.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Concentration
(mg/kg)
Notes:
CAS Number
Chemical
For the chemicals highlighted in blue, data entry notes are provided in the
PSRG Table link on the Main Menu
Minimum
Concentration
(Qualifier)
Maximum
Concentration
(Qualifier)
Units
Location of
Maximum
Concentration
on
Detection
Frequency
Range of
Detection Limits
Concentration
Used for
Screening
Background
Value
Screening
Toxicity Value
(Screening
Level) (n/c)
Potential
ARAR/TBC
Value
Potential
ARAR/TBC
Source
COPC
Flag
(YQS)
Rationale for
Selection or
Deletion
60.3
HH-10
7440-38-2
Arsenic, Inorganic
mg/kg
3260
HH-11
7440-39-3
Barium
mg/kg
5.9
HH-11
7440-41-7
Beryllium and compounds
mg/kg
0.22
HH-11
7440-43-9
Cadmium (Diet) pr
mg/kg
43.8
Excavation H-2
16065-83-1
Chromium(III), Insoluble Salts
mg/kg
1.4
S-7
18540-29-9
Chromium(VI)
mg/kg
19.1
Excavation H-2
7440-48-4
Cobalt
mg/kg
59.2
Excavation H-2
7440-50-8
Copper
mg/kg
412
Excavation H-1
7439-96-5
Manganese (Non -diet)
mg/kg
0.43
HH-11
7439-97-6
Mercury (elemental)
mg/kg
23.5
HH-11
7440-02-0
Nickel Soluble Salts
mg/kg
9.05
HH-11
7782-49-2
Selenium
mag
269
HH-10
7440-24-6
Strontium, Stable
mg/kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Resident, Non -Residential Worker, and Greenway User
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
9.4E-05
3.1E+00
YES
Groundwater Use*
NC
NC
NC
Non -Residential Worker
Soil
2.0E-05
2.2E-01
NO
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
NC
NC
NC
Recreator/Trespasser
Soil
3.4E-05
4.6E-01
NO
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

Date: Jane 2021
May 2021 EPA RSL Table
* - Note that inhalation on this calculator refers to outdoor inhalation ofvotarites andparncutates, not indoor inhalation associated with vapor intrusion.
** - Note that the EPA has no consensus on reference dose or cancer slope factor values for lead, therefore it is not possihle to calculate cancer riskor hazard quotient. Lead concentrations are compared to the EPA screening
level of 400 mg1kg for residential soil.
CAS #
Chentical Name:
Ingestion
Concentration
(WAg)
Dermal
Concentration
(mg/kg)
Inhalation
Concentration
(WA9)*
Ingestion
Carcinogenic
Risk
Demal
Carcinogenic
Risk
Inhalation
Carcinogen
Risk*
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Detmal
Hazard
Quotient
Inhalation
Hazard
Quotient*
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
60.3
60.3
60.3
7.8E-05
1.1E-05
1.6E-09
8.9E-05
1.5E+00
1.8E-01
6.5E-05
1.7E+00
7440-39-3
Barium
3260
3260
3260
2.1E-01
1.1E-04
2.1E-01
744041-7
Beryllium and compounds
5.9
5.9
5.9
8.5E-11
8.5E-11
3.8E-02
4.8E-06
3.8E-02
744043-9
Cadmium(Diet)
0.22
0.22
0.22
2.4E-12
2.4E-12
2.8E-03
2.7E-04
3.6E-07
3.1E-03
16065-83-1
Chromium([@, Insoluble Salts
43.8
43.8
43.8
3.7E-04
3.7E-04
18540-29-9
Chromium(VI)
1.4
1.4
1.4
4.6E-06
2.0E-09
4.6E-06
6.0E-03
2.3E-07
6.0E-03
7440484
Cobalt
19.1
19.1
19.1
1.0E-09
1.0E-09
SAE-01
5.1E-05
8.1E-01
7440-50-8
Copper
59.2
59.2
59.2
1.9E-02
1.9E-02
7439-96-5
Manganese(Non-diet)412
412
412
2.2E-01
1.3E-04
2.2E-01
7439-97-6
-Mercury(elementap
0.43
0.43
0.43
3.7E-02
3.7E-02
7440-02-0
Nickel Soluble Salts
23.5
23.5
23.5
3.7E-11
3.7E-11
1.5E-02
4.2E-06
1.5E-02
778249-2
Selenium
9.05
9.05
9.05
2.3E-02
7.3E-09
2.3E-02
7440-24-6 1 Strontium. Stable 1 269 1 269 1 269
I I I 5.7E-03 I I I 5.7E-03 I
Cumulative: 9.4E-OS 3.1E+00
Nona Carolina DEQ nlak Calculator

DEQ Risk Calculator - Direct
Contact - Non -Residential Worker Soil
s
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Ex os re Unit ID: EU #3 Embankment -Resident, Non -Residential
Worker, and GErreen-ay
U
' Now that inhalation on
this calculator refers to outdoor inhalation ofvolatiles and
particulates, not indoor inhalation associated with vapor intrusion.
" -Note that the EPA has
no consensus on reference dose or
cancer slope factor values
for lead, therefore it is not possible to calculate cancer risk or
hazard quotient.
Lead concentrations are compared to the EPA screening level of 800
mglkg for commerciallinduarial soil.
7440-24-6
Strontium, Stable
269
269
269
3.8E-04
3.8E-04
Cumulative:
2.0E-05
2.2E-01
CAS#
Chemical Name:
Ingestion
Concentration
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)'
Ingestion
Carcinogenic
Risk
Dermal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Dermal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
60.3
60.3
60.3
1.7E-OS
3.5E-06
3.6E-]0
2.0E-05
1.0E-01
2.2E-02
1.5E-05
1.3E-01
7440-39-3
Barium
3260
3260
3260
1.4E-02
2.5E-05
1.4E-02
7440-41-7
Beryllium and compounds
5.9
5.9
5.9
1.9E-11
1.9E-11
2.5E-03
LIE-06
2.5E-03
7440-43-9
Cadmium (Diet)
0.22
0.22
0.22
5.4E-13
5.4E-13
1.9E-04
3.2E-05
8.5E-08
2.2E-04
16065-83-1
Chmium(Rp, Insoluble Salts
ro
43.8
43.8
43.8
2.5E-OS
2.5E-OS
18540-29-9
Clvomium(VI)
1.4
1.4
1.4
2.1E-07
1.6E-]0
2.1E-07
4.0E-04
5.4E-08
4.0E-04
7440-48-4
Cobalt
19.1
19.1
19.1
2.4E-]0
2.4E-10
5.5E-02
1.2E-OS
5.5E-02
7440-50-8
Cooper
59.2
59.2
59.2
1.3E-03
1.3E-03
7439-96-5
Manganese (Non -diet)
412
412
412
1.5E-02
3.2E-OS
1.5E-02
7439-97-6
-Meroury (elementaD
0.43
0.43
0.43
8.9E-03
8.9E-03
7440-02-0
Nickel Soluble Salts
23.5
23.5
23.5
8.4E-12
8.4E-12
1.0E-03
1.0E-06
1.0E-03
7782-49-2
Selenium
9.05
9.05
9.05
1.5E-03
1.7E-09
1.5E-03

DEQ Risk Calculator - Direct Contact - Recreator/Tres a er Soil
Version Date: June 2021
Basis: May 2021 EPA RSL Table
s
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Resident, Non -Residential Worker, and Greenwa
Use
' Now that inhalation on this calculator refers to outdoor inhalation ofvolatiles andparticu/ates, not indoor inhalation associated with vapor intrusion.
" - Note that the EPA has no consensus on reference dose or cancer slope factor values for lead, therefore it is not possible to calculate cancer risk or hazard quotient.
mglkg for residential soil.
Receptor Type: Greenway User
Lead concentrations are compared to the EPA screening level of 400
Cumulative:
4.6E-01
CAS #
Chemical Name:
Ingestion
Concentration
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)'
Ingestion
Carcinogenic
Risk
Derntal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Dermal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
60.3
60.3
60.3
2.8E-05
5.1E-06
6.7E-11
3.3E-05
2.3E-01
3.2E-02
2.8E-06
2.6E-01
7440-39-3
Barium
3260
3260
3260
3.1E-02
4.6E-06
3.1E-02
7440-41-7
Beryllium and compounds
5.9
5.9
5.9
3.7E-12
3.7E-12
5.6E-03
2.1E-07
5.6E-03
7440-43-9
Cadmium (Diet)
0.22
0.22
0.22
1.0E-13
1.0E-13
4.2E-04
4.6E-05
1.5E-08
4.6E-04
16065-83-1
Chromium(RH, Insoluble Salts
43.8
43.8
43.8
5.5E-05
5.5E-05
18540-29-9
Clvomium(VI)
1.4
1.4
1.4
1.1E-06
8.5E-11
1.1E-06
8.9E-04
9.8E-09
8.9E-04
7440-48-4
Cobalt
19.1
19.1
19.1
4.5E-11
4.5E-11
1.2E-01
2.2E-06
1.2E-01
7440-50-8
Cooper
59.2
59.2
59.2
2.8E-03
2.8E-03
7439-96-5
Manganese (Non -diet)
412
412
412
3.3E-02
5.8E-06
3.3E-02
7439-97-6
-Me.-(elemen(elemental)0.43
0.43
0.43
1.6E-03
1.6E-03
7440-02-0
Nickel Soluble Salts
23.5
23.5
23.5
1.6E-12
1.6E-12
2.2E-03
1.8E-07
2.2E-03
7782-49-2
7440-24-6
Selenium
Strontium, Stable
9.05
269
9.05
269
9.05
269
3.4E-03
8.5E-04
3.2E-10
3.4E-03
8.5E-04

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU #3 Embankment - Construction Worker
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU #3 Embankment - Construction Worker
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
❑
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
❑
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
El
Output Form 2F
Recreator/Trespasser Soil
❑
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 3D
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Construction Worker
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
❑
Groundwater Use
❑
Non -Residential Worker
Soil
❑
Groundwater Use
❑
Construction Worker
Soil
0
Recreator/Trespasser
Soil
❑
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Construction Worker
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (Cm 2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (Cm 2)
19652
19652
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0.71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
�L&
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA) (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Construction Worker
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
52
Based on 98 %percentile of trail users
Exposure Time (ET) (hr)
2
NA
0.5
Based on 98 %percentile of trail users
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
2
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
364
Based on 98 % percentile of trail users
Exposure Time (ET) (hr)
2
2
1
Based on 98 %percentile of trail users
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0985
Water Exposure Time (ET_„) (hr/event)
2
2
2
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
Unit ID: EU #3 Embankment - Construction Worker
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from all samples collected within the exposure unit.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Concentration
(mg/kg)
Notes:
CAS Number
Chemical
For the chemicals highlighted in blue, data entry notes are provided in the
PSRG Table link on the Main Menu
Minimum
Concentration
(Qualifier)
Maximum
Concentration
(Qualifier)
Units
Location of
Maximum
Concentration
on
Detection
Frequency
Range of
Detection Limits
Concentration
Used for
Screening
Background
Value
Screening
Toxicity Value
(Screening
Level) (n/c)
Potential
ARAR/TBC
Value
Potential
ARAR/TBC
Source
COPC
Flag
(YQ�
Rationale for
Selection or
Deletion
60.3
HH-10
7440-38-2
Arsenic, Inorganic
mg/kg
3260
HH-11
7440-39-3
Barium
mg/kg
5.9
HH-11
7440-41-7
Beryllium and compounds
mg/kg
0.22
HH-11
7440-43-9
Cadmium (Diet) pr
mg/kg
43.8
Excavation H-2
16065-83-1
Chromium(IIl), Insoluble Salts
mg/kg
1.4
S-7
18540-29-9
Chromium(VI)
mg/kg
20.8
Excavation H-4
7440-48-4
Cobalt
mg/kg
59.2
Excavation H-2
7440-50-8
Copper
mg/kg
1480
Excavation H-4
7439-96-5
Manganese (Non -diet)
mg/kg
0.43
HH-11
7439-97-6
Mercury (elemental)
mg/kg
23.5
HH-11
7440-02-0
Nickel Soluble Salts
mg/kg
9.05
HH-11
7782-49-2
Selenium
mag
269
HH-10
7440-24-6
Strontium, Stable
mg/kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #3 Embankment - Construction Worker
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Non -Residential Worker
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Construction Worker
Soil
4.4E-06
8.8E+00
YES
Recreator/Trespasser
Soil
NC
NC
NC
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU#1 - Resident & Non -Residential Worker excluding Background
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU#1 - Resident & Non -Residential Worker excluding Background
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
0
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
El
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
❑
Output Form 2F
Recreator/Trespasser Soil
❑
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 31)
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#1 - Resident & Non -Residential Worker excluding Backgrour
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
0
Groundwater Use
❑
Non -Residential Worker
Soil
0
Groundwater Use
❑
Construction Worker
Soil
❑
Recreator/Trespasser
Soil
❑
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#1 - Resident & Non -Residential Worker excluding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
EL
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) Orr)
24
24
Skin Surface Area - Soil Exposure (SA) (cm2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (cm2)
19652
19
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0,71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (he)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) Orr)
8
8
Skin Surface Area - Soil Exposure (SAj (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#1 - Resident & Non -Residential Worker excluding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
195
Exposure Time (ET) (hr)
2
NA
2
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IIiW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
2
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
195
Exposure Time (ET) (hr)
2
2
2
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IIiW) (I/hr)
0.0985
0.071
0.0955
Water Exposure Time (ET_,) (hr/event)
2
2
2
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
Unit ID: EU#1- Resident & Non -Residential Worker
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from shallow samples (0-2 ft) collected within the exposure unit with background concentrations removed.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Chemical
Minimum
Maximum
Location of
Concentration
Screening
Potential
Potential
COPC
Rationale for
Concentration
Notes:
CAS Number
Concentration
Concentration
Units
Maximum
Detection
Range of
Used for
Background
Toxicity Value
ARAR/TBC
ARAR/TBC
Flag
Selection or
(mg/kg)
For the chemicals highlighted in blue, data entry notes are provided in the
(Qualifier)
(Qualifier)
on
Concentration
Frequency
Detection Limits
Screening
Value
(Screening
Value
Source
(Y/N)
Deletion
PSRG Table link on the Main Menu
Level) (n/c)
14
S-4
7440-38-2
Arsenic, Inorganic
mg/kg
200
HH-3
7440-39-3
Barium
mg/kg
1.3
HH-3
744 - -
I Beryllium and compounds
I
mg/kg
1.5
S-4
7440-43-9
Cadmium (Diet)
mg/kg
180
MW-7
7440-50-8
Copper
mg/kg
1500
S-4
7439-96-5
Manganese (Non -diet)
mg/kg
43
S-4
7440-02-0
Nickel Soluble Salts
mg/kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#1 - Resident & Non -Residential Worker excluding Background
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
2.1E-05
1.3E+00
YES
Groundwater Use*
NC
NC
NC
Non -Residential Worker
Soil
4.7E-06
9.1E-02
NO
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
NC
NC
NC
Recreator/Trespasser
Soil
NC
NC
NC
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

Date: Jane 2021
May 2021 EPA RSL Table
* - Note that inhalation on this calculator refers to outdoor inhalation ofvotarites andparncutates, not indoor inhalation associated with vapor intrusion.
** - Note that the EPA has no consensus on reference dose or cancer slope factor values for lead, therefore it is not possihle to calculate cancer riskor hazard quotient. Lead concentrations are compared to the EPA screening
level of 400 mg1kg for residential soil.
CAS #
Chentical Name:
Ingestion
Concentration
(WAg)
Dermal
Concentration
(mg/kg)
Inhalation
Concentration
(WA9)*
Ingestion
Carcinogenic
Risk
Demal
Carcinogenic
Risk
Inhalation
Carcinogen
Risk*
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Detmal
Hazard
Quotient
Inhalation
Hazard
Quotient*
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
14
14
14
1.8E-05
2.5E-06
3.6E-10
2.1E-05
3.6E-01
4.2E-02
1.5E-05
4.0E-01
7440-39-3
Barium
200
200
200
1.3E-02
6.5E-06
1.3E-02
744041-7
Beryllium and compounds
1.3
1.3
1.3
1.9E-11
1.9E-11
8.3E-03
1.1E-06
8.3E-03
744043-9
Cadmium(Diet)
1.5
1.5
1.5
1.6E-11
1.6E-11
1.9E-02
1.8E-03
2.4E-06
2.1E-02
7440101
Copper
180
180
180
5.8E-02
5.8E-02
39 74-96-5
Manganese(Non-diet)
1500
1500
1500
8.0E-Ol
4.8E-04
8.0E-01
7440-02-0
1 Nickel Soluble Salts
43
43
43
6.7E-11
6.7E-11
I 2.7E-02
7.7E-06
I 2.7E-02
Cumulative: 2.1E-OS 1.3E+00
Nona Carolina DEQ nlak Calculator

DEQ Risk Calculator - Direct Contact - Non -Residential Worker Soil
s
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
am
Exposure Unit ID: EU#1 - Resident & Non -Residential Worker excluding Background
' Now that inhalation on this calculator
refers to outdoor inhalation ofvolatiles andparticulates,
not indoor inhalation associated
with vapor intrusion.
" - Note that the EPA has no consensus on reference dose or cancer slope factor values
for lead, therefore it is not possible to calculate cancer risk or
hazard quotient.
Lead concentrations are compared to the EPA screening level of 800
mgag for commerciallindusMal sOd
Cumulative:
4.7E-06
9.1E-02
CAS#
Chemical Name:
Ingestion
Concentration
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)'
Ingestion
Carcinogenic
Risk
Dermal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Dermal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
14
14
14
3.9E-06
8.2E-07
8.3E-11
4.7E-06
2.4E-02
5.1E-03
3.6E-06
2.9E-02
7440-39-3
Barium
200
200
200
8.6E-04
1.5E-06
8.6E-04
7440-41-7
Beryllium and compounds
1.3
1.3
1.3
4.3E-12
4.3E-12
5.6E-04
2.5E-07
5.6E-04
7440-43-9
Cadmium (Diet)
1.5
1.5
1.5
3.7E-12
3.7E-12
1.3E-03
2.2E-04
5.8E-07
1.5E-03
7440-50-8
Cooper
180
180
180
3.9E-03
3.9E-03
7439-96-5
Manganese (Non -diet)
1500
1500
1500
5.4E-02
1.2E-04
5.4E-02
7440-02-0
Nickel Soluble Salts
43
43
43
1.5E-11
1.5E-1 l
1.8E-03
1.8E-06
1.8E-03

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU #1 - Construction Worker excluding Background
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU #1 - Construction Worker excluding Background
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
❑
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
❑
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
El
Output Form 2F
Recreator/Trespasser Soil
❑
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 3D
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 - Construction Worker excluding Background
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
❑
Groundwater Use
❑
Non -Residential Worker
Soil
❑
Groundwater Use
❑
Construction Worker
Soil
0
Recreator/Trespasser
Soil
❑
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 -Construction Worker excluding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (CM 2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (CM 2)
19652
19652
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0.71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm2)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
�L&
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA) (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 -Construction Worker excluding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
195
Exposure Time (ET) (hr)
2
NA
2
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
2
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
195
Exposure Time (ET) (hr)
2
2
2
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0955
Water Exposure Time (ET_,) (hr/event)
2
2
2
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
Unit ID: EU #1 - Construction Worker
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from samples collected between 0 to 10 ft within the exposure unit, excluding background levels.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Concentration
(mg/kg)
Notes:
CAS Number
Chemical
For the chemicals highlighted in blue, data entry notes are provided in the
PSRG Table link on the Main Menu
Minimum
Concentration
(Qualifier)
Maximum
Concentration
(Qualifier)
Units
Location of
Maximum
Concentration
on
Detection
Frequency
Range of
Detection Limits
Concentration
Used for
Screening
Background
Value
Screening
Toxicity Value
(Screening
Level) (n/c)
Potential
ARAR/TBC
Value
Potential
ARAR/TBC
Source
COPC
Flag
(Y/N)
Rationale for
Selection or
Deletion
95.9
GP-5
7440-38-2
Arsenic, Inorganic
mg/kg
3200
S-6
7440-39-3
Barium
mg/kg
6.99
GP-5
7440-41-7
Beryllium and compounds
mg/kg
1.5
S-4
7440-43-9
Cadmium (Diet)
mg/kg
180
MW-7
7440-50-8
Copper
mg/kg
1500
S-4
7439-96-5
Manganese (Non -diet)
mg/kg
1
GP-6
7439-97-6
Mercury (elemental)
mg/kg
43
S-4
7440-02-0
Nickel Soluble Salts
mg/kg
13
GP-5
7782-49-2
Selenium
mg kg
325
GP-5
7440-24-6
Strontium, Stable
mg/kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU #1 - Construction Worker excluding Background
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Non -Residential Worker
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Construction Worker
Soil
5.4E-06
1.1E+01
YES
Recreator/Trespasser
Soil
NC
NC
NC
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

DEQ Risk Calculator - Direct Contact-
Construction Worker Soil
t
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Ex os re Unit ID: EU #1 - Construction Worker excluding Background
' - Note that inhalation on this calculator
refers to outdoor inhalation ofvolaudes and particulates,
not
indoor inhalation associated with
vapor intrusion.
" - Now that the EPA has no consensus on reference dose or cancer slope factor valuesfor lead, therefore it is not possible to calculate cancer risk or hazard quotient Lead concentrations are compared
to the EPA screening level of800
mglkgfor commerciallindustrial soil.
7440-24-6
Strontium, Stable
325
325
325
4.8E-04
4.8E-04
Cumulative:
5.4E-06
1.1E+01
CAS #
Chemical Name:
Ingestion
Concentration
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)*
Ingestion
Carcinogenic
Risk
Demtal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Rink
Ingestion
Hazard
Quotient
Demtal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
95.9
95.9
95.9
3.5E-06
5.6E-07
1JF1116
5.3E-06
5.7E-01
9.1E-02
1.4E+00
2.1E+00
7440-39-3
Barium
3200
3200
3200
4.7E-02
1.4E-Ol
1.9E-01
7440-41-7
Beryllium and compounds
6.99
6.99
6.99
5.2E-08
5.2E-08
4.1E-03
7.9E-02
8.3E-02
7440-43-9
Cadmium (Diet)
1.5
1.5
1.5
8.3E-09
8.3E-09
8.8E-03
LIE-03
3.4E-02
4.4E-02
7440-50-8
Copper
180
180
180
5.3E-02
5.3E-02
7439-96-5
Manganese (Non -diet)
1500
1500
1500
1.8E-01
6.7E+00
6.9E+00
7439-97-6
_Mercury (elementaD
11
11
11
1.1E+00
1.1E+00
7440-02-0
Nickel Soluble Salts
43
43
43
3.4E-08
3.4E-08
6.3E-03
4.8E-02
5.5E-02
7782-49-2
Selenium
13
13
13
7.7E-03
1.5E-04
7.8E-03

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU#2 Trail - Greenway User & Construction Worker excluding Backgr
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU#2 Trail - Greenway User & Construction Worker excluding Background
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
❑
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
❑
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
El
Output Form 2F
Recreator/Trespasser Soil
0
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 31)
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#2 Trail - Greenway User & Construction Worker excluding F
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
❑
Groundwater Use
❑
Non -Residential Worker
Soil
❑
Groundwater Use
❑
Construction Worker
Soil
0
Recreator/Trespasser
Soil
0
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#2 Trail - Greenway User & Construction Worker excluding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (CM 2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (CM 2)
19652
19652
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0.71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
�L&
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA) (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#2 Trail - Greenway User & Construction Worker excluding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
70
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
52
Based on 98th pecrentile of trail user polling data
Exposure Time (ET) (hr)
2
NA
0.5
Based on 98th pecrentile of trail user polling data
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_„) (hr/event)
2
NA
0.5
Based on 98th pecrentile of trail user polling data
Water Event Frequency (EV) (events/day)
1
NA
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
SO
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
364
Based on 98th pecrentile of trail user polling data
Exposure Time (ET) (hr)
2
2
1
Based on 98th pecrentile of trail user polling data
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0955
Water Exposure Time (ET_,) (hr/event)
2
2
1
Based on 98th pecrentile of trail user polling data
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
osure Unit ID: EU#2 Trail - Greenway User & Construction Worker
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from all soil samples collected within the exposure unit, exlcuding background concentrations
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Chemical
Minimum
Maximum
Location of
Concentration
Screening
Potential
Potential
COPC
Rationale for
Concentration
Notes:
CAS Number
Concentration
Concentration
Units
Maximum
Detection
Range of
Used for
Background
Toxicity Value
ARAR/TBC
ARAR/TBC
Flag
Selection or
(mg/kg)
For the chemicals highlighted in blue, data entry notes are provided in the
(Qualifier)
(Qualifier)
on
Concentration
Frequency
Detection Limits
Screening
Value
(Screening
Value
Source
(YQS)
Deletion
PSRG Table link on the Main Menu
Level) (n/c)
14.5
SED-13
7440-38-2
Arsenic, Inorganic
mg/kg
958
SED-13
7440-39-3
Barium
mg/kg
1.056
SED-13
7440-41-7
Beryllium and compounds
m
37
SED-13
2-4-
772
Selenium
mgk
125
SED-13
7440-24-6
Strontium, Stable
mWkg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#2 Trail - Greenway User & Construction Worker excluding Background
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Non -Residential Worker
Soil
NC
NC
NC
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
8.1E-07
3.9E-01
NO
Recreator/Trespasser
Soil
8.0E-06
7.5E-02
NO
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

DEQ Risk Calculator - Direct Contact-
Construction Worker Soil
t
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Ex os re UnitlD: EU#2 Trail - Greenwa
User& Construction
Worker excludin Back round
' - Note that inhalation on this calculator
refers to outdoor inhalation gfvolatiles and particulates,
not
indoor inhalation associated with vapor intrusion.
" - Now that the EPA has no consensus on reference dose or cancer slope factor values for lead, therefore it is not possible to calculate cancer risk or hazard quotient Lead concentrations are compared
to the EPA screening level of800
mglkgfor commerciallindustrial soil.
7440-24-6
Strontium, Stable
125
125
125
1.8E-04
1.8E-04
Cumulative:
8.1E-07
3.9E-01
Calculated
Ingestion
Derntal
Inhalation
Ingestion
Demtal
Inhalation
Calculated
Ingestion
Demtal
Inhalation
Non -
CAS #
Chemical Name:
Concentration
Concentration
Concentration
Carcinogenic
Carcinogenic
Carcinogenic
Carcinogenic
Hazard
Hazard
Hazard
Carcinogenic
(mg/kg)
(mg/kg)
(mg/kg)*
Risk
Risk
Risk
Rink
Quotient
Quotient
Quotient
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
14.5
14.5
14.5
5.3E-07
8.4E-08
1.9E-07
8.0E-07
8.5E-02
1.4E-02
2.2E-01
3.2E-01
7440-39-3
Barium
958
958
958
1.4E-02
4.3E-02
5.7E-02
7440-41-7
Beryllium and compounds
1.56
1.56
1.56
1.2E-08
1.2E-08
9.2E-04
1.8E-02
1.8E-02
7782-49-2
Selenium
3.07
3.07
3.07
1.8E-03
3.4E-OS
1.8E-03

DEQ Risk Calculator - Direct Contact - Recreator/Tres a er
Soil
s
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Ex os re Unit ID: EU#2 Trail - Greennay
User & Construction Worker excludin
Back round
' Now that inhalation on this calculator
refers to outdoor inhalation
ofvolatiles andparticu/ates, not indoor inhalation associated with vapor intrusion.
" - Note that the EPA has no consensus on reference dose or
cancer slope factor values for lead, therefore it is not possible to calculate cancer risk or
hazard quotient.
Lead concentrations are compared to the EPA screening level of 400
mglkg for residential soil.
Receptor Type: Grecnway user
7440-24-6
Strontium, Stable
125
125
125
4.0E-04
4.0E-04
Cumulative:
8.0E-06
7.5E-02
Calculated
Ingestion
Derntal
Inhalation
Ingestion
Derntal
Inhalation
Calculated
Ingestion
Dermal
Inhalation
Non -
CAS #
Chemical Name:
Concentration
Concentration
Concentration
Carcinogenic
Carcinogenic
Carcinogenic
Carcinogenic
Hazard
Hazard
Hazard
Carcinogenic
(mg/kg)
(mg/kg)
(mg/kg)*
Risk
Risk
Risk
Risk
Quotient
Quotient
Quotient
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
14.5
14.5
14.5
6.8E-06
1.2E-06
1.6E-11
8.0E-06
5.5E-02
7.6E-03
6.8E-07
6.3E-02
7440-39-3
Barium
958
958
958
9.1E-03
1.3E-06
9.1E-03
7440-41-7
Beryllium and compounds
1.56
1.56
1.56
9.7E-13
9.7E-13
1.5E-03
5.5E-08
1.5E-03
7782-49-2
Selenium
3.07
3.07
3.07
1.2E-03
LIE-10
1.2E-03

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU#2 Creek - Greenway User exlcuding Background
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU#2 Creek - Greenway User exlcuding Background
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
R1
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
El
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
❑
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
❑
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
❑
Output Form 2F
Recreator/Trespasser Soil
0
Output Form 2G Recreator/Tres asser Surface Water
0
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 3D
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#2 Creek - Greenway User exlcuding Background
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
❑
Groundwater Use
❑
Non -Residential Worker
Soil
❑
Groundwater Use
❑
Construction Worker
Soil
❑
Recreator/Trespasser
Soil
0
Surface Water
0
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#2 Creek - Greenway User exlcuding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (cm2)
6032
6032
Soil Adherence Factor (AF) (mg/cm)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (cm2)
19652
19652
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0.71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm)
19652
19652
Water Ingestion Rate (IRW) (LJd)
0.83
0.83
Water Exposure Time (ET,) (hr/event)
0.67
0.67
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA) (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#2 Creek - Greenway User exlcuding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
70
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
52
Based on 98th percentile tail use polling data
Exposure Time (ET) (hr)
2
NA
0.5
Based on 98th percentile tail use polling data
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_,) (hr/event)
2
NA
0.5
Based on 98th percentile tail use polling data
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
364
Based on 98th percentile tail use polling data
Exposure Time (ET) (hr)
2
2
1
Based on 98th percentile tail use polling data
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0985
Water Exposure Time (ET_,) (hr/event)
2
2
1
Based on 98th percentile tail use polling data
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
osure Unit ID: EU#2 Creek - Greenway User
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from sediment samples collected at the site during the most recent sampling event, excluding background levels.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Chemical
Minimum
Maximum
Location of
Concentration
Screening
Potential
Potential
COPC
Rationale for
Concentration
Notes:
CAS Number
Concentration
Concentration
Units
Maximum
Detection
Range of
Used for
Background
Toxicity Value
ARAR/TBC
ARAR/TBC
Flag
Selection or
(mg/kg)
For the chemicals highlighted in blue, data entry notes are provided in the
(Qualifier)
(Qualifier)
on
Concentration
Frequency
Detection Limits
Screening
Value
(Screening
Value
Source
(YQ�
Deletion
PSRG Table link on the Main Menu
Level) (n/c)
20.2
SED-3
7440-50-8
Copper
mg/kg
0.008
SED4
7439-97-6
Mercury (elemental)
mg/kg
10.5
SED-4
7440-02-0
Nickel Soluble Salts
mg kg
30.7
SED-4
7440-24-6
Strontium, Stable
mg kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#2 Creek - Greenway User extending Background
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Non -Residential Worker
Soil
NC
NC
NC
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
NC
NC
NC
Recreator/Trespasser
Soil
7.1E-13
2.1E-03
NO
Surface Water*
3.2E-07
1.7E-02
NO
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

DEQ Risk Calculator - Direct Contact - Recreator/Tres a er Soil
s
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Ex os re Unit ID: EU#2 Creek - Greenway
User extending Background
' Now that inhalation on this calculator refers to outdoor inhalation ofvolatiles and particulates, not indoor inhalation associated with vapor intrusion.
" -Note that the EPA has no consensus on reference dose or cancer slope factor values
for lead, therefore it is not possible to calculate cancer risk or
hazard quotient.
Lead concentrations are compared to the EPA screening level
of 400
mglkg for residential soil.
Receptor Type: Grecnway user
Cumulative:
7.1E-13
2.1E-03
Calculated
Ingestion
Derntal
Inhalation
Ingestion
Derntal
Inhalation
Calculated
Ingestion
Dermal
Inhalation
Non -
CAS #
Chemical Name:
Concentration
Concentration
Concentration
Carcinogenic
Carcinogenic
Carcinogenic
Carcinogenic
Hazard
Hazard
Hazard
Carcinogenic
(mg/kg)
(mg0rg)
(mg/kg)'
Risk
Risk
Risk
Risk
Quotient
Quotient
Quotient
Hazard
Quotient
7440-50-8
Cooper
20.2
20.2
20.2
9.6E-04
9.6E-04
7439-97-6
—Mercury (elementaD
0.008
0.008
0.008
3.0E-05
3.0E-05
7440-02-0
Nickel Soluble Salts
10.5
10.5
10.5
7.1E-13
7.1E-13
1.0E-03
8.2E-08
1.0E-03
7440-24-6
Strontium, Stable
30.7
30.7
30.7
9.7E-05
9.7E-05

DEQ Risk Calculator - Direct Contact - Recreator/Tres asser Surface Water
Version Date: June 2021
Basis: May 2021 EPA RSL Table
idiom"
Site ID: BPN 21061-17-060
Ex osurc Unit ID: EU#2 Creek- Greenway User extending Background
Receptor Type: Greenway
user
1.7E-02
Calculated
Ingestion
Dermal
Ingestion
Dermal Contact
Calculated
Ingestion
Dermal
Non -
CAS #
Chemical Name:
Concentration
Concentration
Carcinogenic
Carcinogenic
Carcinogenic
Hazard
Contact
Carcinogenic(ug/L)
(ug/L)
Risk
Risk
Risk
Quotient
Hazard
HazardQuotient
Quotient
7440-38-2
Arsenic, Inorganic
0.45
0.45
2.7E-07
4.5E-08
3.2E-07
1.8E-03
3.7E-04
2.2E-03
7440-39-3
Barium
32.1
32.1
2.0E-04
5.6E-04
7.6E-04
16065-83-1
Chromium(III), Insoluble Salts
0.73
0.73
6.0E-07
9.2E-06
9.8E-06
7440-45-4
Cobalt
0.36
0.36
1.5E-03
1.2E-04
1.6E-03
7440-50-8
Copper
3.2
3.2
9.8E-05
2.0E-05
1.2E-04
7439-96-5
Manganese (Non -diet)
37.4
37.4
1.9E-03
9.5E-03
1.1E-02
7440-02-0
Nickel Soluble Salts
0.62
0.62
3.8E-05
3.8E-05
7.6E-05
7782-49-2
Selenium
0.12
0.12
2.9E-05
5.9E-06
3.5E-05
7440-24-6
Strontium, Stable
110
110
2.3E-04
4.5E-05
2.7E-04
NMh Carding CEO Risk CalcNatw

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU#3 - Resident, Non -Residential Worker, & Greenway User excludign
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU#3 -Resident, Non -Residential Worker, & Greenway User excludign Background
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
0
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
El
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
❑
Output Form 2F
Recreator/Trespasser Soil
0
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 31)
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Resident, Non -Residential Worker, & Greenway User exc
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
0
Groundwater Use
❑
Non -Residential Worker
Soil
0
Groundwater Use
❑
Construction Worker
Soil
❑
Recreator/Trespasser
Soil
0
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Resident, Non -Residential Worker, & Greenway User excludign Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
EL
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (Cm 2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (Cm 2)
19652
19
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0,71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SAj (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Resident, Non -Residential Worker, & Greenway User excludign Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
70
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
52
Based on 98 %percentile of trail users
Exposure Time (ET) (hr)
2
NA
0.5
Based on 98 %percentile of trail users
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_,) (hr/event)
2
NA
0.5
Based on 98 % percentile of trail users
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
364
Based on 98%percentile of trail users
Exposure Time (ET) (hr)
2
2
1
Based on 98%percentile of trail users
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
IMF —
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0985
Water Exposure Time (ET_,) (hr/event)
2
2
1
Based on 98 % percentile of trail users
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
osure Unit ID: EU#3 - Resident, Non -Residential Worker, & Greenwav User
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from samples collected from shallow (0-2 ft) soil within the exposure unit, excluding background levels.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Chemical
Minimum
Maximum
Location of
Concentration
Screening
Potential
Potential
COPC
Rationale for
Concentration
Notes:
CAS Number
Concentration
Concentration
Units
Maximum
Detection
Range of
Used for
Background
Toxicity Value
ARAR/TBC
ARAR/TBC
Flag
Selection or
(mg/kg)
For the chemicals highlighted in blue, data entry notes are provided in the
(Qualifier)
(Qualifier)
on
Concentration
Frequency
Detection Limits
Screening
Value
(Screening
Value
Source
(YQS)
Deletion
PSRG Table link on the Main Menu
Level) (n/c)
60.3
HH-10
7440-38-2
Arsenic, Inorganic
mg/kg
3260
HH-11
7440-39-3
Barium
mg/kg
5.9
HH-11
7440-41-7
Beryllium and compounds
I
I
I mg/kg
0.43
HH-11
7439-97-6
--Mercury (elemental)
mg kg
23.5
HH-11
7440-02-0
Nickel Soluble Salts
mg kg
9.05
HH-11
7782-49-2
Selenium
mag
269
HH-10
7440-24-6
Strontium, Stable
mg/kg
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Resident, Non -Residential Worker, & Greenway User excludi n Background
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
8.9E-05
2.1E+00
YES
Groundwater Use*
NC
NC
NC
Non -Residential Worker
Soil
2.0E-05
1.5E-01
NO
Groundwater Use*
NC
NC
NC
Construction Worker
Soil
NC
NC
NC
Recreator/Trespasser
Soil
3.3E-05
3.1E-01
NO
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

Date: Jane 2021
May 2021 EPA RSL Table
* - Note that inhalation on this calculator refers to outdoor inhalation ofvotarites andparncutates, not indoor inhalation associated with vapor intrusion.
** - Note that the EPA has no consensus on reference dose or cancer slope factor values for lead, therefore it is not possihle to calculate cancer riskor hazard quotient. Lead concentrations are compared to the EPA screening
level of 400 mg1kg for residential soil.
CAS #
Chentical Name:
Ingestion
Concentration
(WAg)
Dermal
Concentration
(mg/kg)
Inhalation
Concentration
(WA9)*
Ingestion
Carcinogenic
Risk
Demal
Carcinogenic
Risk
Inhalation
Carcinogen
Risk*
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Detmal
Hazard
Quotient
Inhalation
Hazard
Quotient*
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
60.3
60.3
60.3
7.8E-05
1.1E-05
1.6E-09
8.9E-05
1.5E+00
1.8E-01
6.5E-05
1.7E+00
7440-39-3
Barium
3260
3260
3260
2.1E-01
1.1E-04
2.1E-01
744041-7
Beryllium and compounds
5.9
5.9
5.9
8.5E-11
8.5E-11
3.8E-02
4.8E-06
3.8E-02
7439-97-6
-Mercury(elementap
0.43
0.43
0.43
3.7E-02
3.7E-02
7440-02-0
Nickel Soluble Salts
23.5
23.5
23.5
3.7E-11
3.7E-11
1.5E-02
4.2E-06
1.5E-02
7782-09-2
Selenium
9.05
9.05
9.05
2.3E-02
7.3E-09
2.3E-02
7440-24-6
1 Strontium, Stable
1 269
1 269
1 269
1
5.7E-03
5.7E-03
Cumulative: 8.9E-OS 2.1E+00
Nona Carolina DEQ nlak Calculator

DEQ Risk Calculator - Direct Contact
- Non -Residential Worker Soil
s
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Ex os re Unit ID: EU#3 -Resident, Non -Residential Worker,
& Grunvory User excludi n Back
round
' Now that inhalation on this calculator refers to outdoor inhalation ofvolatiles andparticulates,
not indoor inhalation associated with vapor intrusion.
" - Note that the EPA has no
consensus on reference dose or cancer slope factor values
for lead, therefore it is not possible to calculate cancer risk or
hazard quotient.
Lead concentrations are compared to the EPA screening level of 800
mgag for commerciallindusMal sOd
Cumulative:
2.0E-OS
1.5E-01
CAS#
Chemical Name:
Ingestion
Concentration
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)'
Ingestion
Carcinogenic
Risk
Dermal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Dermal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
60.3
60.3
60.3
1.7E-05
3.5E-06
3.6E-10
2.0E-05
1.0E-01
2.2E-02
1.5E-05
1.3E-01
7440-39-3
Barium
3260
3260
3260
1.4E-02
2.5E-05
1.4E-02
7440-41-7
Beryllium and compounds
5.9
5.9
5.9
1.9E-11
1.9E-11
2.5E-03
LIE-06
2.5E-03
7439-97-6
-Meroury (elemental)
0.43
0.43
0.43
8.9E-03
8.9E-03
7440-02-0
Nickel Soluble Salts
23.5
23.5
23.5
8.4E-12
8.4E-12
1.0E-03
1.0E-06
1.0E-03
7782-49-2
Selenium
9.05
9.05
9.05
1.5E-03
1.7E-09
1.5E-03
7440-24-6
Strontium, Stable
269
269
269
3.8E-04
3.8E-04

DEQ Risk Calculator - Direct Contact
- Recreator/Tres a er
Soil
s
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Resident, Non -Residential Worker, & Greennay User excludi n Back
round
' Now that inhalation on this calculator refers to outdoor inhalation
ofvolatiles andparticu/ates, not indoor inhalation associated with vapor intrusion.
" -Note that the EPA has no
consensus on reference dose or
cancer slope factor values
for lead, therefore it is not possible to calculate cancer risk or
hazard quotient.
Lead concentrations are compared to the EPA screening level
of 400
mglkg for residential soil.
Receptor Type: Grecnway User
Cumulative:
3.3E-05
3.1E-01
CAS #
Chemical Name:
Ingestion
Concentration
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)'
Ingestion
Carcinogenic
Risk
Derntal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Risk
Ingestion
Hazard
Quotient
Dermal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
60.3
60.3
60.3
2.8F1115
S.1E-06
6.7E-11
3.3E-OS
2.3E-0I
3.2E-02
2.8E-06
2.6E-01
7440-39-3
Barium
3260
3260
3260
3.1E-02
4.6E-06
3.1E-02
7440-41-7
Beryllium and compounds
5.9
5.9
5.9
3.7E-12
3.7E-12
5.6E-03
2.1E-07
5.6E-03
7439-97-6
-Mercury (elementaD
0.43
0.43
0.43
1.6E-03
1.6E-03
7440-02-0
Nickel Soluble Salts
23.5
23.5
23.5
1.6E-12
1.6E-12
2.2E-03
1.8E-07
2.2E-03
7782-49-2
Selenium
9.05
9.05
9.05
3.4E-03
3.2E-10
3.4E-03
7440-24-6
Strontium, Stable
269
269
269
8.5E-04
8.5E-04

North Carolina Department of Environmental Quality
Risk Calculator
Version Date:
June 2021
Basis:
May 2021 EPA RSL Table
Site Name:
828 MLK Jr. Blvd Property
Site Address:
828 MLK Jr Blvd, Chapel Hill, Orange County, North Carolina
DEQ Section:
Brownfields Program
Site ID:
BPN 21061-17-060
Exposure Unit ID:
EU#3 - Construction Worker excluding Background
Submittal Date:
Prepared By:
Hart & Hickman, PC
3921 Sunset Ridge Rd, Suite 301, Raleigh, North Carolina
Reviewed By:
North Carolina DEQ Risk Calculator

Table of Contents
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID:
EU#3 - Construction Worker excluding Background
Form No.
Description
Check box
if included
DATA INPUT SHEETS
Input Section 1 - Exposure Pathways & Parameters
Input Form IA
Complete Exposure Pathways
0
Input Form 1B
Exposure Factors and Target Risks
0
Input Form I
Contaminant Migration Parameters
❑
Input Form I
Sample Statistics
❑
Input Section 2 - Exposure Point Concentrations
Input Form 2A
Soil Exposure Point Concentration Table
Input Form 2B
Groundwater Exposure Point Concentration Table
❑
Input Form 2C
Surface Water Exposure Point Concentration Table
❑
Input Form 2D
Soil Gas Exposure Point Concentration Table
❑
Input Form 2E
Indoor Air Exposure Point Concentration Table
❑
DATA OUTPUT SHEETS
Output Section 1 - Summary Output for All Calculators
Output Form lA Risk for Individual Pathways
El
Output Form I
Sitewide Risk
❑
Output Section 2 - Direct Contact Soil and Groundwater Calculators
Output Form 2A
Resident Soil
❑
Output Form 2B
Resident Groundwater Use
❑
Output Form 2C
Non -Residential Worker Soil
❑
Output Form 2D
Non -Residential Worker Groundwater Use
❑
Output Form 2E
Construction Worker Soil
El
Output Form 2F
Recreator/Trespasser Soil
❑
Output Form 2G Recreator/Tres asser Surface Water
❑
Output Section 3 - Vapor Intrusion Calculators
Output Form 3A Resident Groundwater to Indoor Air
❑
Output Form 3B
Resident Soil Gas to Indoor Air
❑
Output Form 3C
Resident Indoor Air
❑
Output Form 3D
Non -Residential Worker Groundwater to Indoor Air
❑
Output Form 3E
Non -Residential Worker Soil Gas to Indoor Air
❑
Output Form 3F
Non -Residential Worker Indoor Air
❑
Output Section 4 - Contaminant Migration Worksheets
Output Form 4A
Soil to Groundwater - Forward Mode
❑
Output Form 4B
Groundwater to Groundwater - Forward Mode
❑
Output Form 4C
Soil to Surface Water - Forward Mode
❑
Output Form 41)
Groundwater to Surface Water - Forward Mode
❑
Output Form 4E
Soil to Groundwater - Backward Mode
❑
Output Form 4F
Groundwater to Groundwater - Backward Mode
❑
Output Form 4G
Soil to Surface Water - Backward Mode
❑
Output Form 4H
Groundwater to Surface Water - Backward Mode
❑
North Carolina DEQ Risk Calculator

Complete Exposure Pathways
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Construction Worker excluding Background
Note: Risk output will only be calculated for complete exposure pathways.
Receptor
Pathway
Check box if
pathway
complete
DIRECT CONTACT SOIL AND WATER PATHWAYS
Resident
Soil
❑
Groundwater Use
❑
Non -Residential Worker
Soil
❑
Groundwater Use
❑
Construction Worker
Soil
0
Recreator/Trespasser
Soil
❑
Surface Water
❑
VAPOR INTRUSION PATHWAYS
Resident
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
Non -Residential Worker
Groundwater to Indoor Air
❑
Soil Gas to Indoor Air
❑
Indoor Air
❑
CONTAMINANT MIGRATION PATHWAYS
Groundwater
Source Soil
❑
Source Groundwater
❑
Surface Water
Source Soil
❑
Source Groundwater
❑
North Carolina DEQ Risk Calculator

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Construction Worker excluding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
General
Target Cancer Risk (individual)
1.0E-06
1.0E-06
Target Cancer Risk (cumulative)
1.0E-04
1.0E-04
Target Hazard Index (individual)
2.0E-01
2.0E-01
Target Hazard Index (cumulative)
1.0E+00
1.0E+00
Residential Child
Lifetime LT ears
70
70
Body Weight (BW) (kg)
15
15
Exposure Duration (ED) (yr)
6
6
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA.) (cm2)
2373
2373
Soil Adherence Factor (AF) (mg/cm2)
0.2
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
200
Skin Surface Area - Water Exposure (SA,) (cm2)
6365
6365
Water Ingestion Rate (IRW) (L/d)
0.78
0.78
Water Exposure Time (ET,) (hr/event)
0.54
0.54
Water Event Frequency (EV) (events/day)
I
1
Residential Adult
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
20
20
Exposure Frequency (EF) (d/yr)
350
350
Exposure Time (ET) (hr)
24
24
Skin Surface Area - Soil Exposure (SA) (CM 2)
6032
6032
Soil Adherence Factor (AF) (mg/cm2)
0.07
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
100
Skin Surface Area - Water Exposure (SAw) (CM 2)
19652
19652
Water Ingestion Rate (IRW) (LJd)
2.5
2.5
Water Exposure Time (ET_,) (hr/event)
0.71
0.71
Water Event Frequency (EV) (events/day)
1
1
Non -Residential Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Exposure Duration (ED) (yr)
25
25
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA.) (cm)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
0.12
0.12
Soil Ingestion Rate (IR) (mg/day)
100
100
Skin Surface Area - Water Exposure (SA,) (cm)
19652
19652
Water Ingestion Rate (IRW) (L/d)
0.83
0.83
Water Exposure Time (ETne �) (hr/event)
0.67
0.67
�L&
Water Event Frequency (EV) (events/day)
1
1
Construction Worker
Lifetime LT ears
70
70
Body Weight (BW) (kg)
80
80
Working Weeks (EW) (wk/yr)
50
50
Exposure Duration (ED) (yr)
1
1
Exposure Frequency (EF) (d/yr)
250
250
Exposure Time (ET) (hr)
8
8
Skin Surface Area - Soil Exposure (SA) (cm2)
3527
3527
Soil Adherence Factor (AF) (mg/cm2)
03
0.3
Soil Ingestion Rate (IR) (mg/day)
330
330
North Carolina DEQ Risk Calwlalor

Exposure Factors and Target Risks
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Construction Worker excluding Background
Exposure Parameter
Default Value
Site Specific
Value
Justification
User Defined Child
Recreator
Trespasser
Lifetime LT ears
70
NA
Averaging Time (AT) (days/yr)
365
NA
365
Body Weight (BW) (kg)
15
NA
15
Exposure Duration 0-2 (ED) (yr)
2
NA
2
Exposure Duration 2-6 (ED) (yr)
4
NA
4
Exposure Frequency (EF) (d/yr)
195
NA
52
Based on 98th percentile of trail use polling data
Exposure Time (ET) (hr)
2
NA
0.5
Based on 98th percentile of trail use polling data
Skin Surface Area -Soil Exposure (SAS (cm)
2373
NA
2373
Soil Adherence Factor (AF) (mg/cmZ)
0.2
NA
0.2
Soil Ingestion Rate (IRS) (mg/day)
200
NA
200
Skin Surface Area -Water Exposure (SA,) (cm)
6365
NA
6365
Water Ingestion Rate (IRW) (I/hr)
0.124
NA
0.124
Water Exposure Time (ET_,) (hr/event)
2
NA
0.5
Based on 98th percentile of trail use polling data
Water Event Frequency (EV) (events/day)
1
NA
1
User Defined Adult
Recreator
Trespasser
Lifetime LT ears
70
70
70
Body Weight (BW) (kg)
80
45
80
Exposure Duration 6-16 (ED) (yr)
10
10
10
Exposure Duration 16-26 (ED) (yr)
10
0
10
Exposure Frequency (EF) (d/yr)
195
90
364
Based on 98th percentile of trail use polling data
Exposure Time (ET) (hr)
2
2
1
Based on 98th percentile of trail use polling data
Skin Surface Area -Soil Exposure (SAS (cm)
6032
6032
6032
Soil Adherence Factor (AF) (mg/cmZ)
0.07
0.2
0.07
Soil Ingestion Rate (IRS) (mg/day)
100
200
100
Skin Surface Area -Water Exposure (SA,) (cm)
19652
19652
19652
Water Ingestion Rate (IRW) (I/hr)
0.0985
0.071
0.0955
Water Exposure Time (ET_,) (hr/event)
2
2
1
Based on 98th percentile of trail use polling data
Water Event Frequency (EV) (events/day)
1
1
1
North Carolina DEQ Risk Calwlalor

osure Point Concentrations
.ion Date: June 2021
s: May 2021 EPA RSL Table
ID: BPN 21061-17-060
Unit ID: EU#3 - Construction Worker
Description of Exposure Point Concentration Selection:
Maximum detected constituent concentrations from all samples collected within the exposure unit, excluding background levels.
NOTE: If the chemical list is chaneed from a urior calculator run, remember to select "See All Chemicals" on the data output sheet or newly added chemicals will not be included in risk calculations
Exposure Point
Chemical
Minimum
Maximum
Location of
Concentration
Screening
Potential
Potential
COPC
Rationale for
Concentration
Notes:
CAS Number
Concentration
Concentration
Units
Maximum
Detection
Range of
Used for
Background
Toxicity Value
ARAR/TBC
ARAR/TBC
Flag
Selection or
(mg/kg)
For the chemicals highlighted in blue, data entry notes are provided in the
(Qualifier)
(Qualifier)
on
Concentration
Frequency
Detection Limits
Screening
Value
(Screening
Value
Source
(YQ�
Deletion
PSRG Table link on the Main Menu
Level) (n/c)
60.3
HH-10
7440-38-2
Arsenic, Inorganic
mg/kg
3260
HH-11
7440-39-3
Barium
mg/kg
5.9
HH-11
7440-41-7
Beryllium and compounds
I
I
mg/kg
1480
Excavation H-4
7439-96-5
Manganese (Non -diet)
mg/kg
0.43
HH-11
7439-97-6
Mercury (elemental)
mg/kg
23.5
HH-11
7440-02-0
Nickel Soluble Salts
mg/kg
9.05
HH-11
7782-49-2
Selenium
mg/kg
269
HH-10
7440-24-6
Strontium, Stable
mag
North Carolina DED Risk Calculator

Risk for Individual Pathways
-FIR
IM
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Construction Worker excluding Background
DIRECT CONTACT SOIL AND WATER CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Non -Residential Worker
Soil
NC
NC
NC
NC
Groundwater Use*
NC
NC
Construction Worker
Soil
3.4E-06
8.5E+00
YES
Recreator/Trespasser
Soil
NC
NC
NC
Surface Water*
NC
NC
NC
VAPOR INTRUSION CALCULATORS
Receptor
Pathway
CarcinogenicHazard
Risk
Index
Risk exceeded?
Resident
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
Non -Residential Worker
Groundwater to Indoor Air
NC
NC
NC
Soil Gas to Indoor Air
NC
NC
NC
Indoor Air
NC
NC
NC
CONTAMINANT
MIGRATION CALCULATORS
Pathway
Source
Target Receptor Concentrations Exceeded?
Groundwater
Source Soil
Exceedence of 2L at Receptor?
NC
Source Groundwater
Exceedence of 2L at Receptor?
NC
Surface Water
Source Soil
Exceedence of 2B at Receptor?
NC
Source Groundwater
Exceedence of 2B at Receptor?
NC
Notes:
1. If lead concentrations were entered in the exposure point concentration tables, see the individual calculator sheets for lead
concentrations in comparison to screening levels. Note that lead is not included in cumulative risk calculations.
2. * = If concentrations in groundwater exceed the NC 2L Standards or IMAC, or concentrations in surface water exceed the
NC 2B Standards, appropriate remediation and/or institutional control measures will be necessary to be eligible for a risk -based
closure.
3. NM = Not Modeled
4. NC = Pathway not calculated
North Carolina DEQ Risk Calculator

DEQ Risk Calculator - Direct Contact-
Construction Worker Soil
t
Version Date: June 2021
Basis: May 2021 EPA RSL Table
Site ID: BPN 21061-17-060
Exposure Unit ID: EU#3 - Construction Worker excluding Background
' - Note that inhalation on this calculator
refers to outdoor inhalation ofvolaudes and particulates,
not
indoor inhalation associated with
vapor intrusion.
" - Now that the EPA has no consensus on reference dose or cancer slope factor valuesfor lead, therefore it is not possible to calculate cancer risk or hazard quotient Lead concentrations are compared
to the EPA screening level of800
mglkgfor cummerciallinduscrial soil.
11
7440-24-6
Strontimn, Stable
269
269
269
4.0E-04
4.0E-04
Cumulative:
3.4E-06
8.5E+00
CAS #
Chemical Name:
Ingestion
Concentrator
(mg/kg)
Derntal
Concentration
(mg/kg)
Inhalation
Concentration
(mg/kg)'
Ingestion
Carcinogenic
Risk
Demtal
Carcinogenic
Risk
Inhalation
Carcinogenic
Risk
Calculated
Carcinogenic
Rink
Ingestion
Hazard
Quotient
Demtal
Hazard
Quotient
Inhalation
Hazard
Quotient
Calculated
Non -
Carcinogenic
Hazard
Quotient
7440-38-2
Arsenic, Inorganic
60.3
60.3
60.3
21F1116
3.5E-07
8.0E-07
3.3E-06
3.6E-01
5.7E-02
9.0E-01
1.3E+00
7440-39-3
Barium
3260
3260
3260
4.8E-02
1.5E-01
1.9E-01
7440-41-7
Beryllium and compounds
5.9
5.9
5.9
4.4E-08
4.4E-08
3.5E-03
6.6E-02
7.0E-02
7439-96-5
Manganese (Non -diet)
1480
1480
1480
1.8E-01
6.6E+00
6.8E+00
7439-97-6
_Mercury (elemental)
0.43
0.43
0.43
4.4E-02
4.4E-02
7440-02-0
Nickel Soluble Salts
23.5
23.5
23.5
1.9E-08
1.9E-08
3.5E-03
2.6E-02
3.0E-02
7782-49-2
Selenimn
9.05
9.05
9.05
5.3E-03
1.0E-04
5.4E-03