HomeMy WebLinkAboutNC0004979_Allen Assessment Work Plan_20141230
Allen Steam Station Ash Basin
Proposed Groundwater
Assessment Work Plan
(Rev.1)
NPDES Permit NC0004979
December 30, 2014
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
Table of Contents
Table of Contents
Table of Contents ......................................................................................................................... i
Executive Summary .............................................................................................................. ES-1
1.0 Introduction .......................................................................................................................... 1
2.0 Site History........................................................................................................................... 4
2.1 Plant Description ...................................................................................................... 4
2.2 Ash Basin Description ............................................................................................... 4
2.3 Regulatory Requirements ......................................................................................... 5
3.0 Receptor Information ............................................................................................................ 8
4.0 Regional Geology and Hydrogeology ................................................................................... 9
5.0 Initial Conceptual Site Model ...............................................................................................11
5.1 Physical Site Characteristics ....................................................................................11
5.1.1 Ash Basin .....................................................................................................12
5.1.2 Ash Landfill ..................................................................................................12
5.1.3 Structural Fills ..............................................................................................13
5.1.4 Ash Storage .................................................................................................13
5.2 Source Characteristics .............................................................................................14
5.3 Hydrogeologic Site Characteristics ..........................................................................16
6.0 Compliance Groundwater Monitoring ..................................................................................19
7.0 Assessment Work Plan .......................................................................................................20
7.1 Subsurface Exploration ............................................................................................21
7.1.1 Ash and Soil Borings ....................................................................................21
7.1.2 Shallow Monitoring Wells .............................................................................24
7.1.3 Deep Monitoring Wells .................................................................................25
7.1.4 Bedrock Monitoring Wells .............................................................................26
7.1.5 Well Completion and Development ..............................................................26
7.1.6 Hydrogeologic Evaluation Testing ................................................................27
7.2 Groundwater Sampling and Analysis .......................................................................28
7.2.1 Existing Compliance and Voluntary Monitoring Wells ...................................29
7.2.2 Onsite Water Supply Wells ...........................................................................29
7.2.3 Speciation of Select Inorganics ....................................................................30
7.3 Surface Water and Seep Sampling ..........................................................................30
7.3.1 Surface Water Samples ...............................................................................30
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
Table of Contents
7.3.2 Seep Samples ..............................................................................................30
7.3.3 Sediment Samples .......................................................................................31
7.4 Field and Sampling Quality Assurance/Quality Control Procedures .........................31
7.4.1 Field Logbooks .............................................................................................31
7.4.2 Field Data Records ......................................................................................32
7.4.3 Sample Identification ....................................................................................32
7.4.4 Field Equipment Calibration .........................................................................32
7.4.5 Sample Custody Requirements ....................................................................33
7.4.6 Quality Assurance and Quality Control Samples ..........................................34
7.4.7 Decontamination Procedures .......................................................................35
7.5 Site Hydrogeologic Conceptual Model .....................................................................36
7.6 Site-Specific Background Concentrations ................................................................36
7.7 Groundwater Fate and Transport Model ..................................................................37
7.7.1 MODFLOW/MT3DMS Model ........................................................................37
7.7.2 Development of Kd Terms ............................................................................38
7.7.3 MODFLOW/MT3DMS Modeling Process .....................................................40
7.7.4 Hydrostratigraphic Layer Development ........................................................41
7.7.5 Domain of Conceptual Groundwater Flow Model .........................................42
7.7.6 Boundary Conditions for Conceptual Groundwater Flow Model ....................42
7.7.7 Groundwater Impacts to Surface Water .......................................................43
8.0 Risk Assessment.................................................................................................................45
8.1 Human Health Risk Assessment ..............................................................................45
8.1.1 Site-Specific Risk-Based Remediation Standards ........................................46
8.2 Ecological Risk Assessment ....................................................................................47
9.0 CSA Report .........................................................................................................................50
10.0 Proposed Schedule ...........................................................................................................52
11.0 References ........................................................................................................................53
Appendix A – Notice of Regulatory Requirements Letter from John E. Skvarla, III, Secretary,
State of North Carolina, to Paul Newton, Duke Energy, dated August 13, 2014.
Appendix B – Review of Groundwater Assessment Work Plan Letter from S. Jay Zimmerman,
Chief, Water Quality Regional Operations Section, NCDENR, To Harry Sideris,
Duke Energy, dated November 4, 2014.
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
Table of Contents
Figures
1. Site Location Map
2. Site Layout Map
3. Proposed Well and Sample Location Map
Tables
1. Groundwater Monitoring Requirements
2. Monitoring Well Locations
3. Exceedances of 2L Standards
4. Environmental Exploration and Sampling Plan
5. Soil and Ash Parameters and Analytical Methods
6. Groundwater, Surface Water, and Seep Parameters and Constituent Analytical Methods
7. Historical Groundwater Analytical Results (Compliance and Voluntary Monitoring Wells)
8. Historical Surface Water Analytical Results (Ash Basin)
9. Historical Ash Analytical Results (Structural Fill and Ash Landfill)
10. Historical Ash Leachate Analytical Results (Ash Basin)
11. Historical Landfill Leachate Analytical Results (RAB Ash Landfill)
12. August 2014 Seep Sample Analytical Results
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
Executive Summary
Executive Summary
Duke Energy Carolinas, LLC (Duke Energy) owns and operates the Allen Steam Station (Allen)
located along the Catawba River in Gaston County near the town of Belmont, North Carolina
(see Figure 1). Allen began operation in 1957 as a coal-fired generating station and currently
operates five coal-fired units. The coal ash residue from Allen’s coal combustion process has
historically been disposed in the station’s ash basin located to the south of the station and
adjacent to the Catawba River. The discharge from the ash basin is permitted by the North
Carolina Department of Environment and Natural Resources (NCDENR) Division of Water
Resources (DWR) under the National Pollutant Discharge Elimination System (NPDES) Permit
NC0004979.
Duke Energy has performed voluntary groundwater monitoring around the ash basin from May
2004 until November 2010. The voluntary groundwater monitoring wells were sampled two
times each year and the analytical results were submitted to DWR. Groundwater monitoring as
required by the NPDES permit began in March 2011. The system of compliance groundwater
monitoring wells required for the NPDES permit is sampled three times a year and the analytical
results are submitted to the DWR. The compliance groundwater monitoring is performed in
addition to the normal NPDES monitoring of the discharge flows from the ash basin.
It is Duke Energy’s intention that the assessment will collect additional data to validate and
expand the knowledge of the groundwater system at the ash basin. The proposed assessment
plan will provide the basis for a data-driven approach to additional actions related to
groundwater conditions if required by the results of the assessment and for closure.
On August 13, 2014, NCDENR issued a Notice of Regulatory Requirements (NORR) letter to
Duke Energy pursuant to Title 15A North Carolina Administrative Code Chapter (15A NCAC)
02L.0106. The NORR stipulates that for each coal-fueled plant owned, Duke Energy will
conduct a comprehensive site assessment (CSA) that includes a Groundwater Assessment
Work Plan (Work Plan) and a receptor survey. In accordance with the requirements of the
NORR, HDR completed a receptor survey to identify all receptors within a 0.5-mile radius (2,640
feet) of the Allen ash basin compliance boundary. This receptor survey also addressed the
requirements of the General Assembly of North Carolina Session 2013 Senate Bill 729 Ratified
Bill (SB 729). Similar requirements to perform a groundwater assessment are found in SB 729,
which revised North Carolina General Statute 130A-309.209(a).
In accordance with the NORR, Duke Energy submitted a Groundwater Assessment Work Plan
(GAWP) to the NCDENR on September 25, 2014. Subsequent to their review, the NCDENR
provided comments to the GAWP in a letter dated November 4, 2014. The letter included
general comments that pertained to each of the work plans prepared for Duke Energy’s 14 coal
ash sites in North Carolina, as well as comments specific to the Allen work plan and site. This
Revised GWAP has been prepared to address the general and site-specific comments made by
NCDENR in the November 4, 2014 letter.
ES-1
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
Executive Summary
Soil and groundwater sampling will be performed to provide information pertaining to the
horizontal and vertical extent of potential soil and groundwater contamination. This will be
performed by sampling select existing wells, installing and sampling approximately 32 nested
monitoring well pairs (shallow and deep), 4 additional shallow monitoring wells, and 5 bedrock
monitoring wells, and collecting soil and ash samples. This work will provide additional
information on the chemical and physical characteristics of site soils and ash, as well as the
geological and hydrogeological features of the site that influence groundwater flow and direction
and potential transport of constituents from the active ash basin and inactive ash basin.
Samples of ash basin surface water will be collected and used to evaluate potential impacts to
groundwater and surface water. In addition, seep samples will be collected from locations
identified in August 2014 (as part of Duke Energy’s NPDES permit renewal application) to
evaluate potential impacts to surface water.
The information obtained through implementation of this Work Plan will be utilized to prepare a
CSA report in accordance with the requirements of the NORR. If it is determined that additional
investigations are required during the review of existing data or data developed from this
assessment, Duke Energy and HDR will notify the NCDENR regional office prior to initiating
additional sampling or investigations.
HDR will also perform an assessment of risks to human health and safety and to the
environment. This assessment will include the preparation of a conceptual site model illustrating
potential pathways from the source to possible receptors.
ES-2
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
1.0 Introduction
1.0 Introduction
Duke Energy Carolinas, LLC (Duke Energy) owns and operates the Allen Steam Station (Allen)
located along the Catawba River in Gaston County near the town of Belmont, North Carolina
(see Figure 1). Allen began operation in 1957 as a coal-fired generating station and currently
operates five coal-fired units. The coal ash residue from Allen’s coal combustion process has
historically been disposed in the station’s ash basin located to the south of the station and
adjacent to the Catawba River. The discharge from the ash basin is permitted by the North
Carolina Department of Environment and Natural Resources (NCDENR) Division of Water
Resources (DWR) under the National Pollutant Discharge Elimination System (NPDES) Permit
NC0004979.
Duke Energy has performed voluntary groundwater monitoring around the ash basin from May
2004 until November 2010. The voluntary groundwater monitoring wells were sampled two
times each year and the analytical results were submitted to DWR. Groundwater monitoring as
required by the NPDES permit began in March 2011. The system of compliance groundwater
monitoring wells required for the NPDES permit is sampled three times a year and the analytical
results are submitted to the DWR. The compliance groundwater monitoring is performed in
addition to the normal NPDES monitoring of the discharge flows from the ash basin.
It is Duke Energy’s intention that the assessment will collect additional data to validate and
expand the knowledge of the groundwater system at the ash basin. The proposed assessment
plan will provide the basis for a data-driven approach to additional actions related to
groundwater conditions if required by the results of the assessment and for closure.
On August 13, 2014, NCDENR issued a Notice of Regulatory Requirements (NORR) letter to
Duke Energy pursuant to Title 15A North Carolina Administrative Code (15A NCAC) Chapter
02L.0106. The NORR stipulates that for each coal-fueled plant owned, Duke Energy will
conduct a comprehensive site assessment (CSA) that includes a Groundwater Assessment
Work Plan (Work Plan) and a receptor survey. In accordance with the requirements of the
NORR, HDR has completed a receptor survey to identify all receptors within a 0.5-mile radius
(2,640 feet) of the Allen ash basin compliance boundary. The NORR letter is included as
Appendix A.
The Coal Ash Management Act 2014 – General Assembly of North Carolina Senate Bill 729
Ratified Bill (Session 2013) (SB 729) revised North Carolina General Statute 130A-309.209(a)
to require the following:
(a) Groundwater Assessment of Coal Combustion Residuals Surface Impoundments. –
The owner of a coal combustion residuals surface impoundment shall conduct
groundwater monitoring and assessment as provided in this subsection. The
requirements for groundwater monitoring and assessment set out in this subsection
are in addition to any other groundwater monitoring and assessment requirements
applicable to the owners of coal combustion residuals surface impoundments.
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
1.0 Introduction
(1) No later than December 31, 2014, the owner of a coal combustion residuals
surface impoundment shall submit a proposed Groundwater Assessment Plan for
the impoundment to the Department for its review and approval. The
Groundwater Assessment Plan shall, at a minimum, provide for all of the
following:
a. A description of all receptors and significant exposure pathways.
b. An assessment of the horizontal and vertical e xtent of soil and groundwater
contamination for all contaminants confirmed to be present in groundwater in
exceedance of groundwater quality standards.
c. A description of all significant f actors affecting movement and transport of
contaminants.
d. A description of the geological and hydrogeological features influencing the
chemical and physical character of the contaminants.
e. A schedule for continued groundwater monitoring.
f. Any other information related to groundwater assessment required by the
Department.
(2) The Department shall approve the Groundwater Assessment Plan if it determines
that the Plan complies with the requirements of this subsection and will be
sufficient to protect public health, safety, and welfare; the environment; and natural
resources.
(3) No later than 10 days from approval of the Groundwater Assessment Plan, the
owner shall begin implementation of the Plan.
(4) No later than 180 days from approval of the Groundwater Assessment Plan, the
owner shall submit a Groundwater Assessment Report to the Department. The
Report shall describe all exceedances o f groundwater quality standards associated
with the impoundment.
This work plan addresses the requirements of 130A-309.209(a)(1) (a) through (f) and the
requirements of the NORR.
On behalf of Duke Energy, HDR submitted to NCDENR a proposed Work Plan for the Allen site
dated September 25, 2014. Subsequently, NCDENR issued a comment letter dated November
4, 2014, containing both general comments applicable to all 14 of Duke Energy ash basin
facilities and site-specific comments for the Allen site. In response to these comments, HDR has
prepared this revised Work Plan for performing the groundwater assessment as prescribed in
the NORR. If it is determined that additional investigations are required during the review of
existing data or data developed from this assessment, Duke Energy and HDR will notify the
NCDENR regional office prior to initiating additional sampling or investigations.
HDR will also perform an assessment of risks to human health and safety and to the
environment. This assessment will include the preparation of a conceptual site model illustrating
potential pathways from the source to possible receptors.
The purpose of the work plan contains a description of the activities proposed to meet the
requirements of 15A NCAC 02L .0106(g). This rule requires:
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
1.0 Introduction
(g) The site assessment conducted pursuant to the requirements of Paragraph (c) of this
Rule, shall include:
(1) The source and cause of contamination;
(2) Any imminent hazards to public health and safety and actions taken to mitigate them
in accordance with Paragraph (f) of this Rule;
(3) All receptors and significant exposure pathways;
(4) The horizontal and vertical extent of soil and groundwater contamination and all
significant factors affecting contaminant transport; and
(5) Geological and hydrogeological features influencing the movement, chemical, and
physical character of the contaminants.
The work proposed in this plan will provide the information sufficient to satisfy the requirements
of the rule. However, uncertainties may still exist due to the following factors:
• The natural variations and the complex nature of the geological and hydrogeological
characteristics involved with understanding the movement, chemical, and physical
character of the contaminants
• The size of the site
• The time frame mandated by the Coal Ash Management Act (CAMA). Site assessments
are most effectively performed in a multi-phase approach where data obtained in a
particular phase of the investigation can be reviewed and used to refine the subsequent
phases of investigation. The mandated 180-day time frame will prevent this approach
from being utilized.
The 180-day time frame will limit the number of sampling events that can be performed after
well installation and prior to report production. Effectively, this time frame will likely reduce the
number of sampling events within the proposed wells to a single sampling event for the CSA
report.
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
2.0 Site History
2.0 Site History
2.1 Plant Description
Allen is a five-unit, coal-fired, electric generating plant with a capacity of 1,140 megawatts
located on the west bank of the Catawba River on Lake Wylie in Belmont, Gaston County, North
Carolina. The site is located east of South Point Road (NC 273) and the surrounding area
generally consists of residential properties, undeveloped land, and Lake Wylie (Figure 1).
The station’s ash basin is situated between the Allen station to the north and topographic
divides to the west (along South Point Road) and south (along Reese Wilson Road), which both
drop in elevation to the east toward Lake Wylie (Figure 2). The topographic divide along South
Point Road likely functions as a groundwater divide. The topography at the site generally slopes
downward from that divide toward Lake Wylie. The entire Allen site is approximately 1,009 acres
in area.
Duke Energy operates the Catawba-Wateree Project (Federal Energy Regulatory Commission
[FERC] Project No. 2232). Lake Wylie reservoir is part of the Catawba-Wateree project and is
used for hydroelectric generation, municipal water supply, and recreation. Duke Energy has
performed a review of property ownership of the FERC project boundary property within the ash
basin compliance boundary (described in Section 2.3). The review indicated that Duke Energy
does own all of the property within the project boundary except for one parcel located east of
the ash basin within the FERC boundary (Lake Wylie) and the ash basin compliance boundary.
However, Duke Energy does have water rights for the parcel. The Duke Energy property
boundary and the ash basin compliance boundary are shown on Figures 2 and 3.
2.2 Ash Basin Description
The ash basin system at the site has historically been used to retain and settle ash generated
from coal combustion at the Allen plant. The ash basin system consists of an active ash basin
and an inactive ash basin. In general, the ash basin is located in historical depressions formed
from tributaries that flowed toward Lake Wylie (Catawba River) as shown on Figure 2. There are
two earthen dikes impounding the active ash basin: the East Dike, located along the west bank
of Lake Wylie, and the North Dike, separating the active and inactive ash basins. The original
ash basin at the Allen site (the inactive ash basin) began operation in 1957 and was formed by
constructing the earthen North Dike and the north portion of the East Dike where tributaries
flowed toward Lake Wylie. As the original ash basin capacity diminished over time, the active
ash basin was formed in 1973 by constructing the southern portion of the East Dike. Ash has
been sluiced to the active ash basin since 1973.
The surface area of the active ash basin is approximately 169 acres with an operating pond
elevation of approximately 634.5 feet. The normal water elevation of Lake Wylie is
approximately 568.7 feet. The area contained within the entire ash basin waste boundary, which
is shown on Figures 2 and 3, is approximately 322 acres in area.
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
2.0 Site History
Two unlined dry ash storage areas, two unlined structural fill units, and a lined dry ash landfill
are located on top of the inactive ash basin. The ash landfill was constructed in 2009.
Construction of the structural fill units began in 2003 and was completed in 2009. The dry ash
storage areas were constructed in 1996. Additional information pertaining to each ash
management unit is provided in Section 5.1.
The ash basin is operated as an integral part of the station’s wastewater treatment system,
which receives flows from the ash removal system, coal pile runoff, landfill leachate, flue gas
desulfurization (FGD) wastewater, the station yard drain sump, and stormwater flows. Due to
variability in station operations and weather, the inflows to the ash basin are highly variable.
Effluent from the ash basin is discharged from the discharge tower to Lake Wylie via a 42-inch-
diameter reinforced concrete pipe located in the southeastern portion of the ash basin. The
water surface elevation in the ash basin is controlled by the use of stoplogs in the discharge
tower.
2.3 Regulatory Requirements
The NPDES program regulates wastewater discharges to surface waters to ensure that surface
water quality standards are maintained. Allen operates under NPDES Permit NC0004979 which
authorizes Duke Energy to discharge once-through cooling water (Outfall 001); operate a septic
tank and ash pond with pH adjustment and domestic wastewater discharge, stormwater runoff,
ash sluice, water treatment system wastewaters, FGD system blowdown, landfill leachate, and
miscellaneous cleaning and maintenance wash waters (Outfall 002); coal yard sump overflow
(Outfall 002A); power house sump overflow (Outfall 002B); miscellaneous equipment for non-
contact cooling and sealing water (Outfall 003); and miscellaneous non-contact cooling water,
vehicle washwater, and intake screen backwash (Outfall 004) to the Catawba River in
accordance with effluent limitations, monitoring requirements, and other conditions set forth in
the permit. Furthermore, the NPDES Permit authorizes Duke Energy to continue operation of
the FGD wet scrubber wastewater treatment system discharging to the ash settling basin
through internal Outfall 005.
The NPDES permitting program requires that permits be renewed every 5 years. The most
recent NPDES permit renewal at Allen became effective on March 1, 2011, and expires May 31,
2015.
In addition to surface water monitoring, the NPDES permit requires groundwater monitoring.
Groundwater monitoring has been performed in accordance with the permit conditions
beginning in March 2011. NPDES Permit Condition A (11), Version 1.1, dated June 15, 2011,
lists the groundwater monitoring wells to be sampled, the parameters and constituents to be
measured and analyzed, and the requirements for sampling frequency and reporting results.
These requirements are provided in Table 1.
The compliance boundary for groundwater quality at the Allen ash basin site is defined in
accordance with Title 15A NCAC 02L .0107(a) as being established at either 500 feet from the
waste boundary or at the property boundary, whichever is closer to the waste. The location of
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
2.0 Site History
the ash basin compliance monitoring wells, the ash basin waste boundary, and the compliance
boundary are shown on Figure 2.
The locations for the compliance groundwater monitoring wells were approved by the NCDENR
DWR Aquifer Protection Section (APS). All compliance monitoring wells included in Table 2 are
sampled three times per year (in March, July, and November). Analytical results are submitted
to the DWR before the last day of the month following the date of sampling for all compliance
monitoring wells except AB-9S, AB-9D, AB-10S, and AB-10D.
The compliance groundwater monitoring system for the Allen ash basin consists of the following
monitoring wells: AB-1R, AB-4S, AB-4D, AB-9S, AB-9D, AB-10S, AB-10D, AB-11D, AB-12S,
AB-12D, AB-13S, AB-13D, and AB-14D (shown on Figures 2 and 3). All the compliance
monitoring wells were installed in 2010.
One or more groundwater quality standards (2L Standards) have been exceeded in
groundwater samples collected at monitoring wells AB-1R, AB-4S, AB-4D, AB-9S, AB-9D,
AB-10S, AB-10D, AB-11D, AB-12S, AB-12D, AB-13S, AB-13D, and AB-14D. Exceedances
have occurred for boron, iron, manganese, pH, and nickel. Table 3 presents exceedances
measured from March 2011 through July 2014.
Monitoring wells AB-4S, AB-9S, AB-10S, AB-12S, and AB-13S were installed with 15-foot well
screens placed above auger refusal to monitor the shallow aquifer within the saprolite layer.
Monitoring wells AB-4D, AB-9D, AB-10D, AB-11D, AB-12D, AB-13D, and AB-14D were installed
with either 5-foot or 10-foot well screens placed in the uppermost region of the fractured rock
transition zone.
Monitoring well AB-1R is located to the northwest of the inactive ash basin and is considered by
Duke Energy to represent background water quality at the site. AB-1R was installed with a
20-foot well screen placed above auger refusal to monitor the shallow aquifer within the
saprolite layer.
With the exception of monitoring wells AB-9S, AB-9D, AB-10S, and AB-10D, the ash basin
monitoring wells were installed at or near the compliance boundary. AB-11D is located to the
south of the active ash basin. Monitoring wells AB-12S, AB-12D, AB-4S, AB-4D, AB-13S, and
AB-13D are generally located to the west of the active ash basin. Monitoring well AB-14D is
located to the south of a portion of the inactive ash basin and near the western extent of the
property.
Monitoring wells AB-9S, AB-9D, AB-10S, and AB-10D are located inside of the compliance
boundary downgradient from the inactive and active ash basins (where it was not possible to
access the compliance boundary). Monitoring wells AB-9S and AB-9D are located to the
southeast of the inactive ash basin and AB-10S and AB-10D are located to the east of the
active ash basin. Compliance with 2L Standards (at the compliance boundary) for AB-9S,
AB-9D, AB-10S, and AB-10D is determined by using predictive calculations or a groundwater
model. For these four monitoring wells, Duke Energy uses a groundwater model to predict the
concentrations at the compliance boundary. The predicted results from the groundwater model
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
2.0 Site History
and the analytical results for samples collected during the sampling events are to be submitted
to the DWR annually.
Note that monitoring wells AB-1, AB-2, AB-2D, AB-5, AB-6A, AB-6R, and AB-8 were installed by
Duke Energy in 2004 and 2005 as part of a voluntary monitoring system.1 Voluntary monitoring
well AB-8 was found damaged and abandoned in 2010. No samples are currently being
collected from the voluntary wells. The existing voluntary wells are shown on Figures 2 and 3.
1 AB-1 and AB-8 were abandoned in 2010.
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
3.0 Receptor Information
3.0 Receptor Information
The August 13, 2014, NORR states:
No later than October 14th, 2014 as authorized pursuant to 15A NCAC 02L
.0106(g), the DWR is requesting that Duke perform a receptor survey at each of
the subject facilities and submitted to the DWR. The receptor survey is required
by 15A NCAC 02L .0106(g) and shall include identification of all receptors within
a radius of 2,640 feet (one-half mile) from the established compliance boundary
identified in the respective National Pollutant Discharge Elimination System
(NPDES) permits. Receptors shall include, but shall not be limited to, public and
private water supply wells (including irrigation wells and unused or abandoned
wells) and surface water features within one-half mile of the facility compliance
boundary. For those facilities for which Duke has already submitted a receptor
survey, please update your submittals to ensure they meet the requirements
stated in this letter and referenced attachments and submit them with the others.
If they do not meet these requirements, you must modify and resubmit the plans.
The results of the receptor survey shall be presented on a sufficiently scaled
map. The map shall show the coal ash facility location, the facility property
boundary, the waste and compliance boundaries, and all monitoring wells listed
in the respective NPDES permits. Any identified water supply wells shall be
located on the map and shall have the well owner's name and location address
listed on a separate table that can be matched to its location on the map.
In accordance with the requirements of the NORR, HDR completed and submitted the receptor
survey to NCDENR (HDR 2014A) in September 2014. HDR subsequently submitted to
NCDENR a supplement to the receptor survey (HDR 2014B) in November 2014. The
supplementary information was obtained from responses to water supply well survey
questionnaires mailed to property owners within a 0.5-mile radius of the Allen ash basin
compliance boundary requesting information on the presence of water supply wells and well
usage.
The receptor survey includes a map showing the coal ash facility location, the facility property
boundary, the waste and compliance boundaries, and all monitoring wells listed in the NPDES
permit. The identified water supply wells are located on the map and the well owner's name and
location address are listed on a separate table that can be matched to its location on the map.
During completion of the CSA, HDR will update the receptor information as necessary in
general accordance with the CSA receptor survey requirements.
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Allen Steam Station Ash Basin
4.0 Regional Geology and Hydrogeology
4.0 Regional Geology and Hydrogeology
North Carolina is divided into distinct regions by portions of three physiographic provinces: the
Atlantic Coastal Plain, Piedmont, and Blue Ridge (Fenneman 1938). The Allen site is located in
the Charlotte terrane within the Piedmont province. The Piedmont province is bounded to the
east and southeast by the Atlantic Coastal Plain and to the west by the escarpment of the Blue
Ridge Mountains, covering a distance of 150 to 225 miles (LeGrand 2004).
The topography of the Piedmont region is characterized by low, rounded hills and long, rolling,
northeast-southwest trending ridges (Heath 1984). Stream valley to ridge relief in most areas
ranges from 75 to 200 feet. Along the Coastal Plain boundary, the Piedmont region rises from
an elevation of 300 feet above mean sea level to the base of the Blue Ridge Mountains at an
elevation of 1,500 feet (LeGrand 2004).
The Charlotte terrane consists primarily of igneous and metamorphic bedrock. The fractured
bedrock is overlain by a mantle of unconsolidated material known as regolith. The regolith
includes residual soil and saprolite zones and, where present, alluvium. Saprolite, the product of
chemical weathering of the underlying bedrock, is typically composed of clay and coarser
granular material and reflects the texture and structure of the rock from which it was formed.
The weathering products of granitic rocks are quartz-rich and sandy textured. Rocks poor in
quartz and rich in feldspar and ferro-magnesium minerals form a more clayey saprolite.
The groundwater system in the Piedmont Province in most cases is comprised of two
interconnected layers, or mediums: 1) residual soil/saprolite and weathered fractured rock
(regolith) overlying, and 2) fractured crystalline bedrock (Heath 1980; Harned and Daniel 1992).
The regolith layer is a thoroughly weathered and structureless residual soil that occurs near the
ground surface with the degree of weathering decreasing with depth. The residual soil grades
into saprolite, a coarser-grained material that retains the structure of the parent bedrock.
Beneath the saprolite, partially weathered/fractured bedrock occurs with depth until sound
bedrock is encountered. This mantle of residual soil, saprolite, and weathered/fractured rock is a
hydrogeologic unit that covers and crosses various types of rock (LeGrand 1988). This layer
serves as the principal storage reservoir and provides an intergranular medium through which
the recharge and discharge of water from the underlying fractured rock occurs. Within the
fractured crystalline bedrock layer, the fractures control both the hydraulic conductivity and
storage capacity of the rock mass. A transition zone at the base of the regolith has been
interpreted to be present in many areas of the Piedmont. The zone consists of partially
weathered/fractured bedrock and lesser amounts of saprolite that grades into bedrock and has
been described as “being the most permeable part of the system, even slightly more permeable
than the soil zone” (Harned and Daniel 1992). The zone thins and thickens within short
distances and its boundaries may be difficult to distinguish. It has been suggested that the zone
may serve as a conduit of rapid flow and transmission of contaminated water (Harned and
Daniel 1992)
The igneous and metamorphic bedrock in the Piedmont consist of interlocking crystals and
primary porosity is very low, generally less than 3 percent. Secondary porosity of crystalline
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4.0 Regional Geology and Hydrogeology
bedrock due to weathering and fractures ranges from 1 to 10 percent (Freeze and Cherry 1979)
but porosity values of from 1 to 3 percent are more typical (Daniel and Sharpless 1983). Daniel
(1990) reported that the porosity of the regolith ranges from 35 to 55 percent near land surface
but decreases with depth as the degree of weathering decreases.
LeGrand’s (1988, 1989) conceptual model of the groundwater setting in the Piedmont
incorporates the above two-medium system into an entity that is useful for the description of
groundwater conditions. That entity is the surface drainage basin that contains a perennial
stream (LeGrand 1988). Each basin is similar to adjacent basins and the conditions are
generally repetitive from basin to basin. Within a basin, movement of groundwater is generally
restricted to the area extending from the drainage divides to a perennial stream (Slope-Aquifer
System; LeGrand 1988, 1989). Rarely does groundwater move beneath a perennial stream to
another more distant stream or across drainage divides (LeGrand 1989). The crests of the water
table undulations represent natural groundwater divides within a slope-aquifer system and may
limit the area of influence of wells or contaminant plumes located within their boundaries. The
concave topographic areas between the topographic divides may be considered as flow
compartments that are open-ended down slope.
Therefore, in most cases in the Piedmont, the groundwater system is a two-medium system
(LeGrand 1988) restricted to the local drainage basin. The groundwater occurs in a system
composed of two interconnected layers: residual soil/saprolite and weathered rock overlying
fractured crystalline rock separated by the transition zone. Typically, the residual soil/saprolite is
partially saturated and the water table fluctuates within it. Water movement is generally through
the weathered/fractured and fractured bedrock. The near-surface fractured crystalline rocks can
form extensive aquifers. The character of such aquifers results from the combined effects of the
rock type, fracture system, topography, and weathering. Topography exerts an influence on
both weathering and the opening of fractures, while the weathering of the crystalline rock
modifies both transmissive and storage characteristics.
Groundwater flow paths in the Piedmont are almost invariably restricted to the zone underlying
the topographic slope extending from a topographic divide to an adjacent stream. Under natural
conditions, the general direction of groundwater flow can be approximated from the surface
topography (LeGrand 2004).
Groundwater recharge in the Piedmont is derived entirely from infiltration of local precipitation.
Groundwater recharge occurs in areas of higher topography (i.e., hilltops) and groundwater
discharge occurs in lowland areas bordering surface water bodies, marshes, and floodplains
(LeGrand 2004). Average annual precipitation in the Piedmont ranges from 42 inches to 46
inches. Mean annual recharge in the Piedmont ranges from 4.0 inches to 9.7 inches per year
(Daniel 2001).
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5.0 Initial Conceptual Site Model
5.0 Initial Conceptual Site Model
The following Initial Conceptual Site Model (ICSM) has been developed for the Allen site using
available regional data and site-specific data (e.g., boring logs, well construction records, etc.).
Although the groundwater flow system at the site is not fully understood and heterogeneities
exist, the available data indicates that the LeGrand Slope-Aquifer hydrogeologic conceptual
model for sites within the Piedmont, as described in Section 4.0, is a reasonable preliminary
representation of site conditions. The ICSM served as the foundation for the development of
proposed field activities and data collection presented in Section 7.0. The ICSM will be
redefined as needed as additional site-specific information is obtained during the site
assessment process.
The ICSM serves as the basis for understanding the hydrogeologic characteristics of the site as
well as the characteristics of the ash sources and will serve as the basis for the Site Conceptual
Model (SCM) discussed in Section 7.5.
In general, the ICSM identified the need for the following additional information concerning the
site and ash:
• Delineation of the extent of possible soil and groundwater contamination
• Additional information concerning the direction and velocity of groundwater flow
• Information on the constituents and concentrations found in the site ash
• Properties of site materials influencing fate and transport of constituents found in ash
• Information on possible impacts to seeps and surface water from the constituents found
in the ash
The assessment work plan found in Section 7.0 was developed in order to collect and to
perform the analyses to provide this information.
5.1 Physical Site Characteristics
The original ash basin at the Allen site (the inactive ash basin) began operation in 1957 and was
formed by constructing the earthen North Dike and the north portion of the East Dike where
tributaries flowed toward Lake Wylie. Coal ash was sluiced to the inactive basin until the active
ash basin was constructed in 1973. The active ash basin was formed by constructing the
southern portion of the East Dike. In general, the ash basin is located in historical depressions
formed from tributaries that flowed toward Lake Wylie (Catawba River).
Topography at the Allen site ranges from approximately 650 feet to 680 feet elevation near the
west and southwest boundaries of the site to an approximate low elevation of 570 feet at the
shoreline of Lake Wylie. Topography generally slopes from a west to east direction with an
elevation loss of approximately 110 feet to 80 feet over an approximate distance of 0.8 miles.
Topographic divides are located to the west (along South Point Road) and south (along Reese
Wilson Road) of the ash basin, which both drop in elevation to the east toward Lake Wylie.
Surface water drainage generally follows site topography and flows from the southwest and
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5.0 Initial Conceptual Site Model
west to the east across the site except where natural drainage patterns have been modified by
the ash basin or other construction. The full operating pond elevation for the active ash basin is
approximately 634.5 feet. The normal water elevation of Lake Wylie is approximately 568.7 feet.
In addition to the ash basin, two unlined dry ash storage areas, two unlined structural fill units,
and a lined dry ash landfill are located on top of the inactive ash basin. The ash landfill was
constructed in 2009. Construction of the structural fill units began in 2003 and was completed in
2009. The dry ash storage areas were constructed in 1996. Additional information pertaining to
each ash management unit is provided below. Locations of site features are shown on Figures
2 and 3.
5.1.1 Ash Basin
Coal ash residue from the coal combustion process has historically been disposed in the Allen
ash basin. The area contained within the entire ash basin waste boundary, which is shown on
Figures 2 and 3, is approximately 322 acres in area. The ash basin system is comprised of an
inactive ash basin and an active ash basin. The active ash basin is approximately 169 acres in
area and contains an estimated 7,660,000 tons of CCR material. The inactive ash basin is
approximately 132 acres in area and contains approximately 3,920,000 tons of CCR material.
The inactive ash basin was commissioned in 1957 and is located adjacent to and north of the
active ash basin. Coal ash was sluiced to the inactive ash basin until the active ash basin was
constructed in 1973. Fly ash precipitated from flue gas and bottom ash collected in the bottom
of the boilers were sluiced to the ash basin using conveyance water withdrawn from Lake Wylie
(Catawba River). Since 2009, fly ash has been dry-handled and disposed in the on-site ash
landfill (described below), and bottom ash has continued to be sluiced to the active ash basin.
During operations, the sluice lines discharge the water/ash slurry (and other flows) into the
northern portion of the active ash basin. Primary Ponds 1, 2, and 3 which were constructed in
approximately 2004 are located in the northern portion of the active ash basin. Currently,
Primary Ponds 2 and 3 are utilized for settling purposes.
The other inflows to the ash basin include flows from coal pile runoff, landfill leachate, FGD
wastewater, the station yard drain sump, and stormwater flows. Due to variability in station
operations and weather, the inflows to the ash basin are highly variable.
Effluent from the ash basin is discharged from the discharge tower to Lake Wylie via a 42-inch-
diameter reinforced concrete pipe located in the southeastern portion of the ash basin. The
water surface elevation in the ash basin is controlled by the use of stoplogs in the discharge
tower.
5.1.2 Ash Landfill
The ash landfill unit, referred to as the Retired Ash Basin (RAB) Ash Landfill (NCDENR Division
of Waste Management (DWM) Solid Waste Section Permit No. 3612-INDUS), is located on the
eastern portion of the Allen Steam Station property, approximately 0.25 miles south of the Allen
Steam Station in the footprint of the RAB. The landfill is bound to the north, east, south, and
west by earthen dikes. The Catawba River is located to the east. To the south of and adjacent
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5.0 Initial Conceptual Site Model
to the RAB is the existing active ash basin, and to the west is a structural fill area. The landfill is
permitted to receive coal combustion residuals (CCR) including fly ash, bottom ash, boiler slag,
mill rejects, and flue gas desulfurization (FGD) residue generated by Duke Energy Carolinas,
LLC, including at the Allen Steam Station.
Once completed, the RAB Ash Landfill is planned to contain two phases (Phase I and Phase II)
covering a total of 47 acres. Phase I has been constructed and encompasses 25 acres on the
southern half of the landfill footprint. The estimated gross capacity of Phase I is 2,082,500 cubic
yards. Phase II has not yet been constructed and is planned to encompass 22 acres
immediately north of the Phase I footprint. The estimated gross capacity of Phase II is
3,958,200 cubic yards. The entire landfill facility, including the waste footprint, associated
perimeter berms, ditches, stormwater management systems and roads, is projected to
encompass an area of approximately 62 acres, when complete. The approximate boundary of
the RAB Ash Landfill is shown on Figures 2 and 3.
The Permit to Construct Phase I of the landfill was issued by NCDENR DWM in September
2008. Its initial Permit to Operate was issued by NCDENR DWM in December 2009, and the
most recent Permit to Operate renewal was issued in December 2014. The landfill was
constructed with a leachate collection and removal system and a three-component liner system
consisting of a primary geomembrane, secondary geomembrane (with a leak detection system
between them), and clay soil liner. Placement of waste material in the RAB Ash Landfill began
in December 2009. Phase I contact stormwater and leachate are collected in the leachate
collection pipe system and then pumped to the discharge location in the northeastern portion of
the active ash basin.
5.1.3 Structural Fills
Two unlined Distribution of Residuals Solids (DORS) structural fills are located on top of the
western portion of the inactive ash basin, adjacent to and west of the RAB Ash Landfill. These
fills were constructed of ponded ash removed from the active ash basin per Duke Energy’s
DORS Permit issued by the Division of Water Quality. Placement of dry ponded ash in the
structural fills began in 2003 and was completed in 2009. During and following the completion of
filling, the structural fill areas were graded to drain, and soil cover was placed on the top slopes
and side slopes, and vegetation was established. The eastern of the two fills covers
approximately 17 acres and contains approximately 500,000 tons of CCR material. The
western of the two fills covers approximately 17 acres and contains approximately 328,000 tons
of CCR material.
5.1.4 Ash Storage
Two unlined ash storage areas are located on top of the western portion of the inactive ash
basin, adjacent to and west of the two DORS structural fills. Similar to the two DORS structural
fills, the ash storage areas were constructed in 1996 by excavating ash from the northern
portion of the active ash basin in order to provide capacity for sluiced ash in the active ash basin
and the future construction of Primary Ponds 1, 2, and 3. Following the completion of
stockpiling, the ash storage areas were graded to drain, and a minimum of 18 and 24 inches of
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5.0 Initial Conceptual Site Model
soil cover were placed on the top slopes and side slopes, respectively, and vegetation was
established. Approximately 300,000 cubic yards of ash is stored in the ash storage areas, which
encompass an area of approximately 15-20 acres of the western portion of the inactive ash
basin.
5.2 Source Characteristics
The ash in the ash basin consists of fly ash and bottom ash produced form the combustion of
coal. The physical and chemical properties of coal ash are determined by reactions that occur
during the combustion of the coal and subsequent cooling of the flue gas. In general, coal is
dried, pulverized, and conveyed to the burner area of a boiler for combustion. Material that
forms larger particles of ash and falls to the bottom of the boiler is referred to as bottom ash.
Smaller particles of ash, fly ash, are carried upward in the flue gas and are captured by an air
pollution control device. Approximately 70 percent to 80 percent of the ash produced during
coal combustion is fly ash (EPRI 1993). Typically, 65 percent to 90 percent of fly ash has
particle sizes that are less than 0.010 millimeter (mm). Bottom ash particle diameters can vary
from approximately 38 mm to 0.05 mm.
The chemical composition of coal ash is determined based on many factors including the source
of the coal, the type of boiler where the combustion occurs (the thermodynamics of the boiler),
and air pollution control technologies employed. The major elemental composition of fly ash
(approximately 90 percent by weight) is composed of mineral oxides of silicon, aluminum, iron,
and calcium. Minor constituents such as magnesium, potassium, titanium, and sulfur comprise
approximately 8 percent of the mineral component, while trace constituents such as arsenic,
cadmium, lead, mercury, and selenium make up less than approximately 1 percent of the total
composition (EPRI 2009). Other trace constituents in coal ash (fly ash and bottom ash) consist
of antimony, barium, beryllium, boron, chromium, copper, lead, mercury, molybdenum, nickel,
selenium, strontium, thallium, uranium, vanadium, and zinc (EPRI 2009).
In addition to these constituents, coal ash leachate contains chloride, fluoride, sulfate, and
sulfide. In the U.S. Environmental Protection Agency’s (EPA’s) Proposed Rules Disposal of
Coal Combustion Residuals From Electric Utilities Federal Register / Vol. 75, No. 118 / Monday,
June 21, 2010, 35206, EPA proposed that the following constituents be used as indicators of
groundwater contamination in the detection monitoring program for coal combustion residual
landfills and surface impoundments: boron, chloride, conductivity, fluoride, pH, sulfate, sulfide,
and total dissolved solids (TDS). In selecting the parameters for detection monitoring, EPA
selected constituents that are present in coal combustion residual that would move rapidly
through the subsurface, thereby providing an early indication that contaminants were migrating
from the landfill or ash basin.
In the 1998 Report to Congress Wastes from the Combustion of Fossil Fuels (USEPA 1998),
EPA presented waste characterization data for coal combustion product (CCP) wastes in
impoundments and in landfills. The constituents listed were: arsenic, barium, beryllium, boron,
cadmium, chromium, cobalt, copper, lead, manganese, nickel, selenium, silver, thallium,
strontium, vanadium, and zinc. In this report, the EPA reviewed radionuclide concentrations in
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5.0 Initial Conceptual Site Model
coal and ash and ultimately eliminated radionuclides from further consideration due to the low
risks associated with radionuclides.
The geochemical factors controlling the reactions associated with leaching of ash and the
movement and transport of the constituents leached from ash is complicated. The mechanisms
that affect movement and transport vary by constituent but, in general, are mineral equilibrium,
solubility, and adsorption onto inorganic soil particles. Due to the complexity associated with
understanding or identifying the specific mechanism controlling these processes, HDR believes
that the effect of these processes are best considered by determination of site-specific soil-
water distribution coefficient, Kd, values as described in Section 7.7.
The oxidation-reductions and precipitation-dissolution reactions that occur in a complex
environment such as an ash basin are poorly understood. In addition to the variability that might
be seen in the mineralogical composition of the ash based on different coal types, different age
of ash in the basin, etc., it would be anticipated that the chemical environment of the ash basin
would vary over time and over distance and depth, increasing the difficulty of making specific
predictions related to concentrations of specific constituents. Duke Energy has performed
limited leaching analysis on fly ash and bottom ash. Available data is presented in Table 10.
Due to the complex nature of the geochemical environment and process in the ash basin, HDR
believes that the most useful representation of the potential impacts to groundwater will be
obtained from the sampling and analyses of ash in the basin, in the ash landfills, and from
porewater and groundwater samples proposed in Section 7.0 of this work plan.
Understanding the factors controlling the mobility, retention, and transport of the constituents
that may leach from ash are also complicated by the complex nature of the geochemical
environment of the ash basin combined with the complex geochemical processes occurring in
the soils beneath the ash basin along the groundwater flow paths. Mobility, retention, and
transport of the constituents can vary by each individual constituent. As these processes are
complex and highly dependent on the mineral composition of the soils, it will not be possible to
determine with absolute clarity the specific mechanism that controls the mobility and retention of
the constituents; however, the effect of these processes will be represented by the
determination of the site-specific soil-water distribution coefficient, Kd, values as described in
Section 7.7. As described in that section, samples will be collected to develop Kd terms for the
various materials encountered at the site. These Kd terms are then to be used as part of the
groundwater modeling, if required to predict concentrations of constituents at the compliance
boundary.
The site residual soils were formed by in-place weathering of granite, quartzite, and gabbro. Iron
(Fe) and manganese (Mn) present in groundwater at a number of the on-site monitoring wells
are constituents of the bedrock, primarily in ferro-magnesium minerals. Manganese substitutes
for iron and magnesium in a number of minerals and is enriched in mafic and ultramafic
lithologies relative to felsic lithologies (1,000 parts per million [ppm] in basalt and 400 ppm in
granite; Krauskopf 1972). In the Piedmont, manganese oxides occur as thin coatings along
bedrock fractures (as well as iron oxides) and as thin coatings along relict discontinuities in
saprolite. Manganese ranges from 20 to 3,000 ppm in residual soils (Krauskopf 1972).
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5.0 Initial Conceptual Site Model
In a study in Orange County, North Carolina, Cunningham and Daniel (2001) reported
manganese in 94% and iron in 80% of the drinking water wells tested. Iron exceeded North
Carolina drinking water standards in 6% of the wells and for manganese in 24% of the wells
(Cunningham and Daniel 2001). In more recent study, Gillispie (2014) found that approximately
50% of wells in North Carolina have manganese concentrations exceeding the state standard of
0.05 mg/L (Gillispie 2014). The manganese detected in water wells at ten NC Division of Water
Resources groundwater research stations studied by Gillispie (2014) is naturally derived and
concentrations are spatially variable ranging from less than 0.01 to greater than 2 mg/L.
Approximately 50 percent of wells in North Carolina have manganese concentrations exceeding
the state standard of 0.05 mg/L (Gillispie 2014). The manganese detected in water wells at ten
NC Division of Water Resources groundwater research stations studied by Gillispie (2014) is
naturally derived and concentrations are spatially variable ranging from less than 0.01 to greater
than 2 mg/L.
5.3 Hydrogeologic Site Characteristics
Based on a review of soil boring and monitoring well installation logs provided by Duke Energy,
subsurface stratigraphy consists of the following material types: fill, ash, residuum, saprolite,
partially weathered rock (PWR), and bedrock. In general, residuum, saprolite, and PWR were
encountered on most areas of the site. Bedrock was encountered sporadically at a range of
depths across the site. Bedrock was encountered at approximately 10 feet below ground
surface (bgs) in areas on the southern extent of the site, approximately 29 feet bgs in areas on
the western extent of the site, and as deep as approximately 108 feet bgs in areas on the
eastern extent of the site near the Catawba River. In addition, alluvium is expected to be
present beneath the southern portion of the active ash basin where, based on historic USGS
topographic maps, two streams existed and flowed toward the Catawba River prior to
construction of the active ash basin. The general stratigraphic units, in sequence from the
ground surface down to boring termination, are defined as follows:
• Fill – Fill material generally consisted of re-worked silts and clays that were borrowed
from one area of the site and re-distributed to other areas. Fill was used in the
construction of dikes and presumably as cover for the ash storage area and as cover for
the Retired Ash Basin Ash Landfill.
• Ash – Of the logs reviewed, borings were advanced through ash in the area of the
Retired Ash Basin Ash Landfill only. Although previous exploration activities, for which
Duke Energy provided boring logs, did not evaluate the inactive portions of the retired
ash basin, the ash storage areas and the active ash basin, ash is expected to be present
in these ash management areas.
• Alluvium – Alluvium was not encountered in the boring information provided to HDR.
However, alluvium is expected to be present beneath the southern portion of the active
ash basin where two streams previously existed and flowed toward the Catawba River
prior to construction of the active ash basin. Alluvium is unconsolidated soil and
sediment that has been eroded and redeposited by streams and rivers.
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5.0 Initial Conceptual Site Model
• Residuum – Residuum is the in-place weathered soil that generally consists of white,
yellow, red, brown, gray, or olive sandy clay to silty sand. This unit was encountered in
various thicknesses across the site.
• Saprolite – Saprolite is soil developed by in-place weathering of rock similar to the
bedrock that consists of brown, tan, or green silty sand with trace mica. The primary
distinction from residuum is that saprolite typically retains some structure (e.g., mineral
banding) from the parent rock. This unit was found in areas across the site and was
described as white, yellow, red, or brown silty extremely weathered rock with relict rock
structure.
• Partially Weathered Rock (PWR) – PWR occurs between the saprolite and bedrock
and contains saprolite and rock remnants. This unit was described as white to reddish
yellow to olive brown to dark gray with quartz and potassium feldspar fragments.
• Bedrock – Bedrock was encountered in borings completed around the western,
southern, and eastern extents of the ash basin. Depth to top of bedrock ranged from 10
to 108 feet below ground surface. Bedrock was described as granite, quartzite, and
gabbro.
Hydraulic conductivity in these hydrostratigraphic units can vary, but is generally thought to fall
within the ranges provided in the table below where Kh refers to hydraulic conductivity in the
horizontal direction and Kv refers to hydraulic conductivity in the vertical direction:
Hydrostratigraphic Unit Range of k Values (cm/sec)
Fill (Kh)2 1.0E-06 to 1.0E-04
Ash (Kh)1,3 1.0E-06 to 1.0 E-04
Ash (Kv)4 2.8E-05 to 1.17E-04
Alluvium (Kh)1,3 1.31E-06 to 2.72E-03
Residual Soil/Saprolite (Kh)1,3 9.67E-07 to 1.79E-02
Partially Weathered/ Fractured Rock –
TZ (Kh)1,3 1.92E-06 to 3.3E-02
Bedrock (Kh)1,3 1.78E-07 to 9.89E-03
Notes:
1. Data from in-situ permeability tests at ash basins located within the Carolina Piedmont.
2. Estimates for F (fill) based on data that indicates the ‘k’ for fill is about an order of magnitude lower than the in-situ
material used for the fill (after compaction).
3. Hydraulic Conductivity Database - HDR (unpublished data).
4. Hydraulic Conductivity data from site-specific laboratory testing of Shelby tube samples from Buck Steam Station (HDR
2014C)
5. Data from in-situ permeability tests at ash basins located within the Carolina Piedmont.
As the site is located in the Piedmont, it is anticipated that the groundwater flow will be primarily
in the saprolite and the transition zone material with flow also occurring in the fractured or
weathered zones in bedrock. The sampling and testing proposed in Section 7 will provide
additional information on the transport characteristics of the materials at the site.
Groundwater flow and transport at the Allen site are assumed to follow the local slope aquifer
system as described by LeGrand (2004). Under natural conditions, the general direction of
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Allen Steam Station Ash Basin
5.0 Initial Conceptual Site Model
groundwater flow can be approximated from the surface topography. The station’s ash basin is
situated between the Allen station to the north and topographic divides to the west (along South
Point Road) and south (along Reese Wilson Road). The topographic divide along South Point
Road likely functions as a groundwater divide. The topography at the site generally slopes
downward from the west toward Lake Wylie. The predominant direction of groundwater flow
from the ash basin is likely in an easterly direction, generally toward Lake Wylie.
Groundwater recharge in the Piedmont is derived entirely from infiltration of local precipitation.
Groundwater recharge occurs in areas of higher topography (i.e., hilltops) and groundwater
discharge occurs in lowland areas bordering surface water bodies, marshes, and floodplains
(LeGrand 2004). At the Allen site, groundwater recharge is expected to occur on the
northwestern, western, and southern portions of the site where topography is higher.
Groundwater is expected to discharge into Lake Wylie to the east.
Following completion of the groundwater assessment work, a site conceptual model will be
developed as described in Section 7.5.
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6.0 Compliance Groundwater Monitoring
6.0 Compliance Groundwater Monitoring
As described in Section 2.3, groundwater monitoring is required as a condition of the NPDES
permit. From March 2011 through November 2014, the compliance groundwater monitoring
wells at Allen have been sampled a total of 12 times. During this period, these monitoring wells
were sampled in:
• March 2011
• July 2011
• November 2011
• March 2012
• July 2012
• November 2012
• March 2013
• July 2013
• November 2013
• March 2014
• July 2014
• November 2014
With the exception of boron, iron, manganese, pH, and nickel, the results for all monitored
parameters and constituents were less than the 2L Standards. Table 3 lists the range of
exceedances for boron, iron, manganese, pH, and nickel for the period of March 2011 through
November 2014.
All available groundwater quality data for compliance monitoring wells and voluntary monitoring
wells (as mentioned above and shown on Figure 2) are summarized in Table 7. Historical
analytical data for surface water samples, ash samples, ash leachate samples, and landfill
leachate samples were provided by Duke Energy. Surface water quality data for samples
collected from the ash basin is provided in Table 8. Ash quality data for samples collected from
ash placed in the structural fill and RAB Landfill is provided in Table 9. Ash leachate quality data
for samples collected from the ash basin is provided in Table 10. Leachate quality data for
samples collected from the RAB landfill leachate management system is provided in Table 11.
In addition, seep analytical results from the August 2014 seep sampling (as part of Duke
Energy’s NPDES permit renewal application) are provided in Table 12.
Compliance groundwater monitoring will continue as scheduled in accordance with the
requirements of the NPDES permit.
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7.0 Assessment Work Plan
7.0 Assessment Work Plan
Solid and aqueous media sampling will be performed to provide information pertaining to the
horizontal and vertical extent of potential soil and groundwater contamination and to determine
physical properties of the ash and soil. Based on readily available site background information
and dependent upon accessibility, HDR anticipates collecting the following samples as part of
the subsurface exploration plan:
• Ash and soil samples from borings within and beneath the ash basin
• Soil samples from borings located outside the ash basin boundary
• Groundwater samples from proposed monitoring wells
• Groundwater samples from select existing compliance and/or voluntary monitoring wells
• Groundwater samples from two existing onsite water supply wells
• Surface water samples from water bodies located within the ash basin waste boundary
• Seep samples from locations identified as part of Duke Energy’s NPDES permit renewal
application (from August 2014)
In addition, hydrogeologic evaluation testing will be conducted during and following monitoring
well installation activities as described in Section 7.1.6. Existing groundwater quality data from
compliance monitoring wells and voluntary monitoring wells will be used to supplement data
obtained from this assessment work.
A summary of the proposed exploration plan including estimated sample quantities and
estimated depths of soil borings and monitoring wells is presented in Table 4. The proposed
sampling locations are shown on Figure 3.
Groundwater samples collected from existing ash basin compliance monitoring wells AB-4S,
AB-12S, AB-12D, AB-13S, AB-13D, and AB-14D are located at or close to the Duke Energy
property boundary and have shown exceedances of 2L Standards. These exceedances have
primarily consisted of iron and/or manganese, with nickel exceedances limited to monitoring well
AB-14D from 2011 through 2013. Upon approval of the work plan, HDR proposes to perform an
evaluation of these exceedances with respect to turbidity and to naturally occurring background
conditions. If that evaluation finds the exceedances are caused by turbidity, the well(s) will be
redeveloped and replaced, if required, as described in Section 7.2.1. If the evaluation finds that
the exceedances are not caused by turbidity or naturally occurring conditions, then additional
monitoring wells will be installed to delineate the extent of the exceedances. The proposed
potential locations would not be located on Duke Energy property and would require permission
from the adjacent property owners. The proposed potential locations of these wells are shown
on Figure 3. The installation depths of the well screens will be determined based on site
conditions and the depth of the compliance wells with the exceedance.
If it is determined that additional investigations are required during the review of existing data or
data developed from this assessment, Duke Energy will notify the NCDENR regional office prior
to initiating additional sampling or investigations.
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7.1 Subsurface Exploration
Characterization of subsurface materials will be conducted through the completion of soil
borings and borings performed for installation of monitoring wells as shown on Figure 3.
Installation details for soil borings and monitoring wells, as well as estimated sample quantities
and depths, are described below and presented in Table 4.
For nested monitoring wells, the deep monitoring well boring will be utilized for characterization
of subsurface materials and collection of samples for laboratory analysis. Shallow, deep, and
bedrock monitoring well borings will be logged in the field as described below.
At the conclusion of well installation activities, well construction details including casing depth;
total well depth; and well screen length, slot size, and placement within specific
hydrostratigraphic units will be presented in tabular form for inclusion into the final CSA Report.
Well completion records will be submitted to NCDENR within 30 days of completion.
Duke Energy acknowledges that subsurface geophysics may be useful for evaluation of
subsurface conditions in areas of the site that have not been significantly reworked by
construction or ash management activities, but less useful in basins and fills. Subsequent to
evaluation of field data obtained during the proposed investigation activities, Duke Energy will
evaluate the need for and potential usefulness of subsurface geophysics in select areas of the
site. If it is determined that subsurface investigation is warranted, Duke Energy and HDR will
notify the NCDENR regional office prior to initiating additional investigations.
7.1.1 Ash and Soil Borings
Characterization of ash and underlying soil will be accomplished through the completion and
sampling of borings advanced at 9 monitoring well locations within the active ash basin and on
the north and east dikes (designated as AB-20 through AB-28), 11 monitoring well locations
within the inactive ash basin and on the east dike (designated as AB-29 through AB-39), 6 soil
boring locations in the west portion of the inactive ash basin (designated as SB-1 through SB-6),
and 3 soil boring locations in the active ash basin area (SB-7 through SB-9). In addition, 12 soil
borings (designated as GWA-1 through GWA-9 and BG-1 through BG-3) will be completed
outside of ash management areas to provide additional soil quality data.
Note that Duke Energy will notify the Division of Waste Management (DWM) prior to installing
proposed borings/monitoring wells located adjacent to the RAB Ash Landfill (designated as
AB-29S/D through AB-34S/D) and within and adjacent to the structural fill area (designated as
SB-4, SB-5, SB-6, AB-35S/D/BR, and AB-39S/D). No borings will be advanced within the
footprint of the double-lined ash landfill located in the east portion of the inactive ash basin.
Field data collected during boring advancement will be used to evaluate:
• the presence or absence of ash
• areal extent and depth/thickness of ash
• groundwater flow and transport characteristics if groundwater is encountered
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Borings will be advanced using hollow stem auger or roller cone drilling techniques to facilitate
collection of down-hole data. Standard Penetration Testing (SPT) (ASTM D 1586) and split-
spoon sampling will be performed at 5-foot increments using an 18-inch split-spoon sampler.
Soil borings located within the waste boundary that will not be used for installation of monitoring
wells (SB-1 through SB-9) will extend approximately 20 feet below the ash/native soil interface
or to refusal, whichever is encountered first. Note that continuous coring will be performed from
auger refusal to a depth of at least 50 feet into competent bedrock for bedrock monitoring well
borings (designated as BR soil boring/groundwater monitoring well locations on Figure 3).
Borings will be logged and ash/soil samples will be photographed, described, and visually
classified in the field for origin, consistency/relative density, color, and soil type in accordance
with the Unified Soil Classification System (ASTM D2487/D2488).
BORINGS WITHIN ASH BASIN WASTE BOUNDARY
In areas where ash is known or suspected to be present (i.e., AB- and S-borings), solid phase
samples will be collected for laboratory analysis from the following intervals in each boring:
• Shallow Ash – approximately 3 feet to 5 feet bgs
• Deeper Ash – approximately 2 feet above the ash/soil interface
• Upper Soil – approximately 2 feet below the ash/soil interface
• Deeper Soil – approximately 8 feet to 10 feet below the ash/soil interface
If ash is observed to be greater than 30 feet thick, a third ash sample will be collected from the
approximate mid-point depth between the shallow and deeper samples. The ash samples will
be used to evaluate geochemical variations in ash located in the ash basin and ash storage.
The upper and deeper soil samples will be used to delineate the vertical extent of potential soil
impacts beneath the ash basin and ash storage.
Ash and soil samples will be analyzed for total inorganic compounds as presented in Table 5.
Select ash samples will be analyzed for leachable inorganic compounds using the Synthetic
Precipitation Leaching Procedure (SPLP) to evaluate the potential for leaching of constituents
from ash into underlying soil. The ash SPLP analytical results will be compared to Class GA
Standards as found in 15A NCAC 02L .0202 Groundwater Quality Standards, last amended on
April 1, 2013 (2L Standards).
Ash is located at varying depths beneath the ponded water areas within the active ash basin.
Due to safety concerns, borings will not be completed where ponded water is present within the
ash basin. Safety concerns may also prevent access to proposed boring locations on ash areas
where saturated ash presents stability issues.
BORINGS OUTSIDE ASH BASIN WASTE BOUNDARY
Borings located outside the ash basin waste boundary are designated as GWA and BG borings.
The GWA soil samples will be used to provide additional characterization of soil conditions
outside the ash basin boundary. Solid phase samples will be collected for laboratory analysis
from the following intervals in each boring:
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• Approximately 2 feet to 3 feet above the water table
• Approximately 2 feet to 3 feet below the water table
• Within the saturated upper transition zone material (if not already included in the two
sample intervals above)
• From a primary, open, stained fracture within fresh bedrock if existent (bedrock core
locations only)
The boring locations designated as BG borings will be used to evaluate site-specific background
soil quality. Solid phase samples will be collected for laboratory analysis from the following
intervals in each boring:
• At approximately 10-foot intervals until reaching the water table (i.e., 0 feet to 2 feet, 10
feet to 12 feet, 20 feet to 22 feet, and so forth)
• Approximately 2 feet to 3 feet above the water table
• Approximately 2 feet to 3 feet below the water table
• Within the saturated upper transition zone material (if not already included in the two
sample intervals above)
• From a primary, open, stained fracture within fresh bedrock if existent (bedrock core
locations only)
The laboratory analyses performed on the GWA and BG samples will depend on the nature and
quantity of material collected.
One or more of the above listed sampling intervals may be combined if field conditions indicate
they are in close proximity to each other (i.e., one sample will be obtained that will be applicable
to more than one interval).
INDEX PROPERTY SAMPLING AND ANALYSES
In addition, physical properties of ash and soil will be tested in the laboratory to provide data for
use in groundwater modeling. Split-spoon samples will be collected at selected locations with
the number of samples collected from the material types as follows:
• Fill - 5 samples
• Ash - 5 samples
• Alluvium - 5 samples
• Soil/Saprolite - 5 samples
• Soil/Saprolite - immediately above refusal - 5 samples
Select split-spoon samples will be tested for:
• Natural Moisture Content Determination in accordance with ASTM D-2216
• Grain size with hydrometer determination in accordance with ASTM Standard D-422
The select split-spoon samples are anticipated to be collected from the following boring
locations:
• Fill – AB-22S/D, AB-26S/D, AB-28S/D, AB-31S/D, and AB-32S/D
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• Ash – AB-21S/D, AB-25S/D, AB-29S/D, AB-34S/D, AB-37S/D, and SB-3
• Alluvium (if present) – GWA-3S/D (2 samples), GWA-4S/D, and GWA-5S/D (2 samples)
• Soil/Saprolite (two locations each as stated above) – BG-2S/D/BR, GWA-1S/D,
GWA-3S/D, GWA-6S/D, and AB-35S/D/BR
The depth intervals of the select split-spoon samples will be determined in the field by the Lead
Geologist/Engineer.
In addition to split-spoon sampling, a minimum of five thin-walled undisturbed tubes (“Shelby”
Tubes) in fill, ash, and soil/saprolite layers will be collected from the above-referenced boring
locations. Sample depths will be determined in the field based on conditions encountered during
borehole advancement. The Shelby Tubes will be transported to a soil testing laboratory and
each tube will be tested for the following:
• Natural Moisture Content Determination in accordance with ASTM D-2216
• Grain size with hydrometer determination in accordance with ASTM Standard D-422
• Hydraulic Conductivity Determination in accordance with ASTM Standard D-5084
• Specific Gravity of Soils in accordance with ASTM Standard D-854
The results of the laboratory soil and ash property determination will be used to determine
additional soil properties such as porosity, transmissivity, and specific storativity. The results
from these tests will be used in the groundwater fate and transport modeling. The specific
borings where these samples are collected from will be determined based on field conditions
with consideration given to their location relative to use in the groundwater model.
7.1.2 Shallow Monitoring Wells
SHALLOW MONITORING WELLS IN REGOLITH
Groundwater quality and flow characteristics within the regolith aquifer will be evaluated through
the installation, sampling, and testing of 16 shallow monitoring wells at the locations specified
on Figure 3 with an “S” qualifier in the well name (e.g., GWA-1S). Shallow monitoring wells are
defined as wells that are screened wholly within the regolith zone or ash and set to bracket the
water table surface at the time of installation.
Shallow monitoring wells will be installed using hollow stem auger or roller cone drilling
techniques. At each monitoring well location, a shallow well will be constructed with a 2-inch-
diameter, Schedule 40 polyvinyl chloride (PVC) screen and casing. Each of these wells will
have a 10-foot to 15-foot pre-packed well screen having manufactured 0.010-inch slots
In the event that the regolith zone is found to be relatively thick at a particular well location and
that more than one discreet flow zone is observed during drilling (e.g., presence of confining
unit), a second shallow monitoring well will be installed to provide groundwater flow and quality
data for upper and lower flow zones. In these instances, the wells installed into the lower flow
zones will be designated with an “SL” identifier to differentiate between the upper and lower
shallow wells located in the regolith zone.
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SHALLOW MONITORING WELLS IN DAMS
Groundwater quality and flow characteristics of the phreatic surface within ash basin dams not
founded on ash will be evaluated through the installation, sampling, and testing of shallow
monitoring wells at locations on the East Dike, specified on Figure 3 with an “S” qualifier in the
well name (e.g., AB-22S). Wells will be installed with 10-foot to15-foot screens set to bracket the
phreatic surface at the time of installation.
Shallow monitoring wells will be installed using hollow stem auger or roller cone drilling
techniques. At each monitoring well location, a shallow well will be constructed with a 2-inch-
diameter, Schedule 40 PVC screen and casing. Each of these wells will have a 10-foot to
15-foot pre-packed well screen having manufactured 0.010-inch slots.
SHALLOW MONITORING WELLS IN ASH BASIN POREWATER
The water quality and flow characteristics within the ash basin porewater will be evaluated
through the installation, sampling, and testing of 20 porewater wells at the locations specified on
Figure 3. Wells designated as “S” will be installed with 10-foot to15-foot screens with the well
screen set to bracket the water table surface at the time of installation. Wells designated as “SL”
will be installed with the bottom of the well screen set above the ash-regolith interface and will
be installed with 10-foot screens.
These wells will be installed using hollow stem auger or roller cone drilling techniques. The wells
will be constructed with 2-inch-diameter, Schedule 40 PVC screen and casing. These wells will
be installed with pre-packed well screens having manufactured 0.010-inch slots.
7.1.3 Deep Monitoring Wells
Groundwater quality and flow characteristics within the transition zone (if present) will be
evaluated through the installation, sampling, and testing of 32 deep monitoring wells at the
locations specified on Figure 3 with a “D” qualifier in the well name (e.g., GWA-1D). Deep
monitoring wells are defined as wells that are screened within the partially weathered/fractured
bedrock transition zone at the base of the regolith.
Deep monitoring wells will be installed using hollow stem augers and rock coring drilling
techniques. At each deep monitoring well location, a double-cased well will be constructed with
a 6-inch-diameter PVC outer casing and a 2-inch-diameter PVC inner casing and well screen.
The purpose of installing cased wells at the site is to prevent possible cross-contamination of
flow zones within the shallow and deeper portions of the unconfined aquifer during well
installation. Outer well casings (6-inch casing) will be advanced to auger refusal and set
approximately 1 foot into PWR (if present). Note that location-specific subsurface geology will
dictate actual casing depths on a per-well basis. The annulus between the borehole and casing
will be grouted to the surface using the tremie grout method. After the grout has been allowed to
cure for a period of 24 hours, the borehole will be extended via coring approximately 10 feet to
15 feet into transition zone rock using an HQ core barrel. A 2-inch-diameter well with a 5-foot
pre-packed well screen will be set at least 2 feet below the bottom of the outer casing.
If the PWR thickness is determined to be greater than 30 feet thick at a nested well location,
additional wells in the transition zone will be considered based on site-specific conditions.
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Rock cores will be logged in accordance with the Field Guide for Rock Core Logging and
Fracture Analysis by Midwest GeoSciences Group. Percent recovery and rock quality
designation (RQD) will be calculated in the field. The cores will be photographed and retained.
7.1.4 Bedrock Monitoring Wells
Groundwater quality and flow within fractured bedrock beneath the site will be evaluated
through the installation, sampling, and testing of 5 bedrock monitoring wells at the locations
specified on Figure 3 with a “BR” qualifier in the name (e.g., GWA-1BR). Bedrock monitoring
wells are defined as wells that are screened across water-bearing fractures wholly within fresh,
competent bedrock.
At these locations, continuous coring will be performed from auger refusal to a depth of at least
50 feet into competent bedrock. Packer testing will be performed on select fractures observed in
the rock cores. See Section 7.1.6 for details regarding packer test implementation.
Water source(s) to be used in rock coring and packer testing will be sampled for all constituents
included in Table 6 before use.
Rock cores will be logged in accordance with the Field Guide for Rock Core Logging and
Fracture Analysis by Midwest GeoSciences Group. Percent recovery and RQD will be
calculated in the field. The cores will be photographed and retained.
At each of these locations, a double-cased well will be constructed with a 6-inch-diameter PVC
outer casing and a 2-inch-diameter PVC inner casing and well screen. Outer well casings will be
advanced through the transition zone and set approximately 1 foot into competent bedrock. The
annulus between the borehole and casing will be grouted to the surface using the tremie grout
method. After the grout has been allowed to cure for a period of 24 hours, the borehole will be
extended via coring approximately 50 feet into competent bedrock using an HQ core barrel. A 2-
inch-diameter well with a 5-foot pre-packed well screen will be set at depth across an
interpreted water-bearing fracture or fracture zone based on the results of packer testing. Note
that location-specific subsurface geology will dictate actual casing depths and screen placement
on a per-well basis.
7.1.5 Well Completion and Development
WELL COMPLETION DETAILS
As described above, pre-packed screens will be installed around the monitoring well screens to
reduce turbidity during sample collection. The pre-packed screens will consist of environmental
grade sand contained within a stainless steel wire mesh cylinder. The sand gradation in the pre-
packed screen will be made in advance anticipating a wide range of site conditions; however,
HDR believes that the sand will typically be 20/40 mesh silica sand. The Geologist/Engineer
involved with the specific installation will evaluate field conditions and determine if changes are
required. A minimum one to two-foot-thick bentonite seal hydrated with potable water will be
placed above the pre-packed screen. Cement grout will be placed in the annular space between
the PVC casing and the borehole above the bentonite seal and extending to the ground surface.
Each well will be finished at the ground surface with a 2-foot square concrete well pad and new
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4-inch or 8-inch steel above-grade lockable covers. Following completion, all wells will be locked
with a keyed pad lock.
WELL DEVELOPMENT
All newly installed monitoring wells will be developed to create an effective filter pack around the
well screen and to remove fine particles within the well from the formation near the borehole.
Based on site-specific conditions per 15A NCAC 02C .0108(p), appropriate measures (e.g.,
agitation, surging, pumping, etc.) will be utilized to stress the formation around the screen and
the filter pack so that mobile fines, silts, and clays are pulled into the well and removed.
Water quality parameters (specific conductance, pH, temperature, oxidation reduction potential
[ORP], and turbidity) will be measured and recorded during development and should stabilize
before development is considered complete. Development will continue until development water
is visually clear (< 10 Nephelometric Turbidity Units [NTU] Turbidity) and sediment free.
If a well cannot be developed to produce low turbidity (< 10 NTU) groundwater samples),
NCDENR will be notified and supplied with the well completion and development measures that
have been employed to make a determination if the turbidity is an artifact of the geologic
materials in which the well is screened.
Following development, sounding the bottom of the well with a water level meter should indicate
a “hard” (sediment-free) bottom. Development records will be prepared under the direction of
the Project Scientist/Engineer and will include development method(s), water volume removed,
and field measurements of temperature, pH, conductivity, and turbidity.
7.1.6 Hydrogeologic Evaluation Testing
In order to better characterize hydrogeologic conditions at the site, falling and constant head
tests, packet tests, and slug tests will be performed as described below. Data obtained from
these tests will be used in groundwater modeling. In addition, historical soil boring data at the
site will be utilized as appropriate to better characterize hydrogeologic conditions and will be
used for groundwater modeling. All water meters, pressure gages, and pressure transducers
will be calibrated per specifications for testing.
FALLING/CONSTANT HEAD TESTS
A minimum of five in-situ borehole horizontal permeability tests, either falling or constant head
tests, will be performed just below refusal in the upper bedrock (transition zone if present). In
each of the hydrostratigraphic units above refusal; ash, fill, alluvium, and soil/saprolite (if
present), a minimum of ten falling and constant head tests (five for vertical permeability and five
for horizontal permeability) will be performed. The tests will be at locations based on
site-specific conditions at the time of assessment work. The U.S. Bureau of Reclamation (1995)
test method and calculation procedures as described in Chapter 10 of their Ground Water
Manual (2nd Edition) will be used.
PACKER TESTS
A minimum of five packer tests using a double packer system will be performed in deep
well/transition zone borings at locations based on site-specific conditions, as well as a minimum
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of one packer test in each soil/rock core well boring as described in Section 7.1.4 after
completion of the holes. Packer tests will utilize a double packer system and the interval (5 or 10
feet based on field conditions) to be tested will be based on observation of the rock core and will
be selected by the Lead Geologist/Engineer. The U.S. Bureau of Reclamation (1995) test
method and calculation procedures as described in Chapter 10 of their Ground Water Manual
(2nd Edition) will be used.
SLUG TESTS
Hydraulic conductivity (slug) tests will be completed in all installed monitoring wells under the
direction of the Lead Geologist/Engineer. Slug tests will be performed to meet the requirements
of the NCDENR Memorandum titled “Performance and Analysis of Aquifer Slug Tests and
Pumping Tests Policy” dated May 31, 2007. Water level change during the slug tests will be
recorded by a data logger. The slug test will be performed for no less than 10 minutes or until
such time as the water level in the test well recovers 95 percent of its original pre-test level,
whichever occurs first. Slug tests will be terminated after 2 hours even if the 95 percent pre-test
level is not achieved. Slug test field data will be analyzed using the Aqtesolv (or similar)
software using the Bouwer and Rice method.
7.2 Groundwater Sampling and Analysis
Subsequent to monitoring well installation and development, each newly installed well will be
sampled using low-flow sampling techniques in accordance with USEPA Region 1 Low Stress
(low flow) Purging and Sampling Procedure for the Collection of Groundwater Samples from
Monitoring Wells (revised January 19, 2010). The purposes of the proposed monitoring wells
are as follows:
• AB-series Wells –The AB-series well locations were selected to provide water quality
data in and beneath the active ash basin
• GWA-series Wells – The GWA-series well locations were selected to provide water
quality data beyond the ash basin waste boundary for use in groundwater modeling (i.e.,
to evaluate the horizontal and vertical extent of potentially impacted groundwater outside
the ash basin waste boundary)
• BG-series Wells – These wells will be used to provide information on background water
quality. The background well locations were selected to provide additional physical
separation from possible influence of the ash basin on groundwater. These wells will
also be useful in the statistical analysis to determine the site-specific background water
quality concentrations (SSBCs).
During low-flow purging and sampling, groundwater is pumped into a flow-through chamber at
flow rates that minimize or stabilize water level drawdown within the well. Indicator parameters
are measured over time (usually at 5-minute intervals). When parameters have stabilized within
±0.2 pH units and ±10 percent for temperature, conductivity, and dissolved oxygen (DO), and
±10 millivolts (mV) for oxidation reduction potential (ORP) over three consecutive readings,
representative groundwater has been achieved for sampling. Turbidity levels of 10 NTU or less
will be targeted prior to sample collection. Purging will be discontinued and groundwater
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samples will be obtained if turbidity levels of 10 NTU or less are not obtained after 2 hours of
continuous purging. Groundwater samples will be analyzed by a North Carolina certified
laboratory for the constituents included in Table 6. Select constituents will be analyzed for total
and dissolved concentrations.
In 2014, the Electric Power Research Institute published the results of a critical review that
presented the current state-of-knowledge concerning radioactive elements in CCPs and the
potential radiological impacts associated with management and disposal. The review found:
Despite the enrichment of radionuclides from coal to ash, this critical review did not
locate any published studies that suggested typical CCPs posed any significant
radiological risks above background in the disposal scenarios considered, and when
used in concrete products. These conclusions are consistent with previous
assessments. The USGS (1997) concluded that “Radioactive elements in coal and fly
ash should not be sources of alarm. The vast majority of coal and the majority of fly ash
are not significantly enriched in radioactive elements, or in associated radioactivity,
compared to common soils or rocks.” A year later, the U.S. EPA (1998) concluded that
the risks of exposure to radionuclide emissions from electric utilities are “substantially
lower than the risks due to exposure to background radiation.”
Duke Energy proposes to sample voluntary monitoring well AB-8 and the proposed background
wells BG-3S/D for total combined radium (Ra-226 and Ra-228) and will consult with the DWR
regional office to determine if additional wells are to be sampled.
Groundwater sample results will be compared to Class GA Standards as found in 15A NCAC
02L .0202 Groundwater Quality Standards, last amended on April 1, 2013 (2L Standards).
Redox conditions are not likely to be strong enough to produce methane at the site; therefore,
methane was not included in the constituent list (Table 6).
7.2.1 Existing Compliance and Voluntary Monitoring Wells
Groundwater samples will be collected from selected existing voluntary and/or compliance
monitoring wells. Prior to collecting groundwater samples from the existing voluntary and/or
compliance monitoring wells, the historical turbidity values at each of the wells will be evaluated.
For wells where turbidity levels have historically been greater than 10 NTUs, these wells will be
re-developed as described above prior to collecting groundwater samples. If redevelopment
does not result in reduced turbidity, the well(s) will be replaced. The DWR regional office will be
contacted prior to replacing a compliance monitoring well.
7.2.2 Onsite Water Supply Wells
Groundwater samples will be collected from two existing onsite water supply wells using the
pumping systems installed in the well. The water supply wells will be purged for a minimum of
15 minutes prior to collection of a sample. Water samples will be collected prior to any filtration
system. The groundwater samples collected from the onsite water supply wells will be analyzed
for the constituents included in Table 6.
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7.2.3 Speciation of Select Inorganics
In addition to total analytes, speciation of select inorganics will be conducted for select sample
locations to characterize the aqueous chemistry and geochemistry in locations and depths of
concern. Speciation of iron (Fe(II), Fe(III)) and manganese (Mn(II), Mn(IV)) will be conducted in
pore water samples collected from upper and lower elevations of ash within the basin and in
groundwater samples collected from wells outside and downgradient of the ash basin.
Specifically, Duke Energy proposes to speciate iron and manganese in pore water samples
collected from proposed wells AB-21S/SL/D, AB-25S/SL/D and AB-29S/SL/D, in groundwater
samples collected from compliance wells AB-1R, AB-4S, AB-9S/D and AB-10S/D, and in
groundwater samples collected from proposed wells BG-2S/D and GWA-3S/D. Laboratory
analyses will be performed in accordance with the methods provided in Table 6.
7.3 Surface Water and Seep Sampling
7.3.1 Surface Water Samples
There are no surface waters located in the anticipated groundwater flow direction at the site
between the ash basin and Lake Wylie. Therefore, no surface waters are proposed outside of
the ash basin.
WITHIN ASH BASIN
Surface water samples will be collected from the active ash basin at the approximate open
water locations shown on Figure 3 (SW -1 through SW -4). At each location, two water samples
will be collected – one sample close to the surface (i.e., 0 foot to 1 foot from surface) and one
sample at the approximate middle depth of the water body. Prior to sampling, the depth to ash
will be measured by slowly lowering a measuring stick or tape until the ash surface is
encountered, being careful to avoid suspending the ash. The depth to ash will be noted and a
sample thief will be slowly lowered to the desired depth to collect the sample. The sample thief
and sample will be retrieved and the sample will be transferred to the appropriate sample
containers provided by the laboratory. The middle depth sample will vary based on the water
level in the water body. In areas where the water body is less than 5 feet deep, one water
sample will be collected from the location at the approximate middle depth of the water body.
Ash basin surface water samples will be analyzed for the same constituents as groundwater
samples (Table 6). Select constituents will be analyzed for total and dissolved concentrations.
7.3.2 Seep Samples
Water samples will be collected from the seep sample locations shown on Figure 3 (S-1 through
S-9). The seep samples will be analyzed for the same constituents as groundwater samples
(Table 6). Select constituents will be analyzed for total and dissolved concentrations.
Water samples were previously collected from seep sample locations S-1 through S-9 in
September 2014 as part of Duke Energy’s NPDES permit renewal application package. The
analytical results indicated exceedances of 2B Standards for several constituents: boron, iron,
manganese, zinc, and thallium. Duke Energy collects surface water samples from Lake Wylie
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from upstream and downstream locations for their existing NPDES permit requirements. If seep
sample analytical results indicate potential for impacts to Lake Wylie, then surface water quality
data collected in Lake Wylie will be reviewed.
In March 2014, DENR conducted seep sampling at the site. HDR does not currently have the
analytical results from this sampling event; however, once data is received, HDR will review the
data and determine if changes to the proposed seep locations are needed.
Analytical results from the seep sampling will be reviewed to determine if similar speciation
analyses as described in Section 7.2.3 are to be performed for selected seep locations.
After analytical results for seep samples are reviewed, a determination will be made concerning
collection of additional off-site seep samples. If it is determined that additional off site seep
samples are to be collected, the DWR regional office will be contacted.
7.3.3 Sediment Samples
Sediment samples will be collected from the bed of the seep samples at the locations shown on
Figure 3 (designated as S-1 through S-9) in conjunction with collection of the seep samples.
The sediment samples will be analyzed for total inorganics using the same constituents list
proposed for soil and ash samples (Table 5).
7.4 Field and Sampling Quality Assurance/Quality Control
Procedures
Documentation of field activities will be completed using a combination of logbooks, field data
records (FDRs), sample tracking systems, and sample custody records. Site and field logbooks
are completed to provide a general record of activities and events that occur during each field
task. FDRs have been designated for each exploration and sample collection task to provide a
complete record of data obtained during the activity.
7.4.1 Field Logbooks
The field logbooks provide a daily hand written account of field activities. Logbooks are
hardcover books that are permanently bound. All entries are made in indelible ink, and
corrections are made with a single line with the author initials and date. Each page of the
logbook will be dated and initialed by the person completing the log. Partially completed pages
will have a line drawn through the unused portion at the end of each day with the author’s
initials. The following information is generally entered into the field logbooks:
• The date and time of each entry. The daily log generally begins with the Pre-Job Safety
Brief.
• A summary of important tasks or subtasks completed during the day
• A description of field tests completed in association with the daily task
• A description of samples collected including documentation of any quality control
samples that were prepared (rinse blanks, duplicates, matrix spike, split samples, etc.)
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• Documentation of equipment maintenance and calibration activities
• Documentation of equipment decontamination activities
• Descriptions of deviations from the work plan
7.4.2 Field Data Records
Sample FDRs contain sample collection and/or exploration details. A FDR is completed each
time a field sample is collected. The goal of the FDR is to document exploration and sample
collection methods, materials, dates and times, and sample locations and identifiers. Field
measurements and observations associated with a given exploration or sample collection task
are recorded on the FDRs. FDRs are maintained throughout the field program in files that
become a permanent record of field program activities.
7.4.3 Sample Identification
In order to ensure that each number for every field sample collected is unique, samples will be
identified by the sample location and depth interval, if applicable (e.g., MW -11S (5-6’). Samples
will be numbered in accordance with the proposed sample IDs shown on Figure 3.
7.4.4 Field Equipment Calibration
Field sampling equipment (e.g., water quality meter) will be properly maintained and calibrated
prior to and during continued use to ensure that measurements are accurate within the
limitations of the equipment. Personnel will follow the manufacturers’ instructions to determine if
the instruments are functioning within their established operation ranges. The calibration data
will be recorded on a FDR.
To be acceptable, a field test must be bracketed between acceptable calibration results.
• The first check may be an initial calibration, but the second check must be a continuing
verification check
• Each field instrument must be calibrated prior to use
• Verify the calibration at no more than 24-hour intervals during use and at the end of the
use if the instrument will not be used the next day or time periods greater than 24 hours
• Initial calibration and verification checks must meet acceptance criteria
• If an initial calibration or verification check fails to meet acceptance criteria, immediately
recalibrate the instrument or remove it from service
• If a calibration check fails to meet the acceptance criteria and it is not possible to
reanalyze the samples, the following actions must be taken:
- Report results between the last acceptable calibration check and the failed
calibration check as estimated (qualified with a “J”)
- Include a narrative of the problem
- Shorten the time period between verification checks or repair/replace the instrument
• If historically generated data demonstrate that a specific instrument remains stable for
extended periods of time, the interval between initial calibration and calibration checks
may be increased
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- Acceptable field data must be bracketed by acceptable checks. Data that are not
bracketed by acceptable checks must be qualified
- Base the selected time interval on the shortest interval that the instrument maintains
stability
- If an extended time interval is used and the instrument consistently fails to meet the
final calibration check, then the instrument may require maintenance to repair the
problem or the time period is too long and must be shortened
• For continuous monitoring equipment, acceptable field data must be bracketed by
acceptable checks or the data must be qualified
Sampling or field measurement instrument determined to be malfunctioning will be repaired or
will be replaced with a new piece of equipment.
7.4.5 Sample Custody Requirements
A program of sample custody will be followed during sample handling activities in both field and
laboratory operations. This program is designed to ensure that each sample is accounted for at
all times. The appropriate sampling and laboratory personnel will complete sample FDRs, chain-
of -custody records, and laboratory receipt sheets.
The primary objective of sample custody procedures is to obtain an accurate written record that
can trace the handling of all samples during the sample collection process, through analysis,
until final disposition.
FIELD SAMPLE CUSTODY
Sample custody for samples collected during each sampling event will be maintained by the
personnel collecting the samples. Each sampler is responsible for documenting each sample
transfer, maintaining sample custody until the samples are shipped off site, and sample
shipment. The sample custody protocol followed by the sampling personnel involves:
• Documenting procedures and amounts of reagents or supplies (e.g., filters) which
become an integral part of the sample from sample preparation and preservation
• Recording sample locations, sample bottle identification, and specific sample acquisition
measures on appropriate forms
• Using sample labels to document all information necessary for effective sample tracking
• Completing sample FDR forms to establish sample custody in the field before sample
shipment
Prepared labels are normally developed for each sample prior to sample collection. At a
minimum, each label will contain:
• Sample location and depth (if applicable)
• Date and time collected
• Sampler identification
• Analyses requested and applicable preservative
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A manually prepared chain-of -custody record will be initiated at the time of sample collection.
The chain-of-custody record documents:
• Sample handling procedures including sample location, sample number, and number of
containers corresponding to each sample number
• The requested analysis and applicable preservative
• The dates and times of sample collection
• The names of the sampler(s) and the person shipping the samples (if applicable)
• The date and time that samples were delivered for shipping (if applicable)
• Shipping information (e.g., FedEx Air Bill)
• The names of those responsible for receiving the samples at the laboratory
Chain-of-custody records will be prepared by the individual field samplers.
SAMPLE CONTAINER PACKING
Sample containers will be packed in plastic coolers for shipment or pick up by the laboratory.
Bottles will be packed tightly to reduce movement of bottles during transport. Ice will be placed
in the cooler along with the chain-of-custody record in a separate, resealable, air tight, plastic
bag. A temperature blank provided by the laboratory will also be placed in each cooler prior to
shipment if required for the type of samples collected and analyses requested.
7.4.6 Quality Assurance and Quality Control Samples
The following Quality Assurance/Quality Control (QA/QC) samples will be collected during the
proposed field activities:
• Equipment rinse blanks (one per day)
• Field Duplicates (one per 20 samples per sample medium)
Equipment rinse blanks will be collected from non-dedicated equipment used between wells and
from drilling equipment between soil samples. The field equipment is cleaned following
documented cleaning procedures. An aliquot of the final control rinse water is passed over the
cleaned equipment directly into a sample container and submitted for analysis. The equipment
rinse blanks enable evaluation of bias (systematic errors) that could occur due to
decontamination.
A field duplicate is a replicate sample prepared at the sampling locations from equal portions of
all sample aliquots combined to make the sample. Both the field duplicate and the sample are
collected at the same time, in the same container type, preserved in the same way, and
analyzed by the same laboratory as a measure of sampling and analytical precision.
Field QA/QC samples will be analyzed for the same constituents as proposed for the soil and
groundwater samples as identified on Tables 5 and 6, respectively.
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7.4.7 Decontamination Procedures
DECONTAMINATION PAD
A decontamination pad will be constructed for field cleaning of drilling equipment. The
decontamination pad will meet the following requirements:
• The pad will be constructed in an area believed to be free of surface contamination
• The pad will be lined with a water-impermeable material with no seams within the pad.
The material should be easily replaced (disposable) or repairable.
• If possible, the pad will be constructed on a level, paved surface to facilitate the removal
of decontamination water. This may be accomplished by either constructing the pad with
one corner lower than the rest, or by creating a lined sump or pit in one corner.
• Sawhorses or racks constructed to hold field equipment while being cleaned will be high
enough above ground to prevent equipment from being contacted by splashback during
decontamination
Decontamination water will be allowed to percolate into the ground adjacent to the
decontamination pad. Containment and disposal of decontamination water is not required.
At the completion of field activities, the decontamination pad will be removed and any sump or
pit will be backfilled with appropriate material.
DECONTAMINATION OF FIELD SAMPLING EQUIPMENT
Field sampling equipment will be decontaminated between sample locations using potable
water and phosphate and borax-free detergent solution and a brush, if necessary, to remove
particulate matter and surface films. Equipment will then be rinsed thoroughly with tap water to
remove detergent solution prior to use at the next sample location.
DECONTAMINATION OF DRILLING EQUIPMENT
Any down-hole drilling equipment will be steam cleaned between boreholes. The following
procedure will be used for field cleaning augers, drill stems, rods, tools, and associated
down-hole equipment.
• Hollow-stem augers, bits, drilling rods, split-spoon samplers, and other down-hole
equipment will be placed on racks or sawhorses at least 2 feet above the floor of the
temporary decontamination pad. Soil, mud, and other material will be removed by hand,
brushes, and potable water. The equipment will be steam cleaned using a
high-pressure, high-temperature steam cleaner.
• Down-hole equipment will be rinsed thoroughly with potable water after steam cleaning
The clean equipment will then be removed from the decontamination pad and either placed on
the drill rig if mobilizing immediately to the next boring or placed on and covered with clean,
unused plastic sheeting if not used immediately.
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7.5 Site Hydrogeologic Conceptual Model
The data obtained during the proposed assessment will be supplemented by available reports
and data on site geotechnical, geologic, and hydrologic conditions to develop a site
hydrogeologic conceptual model (SCM). The scope of these efforts will depend upon site
conditions and existing geologic information for the site.
The SCM is a conceptual interpretation of the processes and characteristics of a site with
respect to the groundwater flow and other hydrologic processes at the site and will be a
refinement of the ICSM described in Section 5.0.
The NCDENR document “Hydrogeologic Investigation and Reporting Policy Memorandum”
dated May 31, 2007, will be used as general guidance. In general, components of the SCM will
consist of developing and describing the following aspects of the site: geologic/soil framework,
hydrologic framework, and the hydraulic properties of site materials. More specifically, the SCM
will describe how these aspects of the site affect the groundwater flow at the site. In addition to
these site aspects, the SCM will:
• Describe the site and regional geology
• Present longitudinal and transverse cross-sections showing the hydrostratigraphic layers
• Develop the hydrostratigraphic layer properties required for the groundwater model
• Present a groundwater contour map showing the potentiometric surface of the shallow
aquifer
• Present information on horizontal and vertical groundwater gradients
The SCM will serve as the basis for developing understanding the hydrogeologic characteristics
of the site and for developing a groundwater flow and transport model.
The historic site groundwater elevations and ash basin water elevations will be used to develop
a historic estimated seasonal high groundwater contour map for the site.
A fracture trace analysis will be performed for the site as well as on-site/near-site geologic
mapping to better understand site geology and to confirm and support the SCM.
7.6 Site-Specific Background Concentrations
Statistical analysis will be performed using methods outlined in the Resource Conservation and
Recovery Act (RCRA) Unified Guidance (USEPA, 2009, EPA 530/R-09-007) to develop SSBCs.
The SSBCs will be determined to assess whether or not exceedances can be attributed to
naturally occurring background concentrations or attributed to potential contamination.
Specifically, the relationship between exceedances and turbidity will be explored to determine
whether or not there is a possible correlation due to naturally occurring conditions and/or well
construction. Alternative background boring locations will be proposed to NCDENR if the
background wells shown on Figure 3 are found to not represent background conditions.
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7.7 Groundwater Fate and Transport Model
A three-dimensional groundwater fate and transport model will be developed for the ash basin
site. The objective of the model process will be to:
• Predict concentrations of the Constituents of Potential Concern (COPC) at the facility’s
compliance boundary or other locations of interest over time
• Estimate the groundwater flow and loading to surface water discharge areas
• Support the development of the CSA report and the corrective action plan, if required
The model and model report will be developed in general accordance with the guidelines found
in the memorandum Groundwater Modeling Policy, NCDENR DWQ, May 31, 2007 (DENR
modeling guidelines).
The groundwater model will be developed from the SCM, from existing wells and boring
information provided by Duke Energy, and from information developed from the site
investigation. The model will also be supplemented with additional information developed by
HDR from other Piedmont sites as applicable. The SCM is a conceptual interpretation of the
processes and characteristics of a site with respect to the groundwater flow and other
hydrologic processes at the site. Development of the SCM is discussed in Section 7.5.
Although the site is anticipated in general to conform to the LeGrand conceptual groundwater
model, due to the configuration of the ash basin, the additional possible sources (structural fill
and ash landfills), and the boundary conditions present at the site, HDR believes that a three-
dimensional groundwater model would be more appropriate than performing two-dimensional
modeling. The modeling process, the development of the model hydrostratigraphic layers, the
model extent (or domain), and the proposed model boundary conditions are presented below.
7.7.1 MODFLOW/MT3DMS Model
The groundwater modeling will be performed under the direction of Dr. William Langley, PE,
Department of Civil and Environmental Engineering, University of North Carolina Charlotte
(UNCC). Groundwater flow and constituent fate and transport will be modeled using Visual
MODFLOW 2011.1 (flow engine USGS MODFLOW 2005 from SWS) and MT3DMS.
Duke Energy, HDR, and UNCC considered the appropriateness of using MODFLOW and
MT3DMS as compared to the use of MODFLOW coupled with a geochemical reaction code
such as PHREEQC. The decision to use MODFLOW and MT3DMS was based on the intensive
data requirements of PHREEQC, the complexity of developing an appropriate geochemical
model given the heterogeneous nature of Piedmont geology, and the general acceptance of
MODLFOW and MT3DMS. However, batch PHREEQC simulations may be used to estimate
sensitivity of the proposed sorption constants used with MODFLOW/MT3DMS, as described
below, if geochemistry varies significantly across the site.
Additional factors that were considered in the decision to use MT3DMS as compared to a
reaction-based code utilizing geochemical modeling were as follows:
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1. Modeling the complete geochemical fate and transport of trace, minor, or major
constituents would require simultaneous modeling of the following in addition to
groundwater flow:
• All major, minor, and trace constituents (in their respective species forms) in
aqueous, equilibrium (solid), and complexed phases
• Solution pH, oxidation/reduction potential, alkalinity, dissolved oxygen, and
temperature
• Reactions including oxidation/reduction, complexation, precipitation/dissolution, and
ion exchange
2. Transient versus steady-state reaction kinetics may need to be considered. In general,
equilibrium phases for trace constituents cannot be identified by mineralogical analysis.
In this case, speciation geochemical modeling is required to identify postulated solid
phases by their respective saturation indices.
3. If geochemical conditions across the site are not widely variable, an approach that
considers each modeled COPC as a single species in the dissolved and complexed, or
sorbed, phases is justified. The ratio of these two phases is prescribed by the sorption
coefficient Kd which has dimensions of volume (L3) per unit mass (M). The variation in
geochemical conditions can be considered, if needed, by examining pH,
oxidation/reduction potential, alkalinity, and dissolved oxygen, perhaps combined with
geochemical modeling, to justify the Kd approach utilized by MT3DMS. Geochemical
modeling using PHREEQC (Parkhurst et al. 2013) running in the batch mode can be
used to indicate the extent to which a COPC is subject to solubility constraints, a
variable Kd, or other processes.
The groundwater model will be developed in general accordance with the guidelines found in
the Groundwater Modeling Policy, NCDENR DWQ, May 31, 2007, and based on discussions
previously conducted concerning groundwater modeling between Duke Energy, HDR, UNCC,
and NCDENR.
7.7.2 Development of Kd Terms
It is critical to determine the ability of the site soils to attenuate, adsorb, or through other
processes reduce the concentrations of COPCs that may impact groundwater. To determine the
capacity of the site soils to attenuate a COPC, the site-specific Kd terms will be developed by
UNCC utilizing soil samples collected during the site investigation. These Kd terms quantify the
equilibrium relationship between chemical constituents in the dissolved and sorbed phases.
For soils at the site, sorption is most likely the reversible, exchange-site type associated with
hydrous oxides of iron on weathered soil surfaces (NCDENR DWQ 2012). Experiments to
quantify sorption can be conducted using batch or column procedures (Daniels and Das 2014).
A batch sorption procedure generally consists of combining soil samples and solutions across a
range of soil-to-solution ratios, followed by shaking until chemical equilibrium is achieved. Initial
and final concentrations of chemicals in the solution determine the adsorbed amount of
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chemical and provide data for developing plots of sorbed versus dissolved chemical and the
resultant Kd term. If the plot, or isotherm, is linear, the single-valued Kd is considered linear as
well. Depending on the chemical constituent and soil characteristics, non-linear isotherms may
also result (EPRI 2004).
The column sorption procedure consists of passing a solution of known chemical concentration
through a cylindrical column packed with the soil sample. Batch and column methods for
estimating sorption were considered in development of the Kd terms. UNCC recommends an
adaption of the column method (Daniels and Das 2014) to develop Kd estimates that are more
conservative and representative of in-situ conditions, especially with regard to soil-to-liquid
ratios.
Soil samples with measured dry density and maximum particle size will be placed in lab-scale
columns configured to operate in the up-flow mode. A solution with measured COPC
concentrations will be pumped through each column as effluent samples are collected at regular
intervals over time. When constituent breakthroughs are verified, a “clean” solution (no COPCs)
will be pumped through the columns and effluent samples will be collected as well. Samples will
be analyzed by inductively coupled plasma-mass spectroscopy (ICP-MS) and ion
chromatography (IC) in the Civil & Environmental Engineering laboratories at the EPIC Building,
UNC Charlotte. COPCs measured in the column effluent as a function of cumulative pore
volumes displaced will be analyzed using CXTFIT (Tang et al. 2010) to select the
appropriate adsorption model and associated parameters of the partition coefficient Kd, either
linear, Freundlich, or Langmuir. This allows use of a nonlinear partition coefficient in the event
that the linear partition coefficient is not suitable for the modeled input concentration range.
It is noted that some COPCs may have indeterminate Kd values by the column method due to
solubility constraints and background conditions. In this case, batch sorption tests will be
conducted in accordance with U.S. Environmental Protection Agency (EPA) Technical Resource
Document EPA/530/SW-87/006-F, Batch-type Procedures for Estimating Soil Adsorption of
Chemicals. COPC-specific solutions will be used to prepare a range of soil-to-solution ratios.
After mixing, supernatant samples will be drawn and analyzed as described above. Plots of
sorbed versus dissolved COPC mass will be used to develop Kd terms. Batch tests will be
performed in triplicate.
When applied in the fate and transport modeling performed by MT3DMS, the Kds will determine
the extent to which COPC transport in groundwater flow is attenuated by sorption. In effect,
simulated COPC concentrations will be reduced, as will their rate of movement in advection in
groundwater.
Ten (10) soil core samples will be selected from representative material at the site for column
tests to be performed in triplicate. Additionally, batch Kd tests, if performed, will be executed in
triplicate.
These Kd terms will apply to the selected soil core samples and background geochemistry of
the test solution including pH and oxidation-reduction potential. In order to make these results
transferable to other soils and geochemical conditions at the site, UNCC recommends that the
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core samples with derived Kds and 20 to 25 additional core samples be analyzed for hydrous
ferrous oxides (HFO) content, which is considered to the primary determinant of COPC sorption
capacity of soils at the site. In the groundwater modeling study, the correlation between derived
Kds and HFO content can be used to estimate Kd at other site locations where HFO and
background water geochemistry, especially pH and oxidation-reduction potential, are known. If
significant differences in water geochemistry are observed, batch geochemical modeling can be
used to refine the Kd estimate as described in Section 7.1.1. UNCC recommends that core
samples for Kd and HFO tests be taken from locations that are in the path of groundwater
flowing from the ash impoundments.
Determination of which COPCs will have Kd terms developed will be determined after review of
the analyses on the site ash and review of the site groundwater analyses results. The COPCs
selected will be considered simultaneously in each test. Competitive sorption is taken into
account implicitly in the lab-measured sorption terms as COPCs are combined into a single test
solution. Significant competition sorption is not anticipated given that COPCs in groundwater,
where present, will be at trace levels.
7.7.3 MODFLOW/MT3DMS Modeling Process
The MODFLOW groundwater model will be developed using the hydrostratigraphic layer
geometry and properties of the site as described in this section. After the geometry and
properties of the model layers are input, the model will be calibrated to existing water levels
observed in the monitoring wells and ash basin. Infiltration into the areas outside of the ash
basin will be estimated based on available information. Infiltration within the basin will be
estimated based on available water balance information and pond elevation data provided by
Duke Energy.
The MT3MS portion of the model will utilize the Kd terms and the input concentrations of
constituents found in the ash. The leaching characteristics of ash are complex and expected to
vary with time and as changes occur in the geochemical environment of the ash basin. Due to
factors such as quantity of a particular constituent found in ash, mineral complex, solubility, and
geochemical conditions, the rate of leaching and leached concentrations of constituents will vary
with time and respect to each other. The experience that UNCC brings to this process through
their years of working with leaching and characterization of ash, particularly with Duke Energy
ash, will be of particular value.
Since the ash within the basin has been placed over a number of years, the analytical results
from an ash sample collected during the groundwater assessment is unlikely to represent the
current concentrations that are present in the hydrologic pathway between the ash basin and a
particular groundwater monitoring well or other downgradient location.
As a result of these factors and due to the time period involved in groundwater flow,
• Concentrations may vary spatially over time, and
• Peak concentrations may not yet have arrived at compliance wells.
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The selection of the initial concentrations and the predictions of the concentrations for
constituents with respect to time will be developed with consideration of the following:
• Site specific analytical results from leach tests (SPLP) and from total digestion of ash
samples taken at varying locations and depths within the ash basin. Note that the total
digestion concentrations, if used, would be considered an upper bound to concentrations
and that the actual concentrations would be lower that the results from the total
digestion.
• Analytical results from appropriate groundwater monitoring wells or surface water
sample locations outside of the ash basin
• Analytical results from monitoring wells installed in the ash basin pore water
(screened-in ash)
• Published or other data on sequential leaching tests performed on similar ash
The information above will be used with constituent concentrations measured at the compliance
boundary to calibrate the fate and transport model and to develop a representation of the
concentration with respect to time for a particular constituent. The starting time of the model will
correspond to the date that the ash basin was placed in service. The resulting model, which will
be consistent with the calibration targets mentioned above, can then be used to predict
concentrations over space and time.
The model calibration process will consist of varying hydraulic conductivity and retardation
within and between hydrostratigraphic units in a manner that is consistent with measured values
of hydraulic conductivity, sorption terms, groundwater levels, and COPC concentrations.
A sensitivity analysis will be performed for the fate and transport analyses.
The model report will contain the information required by Section II of the NCDENR modeling
guidelines, as applicable.
7.7.4 Hydrostratigraphic Layer Development
The three-dimensional configuration of the groundwater model hydrostratigraphic layers for a
site will be developed using the Initial Site Conceptual Model (Section 5.0) and from pre-existing
data and data obtained during the site investigation process. The thickness and extent for the
various layers will be represented by a three-dimensional surface model for each
hydrostratigraphic layer. For most sites the hydrostratigraphic layers will include ash, fills (both
for dikes/dam and/or ash landfills/structural fills), soil/saprolite, transition zone (where present),
and bedrock (Section 5.3).
The boring data from the site investigation and from existing boring data, as available and
provided by Duke Energy, will be entered into the RockWorks16TM program. This program,
along with site-specific and regional knowledge of Piedmont hydrogeology, will be used to
interpret and develop the layer thickness and extent across areas of the site where boring data
is not available. The material layers will be categorized based on physical and material
properties such as standard penetration blow count for soil/saprolite, and percent recovery and
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RQD for the transition zone and bedrock. The material properties required for the model such as
total porosity, effective porosity, and specific storage for ash, fill, alluvium, and soil/saprolite will
be developed from laboratory testing (grain size analysis as described in Section 7.1.1) and
published data. Hydraulic conductivity (horizontal and vertical) of all layers will be developed
utilizing existing site data, in-situ permeability testing (falling head, constant head, and packer
testing where appropriate), slug tests in completed monitoring wells, laboratory testing of
undisturbed samples (ash, fill, soil/saprolite), and from an extensive database of Piedmont soil
and rock properties developed by HDR (Sections 7.1.1 and 7.1.6). The effective porosity
(primarily fracture porosity) and specific storage of the transition zone and bedrock will be
estimated from published data.
7.7.5 Domain of Conceptual Groundwater Flow Model
The Allen ash basin model domain encompasses the area where groundwater flow will be
simulated to estimate the impacts of coal ash stored at the site. By necessity, the conceptual
model domain extends beyond the ash storage area proper to physical or artificial hydraulic
boundaries such that groundwater flow through the area is accurately simulated. Physical
hydraulic boundary types include specified head, head dependent flux, and no-flow types.
Artificial boundaries, which are developed based on information from the site investigation, may
include the specified head and no-flow types. In plan, the Allen model domain is bounded
approximately by the western bank of the Catawba River to the east, Plant Allen Road to the
north, South Point Road to the west, and Reese Wilson Road and Nutall Oak Lane to the south.
See Figures 2 and 3. The lower bound of the model domain coincides with the maximum depth
of water yielding fractures in bedrock. The basis for selecting these boundaries is described in
the following section. DENR will be notified if site conditions are encountered that warrant
changes to the proposed extent of the model.
7.7.6 Boundary Conditions for Conceptual Groundwater Flow Model
The western bank of the Catawba River is considered to be a specified head type where the
head is the average annual river stage for steady-state simulations, or the stage observed
simultaneously with groundwater level measurements at the site. The Catawba River is
considered to be the discharge boundary for all groundwater following through the model
domain. The proposed site investigation of river sediment properties and hydraulic head
differentials between near-shore piezometer/monitoring well water elevations and river stage
may indicate a head dependent flux type boundary is more appropriate.
Plant Allen Road to the north is considered to be an artificial, specified head boundary type.
Heads along this boundary will be interpolations of measured heads from adjacent piezometers
and monitoring wells. The proposed site investigation of hydraulic head differentials near this
boundary may indicate a no-flow type boundary is more appropriate.
South Point Road to the west is considered to be an artificial, specified head boundary type.
Heads along this boundary will be interpolations of measured heads from the nearest
piezometers and monitoring wells to the east of South Point Road.
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Reese Wilson Road and Nutall Oak Lane to the south are considered to be an artificial,
specified head boundary type. Heads along this boundary will be interpolations of measured
heads from adjacent piezometers and monitoring wells. The proposed site investigation of
hydraulic head differentials near this boundary may indicate a no-flow type boundary is more
appropriate.
Given that the hydrostratigraphic zones across the site are hydraulically connected these
boundaries are considered to be applicable to local (shallow) and regional (deep) groundwater
flow. If site conditions are encountered that warrant changes to the proposed extent of model,
DENR will be notified.
7.7.7 Groundwater Impacts to Surface Water
If the groundwater modeling predicts exceedances of the 2L Standards at or beyond the
compliance boundary where the plume containing the exceedances would intercept surface
waters, the groundwater model results will be coupled with modeling of surface waters to predict
contaminant concentrations in the surface waters. This work would be performed by HDR in
conjunction with UNCC.
Model output from the fate and transport modeling (i.e. groundwater volume flux and
concentrations of constituents with exceedances of the 2L Standards) will be used as input for
surface water modeling in the adjacent water bodies (i.e., streams or reservoirs). The level of
surface water modeling will be determined based on the potential for water quality impacts in
the adjacent water body. That is, if the available mixing and dilution of the groundwater plume
in the water body is sufficient that surface water quality standards are expected to be attained
within a short distance a simple modeling approach will be used. If potential water quality
impacts are expected to be such that the simple model approach is not sufficient, or if the water
body type requires a more complex analysis, then a more detailed modeling approach will be
used. A brief description of the simple and detailed modeling approaches is presented below.
• Simple Modeling Approach – This approach will include the effects of upstream flow on
dilution of the groundwater plume within allowable mixing zone limitations along with
analytical solutions to the lateral spreading and mixing of the groundwater plume in the
adjacent water body. This approach will be similar to that presented in EPA’s Technical
Support Document for Water Quality based Toxics Control (EPA/505/2-90-001) for
ambient induced mixing that considers lateral dispersion coefficient, upstream flow and
shear velocity. The results from this analysis will provide information constituent
concentration as a function of the spatial distance from the groundwater input to the
adjacent water body.
• Detailed Modeling Approach – This approach will involve the use of a water quality
model that is capable of representing a multi-dimensional analysis of groundwater plume
mixing and dilution in the adjacent water body. This method involves segmenting the
water body into model segments (lateral, longitudinal and/or vertical) for calculating the
resulting constituent concentrations spatially in the water body either in a steady-state or
time-variable mode. The potential water quality models that could be used for this
43
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7.0 Assessment Work Plan
approach include: QUAL2K; CE-QUAL-W2; EFDC/WASP; ECOMSED/RCA; or other
applicable models.
In either approach, the model output from the groundwater model will be coupled with the
surface water model to determine the resulting constituent concentrations in the adjacent water
body spatially from the point of input. These surface water modeling results can be used for
comparison to applicable surface water quality standards to complete determine compliance.
The development of the model inputs would require additional data for flow and chemical
characterization of the surface water that would potentially be impacted. The specific type of
data required (i.e., flow, chemical characterization, etc.) and the locations where this data would
be collected would depend on the surface water body and the modeling approach selected. If
modeling groundwater impacts to surface water is required, HDR and Duke Energy will consult
with the DWR regional office to present those specific data requirements and modeling
approach.
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8.0 Risk Assessment
8.0 Risk Assessment
To support the groundwater assessment and inform corrective action decisions, potential risks
to human health and the environment will be assessed in accordance with applicable federal
and state guidance. Initially, screening level human health and ecological risk assessments will
be conducted that include development of conceptual site models (CSM) to serve as the
foundation for evaluating potential risks to human and ecological receptors at the site.
Consistent with standard risk assessment practice, separate CSMs will be developed for the
human health and ecological risk evaluations.
The purpose of the CSM is to identify potentially complete exposure pathways to environmental
media associated with the site and to specify the types of exposure scenarios relevant to
include in the risk analysis. The first step in constructing a CSM is to characterize the site and
surrounding area. Source areas and potential transport mechanisms are then identified,
followed by determination of potential receptors and routes of exposure. Potential exposure
pathways are determined to be complete when they contain the following aspects: 1) a
constituent source, 2) a mechanism of constituent release and transport from the source area to
an environmental medium, and 3) a feasible route of potential exposure at the point of contact
(e.g., ingestion, dermal contact, and inhalation). Completed exposure pathways identified in the
CSM are then evaluated in the risk assessment. Incomplete pathways are characterized by
some gaps in the links between site sources and exposure. Based on this lack of potential
exposure, incomplete pathways are not included in the estimation or characterization of
potential risks since no exposure can occur via these pathways.
Preliminary COPCs for inclusion in the screening level risk assessments will be identified based
on the preliminary evaluations performed at the site in conjunction with recommendations from
NCDENR regarding coal ash constituents. Both screening level risk assessments will compare
maximum constituent concentrations to appropriate risk-based screening values as a
preliminary step in evaluating potential for risks to receptors. Based on results of the screening
level risk assessments, a refinement of COPCs will be conducted and more definitive risk
characterization will be performed as part of the corrective action process if needed.
8.1 Human Health Risk Assessment
As noted above, the initial human health risk assessment (HHRA) will include the preparation of
a CSM illustrating potential exposure pathways from the source area to possible receptors. The
information gathered in the CSM will be used in conjunction with analytical data collected as
part of the CSA. Although groundwater appears to be the primary exposure pathway for human
receptors, a screening level evaluation will be performed to determine if other potential
exposure routes exist.
The HHRA for the site will include an initial comparison of constituent concentrations in various
media to risk-based screening levels. The data will be screened against the following criteria:
45
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8.0 Risk Assessment
• Soil analytical results will be compared to USEPA residential and industrial soil Regional
Screening Levels (RSLs) (USEPA, November 2014 or latest update)
• Groundwater results will be compared to USEPA tap water RSLs (USEPA, October
2014) and NCDENR Title 15A, Subchapter 2L Standards (NCDENR 2006)
• Surface water analytical results will be compared to USEPA national recommended
water quality criteria and North Carolina surface water standards (USEPA 2006;
NCDENR 2007)
• The surface water classification as it pertains to drinking water supply, aquatic life,
high/exceptional quality designations and other requirements for other activities (e.g.,
landfill permits, NPDES wastewater discharges) shall be noted
• Sediment results will be compared to USEPA residential soil RSLs (USEPA, November
2014 or latest update)
• The soil, sediment, and groundwater data will also be compared to available background
soil, sediment, and groundwater data from previous monitoring and investigations
The results of this comparison will be presented in a table along with recommendations for
further evaluation.
8.1.1 Site-Specific Risk-Based Remediation Standards
If deemed necessary, based on the results of the initial comparison to standards, site- and
media-specific risk-based remediation standards will be calculated in accordance with the
Eligibility Requirements and Procedures for Risk-Based Remediation of Industrial Sites
Pursuant to N.C.G.S. 130A-310.65 to 310.77, North Carolina Department of Environment and
Natural Resources, Division of Waste Management, 29 July 2011.
These calculations will include an evaluation of the following based on site-specific activities and
conditions:
• Remediation methods and technologies resulting in emissions of air pollutants are to
comply with applicable air quality standards adopted by the Environmental Management
Commission (Commission)
• Site-specific remediation standards for surface waters are to be the water quality
standards adopted by the Commission
• The current and probable future use of groundwater shall be identified and protected.
Site-specific sources of contaminants and potential receptors are to be identified,
protected, controlled, or eliminated whether on or off the site of the contaminant source.
• Natural environmental conditions affecting the fate and transport of contaminants (e.g.,
natural attenuation) shall be determined by appropriate scientific methods
• Permits for facilities subject to the programs or requirements of G.S. 130A-310.67(a)
shall include conditions to avoid exceedances of applicable groundwater standards
pursuant to Article 21 of Chapter 143 of the General Statutes; permitted facilities shall be
designed to avoid exceedances of the North Carolina ground or surface water standards
46
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8.0 Risk Assessment
• Soil shall be remediated to levels that no longer constitute a continuing source of
groundwater contamination in excess of the site-specific groundwater remediation
standards approved for the site
• The potential for human inhalation of contaminants from the outdoor air and other site-
specific indoor air exposure pathways shall be considered during remediation, if
applicable
• The site-specific remediation standard shall protect against human exposure to
contamination through the consumption of contaminated fish or wildlife and through the
ingestion of contaminants in surface water or groundwater supplies
• For known or suspected carcinogens, site-specific remediation standards shall be
established at levels not to exceed an excess lifetime cancer risk of one in a million. The
site-specific remediation standard may depart from this level based on the criteria set out
in 40 Code of Federal Regulations § 300.430(e)(9) (July 1, 2003). The cumulative
excess lifetime cancer risk to an exposed individual shall not be greater than 1 in 10,000
based on the sum of carcinogenic risk posed by each contaminant present.
• For systemic toxicants (non-carcinogens), site-specific remediation standards shall be
set at levels to which the human population, including sensitive subgroups, may be
exposed without any adverse health effect during a lifetime or part of a lifetime. Site-
specific remediation standards for systemic toxicants shall incorporate an adequate
margin of safety and shall take into account cases where two or more systemic toxicants
affect the same organ or organ system.
• A comparison will also be made between the concentrations detected in ground water
and the constituent specific primary drinking water standards, as well as the
concentrations in impacted vs. background levels to determine if there are other
considerations that will need to be addressed in risk management decision making.
The site-specific remediation standards for each medium shall be adequate to avoid
foreseeable adverse effects to other media or the environment that are inconsistent with the
state’s risk-based approach.
8.2 Ecological Risk Assessment
The screening level ecological risk assessment (SLERA) for the site will begin with a description
of the ecological setting and development of the ecological CSM specific to the ecological
communities and receptors that may potentially be at risk. This scope is equivalent to Step 1:
preliminary problem formulation and ecological effects evaluation (USEPA 1998).
The screening level evaluation will include compilation of a list of potential ecological receptors
(e.g., plants, benthic invertebrates, fish, birds, etc.). Additionally, an evaluation of sensitive
ecological populations will be performed. Preliminary information on listed rare animal species
at or near the site will be compiled from the North Carolina Natural Heritage Program database
and U.S. Fish and Wildlife Service (USFWS) county list to evaluate the potential for presence of
rare or endangered animal and plant species. Rare natural communities will also be evaluated
and identified if near the site.
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8.0 Risk Assessment
Appropriate state and federal natural resource trustees and their representatives (e.g., USFWS)
will be contacted to determine the potential presence (or lack thereof) of sensitive species or
their critical habitat at the time the screening is performed. If it is determined a sensitive species
or critical habitat is present or potentially present, a survey of the appropriate area will be
conducted. If it is found that sensitive species are utilizing the site, or may in the future, a finding
concerning the likelihood of effects due to site-related contaminants or activities should be
developed and presented to the trustee agency.
The preliminary ecological risk screening will also include, as the basis for the CSM, a
description of the known fate and transport mechanisms for site-related constituents and
potentially complete pathways from assumed source to receptor. An ecological checklist will be
completed for the site as required by Guidelines for Performing Screening Level Ecological Risk
Assessment within North Carolina (NCDENR 2003).
Following completion of Step 1, the screening level exposure estimate and risk calculations
(Step 2) will be performed in accordance with the Guidelines for Performing Screening Level
Ecological Risk Assessment within North Carolina (NCDENR 2003). Step 2 estimates the level
of a constituent a plant or animal is exposed to at the site and compares the maximum
constituent concentrations to Ecological Screening Values (ESVs).
Maximum detected concentrations or the maximum detection limit for non-detected constituents
of potential concern (those metals or other chemicals present in site media that may result in
risk to ecological receptors) will be compared to applicable ESVs intended to be protective of
ecological receptors (including those sensitive species and communities noted above, where
available) to derive a hazard quotient (HQ). An HQ greater than 1 indicates potential ecological
impacts cannot be ruled out.
ESVs will be taken from the following and other appropriate sources:
• USEPA Ecological Soil Screening Levels
• USEPA Region 4 Recommended Ecological Screening Values
• USEPA National Recommended Water Quality Criteria and North Carolina Standards
The state’s SLERA guidance (NCDENR 2003) requires that constituents be identified as a
Step 2 COPC as follows:
• Category 1 – Contaminants with a maximum detection exceeding the ESV
• Category 2 – Undetected contaminants with a laboratory sample quantitation limit
exceeding the ESV
• Category 3 – Detected contaminants with no ESV
• Category 4 – Undetected contaminants with no ESV
Exceedances of the ESVs indicate the potential need for further evaluation of ecological risks at
the site. The frequency, magnitude, pattern, and basis of any exceedances should also be
considered.
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8.0 Risk Assessment
The process ultimately identifies a Scientific-Management Decision Point (SMDP) to determine
if ecological threats are absent and no further assessment is needed; if further assessment
should be performed to determine whether risks exist; or if there is the possibility of adverse
ecological effects and, therefore, a determination made on whether a more detailed ecological
risk and/or habitat assessment is needed and, if so, the scope of the assessment(s).
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9.0 CSA Report
9.0 CSA Report
The CSA report will be developed in the format required by the NORR which includes the
following components:
• Executive Summary
• Site History and Source Characterization
• Receptor Information
• Regional Geology and Hydrogeology
• Site Geology and Hydrogeology
• Soil Sampling Results
• Groundwater Sampling Results
• Hydrogeological Investigation
• Groundwater Modeling results
• Risk Assessment
• Discussion
• Conclusions and Recommendations
• Figures
• Tables
• Appendices
The CSA report will provide the results of one iterative assessment phase. No off-site
assessment or access agreements are anticipated to be utilized during this task other than for
the possible additional off-site wells discussed in Section 6.0.
The CSA will be prepared to include the items contained in the Guidelines for Comprehensive
Site Assessment (guidelines) included as an attachment to the NORR, as applicable. HDR will
provide the applicable figures, tables, and appendices as listed in the guidelines.
As part of CSA deliverables, a minimum the following tables, graphs, and maps will be provided:
• Box (whisker) plots for locations sampled on four or more events showing the quartiles
of the data along with minimum and maximum. Plots will be aligned with multiple
locations on one chart. Similar charts will be provided for each constituent of concern
(COC).
• Stacked time-series plots will be provided for each COC. Multiple wells/locations will be
stacked using the same x-axis to discern seasonal trends. Turbidity, dissolved oxygen,
ORP, or other constituents will be shown on the plots where appropriate to demonstrate
influence.
• Piper and/or stiff diagrams showing selected monitoring wells and surface water
locations as separate symbols
• Correlation charts where applicable
• Orthophoto potentiometric maps for shallow, deep, and bedrock wells
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Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
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9.0 CSA Report
• Orthophoto potentiometric difference maps showing the difference in vertical heads
between selected flow zones
• Orthophoto iso-concentration maps for selected COCs and flow zones
• Orthophoto map showing the relationship between groundwater and surface water
samples for selected COCs
• Geologic cross-sections
• Photographs of select split-spoon samples and cores at each boring location
• Others as appropriate
Recommendations will be provided in the CSA report for a sampling plan to be performed after
completion of this groundwater assessment. The sampling plan will describe the recommended
sampling frequency, constituent and parameter list, and proposed sampling locations including
monitoring wells, seeps, and surface water sample locations as required.
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10.0 Proposed Schedule
10.0 Proposed Schedule
Duke Energy will submit the CSA Report within 180 days of NCDENR approval of this Work
Plan. The anticipated schedule for implementation of field work, evaluation of data, and
preparation of the Work Plan is presented in the table below.
Activity Start Date Duration to Complete
Field Exploration Program 10 days following Work Plan approval 75 days
Receive Laboratory Data 14 days following end of Exploration Program 15 days
Evaluate Lab/Field Data, Develop SCM 5 days following receipt of Lab Data 30 days
Prepare and Submit CSA 10 days following Work Plan approval 170 days
In addition, the following permits and approvals from NCDENR will potentially be required to
commence field work:
• If site land disturbance, equal to or greater than 1 acre, is required for access and
clearing associated with drilling work, an erosion and sedimentation control permit must
be approved by the NCDENR Division of Energy, Mineral and Land Resources, Land
Quality Section.
• Installation of monitoring wells and/or soil borings on the dams and/or dikes at the ash
basin site must be approved by the NCDENR Division of Energy, Mineral and Land
Resources, Dam Safety Section prior to drilling. Location and well construction details
will be submitted following approval of the proposed locations.
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11.0 References
11.0 References
1. Daniel, C.C., III and Sharpless, N.B. 1983. Ground-water supply potential and
procedures for well-site selection upper Cape Fear basin, Cape Fear basin study, 1981-
1983: North Carolina Department of Natural Resources and Community Development
and U.S. Water Resources Council in cooperation with the U.S. Geological Survey, 73 p.
2. Daniels, John L. and Das, Gautam P. 2014. Practical Leachability and Sorption
Considerations for Ash Management, Geo-Congress 2014 Technical Papers: Geo-
characterization and Modeling for Sustainability. Wentworth Institute of technology,
Boston, MA.
3. Cunningham, W. L. and C. C. Daniels, III. 2001. Investigation of ground-water availability
and quality in Orange County, North Carolina: U. S. Geological Survey, Water-
Resources Investigations Report 00-4286, 59p.
4. Electric Power Research Institute (EPRI). 2014. Assessment of Radioactive Elements in
Coal Combustion Products, 2014 Technical Report 3002003774, Final Report. August
2014.
5. EPRI. 2009. Electric Power Research Institute, Technical Update – Coal Combustion
Products – Environmental Issues – Coal Ash: Characteristics, Management and
Environmental Issues, EPRI 1019022. September 2009.
6. EPRI. 2004. Electric Power Research Institute, Chemical Attenuation Coefficients for
Arsenic Species Using Soil Samples Collected from Selected Power Plant Sites:
Laboratory Studies, Product ID:1005505. December 2004.
7. EPRI. 1993. Electric Power Research Institute, Physical and Hydraulic Properties of Fly
Ash and Other By-Products from Coal Combustion, EPRI TR-101999. February 1993.
8. Fenneman, Nevin Melancthon. 1938. “Physiography of eastern United States.” McGraw-
Hill.
9. Freeze, R. A., J. A. and Cherry. 1979. Ground Water, Englewood Cliffs, NJ, Prentice-
Hall.
10. Gillispie, EC., Austin, R., Abraham, J., Wang, S., Bolich, R., Bradley, P., Amoozegar, A.,
Duckworth, O., Hesterberg, D., and Polizzotto, ML. 2014. Sources and variability of
manganese in well water of the North Carolina Piedmont. Water Resources Research
Institute of the University of North Carolina System Annual 2014 Conference, Raleigh,
NC, March 2014. Poster Presentation.
11. Harned, D. A. and Daniel, C. C., III. 1992. The transition zone between bedrock and
regolith: Conduit for contamination?, p. 336-348, in Daniel, C. C., III, White, R. K., and
Stone, P. A., eds., Groundwater in the Piedmont: Proceedings of a Conference on
53
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11.0 References
Ground Water in the Piedmont of the Eastern United States, October 16-18, 1989,
Clemson University, 693p.
12. HDR. 2014A. Allen Steam Station Ash Basin Drinking Water Supply Well and Receptor
Survey, NPDES Permit NC0004987.
13. HDR. 2014B. Allen Steam Station Ash Basin Supplement to Drinking Water Supply Well
and Receptor Survey.
14. Heath, R.C. 1980. Basic elements of groundwater hydrology with reference to conditions
in North Carolina: U.S. Geo-logical Survey Open-File Report 80–44, 86 p.
15. Heath, R.C. 1984, Ground-water regions of the United States. U.S. Geological Survey
Water-Supply Paper 2242, 78 p.
16. Krauskopf, K.B. 1972. Geochemistry of micronutrients: in Micronutrients in Agriculture,
J.J. Mortvedt, F.R. Cox, L.M. Shuman, and R.M. Walsh, eds., Soil Science Society of
America, Madison, Wisconsin, p. 7-36.
17. LeGrand, H.E. 1988. Region 21, Piedmont and Blue Ridge. In Hydrogeology, The
Geology of North America, vol. O-2, ed. W.B. Back, J.S. Rosenshein, and P.R. Seaber,
201–207. Geological Society of America. Boulder CO: Geological Society of America.
18. LeGrand, H.E. 1989. A conceptual model of ground water settings in the Piedmont
region. In Ground Water in the Piedmont , ed. C.C. Daniel III, R.K. White, and P.A.
Stone, 693. Proceedings of a Conference on Ground Water in the Piedmont of the
Eastern United States, Clemson University, Clemson, South Carolina. Charlotte, NC:
U.S. Geological Survey.
19. LeGrand, Harry E. 2004. A Master Conceptual Model for Hydrogeological Site
Characterization in the Piedmont and Mountain Region of North Carolina, A Guidance
Manual, North Carolina Department of Environment and Natural Resources Division of
Water Quality, Groundwater Section.
20. NCDENR. 2003. Division of Waste Management - Guidelines for Performing Screening
Level Ecological Risk Assessments within North Carolina.
21. NCDENR. 2007. Memorandum “Performance and Analysis of Aquifer Slug Tests and
Pumping Tests Policy,” May 31, 2007.
22. NCDENR. 2007. “Hydrogeologic Investigation and Reporting Policy Memorandum”
dated May 31, 2007.
23. NCDENR DWQ NCDENR Division of Water Quality. 2013. Evaluating Metals in
Groundwater at DWQ Permitted Facilities: A Technical Assistance Document for DWQ
Staff, July 2013.
24. Parkhurst, D.L., and Appelo, C.A.J., 2013, Description of input and examples for
PHREEQC version 3—A computer program for speciation, batch-reaction, one-
54
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11.0 References
dimensional transport, and inverse geochemical calculations: U.S. Geological Survey
Techniques and Methods, book 6, chap. A43, 497 p.
25. Tang, G., Mayes, M. A., Parker, J. C., & Jardine, P. M. (2010). CXTFIT/Excel–A modular
adaptable code for parameter estimation, sensitivity analysis and uncertainty analysis for
laboratory or field tracer experiments. Computers & Geosciences, 36(9), 1200-1209.
26. USEPA. 1987. Batch-type procedures for estimating soil adsorption of chemicals
Technical Resource Document 530/SW -87/006-F.
27. USEPA. 1997. Ecological Risk Assessment Guidance for Superfund: Process for
Designing and Conducting Ecological Risk Assessments.
28. USEPA. 2001. Region 4 Ecological Risk Assessment Bulletins—Supplement to RAGS.
29. USEPA. 1998. Guidelines for Ecological Risk Assessment.
30. US FWS. 2009. Range-wide Indiana Bat Protection and Enhancement Plan Guidelines,
at http://www.fws.gov/frankfort/pdf/inbatpepguidelines.pdf.
31. US Geological Survey (USGS). 1961. Akio Ogata and R.B. Banks Professional Paper
411-A “A Solution of Differential Equation of Longitudinal Dispersion in Porous Media.”
32. US Geological Survey (USGS). 1997. Radioactive elements in coal and fly ash:
abundance, forms, and environmental significance. U.S. Geological Survey Fact Sheet
FS-163-97.
33. USEPA. 1998. Study of Hazardous Air Pollutant Emissions from Electric Utility Steam
Generating Units—Final Report to Congress. Volume 1. Office of Air Quality, Planning
and Standards. Research Triangle Park, NC 27711, EPA-453/R-98-004a.
34. USEPA. 1998. Report to Congress Wastes from the Combustion of Fossil Fuels, Volume
2 Methods, Findings, and Recommendations.
55
Figures
Tables
Table 1. Groundwater Monitoring Requirements
Well Nomenclature Constituents and Parameters Frequency
Monitoring Wells: AB-1R, AB-4S,
AB-4D, AB-9S*, AB-9D*, AB-10S*,
AB-10D*, AB-11D, AB-12S, AB-12D,
AB-13S, AB-13D, AB-14D
Antimony Chromium Nickel Thallium
March, July,
November
Arsenic Copper Nitrate Water Level
Barium Iron pH Zinc
Boron Lead Selenium
Cadmium Manganese Sulfate
Chloride Mercury TDS
Note: Monitoring wells marked with * are located inside of the compliance boundary.
Table 2. Monitoring Well Locations
Monitoring Well Locations Monitoring Well
At or Near the Compliance
Boundary
AB-1R, AB-4S, AB-4D, AB-11D,
AB-12S, AB-12D, AB-13S,
AB-13D, AB-14D
Inside of the Compliance
Boundary
AB-9S, AB-9D, AB-10S, AB-10D
Tables - Page 1
Table 3. Exceedances of 2L Standards March 2011–November 2014
Parameter Boron Iron Manganese Nickel pH
Units µg/L µg/L µg/L µg/L SU
2L Standard 700 300 50 100 6.5 - 8.5
Well ID Range of Exceedances
AB -1R No
Exceedances 381 No
Exceedances
No
Exceedances 5.9 – 6.4
AB-4S No
Exceedances 314 – 555 64 – 285 No
Exceedances 5.8 – 6.1
AB -4D No
Exceedances
No
Exceedances
No
Exceedances
No
Exceedances 5.8 – 6.3
AB-9S 708 – 740 5,600 – 10,500 9,320 – 10,200 No
Exceedances 6.1 – 6.5
AB -9D No
Exceedances 356 – 909 95 No
Exceedances 6.4
AB -10S No
Exceedances 333 - 704 373 - 526 No
Exceedances 5.9 – 6.3
AB-10D No
Exceedances 307 – 881 53 – 144 No
Exceedances 5.9 – 6.4
AB-11D No
Exceedances 355 – 844 No
Exceedances
No
Exceedances 5.5 – 6.1
AB -12S No
Exceedances 573 53 – 56 No
Exceedances 4.7 – 5.2
AB-12D No
Exceedances 307 – 823 No
Exceedances
No
Exceedances 6.1 – 6.4
AB -13S No
Exceedances 324 – 817 55 – 165 No
Exceedances 5.3 – 5.9
AB-13D No
Exceedances 391 – 3,100 57 – 240 No
Exceedances 5.9 – 6.4
AB-14D No
Exceedances 301 – 8,350 52 – 945 104 – 544 5.2 – 6.2
Tables - Page 2
Table 4. Environmental Exploration and Sampling Plan
ALLEN STEAM STATION
Exploration
Area Soil Borings Shallow Monitoring Wells Deep Monitoring Wells Bedrock Monitoring Wells Water Supply Well Surface Water/Seep
Boring IDs Quantity
Estimated
Boring
Depth
(ft bgs)
Well IDs Quantity
Estimated
Well Depth
(ft bgs)
Screen
Length
(ft)
Well IDs Quantity
Estimated
Casing
Depth
(ft bgs)
Estimated
Well
Depth
(ft bgs)
Screen
Length
(ft)
Well IDs Quantity
Estimated
Casing
Depth
(ft bgs)
Estimated
Well
Depth
(ft bgs)
Screen
Length
(ft)
Well ID Quantity
Quantity
of
Locations
Quantity
of
Samples
Active Ash
Basin
AB-20
through
AB-28,
SB-7, SB-8,
SB-9
12 70-120
AB-20S
through
AB-28S,
AB-21SL,
AB-24SL,
and AB-25SL
12 15-50 10-15
AB-20D
through
AB-28D
9 55-105 70-120 5 N/A N/A N/A N/A N/A N/A N/A 4 10
Inactive
Ash Basin
AB-29
through
AB-39,
SB-1
through
SB-6
17 45-110
AB-29S
through
AB-39S,
AB-29SL
12 15-60 10-15
AB-29D
through
AB-39D
11 30-95 45-110 5 AB-35BR 1 50-120 120-170 5 N/A N/A N/A N/A
Beyond
Waste
Boundary
N/A 0 N/A
GWA-1S
through
GWA-9S
9 20-35 15
GWA-1D
through
GWA-9D
9 30-75 45-90 5
GWA-1BR,
GWA-3BR,
GWA-6BR
3 50-100 100-150 5
Existing
Water
Supply
Wells
2 9 Seeps 18
Background BG-1, BG-2,
and BG-3 3 60-120
BG-1S,
BG-2S, and
BG-3S
3 30-55 15
BG-1D,
BG-2D, and
BG-3D
3 45-105 60-120 5 BG-2BR 1 65-125 125-175 5 N/A N/A N/A N/A
Notes:
1. Estimated boring and well depths based on data available at the time of work plan preparation and subject to change based on site-specific conditions in the field.
2. Laboratory analyses of soil, ash, groundwater, and surface water samples will be performed in accordance with the constituents and methods identified in Tables 5 and 6.
3. Additionally, soils will be tested in the laboratory to determine grain size (with hydrometer), specific gravity, and permeability.
4. During drilling operations, downhole testing will be conducted to determine in-situ soil properties such as horizontal and vertical hydraulic conductivity.
5. Actual number of field and laboratory tests will be determined in field by Field Engineer or Geologist in accordance with project specifications.
6. Seep sample locations include both water and sediment samples.
Tables - Page 3
Table 5. Soil and Ash Parameters and Constituent Analytical Methods
INORGANIC COMPOUNDS UNITS METHOD
Antimony mg/kg EPA 6020A
Arsenic mg/kg EPA 6020A
Barium mg/kg EPA 6010C
Boron mg/kg EPA 6010C
Cadmium mg/kg EPA 6020A
Chloride mg/kg EPA 9056A
Chromium mg/kg EPA 6010C
Copper mg/kg EPA 6010C
Iron mg/kg EPA 6010C
Lead mg/kg EPA 6020A
Manganese mg/kg EPA 6010C
Mercury mg/kg EPA Method 7470A/7471B
Nickel mg/kg EPA 6010C
pH SU EPA 9045D
Selenium mg/kg EPA 6020A
Thallium (low level) (SPLP Extract only) mg/kg EPA 6020A
Zinc mg/kg EPA 6010C
Notes:
1. Soil samples to be analyzed for Total Inorganics using USEPA Methods 6010/6020 and pH
using USEPA Method 9045, as noted above.
2. Ash samples to be analyzed for Total Inorganics using USEPA Methods 6010/6020 and pH
using USEPA Method 9045; select ash samples will also be analyzed for leaching potential
using SPLP Extraction Method 1312 in conjunction with USEPA Methods 6010/6020. SPLP
results to be reported in units of mg/L for comparison to 2L Standards.
Tables - Page 4
Table 6. Groundwater, Surface Water, and Seep Parameters and Constituent Analytical Methods
PARAMETER RL UNITS METHOD
FIELD PARAMETERS
pH NA SU Field Water Quality Meter
Specific Conductance NA mmho/cm Field Water Quality Meter
Temperature NA ºC Field Water Quality Meter
Dissolved Oxygen NA mg/L Field Water Quality Meter
Oxidation Reduction Potential NA mV Field Water Quality Meter
Turbidity NA NTU Field Water Quality Meter
Ferrous Iron NA mg/L Field Test Kit
INORGANICS
Aluminum 5 µg/L EPA 200.7 or 6010C
Antimony 1 µg/L EPA 200.8 or 6020A
Arsenic 1 µg/L EPA 200.8 or 6020A
Barium 5 µg/L EPA 200.7 or 6010C
Beryllium 1 µg/L EPA 200.8 or 6020A
Boron 50 µg/L EPA 200.7 or 6010C
Cadmium 1 µg/L EPA 200.8 or 6020A
Chromium 1 µg/L EPA 200.7 or 6010C
Cobalt 1 µg/L EPA 200.8 or 6020A
Copper 0.005 mg/L EPA 200.7 or 6010C
Iron 10 µg/L EPA 200.7 or 6010C
Lead 1 µg/L EPA 200.8 or 6020A
Manganese 5 µg/L EPA 200.7 or 6010C
Mercury (low level) 0.012 µg/L EPA 245.7 or 1631
Molybdenum 5 µg/L EPA 200.7 or 6010C
Nickel 5 µg/L EPA 200.7 or 6010C
Total Combined Radium (Ra-226 and Ra-228) 4 5 pCi/L EPA 903.0
Selenium 1 µg/L EPA 200.8 or 6020A
Strontium 5 µg/L EPA 200.7 or 6010C
Thallium (low level) 0.2 µg/L EPA 200.8 or 6020A
Vanadium (low level) 0.3 mg/L EPA 200.8 or 6020A
Zinc 5 µg/L EPA 200.7 or 6010C
ANIONS/CATIONS
Alkalinity (as CaCO3) 20 mg/L SM 2320B
Bicarbonate 20 mg/L SM 2320
Calcium 0.01 mg/L EPA 200.7
Carbonate 20 mg/L SM 2320
Chloride 0.1 mg/L EPA 300.0 or 9056A
Magnesium 0.005 mg/L EPA 200.7
Nitrate as Nitrogen 0.023 mg-N/L EPA 300.0 or 9056A
Potassium 0.1 mg/L EPA 200.7
Sodium 0.05 mg/L EPA 200.7
Sulfate 0.1 mg/L EPA 300.0 or 9056A
Sulfide (as H 2 S) 5 0.05 mg/L SM4500S-D
Total Dissolved Solids 25 mg/L SM 2540C
Total Organic Carbon 0.1 mg/L SM 5310
Total Suspended Solids 2 mg/L SM 2450D
ADDITIONAL GROUNDWATER CONSTITUENTS
Iron Speciation (Fe(II),Fe(III) Vendor Specific µg/L IC-ICP-CRC-MS
Manganese Speciation (Mn(II), Mn(III), Mn(IV)) Vendor Specific µg/L IC-ICP-CRC-MS
Notes:
1. Select constituents will be analyzed for total and dissolved concentrations.
2. RL is the laboratory analytical method reporting limit.
3. NA indicates not applicable.
4. Voluntary monitoring well AB-8D and the proposed background wells BG-3S/D will be sampled for total combined radium.
5. Sulfide (as H 2 S) will be analyzed for groundwater samples only.
6. Select wells will be sampled for iron and manganese speciation as described in Section 7.2.3 of the work plan.
7. All EPA methods and RLs are at or below the respective 2L or 2B Standard for constituents with standards.
1
Tables - Page 5
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Depth to
Water Temp.DO Cond.pH ORP Turbidity Alkalinity Aluminum Beryllium
Feet ˚C mg/L µmhos/cm SU mV NTU mg/L CaCO3 mg/L µg/L
NA NA NA NA 6.5 - 8.5 NA NA NE NE 4*
Analytical Method 2320B4d
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date Total Total Dissolved Total Dissolved Total Dissolved Total Total Dissolved Total Dissolved Total
AB-1 Compliance Transition (Saprolite)11/2/2004 N/A 18 N/A 62 6.1 N/A 97 N/A N/A N/A N/A N/A <2 N/A 36 N/A N/A N/A N/A <0.5
AB-1 Compliance Transition (Saprolite)5/2/2005 N/A 15 N/A 61 6.3 N/A N/A N/A N/A N/A N/A N/A <2 N/A 48 N/A N/A N/A N/A <0.5
AB-1 Compliance Transition (Saprolite)11/16/2005 N/A 17.04 N/A 55.4 6.2 N/A 76.6 N/A N/A N/A N/A N/A <2 N/A 26 N/A N/A <100 N/A <0.5
AB-1 Compliance Transition (Saprolite)5/8/2006 N/A 15.26 N/A 51.1 6.15 N/A 88.2 N/A N/A N/A N/A N/A <2 N/A 66 N/A N/A <100 N/A <0.5
AB-1 Compliance Transition (Saprolite)11/13/2006 N/A 14.56 N/A 46.6 6.09 N/A 211 N/A N/A N/A N/A N/A <2 N/A 46 N/A N/A <100 N/A <0.5
AB-1 Compliance Transition (Saprolite)5/14/2007 N/A 16.36 N/A 46.5 6.11 N/A 95.1 N/A N/A N/A N/A N/A <2 N/A 22 N/A N/A <100 N/A <0.5
AB-1 Compliance Transition (Saprolite)11/7/2007 N/A 13.91 N/A 45.2 5.94 N/A 73.4 N/A N/A N/A N/A N/A <2 N/A 31 N/A N/A <100 N/A <0.5
AB-1 Compliance Transition (Saprolite)5/14/2008 N/A 14.9 N/A 52.6 5.98 N/A 19.7 N/A N/A N/A N/A N/A <2 N/A 33 N/A N/A <100 N/A <0.5
AB-1 Compliance Transition (Saprolite)5/4/2010 60.53 16.69 N/A 49.5 5.97 N/A 640 N/A N/A N/A N/A N/A <1 N/A 132 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 3/1/2011 8.31 15.46 N/A 147 6.22 N/A 55.7 N/A N/A N/A <1 N/A <1 N/A 37 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 7/7/2011 8.78 17.78 N/A 142 6.06 N/A 13.6 N/A N/A N/A <1 N/A <1 N/A 33 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 11/1/2011 10.18 16.07 N/A 149 6.23 N/A 7.4 N/A N/A N/A <1 N/A <1 N/A 32 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 3/5/2012 8.31 15.89 0.05 144 6.39 327 13.5 N/A N/A N/A <1 N/A <1 N/A 33 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 7/5/2012 8.89 17.01 0.1 144 6.79 275 9.5 N/A N/A N/A <1 N/A <1 N/A 34 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 11/5/2012 9.66 16.28 0.11 146 6.2 397 8.89 <5 N/A N/A <1 N/A <1 N/A 33 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 3/4/2013 8.4 16.65 0.19 144 6.05 277 9.4 N/A N/A N/A <1 N/A <1 N/A 33 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 7/1/2013 7.73 17.03 0.08 146 5.94 374 13.3 N/A N/A <1 <1 <1 <1 34 35 N/A <50 <50 <1 <1
AB-10D Compliance Bedrock 11/6/2013 8.48 16.51 0.07 145 6.16 296 10.1 N/A N/A N/A <1 N/A <1 N/A 36 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 3/5/2014 8.26 15.1 0.17 148 5.97 404 17.1 N/A N/A N/A <1 N/A <1 N/A 36 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 7/7/2014 8.6 17.48 0.15 153 6.07 354 11.8 N/A N/A N/A <1 N/A <1 N/A 39 N/A N/A <50 N/A <1
AB-10D Compliance Bedrock 11/4/2014 8.55 16.32 0.1 153 6.27 371 9.02 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-10S Compliance Residuum 3/1/2011 8.31 14.38 N/A 152 6.13 N/A 11 N/A N/A N/A <1 N/A <1 N/A 38 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 7/7/2011 8.79 17.32 N/A 149 5.96 N/A 1.46 N/A N/A N/A <1 N/A <1 N/A 37 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 11/1/2011 10.15 16.79 N/A 152 6.15 N/A 23.6 N/A N/A N/A <1 N/A <1 N/A 43 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 3/5/2012 8.29 15.08 0.25 152 6.31 359 3.53 N/A N/A N/A <1 N/A <1 N/A 43 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 7/5/2012 8.89 17.21 0.12 155 6.73 277 1.01 N/A N/A N/A <1 N/A <1 N/A 44 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 11/5/2012 9.65 17.42 0.17 156 6.12 399 2.24 <5 N/A N/A <1 N/A <1 N/A 47 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 3/4/2013 8.37 15.05 0.47 155 5.9 340 2.38 N/A N/A N/A <1 N/A <1 N/A 45 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 7/1/2013 7.71 17.35 0.21 162 5.89 333 2.34 N/A N/A <1 <1 <1 <1 50 49 N/A <50 <50 <1 <1
AB-10S Compliance Residuum 11/6/2013 8.47 17.17 0.22 162 6.13 313 17.4 N/A N/A N/A <1 N/A <1 N/A 53 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 3/5/2014 8.21 14.1 0.35 161 5.88 434 7.44 N/A N/A N/A <1 N/A <1 N/A 52 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 7/7/2014 8.61 17.49 0.25 171 6.02 336 5.72 N/A N/A N/A <1 N/A <1 N/A 53 N/A N/A <50 N/A <1
AB-10S Compliance Residuum 11/4/2014 8.56 17.09 0.18 167 6.2 374 11.4 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-11D Compliance Bedrock 3/1/2011 9.21 14.14 N/A 106.7 5.99 N/A 21.2 N/A N/A N/A <1 N/A <1 N/A 41 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 7/7/2011 9.44 17.01 N/A 104.9 5.98 N/A 17.4 N/A N/A N/A <1 N/A <1 N/A 40 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 11/1/2011 11.02 15.72 N/A 107.2 6 N/A 17.6 N/A N/A N/A <1 N/A <1 N/A 40 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 3/5/2012 8.46 14.42 1.14 107 5.99 361 3.21 N/A N/A N/A <1 N/A <1 N/A 40 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 7/5/2012 10.67 17.08 0.92 110 5.91 406 69.3 N/A N/A N/A <1 N/A <1 N/A 47 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 11/5/2012 12.1 16.58 1.56 109 6.14 345 609 <5 N/A N/A <1 N/A <1 N/A 44 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 3/5/2013 9.04 9.59 4.26 111 5.77 384 6.77 N/A N/A N/A <1 N/A <1 N/A 42 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 7/2/2013 8.22 17.55 2.42 113 5.5 413 2.46 N/A N/A <1 <1 <1 <1 42 42 N/A <50 <50 <1 <1
AB-11D Compliance Bedrock 11/6/2013 9.68 16.28 4.58 111 6.09 343 16.4 N/A N/A N/A <1 N/A <1 N/A 45 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 3/5/2014 7.35 12.43 2.74 113 5.78 357 1.99 N/A N/A N/A <1 N/A <1 N/A 44 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 7/7/2014 8 16.1 0.62 114 5.83 346 10.3 N/A N/A N/A <1 N/A <1 N/A 43 N/A N/A <50 N/A <1
AB-11D Compliance Bedrock 11/4/2014 9.05 15.93 1.06 115 5.93 388 11.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-12D Compliance Bedrock 3/1/2011 13.39 15.23 N/A 148.6 6.09 N/A 7.6 N/A N/A N/A <1 N/A <1 N/A 57 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 7/7/2011 13.44 16.31 N/A 139.3 6.27 N/A 6.91 N/A N/A N/A <1 N/A <1 N/A 48 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 11/1/2011 15.86 15.15 N/A 144.2 6.27 N/A 8.64 N/A N/A N/A <1 N/A <1 N/A 48 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 3/5/2012 12.5 15.52 4.65 142 6.46 364 4.89 N/A N/A N/A <1 N/A <1 N/A 46 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 7/5/2012 16.01 15.89 5.18 145 6.33 395 3.63 N/A N/A N/A <1 N/A <1 N/A 47 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 11/5/2012 16.65 15.69 4.47 149 6.59 363 1.75 <5 N/A N/A <1 N/A <1 N/A 47 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 3/5/2013 13.14 14.94 4.57 151 6.36 374 8.64 N/A N/A N/A <1 N/A <1 N/A 48 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 7/2/2013 11.97 16.21 4.77 149 6.24 405 9.89 N/A N/A <1 <1 <1 <1 46 52 N/A <50 <50 <1 <1
AB-12D Compliance Bedrock 11/6/2013 14.85 15.82 4.64 148 6.48 359 8.2 N/A N/A N/A <1 N/A <1 N/A 49 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 3/5/2014 10.99 15.06 4.76 154 6.24 351 5.33 N/A N/A N/A <1 N/A <1 N/A 47 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 7/7/2014 12.46 15.93 5.03 151 6.37 331 7.22 N/A N/A N/A <1 N/A <1 N/A 45 N/A N/A <50 N/A <1
AB-12D Compliance Bedrock 11/4/2014 14.65 15.71 4.71 156 6.38 370 2.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-12S Compliance Residuum 3/1/2011 14.01 14.43 N/A 23.7 5.16 N/A 2.63 N/A N/A N/A <1 N/A <1 N/A 31 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 7/7/2011 15.06 15.17 N/A 25 4.84 N/A 6.29 N/A N/A N/A <1 N/A <1 N/A 34 N/A N/A <50 N/A <1
200.7 200.8
15A NCAC 02L .0202(g) Groundwater Quality Standard 1*10 700 700 2
Boron
µg/L
Cadmium
µg/L
Field Measurements
Analytical Parameter Antimony Arsenic Barium
Units µg/L µg/L µg/L
200.8 200.8 200.7
Tables - Page 6
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Depth to
Water Temp.DO Cond.pH ORP Turbidity Alkalinity Aluminum Beryllium
Feet ˚C mg/L µmhos/cm SU mV NTU mg/L CaCO3 mg/L µg/L
NA NA NA NA 6.5 - 8.5 NA NA NE NE 4*
Analytical Method 2320B4d
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date Total Total Dissolved Total Dissolved Total Dissolved Total Total Dissolved Total Dissolved Total
200.7 200.8
15A NCAC 02L .0202(g) Groundwater Quality Standard 1*10 700 700 2
Boron
µg/L
Cadmium
µg/L
Field Measurements
Analytical Parameter Antimony Arsenic Barium
Units µg/L µg/L µg/L
200.8 200.8 200.7
AB-12S Compliance Residuum 11/1/2011 16.74 15.56 N/A 25.7 4.81 N/A 7.99 N/A N/A N/A <1 N/A <1 N/A 34 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 3/5/2012 13.08 14.63 1.81 25 5.06 433 5.8 N/A N/A N/A <1 N/A <1 N/A 37 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 7/5/2012 17.27 15.56 1.5 25 4.87 424 6.03 N/A N/A N/A <1 N/A <1 N/A 35 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 11/5/2012 16.98 15.65 1.15 25 5.19 417 3.56 <5 N/A N/A <1 N/A <1 N/A 37 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 3/5/2013 13.04 14.92 1.65 26 5.02 434 5.05 N/A N/A N/A <1 N/A <1 N/A 34 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 7/2/2013 12.96 14.88 2.64 26 4.75 457 5.08 N/A N/A <1 <1 <1 <1 34 38 N/A <50 <50 <1 <1
AB-12S Compliance Residuum 11/6/2013 15.55 16.06 0.97 26 5.1 445 9.9 N/A N/A N/A <1 N/A <1 N/A 38 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 3/5/2014 11.61 14.6 2.01 26 4.71 435 5.59 N/A N/A N/A <1 N/A <1 N/A 38 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 7/7/2014 14.32 15.56 2.23 26 4.94 390 15.8 N/A N/A N/A <1 N/A <1 N/A 40 N/A N/A <50 N/A <1
AB-12S Compliance Residuum 11/4/2014 15.7 15.5 0.79 26 5.01 422 5.55 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-13D Compliance Bedrock 3/1/2011 12.33 16.3 N/A 149 6.49 N/A 30.1 N/A N/A N/A <1 N/A <1 N/A 68 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 7/7/2011 11.42 17.74 N/A 158 6.2 N/A 11 N/A N/A N/A <1 N/A <1 N/A 51 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 11/1/2011 13.81 16.36 N/A 140 6.46 N/A 23.1 N/A N/A N/A <1 N/A <1 N/A 50 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 3/5/2012 10.35 16 3.09 140 6.67 355 50.1 N/A N/A N/A <1 N/A <1 N/A 75 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 7/5/2012 12.87 16.81 4.75 129 6.38 357 100 N/A N/A N/A <1 N/A <1 N/A 86 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 11/5/2012 14.42 16.11 N/A 126 6.53 N/A 169 <5 N/A N/A <1 N/A <1 N/A 116 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 3/4/2013 10.72 15.54 3.7 140 6.17 365 31.4 N/A N/A N/A <1 N/A <1 N/A 48 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 7/1/2013 8.91 19.15 1.97 154 5.98 485 9.82 N/A N/A <1 <1 <1 <1 41 49 N/A <50 <50 <1 <1
AB-13D Compliance Bedrock 11/7/2013 11.53 16.61 4.53 128 6.29 352 13.2 N/A N/A N/A <1 N/A <1 N/A 40 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 3/5/2014 7.98 14.3 2.41 152 5.93 348 3.75 N/A N/A N/A <1 N/A <1 N/A 47 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 7/7/2014 9.23 19.62 1.71 161 6.08 445 3.59 N/A N/A N/A <1 N/A <1 N/A 46 N/A N/A <50 N/A <1
AB-13D Compliance Bedrock 11/4/2014 11.75 17.22 2.16 154 6.31 438 1.91 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-13S Compliance Residuum 3/1/2011 12.47 16.03 N/A 112 5.92 N/A 20.3 N/A N/A N/A <1 N/A <1 N/A 26 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 7/7/2011 11.54 18.59 N/A 75 5.46 N/A 2.5 N/A N/A N/A <1 N/A <1 N/A 22 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 11/1/2011 14.19 16.95 N/A 69 5.48 N/A 7.46 N/A N/A N/A <1 N/A <1 N/A 24 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 3/5/2012 10.07 16.04 0.9 83 5.94 395 3.47 N/A N/A N/A <1 N/A <1 N/A 27 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 7/5/2012 13.34 19.86 1.26 72 5.32 392 2.65 N/A N/A N/A <1 N/A <1 N/A 30 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 11/5/2012 14.98 16.56 N/A 67 5.52 N/A 3.7 <5 N/A N/A <1 N/A <1 N/A 31 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 3/4/2013 10.56 15.45 2.13 127 5.74 390 11.4 N/A N/A N/A <1 N/A <1 N/A 39 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 7/1/2013 9 20.33 1.26 75 5.26 512 10 N/A N/A <1 <1 <1 <1 29 33 N/A <50 <50 <1 <1
AB-13S Compliance Residuum 11/7/2013 11.82 17.02 2.76 74 5.3 402 5.63 N/A N/A N/A <1 N/A <1 N/A 30 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 3/5/2014 7.83 14.32 2.1 94 5.5 356 12.7 N/A N/A N/A <1 N/A <1 N/A 38 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 7/7/2014 9.33 21.25 2.31 88 5.45 478 9.5 N/A N/A N/A <1 N/A <1 N/A 36 N/A N/A <50 N/A <1
AB-13S Compliance Residuum 11/4/2014 12.06 17.02 1.97 81 5.54 487 6.71 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-14D Compliance Bedrock 3/1/2011 15.26 16.2 N/A 174.2 6.17 N/A 12.7 N/A N/A N/A <1 N/A <1 N/A 117 N/A N/A <50 N/A <1
AB-14D Compliance Bedrock 7/21/2011 16.08 16.85 N/A 169.6 5.65 N/A 3.83 N/A N/A N/A <1 N/A <1 N/A 149 N/A N/A 59 N/A <1
AB-14D Compliance Bedrock 11/1/2011 17.4 16.42 N/A 166.2 5.58 N/A 10.4 N/A N/A N/A <1 N/A <1 N/A 136 N/A N/A 85 N/A <1
AB-14D Compliance Bedrock 3/5/2012 14.55 16.21 1.25 157 5.33 382 2.28 N/A N/A N/A <1 N/A <1 N/A 97 N/A N/A 116 N/A <1
AB-14D Compliance Bedrock 7/5/2012 18.63 16.8 2.08 138 5.54 374 5.45 N/A N/A N/A <1 N/A <1 N/A 84 N/A N/A 57 N/A <1
AB-14D Compliance Bedrock 11/5/2012 19.8 17.04 1.86 143 5.47 388 6.98 <5 N/A N/A <1 N/A <1 N/A 80 N/A N/A 84 N/A <1
AB-14D Compliance Bedrock 3/5/2013 15.29 16.26 1.59 156 5.24 392 6.48 N/A N/A N/A <1 N/A <1 N/A 82 N/A N/A 111 N/A <1
AB-14D Compliance Bedrock 7/2/2013 15.31 16.25 2.22 147 5.18 402 1.36 N/A N/A <1 <1 <1 <1 78 81 N/A 91 99 <1 <1
AB-14D Compliance Bedrock 11/7/2013 17.57 16.34 2.39 131 5.33 399 11.8 N/A N/A N/A <1 N/A <1 N/A 76 N/A N/A 65 N/A <1
AB-14D Compliance Bedrock 3/5/2014 14.15 16.12 2.29 153 5.16 391 2.28 N/A N/A N/A <1 N/A <1 N/A 80 N/A N/A 109 N/A <1
AB-14D Compliance Bedrock 7/7/2014 15.79 16.07 2.54 146 5.27 375 5.16 N/A N/A N/A <1 N/A <1 N/A 73 N/A N/A 82 N/A <1
AB-14D Compliance Bedrock 11/4/2014 16.95 16.24 3 139 5.35 408 5.76 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-1R Compliance Transition (Saprolite)3/1/2011 55.69 15.29 N/A 200.3 7.44 N/A 3.73 N/A N/A N/A <1 N/A <1 N/A 57 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)7/7/2011 55.26 17.37 N/A 155.3 6.54 N/A 6.35 N/A N/A N/A <1 N/A <1 N/A 51 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)11/1/2011 56.54 16.14 N/A 138 6.5 N/A 9.18 N/A N/A N/A <1 N/A <1 N/A 49 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)3/5/2012 56.33 15.84 7.23 129 6.47 323 2.36 N/A N/A N/A <1 N/A <1 N/A 42 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)7/5/2012 56.53 17.45 7.7 122 6.94 305 2.98 N/A N/A N/A <1 N/A <1 N/A 41 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)11/5/2012 57.87 16.06 7.3 112 6.12 424 3.45 <5 N/A N/A <1 N/A <1 N/A 41 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)3/4/2013 58.07 15.11 7.36 108 6.16 371 3.27 N/A N/A N/A <1 N/A <1 N/A 37 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)7/1/2013 56.72 17.09 7.63 109 5.92 458 1.03 N/A N/A <1 <1 <1 <1 38 38 N/A <50 <50 <1 <1
AB-1R Compliance Transition (Saprolite)11/7/2013 56.58 16.28 7.79 114 6.19 365 3.2 N/A N/A N/A <1 N/A <1 N/A 39 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)3/5/2014 55.61 15.64 7.85 127 6.17 403 2.56 N/A N/A N/A <1 N/A <1 N/A 41 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)7/7/2014 53.78 16.71 7.98 230 6.23 470 3.59 N/A N/A N/A <1 N/A <1 N/A 73 N/A N/A <50 N/A <1
AB-1R Compliance Transition (Saprolite)11/4/2014 54.24 16.17 8.19 304 6.38 448 2.87 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-2 Voluntary Transition (Saprolite)11/2/2004 N/A 16 N/A 32 5 N/A 44 N/A N/A N/A N/A N/A <2 N/A 35 N/A N/A N/A N/A 0.55
Tables - Page 7
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Depth to
Water Temp.DO Cond.pH ORP Turbidity Alkalinity Aluminum Beryllium
Feet ˚C mg/L µmhos/cm SU mV NTU mg/L CaCO3 mg/L µg/L
NA NA NA NA 6.5 - 8.5 NA NA NE NE 4*
Analytical Method 2320B4d
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date Total Total Dissolved Total Dissolved Total Dissolved Total Total Dissolved Total Dissolved Total
200.7 200.8
15A NCAC 02L .0202(g) Groundwater Quality Standard 1*10 700 700 2
Boron
µg/L
Cadmium
µg/L
Field Measurements
Analytical Parameter Antimony Arsenic Barium
Units µg/L µg/L µg/L
200.8 200.8 200.7
AB-2 Voluntary Transition (Saprolite)5/2/2005 N/A 14 N/A 26 5.1 N/A N/A N/A N/A N/A N/A N/A <2 N/A 41 N/A N/A N/A N/A <0.5
AB-2 Voluntary Transition (Saprolite)11/16/2005 N/A 16.33 N/A 32.2 5.2 N/A 28.4 N/A N/A N/A N/A N/A <2 N/A 35 N/A N/A <100 N/A <0.5
AB-2 Voluntary Transition (Saprolite)5/8/2006 N/A 13.98 N/A 25.9 5.04 N/A 24.7 N/A N/A N/A N/A N/A <2 N/A 37 N/A N/A <100 N/A <0.5
AB-2 Voluntary Transition (Saprolite)11/13/2006 N/A 15.12 N/A 28.1 5.07 N/A 12.7 N/A N/A N/A N/A N/A <2 N/A 35 N/A N/A <100 N/A <0.5
AB-2 Voluntary Transition (Saprolite)5/14/2007 N/A 14.16 N/A 26.5 5.02 N/A 5.45 N/A N/A N/A N/A N/A <2 N/A 30 N/A N/A <100 N/A <0.5
AB-2 Voluntary Transition (Saprolite)11/7/2007 N/A 13.78 N/A 25 5 N/A 7.94 N/A N/A N/A N/A N/A <2 N/A 32 N/A N/A <100 N/A <0.5
AB-2 Voluntary Transition (Saprolite)5/14/2008 N/A 14.3 N/A 28.3 5.07 N/A 11.7 N/A N/A N/A N/A N/A <2 N/A 38 N/A N/A <100 N/A <0.5
AB-2 Voluntary Transition (Saprolite)11/3/2008 N/A 15.34 N/A 41.5 5.23 N/A 28.8 N/A N/A N/A N/A N/A <2 N/A 19 N/A N/A <100 N/A <0.5
AB-2 Voluntary Transition (Saprolite)5/13/2009 N/A 13.84 N/A 31.7 4.79 N/A 19.8 N/A N/A N/A N/A N/A <1 N/A 13 N/A N/A <100 N/A <0.5
AB-2 Voluntary Transition (Saprolite)11/3/2009 N/A 15.08 N/A 29.7 5.11 N/A 5.88 N/A N/A N/A N/A N/A <1 N/A 18 N/A N/A <50 N/A <1
AB-2 Voluntary Transition (Saprolite)5/4/2010 12.95 14.16 N/A 30.2 5.04 N/A 7.89 N/A N/A N/A N/A N/A <1 N/A 17.2 N/A N/A <50 N/A <1
AB-2 Voluntary Transition (Saprolite)3/1/2011 14.86 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-2D Voluntary Partially Weathered Rock 11/2/2004 N/A 16 N/A 79 6.1 N/A 7.2 N/A N/A N/A N/A N/A <2 N/A 34 N/A N/A N/A N/A <0.5
AB-2D Voluntary Partially Weathered Rock 5/2/2005 N/A 15 N/A 75 6.2 N/A N/A N/A N/A N/A N/A N/A <2 N/A 34 N/A N/A N/A N/A <0.5
AB-2D Voluntary Partially Weathered Rock 11/16/2005 N/A 15.94 N/A 92.5 6.41 N/A 15.8 N/A N/A N/A N/A N/A <2 N/A 29 N/A N/A <100 N/A <0.5
AB-2D Voluntary Partially Weathered Rock 5/8/2006 N/A 15.14 N/A 79.1 6.22 N/A 17.3 N/A N/A N/A N/A N/A <2 N/A 34 N/A N/A <100 N/A <0.5
AB-2D Voluntary Partially Weathered Rock 11/13/2006 N/A 15.23 N/A 91 6.4 N/A 5.81 N/A N/A N/A N/A N/A <2 N/A 32 N/A N/A <100 N/A <0.5
AB-2D Voluntary Partially Weathered Rock 5/14/2007 N/A 15.51 N/A 78.3 6.26 N/A 0.63 N/A N/A N/A N/A N/A <2 N/A 26 N/A N/A <100 N/A <0.5
AB-2D Voluntary Partially Weathered Rock 11/7/2007 N/A 14.62 N/A 89.1 6.33 N/A 1.01 N/A N/A N/A N/A N/A <2 N/A 28 N/A N/A <100 N/A <0.5
AB-2D Voluntary Partially Weathered Rock 5/14/2008 N/A 15.63 N/A 81.3 6.22 N/A 4.63 N/A N/A N/A N/A N/A <2 N/A 29 N/A N/A <100 N/A <0.5
AB-2D Voluntary Partially Weathered Rock 11/3/2008 N/A 15.17 N/A 101.3 6.41 N/A 1.07 N/A N/A N/A N/A N/A <2 N/A 30 N/A N/A <100 N/A <0.5
AB-2D Voluntary Partially Weathered Rock 5/13/2009 N/A 15.38 N/A 75.1 5.98 N/A 2.01 N/A N/A N/A N/A N/A <1 N/A 31 N/A N/A <100 N/A <0.5
AB-2D Voluntary Partially Weathered Rock 11/3/2009 N/A 15.13 N/A 89.2 6.45 N/A 2.5 N/A N/A N/A N/A N/A <1 N/A 29.6 N/A N/A <50 N/A <1
AB-2D Voluntary Partially Weathered Rock 5/4/2010 13.47 15.94 N/A 75.2 6.2 N/A 1.46 N/A N/A N/A N/A N/A <2 N/A 29.6 N/A N/A <50 N/A <1
AB-2D Voluntary Partially Weathered Rock 3/1/2011 14.83 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-4D Compliance Partially Weathered Rock 11/2/2004 N/A 17 N/A 107 6.1 N/A 14 N/A N/A N/A N/A N/A <2 N/A 33 N/A N/A N/A N/A <0.5
AB-4D Compliance Partially Weathered Rock 5/2/2005 N/A 16 N/A 110 6.1 N/A N/A N/A N/A N/A N/A N/A <2 N/A 27 N/A N/A N/A N/A <0.5
AB-4D Compliance Partially Weathered Rock 11/16/2005 N/A 16.64 N/A 107.4 6.21 N/A 14.8 N/A N/A N/A N/A N/A <2 N/A 23 N/A N/A <100 N/A <0.5
AB-4D Compliance Partially Weathered Rock 5/8/2006 N/A 15.71 N/A 108.3 6 N/A 18.8 N/A N/A N/A N/A N/A <2 N/A 27 N/A N/A <100 N/A <0.5
AB-4D Compliance Partially Weathered Rock 11/13/2006 N/A 16.8 N/A 113.1 6.14 N/A 9.64 N/A N/A N/A N/A N/A <2 N/A 28 N/A N/A <100 N/A <0.5
AB-4D Compliance Partially Weathered Rock 5/14/2007 N/A 17.24 N/A 110.3 6.03 N/A 0.55 N/A N/A N/A N/A N/A <2 N/A 22 N/A N/A <100 N/A <0.5
AB-4D Compliance Partially Weathered Rock 11/7/2007 N/A 16.7 N/A 104 6 N/A 0.67 N/A N/A N/A N/A N/A <2 N/A 23 N/A N/A <100 N/A <0.5
AB-4D Compliance Partially Weathered Rock 5/14/2008 N/A 16.52 N/A 110.9 6.11 N/A 4.39 N/A N/A N/A N/A N/A <2 N/A 24 N/A N/A <100 N/A <0.5
AB-4D Compliance Partially Weathered Rock 11/3/2008 N/A 16.16 N/A 118.1 6.11 N/A 1.36 N/A N/A N/A N/A N/A <2 N/A 25 N/A N/A <100 N/A <0.5
AB-4D Compliance Partially Weathered Rock 5/13/2009 N/A 16.24 N/A 107 5.98 N/A 1.94 N/A N/A N/A N/A N/A <1 N/A 26 N/A N/A <100 N/A <0.5
AB-4D Compliance Partially Weathered Rock 11/3/2009 N/A 16.16 N/A 111.4 6.19 N/A 3.32 N/A N/A N/A N/A N/A <1 N/A 23.6 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 5/4/2010 7.33 16.94 N/A 116.5 6.1 N/A 2.09 N/A N/A N/A N/A N/A <1 N/A 25.5 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 3/1/2011 12.02 16.78 N/A 109.9 6.3 N/A 0.27 N/A N/A N/A <1 N/A <1 N/A 26 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 7/7/2011 11.53 17.82 N/A 109.7 5.96 N/A 6.12 N/A N/A N/A <1 N/A <1 N/A 25 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 11/1/2011 14.3 16.56 N/A 111.8 5.92 N/A 4.1 N/A N/A N/A <1 N/A <1 N/A 25 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 3/5/2012 10.76 16.02 4.25 111 5.98 354 1.02 N/A N/A N/A <1 N/A <1 N/A 25 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 7/5/2012 13.83 16.59 4.59 114 5.83 342 0.35 N/A N/A N/A <1 N/A <1 N/A 26 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 11/5/2012 15.34 16.41 N/A 117 6.07 N/A 0.52 <5 N/A N/A <1 N/A <1 N/A 27 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 3/5/2013 11.67 15.99 3.75 125 5.88 394 1.4 N/A N/A N/A <1 N/A <1 N/A 29 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 7/2/2013 9.93 16.34 4.22 118 5.81 391 0.52 N/A N/A <1 <1 <1 <1 28 27 N/A <50 <50 <1 <1
AB-4D Compliance Partially Weathered Rock 11/6/2013 12.64 16.49 4 120 5.9 358 2.24 N/A N/A N/A <1 N/A <1 N/A 30 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 3/5/2014 8.58 16.04 4.15 120 5.76 359 2.26 N/A N/A N/A <1 N/A <1 N/A 27 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 7/7/2014 9.63 16.69 3.75 130 5.85 340 5.56 N/A N/A N/A <1 N/A <1 N/A 30 N/A N/A <50 N/A <1
AB-4D Compliance Partially Weathered Rock 11/4/2014 12.23 16.22 3.96 127 5.93 389 1.97 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-4S (4)Compliance Transition (Saprolite)11/2/2004 N/A 17 N/A 82 5.3 N/A 147 N/A N/A N/A N/A N/A <2 N/A 55 N/A N/A N/A N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)5/2/2005 N/A 15 N/A 128 5.4 N/A N/A N/A N/A N/A N/A N/A <2 N/A 100 N/A N/A N/A N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)11/16/2005 N/A 17.56 N/A 97.8 5.45 N/A 39.9 N/A N/A N/A N/A N/A <2 N/A 46 N/A N/A <100 N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)5/8/2006 N/A 14.8 N/A 127.4 5.55 N/A 72.2 N/A N/A N/A N/A N/A <2 N/A 58 N/A N/A <100 N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)11/13/2006 N/A 17.93 N/A 165 6.13 N/A 58.2 N/A N/A N/A N/A N/A <2 N/A 69 N/A N/A <100 N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)5/14/2007 N/A 15.89 N/A 164.4 5.88 N/A 19.1 N/A N/A N/A N/A N/A <2 N/A 51 N/A N/A <100 N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)11/7/2007 N/A 17.35 N/A 168.9 5.58 N/A 40.6 N/A N/A N/A N/A N/A <2 N/A 59 N/A N/A <100 N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)5/14/2008 N/A 15.54 N/A 151 6.13 N/A 60.6 N/A N/A N/A N/A N/A <2 N/A 55 N/A N/A <100 N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)11/3/2008 N/A 17.12 N/A 169.7 5.92 N/A 24.4 N/A N/A N/A N/A N/A <2 N/A 51 N/A N/A <100 N/A <0.5
AB-4S (4)Compliance Transition (Saprolite)5/13/2009 N/A 15.1 N/A 145.6 6.01 N/A 12.7 N/A N/A N/A N/A N/A <1 N/A 39 N/A N/A <100 N/A <0.5
Tables - Page 8
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Depth to
Water Temp.DO Cond.pH ORP Turbidity Alkalinity Aluminum Beryllium
Feet ˚C mg/L µmhos/cm SU mV NTU mg/L CaCO3 mg/L µg/L
NA NA NA NA 6.5 - 8.5 NA NA NE NE 4*
Analytical Method 2320B4d
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date Total Total Dissolved Total Dissolved Total Dissolved Total Total Dissolved Total Dissolved Total
200.7 200.8
15A NCAC 02L .0202(g) Groundwater Quality Standard 1*10 700 700 2
Boron
µg/L
Cadmium
µg/L
Field Measurements
Analytical Parameter Antimony Arsenic Barium
Units µg/L µg/L µg/L
200.8 200.8 200.7
AB-4S (4)Compliance Transition (Saprolite)11/3/2009 N/A 17.14 N/A 148.3 6.05 N/A 15.3 N/A N/A N/A N/A N/A <1 N/A 37.3 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)5/4/2010 8.79 15.51 N/A 139.9 6.14 N/A 7.71 N/A N/A N/A N/A N/A <2 N/A 31.1 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)3/1/2011 13.07 15.89 N/A 125.5 6.14 N/A 9.46 N/A N/A N/A <1 N/A <1 N/A 33 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)7/7/2011 12.91 17.41 N/A 119.7 5.87 N/A 16.9 N/A N/A N/A <1 N/A <1 N/A 33 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)11/1/2011 15.61 17.11 N/A 142.8 5.82 N/A 11.2 N/A N/A N/A <1 N/A <1 N/A 37 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)3/5/2012 11.91 14.91 5.22 155 6.12 332 9.6 N/A N/A N/A <1 N/A <1 N/A 34 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)7/5/2012 15.22 16.39 0.46 117 5.87 330 5.92 N/A N/A N/A <1 N/A <1 N/A 31 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)11/5/2012 16.6 17.67 N/A 125 6.06 N/A 4.71 <5 N/A N/A <1 N/A <1 N/A 35 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)3/5/2013 12.71 14.16 5.72 138 6.07 392 15.7 N/A N/A N/A <1 N/A <1 N/A 32 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)7/2/2013 11.27 16.58 0.13 157 5.97 329 7.57 N/A N/A <1 <1 <1 <1 38 40 N/A <50 <50 <1 <1
AB-4S (4)Compliance Transition (Saprolite)11/6/2013 13.94 18.23 0.24 155 6.06 343 9.7 N/A N/A N/A <1 N/A <1 N/A 40 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)3/5/2014 9.77 15.24 0.59 141 5.95 321 7.09 N/A N/A N/A <1 N/A <1 N/A 30 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)7/7/2014 11.13 16.14 0.13 139 6.05 305 9.94 N/A N/A N/A <1 N/A <1 N/A 29 N/A N/A <50 N/A <1
AB-4S (4)Compliance Transition (Saprolite)11/4/2014 13.65 16.88 1.73 152 6.1 346 7.83 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-5 Voluntary Transition (Saprolite)11/2/2004 N/A 18 N/A 33 5.54 N/A 69 N/A N/A N/A N/A N/A <2 N/A 42 N/A N/A N/A N/A <0.5
AB-5 Voluntary Transition (Saprolite)5/2/2005 N/A 17 N/A 35 5.5 N/A N/A N/A N/A N/A N/A N/A <2 N/A 36 N/A N/A N/A N/A <0.5
AB-5 Voluntary Transition (Saprolite)11/16/2005 N/A 17.75 N/A 35.3 5.57 N/A 28.1 N/A N/A N/A N/A N/A <2 N/A 31 N/A N/A <100 N/A <0.5
AB-5 Voluntary Transition (Saprolite)5/8/2006 N/A 16.23 N/A 32.7 5.39 N/A 36 N/A N/A N/A N/A N/A <2 N/A 34 N/A N/A <100 N/A <0.5
AB-5 Voluntary Transition (Saprolite)11/13/2006 N/A 16.75 N/A 33.2 5.47 N/A 284 N/A N/A N/A N/A N/A <2 N/A 37 N/A N/A <100 N/A <0.5
AB-5 Voluntary Transition (Saprolite)5/14/2007 N/A 18.82 N/A 33.6 5.59 N/A 16 N/A N/A N/A N/A N/A <2 N/A 33 N/A N/A <100 N/A <0.5
AB-5 Voluntary Transition (Saprolite)11/7/2007 N/A 14.46 N/A 36.1 5.64 N/A 68.7 N/A N/A N/A N/A N/A <2 N/A 91 N/A N/A <100 N/A <0.5
AB-5 Voluntary Transition (Saprolite)5/14/2008 N/A 17.29 N/A 81.1 6.22 N/A 0 N/A N/A N/A N/A N/A <2 N/A 41 N/A N/A <100 N/A <0.5
AB-5 Voluntary Transition (Saprolite)11/3/2008 N/A 16.34 N/A 41.6 5.48 N/A 483 N/A N/A N/A N/A N/A <2 N/A 43 N/A N/A <100 N/A <0.5
AB-5 Voluntary Transition (Saprolite)5/13/2009 N/A 16.86 N/A 33.3 5.39 N/A 136 N/A N/A N/A N/A N/A <1 N/A 36 N/A N/A <100 N/A <0.5
AB-5 Voluntary Transition (Saprolite)11/3/2009 N/A 16.31 N/A 33.5 5.58 N/A 92.6 N/A N/A N/A N/A N/A <1 N/A 33.2 N/A N/A <50 N/A <1
AB-5 Voluntary Transition (Saprolite)5/4/2010 38.06 17.54 N/A 31 5.56 N/A 21.4 N/A N/A N/A N/A N/A <2 N/A 40.9 N/A N/A <50 N/A <1
AB-5 Voluntary Transition (Saprolite)3/1/2011 39.96 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-5 Voluntary Transition (Saprolite)7/7/2011 40.31 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-5 Voluntary Transition (Saprolite)11/1/2011 41.09 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-6A Voluntary Alluvium 3/21/2005 N/A 15 N/A 119 6.2 N/A 15.3 N/A N/A N/A N/A N/A <2 N/A 32 N/A N/A N/A N/A <0.5
AB-6A Voluntary Alluvium 5/2/2005 N/A 16 N/A 112 6.1 N/A N/A N/A N/A N/A N/A N/A <2 N/A 30 N/A N/A N/A N/A <0.5
AB-6A Voluntary Alluvium 11/16/2005 N/A 17.16 N/A 116.9 6.05 N/A 5.08 N/A N/A N/A N/A N/A <2 N/A 26 N/A N/A <100 N/A <0.5
AB-6A Voluntary Alluvium 5/8/2006 N/A 15.12 N/A 119.6 5.86 N/A 4.27 N/A N/A N/A N/A N/A <2 N/A 27 N/A N/A <100 N/A <0.5
AB-6A Voluntary Alluvium 11/13/2006 N/A 15.25 N/A 121 6.66 N/A 11.9 N/A N/A N/A N/A N/A <2 N/A 28 N/A N/A <100 N/A <0.5
AB-6A Voluntary Alluvium 5/14/2007 N/A 16.58 N/A 116 6.13 N/A 1.23 N/A N/A N/A N/A N/A <2 N/A 24 N/A N/A <100 N/A <0.5
AB-6A Voluntary Alluvium 11/7/2007 N/A 15.6 N/A 118.7 6 N/A 1.96 N/A N/A N/A N/A N/A <2 N/A 28 N/A N/A <100 N/A <0.5
AB-6A Voluntary Alluvium 5/14/2008 N/A 16.23 N/A 125 6.1 N/A 8.7 N/A N/A N/A N/A N/A <2 N/A 29 N/A N/A <100 N/A <0.5
AB-6A Voluntary Alluvium 11/3/2008 N/A 16.11 N/A 127.5 5.83 N/A 1.76 N/A N/A N/A N/A N/A <2 N/A 30 N/A N/A <100 N/A <0.5
AB-6A Voluntary Alluvium 5/13/2009 N/A 16.27 N/A 115 6.12 N/A 1.29 N/A N/A N/A N/A N/A <1 N/A 31 N/A N/A <100 N/A <0.5
AB-6A Voluntary Alluvium 11/3/2009 N/A 16.41 N/A 129 6.03 N/A 2.81 N/A N/A N/A N/A N/A <1 N/A 30.9 N/A N/A <50 N/A <1
AB-6A Voluntary Alluvium 5/4/2010 7.95 16.76 N/A 119 6.03 N/A 1.74 N/A N/A N/A N/A N/A <1 N/A 30.4 N/A N/A <50 N/A <1
AB-6A Voluntary Alluvium 3/1/2011 8.29 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-6A Voluntary Alluvium 7/7/2011 8.42 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-6A Voluntary Alluvium 11/1/2011 9.33 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-6R Voluntary Transition (Saprolite)3/21/2005 N/A 16 N/A 152 6.3 N/A 46.4 N/A N/A N/A N/A N/A <2 N/A 42 N/A N/A N/A N/A <0.5
AB-6R Voluntary Transition (Saprolite)5/2/2005 N/A 17 N/A 116 6.3 N/A N/A N/A N/A N/A N/A N/A <2 N/A 27 N/A N/A N/A N/A <0.5
AB-6R Voluntary Transition (Saprolite)11/16/2005 N/A 17.98 N/A 113.5 6.24 N/A 20.8 N/A N/A N/A N/A N/A <2 N/A 35 N/A N/A <100 N/A <0.5
AB-6R Voluntary Transition (Saprolite)5/8/2006 N/A 15.5 N/A 124 6 N/A 24.8 N/A N/A N/A N/A N/A <2 N/A 31 N/A N/A <100 N/A <0.5
AB-6R Voluntary Transition (Saprolite)11/13/2006 N/A 15.71 N/A 124 6.49 N/A 19.8 N/A N/A N/A N/A N/A <2 N/A 33 N/A N/A <100 N/A <0.5
AB-6R Voluntary Transition (Saprolite)5/14/2007 N/A 16.47 N/A 119 6.19 N/A 7.3 N/A N/A N/A N/A N/A <2 N/A 23 N/A N/A <100 N/A <0.5
AB-6R Voluntary Transition (Saprolite)11/7/2007 N/A 15.63 N/A 121 6.11 N/A 282 N/A N/A N/A N/A N/A <2 N/A 35 N/A N/A <100 N/A <0.5
AB-6R Voluntary Transition (Saprolite)5/14/2008 N/A 16.04 N/A 127 6.21 N/A 25.8 N/A N/A N/A N/A N/A <2 N/A 30 N/A N/A <100 N/A <0.5
AB-6R Voluntary Transition (Saprolite)11/3/2008 N/A 16.25 N/A 133.4 6 N/A 12.5 N/A N/A N/A N/A N/A <2 N/A 29 N/A N/A <100 N/A <0.5
AB-6R Voluntary Transition (Saprolite)5/13/2009 N/A 16.17 N/A 112 6.21 N/A 10 N/A N/A N/A N/A N/A <1 N/A 29 N/A N/A <100 N/A <0.5
AB-6R Voluntary Transition (Saprolite)11/3/2009 N/A 16.43 N/A 125 6.13 N/A 19.2 N/A N/A N/A N/A N/A <1 N/A 28.3 N/A N/A <50 N/A <1
AB-6R Voluntary Transition (Saprolite)5/4/2010 7.76 16.87 N/A 118 6.19 N/A 20.7 N/A N/A N/A N/A N/A <1 N/A 28.8 N/A N/A <50 N/A <1
AB-6R Voluntary Transition (Saprolite)3/1/2011 7.97 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-6R Voluntary Transition (Saprolite)7/7/2011 8.25 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-6R Voluntary Transition (Saprolite)11/1/2011 9.16 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tables - Page 9
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Depth to
Water Temp.DO Cond.pH ORP Turbidity Alkalinity Aluminum Beryllium
Feet ˚C mg/L µmhos/cm SU mV NTU mg/L CaCO3 mg/L µg/L
NA NA NA NA 6.5 - 8.5 NA NA NE NE 4*
Analytical Method 2320B4d
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date Total Total Dissolved Total Dissolved Total Dissolved Total Total Dissolved Total Dissolved Total
200.7 200.8
15A NCAC 02L .0202(g) Groundwater Quality Standard 1*10 700 700 2
Boron
µg/L
Cadmium
µg/L
Field Measurements
Analytical Parameter Antimony Arsenic Barium
Units µg/L µg/L µg/L
200.8 200.8 200.7
AB-8 Voluntary Transition (Saprolite)3/21/2005 N/A 18 N/A 202 6.4 N/A 17.7 N/A N/A N/A N/A N/A <2 N/A 126 N/A N/A N/A N/A <0.5
AB-8 Voluntary Transition (Saprolite)5/2/2005 N/A 18 N/A 196 6.3 N/A N/A N/A N/A N/A N/A N/A <2 N/A 120 N/A N/A N/A N/A <0.5
AB-8 Voluntary Transition (Saprolite)11/16/2005 N/A 18.42 N/A 197.2 6.32 N/A 12.3 N/A N/A N/A N/A N/A <2 N/A 97 N/A N/A 450 N/A <0.5
AB-8 Voluntary Transition (Saprolite)5/8/2006 N/A 17.39 N/A 194.9 5.98 N/A 4.16 N/A N/A N/A N/A N/A <2 N/A 104 N/A N/A 446 N/A <0.5
AB-8 Voluntary Transition (Saprolite)11/13/2006 N/A 17.6 N/A 192 6.46 N/A 1.5 N/A N/A N/A N/A N/A <2 N/A 104 N/A N/A 470 N/A <0.5
AB-8 Voluntary Transition (Saprolite)5/14/2007 N/A 18.15 N/A 187.3 6.25 N/A 1.02 N/A N/A N/A N/A N/A <2 N/A 96 N/A N/A 461 N/A <0.5
AB-8 Voluntary Transition (Saprolite)11/7/2007 N/A 17.28 N/A 189.2 6.19 N/A 1.92 N/A N/A N/A N/A N/A <2 N/A 98 N/A N/A 463 N/A <0.5
AB-8 Voluntary Transition (Saprolite)5/14/2008 N/A 18.26 N/A 198 6.23 N/A 2.8 N/A N/A N/A N/A N/A <2 N/A 98 N/A N/A 456 N/A <0.5
AB-8 Voluntary Transition (Saprolite)11/3/2008 N/A 18.11 N/A 201.6 5.92 N/A 0.57 N/A N/A N/A N/A N/A <2 N/A 101 N/A N/A 463 N/A <0.5
AB-8 Voluntary Transition (Saprolite)5/13/2009 N/A 17.87 N/A 184 6.1 N/A 0.35 N/A N/A N/A N/A N/A <1 N/A 103 N/A N/A 466 N/A <0.5
AB-8 Voluntary Transition (Saprolite)11/3/2009 N/A 17.4 N/A 203 6.17 N/A 0.56 N/A N/A N/A N/A N/A <1 N/A 105 N/A N/A 470 N/A <1
AB-8 Voluntary Transition (Saprolite)5/4/2010 13.51 18.44 N/A 191 6.08 N/A 0.81 N/A N/A N/A N/A N/A <1 N/A 98.4 N/A N/A 496 N/A <1
AB-9D Compliance Bedrock 3/1/2011 13.89 17.32 N/A 232 6.79 N/A 20.1 N/A N/A N/A <1 N/A <1 N/A 30 N/A N/A 578 N/A <1
AB-9D Compliance Bedrock 7/7/2011 14.32 19.13 N/A 223 6.61 N/A 8.66 N/A N/A N/A <1 N/A <1 N/A 26 N/A N/A 579 N/A <1
AB-9D Compliance Bedrock 11/1/2011 15.66 16.99 N/A 234 6.72 N/A 2.58 N/A N/A N/A <1 N/A <1 N/A 25 N/A N/A 590 N/A <1
AB-9D Compliance Bedrock 3/5/2012 13.81 17.76 0.18 228 6.89 255 4.37 N/A N/A N/A <1 N/A <1 N/A 25 N/A N/A 595 N/A <1
AB-9D Compliance Bedrock 7/5/2012 14.4 18.98 0.14 230 7.3 220 5.66 N/A N/A N/A <1 N/A <1 N/A 26 N/A N/A 569 N/A <1
AB-9D Compliance Bedrock 11/5/2012 15.16 18.43 0.14 232 6.53 344 2.68 <5 N/A N/A <1 N/A <1 N/A 26 N/A N/A 592 N/A <1
AB-9D Compliance Bedrock 3/4/2013 13.87 17.82 0.51 236 6.64 266 5.65 N/A N/A N/A <1 N/A <1 N/A 26 N/A N/A 561 N/A <1
AB-9D Compliance Bedrock 7/1/2013 13.38 19.38 0.44 240 6.4 364 5.5 N/A N/A <1 <1 <1 <1 26 28 N/A 575 577 <1 <1
AB-9D Compliance Bedrock 11/6/2013 14.04 19.16 2.26 241 6.78 262 13.2 N/A N/A N/A <1 N/A <1 N/A 29 N/A N/A 592 N/A <1
AB-9D Compliance Bedrock 3/5/2014 13.73 17.72 1.38 244 6.53 359 3.7 N/A N/A N/A <1 N/A <1 N/A 28 N/A N/A 576 N/A <1
AB-9D Compliance Bedrock 7/7/2014 14.11 18.94 0.42 254 6.53 337 5.37 N/A N/A N/A <1 N/A <1 N/A 28 N/A N/A 569 N/A <1
AB-9D Compliance Bedrock 11/4/2014 14.13 18.1 0.18 247 6.72 314 3.2 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AB-9S Compliance Transition (Saprolite)3/1/2011 12.1 18.18 N/A 218 6.21 N/A 10.1 N/A N/A N/A <1 N/A <1 N/A 137 N/A N/A 709 N/A <1
AB-9S Compliance Transition (Saprolite)7/7/2011 12.05 21.83 N/A 218 6.24 N/A 7.78 N/A N/A N/A <1 N/A <1 N/A 150 N/A N/A 698 N/A <1
AB-9S Compliance Transition (Saprolite)11/1/2011 12.87 20.74 N/A 241 6.48 N/A 9.99 N/A N/A N/A <1 N/A <1 N/A 147 N/A N/A 712 N/A <1
AB-9S Compliance Transition (Saprolite)3/5/2012 11.99 18.21 0.18 216 6.45 204 19.1 N/A N/A N/A <1 N/A <1 N/A 157 N/A N/A 735 N/A <1
AB-9S Compliance Transition (Saprolite)7/5/2012 12.19 21.65 0.18 230 6.98 152 18.9 N/A N/A N/A <1 N/A <1 N/A 164 N/A N/A 697 N/A <1
AB-9S Compliance Transition (Saprolite)11/5/2012 13.01 20.15 0.25 223 6.43 193 8.02 <5 N/A N/A <1 N/A <1 N/A 166 N/A N/A 721 N/A <1
AB-9S Compliance Transition (Saprolite)3/4/2013 11.84 17.97 0.26 221 6.28 191 9.72 N/A N/A N/A <1 N/A <1 N/A 157 N/A N/A 708 N/A <1
AB-9S Compliance Transition (Saprolite)7/1/2013 11.87 20.08 0.2 231 6.2 193 7.05 N/A N/A <1 <1 <1 <1 165 168 N/A 723 725 <1 <1
AB-9S Compliance Transition (Saprolite)11/6/2013 12.42 20.93 0.16 221 6.32 198 8.84 N/A N/A N/A <1 N/A <1 N/A 149 N/A N/A 729 N/A <1
AB-9S Compliance Transition (Saprolite)3/5/2014 11.76 17.7 0.2 214 6.11 225 8.5 N/A N/A N/A <1 N/A <1 N/A 170 N/A N/A 740 N/A <1
AB-9S Compliance Transition (Saprolite)7/7/2014 12.2 20.34 4.25 235 6.29 218 23.5 N/A N/A N/A <1 N/A <1 N/A 156 N/A N/A 686 N/A <1
AB-9S Compliance Transition (Saprolite)11/4/2014 12.71 18.9 0.21 229 6.49 182 4.87 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tables - Page 10
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
AB-1 Compliance Transition (Saprolite)11/2/2004
AB-1 Compliance Transition (Saprolite)5/2/2005
AB-1 Compliance Transition (Saprolite)11/16/2005
AB-1 Compliance Transition (Saprolite)5/8/2006
AB-1 Compliance Transition (Saprolite)11/13/2006
AB-1 Compliance Transition (Saprolite)5/14/2007
AB-1 Compliance Transition (Saprolite)11/7/2007
AB-1 Compliance Transition (Saprolite)5/14/2008
AB-1 Compliance Transition (Saprolite)5/4/2010
AB-10D Compliance Bedrock 3/1/2011
AB-10D Compliance Bedrock 7/7/2011
AB-10D Compliance Bedrock 11/1/2011
AB-10D Compliance Bedrock 3/5/2012
AB-10D Compliance Bedrock 7/5/2012
AB-10D Compliance Bedrock 11/5/2012
AB-10D Compliance Bedrock 3/4/2013
AB-10D Compliance Bedrock 7/1/2013
AB-10D Compliance Bedrock 11/6/2013
AB-10D Compliance Bedrock 3/5/2014
AB-10D Compliance Bedrock 7/7/2014
AB-10D Compliance Bedrock 11/4/2014
AB-10S Compliance Residuum 3/1/2011
AB-10S Compliance Residuum 7/7/2011
AB-10S Compliance Residuum 11/1/2011
AB-10S Compliance Residuum 3/5/2012
AB-10S Compliance Residuum 7/5/2012
AB-10S Compliance Residuum 11/5/2012
AB-10S Compliance Residuum 3/4/2013
AB-10S Compliance Residuum 7/1/2013
AB-10S Compliance Residuum 11/6/2013
AB-10S Compliance Residuum 3/5/2014
AB-10S Compliance Residuum 7/7/2014
AB-10S Compliance Residuum 11/4/2014
AB-11D Compliance Bedrock 3/1/2011
AB-11D Compliance Bedrock 7/7/2011
AB-11D Compliance Bedrock 11/1/2011
AB-11D Compliance Bedrock 3/5/2012
AB-11D Compliance Bedrock 7/5/2012
AB-11D Compliance Bedrock 11/5/2012
AB-11D Compliance Bedrock 3/5/2013
AB-11D Compliance Bedrock 7/2/2013
AB-11D Compliance Bedrock 11/6/2013
AB-11D Compliance Bedrock 3/5/2014
AB-11D Compliance Bedrock 7/7/2014
AB-11D Compliance Bedrock 11/4/2014
AB-12D Compliance Bedrock 3/1/2011
AB-12D Compliance Bedrock 7/7/2011
AB-12D Compliance Bedrock 11/1/2011
AB-12D Compliance Bedrock 3/5/2012
AB-12D Compliance Bedrock 7/5/2012
AB-12D Compliance Bedrock 11/5/2012
AB-12D Compliance Bedrock 3/5/2013
AB-12D Compliance Bedrock 7/2/2013
AB-12D Compliance Bedrock 11/6/2013
AB-12D Compliance Bedrock 3/5/2014
AB-12D Compliance Bedrock 7/7/2014
AB-12D Compliance Bedrock 11/4/2014
AB-12S Compliance Residuum 3/1/2011
AB-12S Compliance Residuum 7/7/2011
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
Chloride
mg/L
250
300
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total
N/A 4.157 3.8 N/A 1.2 N/A N/A N/A <0.002 N/A 1000 N/A <2 N/A 2.44 N/A 120 N/A <0.1 N/A N/A
N/A N/A 2.9 N/A 1.6 N/A N/A N/A <0.002 N/A 3100 N/A <2 N/A N/A N/A 170 N/A <0.1 N/A N/A
N/A 5.323 1.67 N/A 1.3 N/A N/A N/A <0.002 N/A 1048 N/A <2 N/A 2.04 N/A 41 N/A <0.1 N/A N/A
N/A 5.539 1.55 N/A 2.18 N/A N/A N/A <0.002 N/A 4491 N/A <2 N/A 3.623 N/A 146 N/A <0.1 N/A N/A
N/A 4.815 1.5 N/A 2.04 N/A N/A N/A 0.002 N/A 1620 N/A <2 N/A 2.594 N/A 86 N/A <0.2 N/A N/A
N/A 4.601 1.33 N/A 1.59 N/A N/A N/A <0.002 N/A 434 N/A <2 N/A 1.786 N/A 19 N/A <0.1 N/A N/A
N/A 4.495 1.47 N/A 2.12 N/A N/A N/A <0.002 N/A 1560 N/A <2 N/A 2.124 N/A 46 N/A <0.1 N/A N/A
N/A 4.64 1.5 N/A 3.74 N/A N/A N/A <0.002 N/A 1970 N/A <2 N/A 2.21 N/A 47 N/A <0.05 N/A N/A
N/A 6.17 1.5 N/A 4 N/A N/A N/A 0.005 N/A 9880 N/A 1.3 N/A 6.91 N/A 325 N/A <0.05 N/A N/A
N/A N/A 8.1 N/A 8 N/A N/A N/A <0.005 N/A 623 N/A <1 N/A N/A N/A 144 N/A <0.05 N/A N/A
N/A N/A 8.4 N/A <5 N/A N/A N/A <0.005 N/A 272 N/A <1 N/A N/A N/A 79 N/A <0.05 N/A N/A
N/A N/A 8.2 N/A <5 N/A N/A N/A <0.005 N/A 182 N/A <1 N/A N/A N/A 66 N/A <0.05 N/A N/A
N/A N/A 8.1 N/A 5 N/A N/A N/A <0.005 N/A 226 N/A <1 N/A N/A N/A 50 N/A <0.05 N/A N/A
N/A N/A 7.6 N/A 5 N/A N/A N/A <0.005 N/A 202 N/A <1 N/A N/A N/A 53 N/A <0.05 N/A N/A
N/A 14.1 8 N/A <5 N/A N/A N/A <0.005 N/A 180 N/A <1 N/A 3.46 N/A 69 N/A <0.05 N/A N/A
N/A 13.3 7.7 N/A 6 N/A N/A N/A <0.005 N/A 307 N/A <1 N/A 3.16 N/A 16 N/A <0.05 N/A N/A
14.4 14.4 7.5 <5 7 N/A N/A <0.005 <0.005 62 860 <1 <1 3.48 3.46 21 21 <0.05 <0.05 N/A N/A
N/A 14.7 8.1 N/A 6 N/A N/A N/A <0.005 N/A 473 N/A <1 N/A 3.38 N/A 12 N/A <0.05 N/A N/A
N/A 14.8 7.9 N/A 7 N/A N/A N/A <0.005 N/A 881 N/A <1 N/A 3.52 N/A 22 N/A <0.05 N/A N/A
N/A 14.7 7.6 N/A 6 N/A N/A N/A <0.005 N/A 623 N/A <1 N/A 3.45 N/A 11 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 9 N/A <5 N/A N/A N/A <0.005 N/A 394 N/A <1 N/A N/A N/A 396 N/A <0.05 N/A N/A
N/A N/A 8.7 N/A <5 N/A N/A N/A <0.005 N/A 71 N/A <1 N/A N/A N/A 401 N/A <0.05 N/A N/A
N/A N/A 9 N/A <5 N/A N/A N/A <0.005 N/A 393 N/A <1 N/A N/A N/A 419 N/A <0.05 N/A N/A
N/A N/A 8.7 N/A <5 N/A N/A N/A <0.005 N/A 60 N/A <1 N/A N/A N/A 373 N/A <0.05 N/A N/A
N/A N/A 8.6 N/A <5 N/A N/A N/A <0.005 N/A 43 N/A <1 N/A N/A N/A 409 N/A <0.05 N/A N/A
N/A 11.6 8.7 N/A <5 N/A N/A N/A <0.005 N/A 242 N/A <1 N/A 5.46 N/A 440 N/A <0.05 N/A N/A
N/A 11 8.1 N/A <5 N/A N/A N/A <0.005 N/A 61 N/A <1 N/A 5.15 N/A 390 N/A <0.05 N/A N/A
12.6 12.2 8.8 <5 <5 N/A N/A <0.005 <0.005 24 209 <1 <1 5.74 5.57 470 445 <0.05 <0.05 N/A N/A
N/A 12.7 9.2 N/A <5 N/A N/A N/A <0.005 N/A 704 N/A <1 N/A 5.87 N/A 526 N/A <0.05 N/A N/A
N/A 12.7 9.1 N/A <5 N/A N/A N/A <0.005 N/A 333 N/A <1 N/A 5.81 N/A 475 N/A <0.05 N/A N/A
N/A 13.2 9 N/A <5 N/A N/A N/A <0.005 N/A 289 N/A <1 N/A 5.97 N/A 516 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 3.9 N/A <5 N/A N/A N/A <0.005 N/A 355 N/A <1 N/A N/A N/A 35 N/A <0.05 N/A N/A
N/A N/A 4.2 N/A <5 N/A N/A N/A <0.005 N/A 193 N/A <1 N/A N/A N/A 19 N/A <0.05 N/A N/A
N/A N/A 4.3 N/A <5 N/A N/A N/A <0.005 N/A 108 N/A <1 N/A N/A N/A 16 N/A <0.05 N/A N/A
N/A N/A 4.2 N/A <5 N/A N/A N/A <0.005 N/A 27 N/A <1 N/A N/A N/A 13 N/A <0.05 N/A N/A
N/A N/A 4 N/A <5 N/A N/A N/A <0.005 N/A 844 N/A <1 N/A N/A N/A 14 N/A <0.05 N/A N/A
N/A 9.32 4.3 N/A <5 N/A N/A N/A <0.005 N/A 203 N/A <1 N/A 3.08 N/A 7 N/A <0.05 N/A N/A
N/A 8.95 3.9 N/A <5 N/A N/A N/A <0.005 N/A 90 N/A <1 N/A 2.95 N/A <5 N/A <0.05 N/A N/A
9.61 9.66 4.1 <5 <5 N/A N/A <0.005 <0.005 <10 99 <1 <1 3.23 3.25 <5 <5 <0.05 <0.05 N/A N/A
N/A 9.58 4.6 N/A <5 N/A N/A N/A <0.005 N/A 436 N/A <1 N/A 3.15 N/A 5 N/A <0.05 N/A N/A
N/A 9.78 4.4 N/A <5 N/A N/A N/A <0.005 N/A 29 N/A <1 N/A 3.24 N/A <5 N/A <0.05 N/A N/A
N/A 9.65 4.4 N/A <5 N/A N/A N/A <0.005 N/A 108 N/A <1 N/A 3.21 N/A <5 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 4.7 N/A <5 N/A N/A N/A <0.005 N/A 498 N/A <1 N/A N/A N/A 31 N/A <0.05 N/A N/A
N/A N/A 4.8 N/A <5 N/A N/A N/A <0.005 N/A 275 N/A <1 N/A N/A N/A 14 N/A <0.05 N/A N/A
N/A N/A 4.9 N/A <5 N/A N/A N/A <0.005 N/A 146 N/A <1 N/A N/A N/A 8 N/A <0.05 N/A N/A
N/A N/A 4.6 N/A <5 N/A N/A N/A <0.005 N/A 219 N/A <1 N/A N/A N/A 9 N/A <0.05 N/A N/A
N/A N/A 4.3 N/A <5 N/A N/A N/A <0.005 N/A 149 N/A <1 N/A N/A N/A 7 N/A <0.05 N/A N/A
N/A 15.4 4.7 N/A <5 N/A N/A N/A <0.005 N/A 75 N/A <1 N/A 4.07 N/A <5 N/A <0.05 N/A N/A
N/A 15 4.4 N/A <5 N/A N/A N/A <0.005 N/A 178 N/A <1 N/A 3.94 N/A 8 N/A <0.05 N/A N/A
15.8 16 4.2 <5 <5 N/A N/A <0.005 <0.005 <10 823 <1 <1 4.12 4.3 <5 21 <0.05 <0.05 N/A N/A
N/A 16.2 4.7 N/A <5 N/A N/A N/A <0.005 N/A 405 N/A <1 N/A 4.23 N/A 12 N/A <0.05 N/A N/A
N/A 15.8 4.6 N/A <5 N/A N/A N/A <0.005 N/A 307 N/A <1 N/A 4.17 N/A 10 N/A <0.05 N/A N/A
N/A 15.7 4.2 N/A <5 N/A N/A N/A <0.005 N/A 128 N/A <1 N/A 4.05 N/A <5 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 3.2 N/A <5 N/A N/A N/A <0.005 N/A 69 N/A <1 N/A N/A N/A 43 N/A <0.05 N/A N/A
N/A N/A 3.4 N/A <5 N/A N/A N/A <0.005 N/A 35 N/A <1 N/A N/A N/A 44 N/A <0.05 N/A N/A
200.8200.7 200.7 200.8 200.7 200.7
15
200.7 200.8 245.1 200.8
NE 50 1 NENE101*1 300
µg/L µg/L µg/L µg/L
MolydenumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercury
µg/Lmg/L µg/L µg/L mg/L µg/L
Tables - Page 11
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
AB-12S Compliance Residuum 11/1/2011
AB-12S Compliance Residuum 3/5/2012
AB-12S Compliance Residuum 7/5/2012
AB-12S Compliance Residuum 11/5/2012
AB-12S Compliance Residuum 3/5/2013
AB-12S Compliance Residuum 7/2/2013
AB-12S Compliance Residuum 11/6/2013
AB-12S Compliance Residuum 3/5/2014
AB-12S Compliance Residuum 7/7/2014
AB-12S Compliance Residuum 11/4/2014
AB-13D Compliance Bedrock 3/1/2011
AB-13D Compliance Bedrock 7/7/2011
AB-13D Compliance Bedrock 11/1/2011
AB-13D Compliance Bedrock 3/5/2012
AB-13D Compliance Bedrock 7/5/2012
AB-13D Compliance Bedrock 11/5/2012
AB-13D Compliance Bedrock 3/4/2013
AB-13D Compliance Bedrock 7/1/2013
AB-13D Compliance Bedrock 11/7/2013
AB-13D Compliance Bedrock 3/5/2014
AB-13D Compliance Bedrock 7/7/2014
AB-13D Compliance Bedrock 11/4/2014
AB-13S Compliance Residuum 3/1/2011
AB-13S Compliance Residuum 7/7/2011
AB-13S Compliance Residuum 11/1/2011
AB-13S Compliance Residuum 3/5/2012
AB-13S Compliance Residuum 7/5/2012
AB-13S Compliance Residuum 11/5/2012
AB-13S Compliance Residuum 3/4/2013
AB-13S Compliance Residuum 7/1/2013
AB-13S Compliance Residuum 11/7/2013
AB-13S Compliance Residuum 3/5/2014
AB-13S Compliance Residuum 7/7/2014
AB-13S Compliance Residuum 11/4/2014
AB-14D Compliance Bedrock 3/1/2011
AB-14D Compliance Bedrock 7/21/2011
AB-14D Compliance Bedrock 11/1/2011
AB-14D Compliance Bedrock 3/5/2012
AB-14D Compliance Bedrock 7/5/2012
AB-14D Compliance Bedrock 11/5/2012
AB-14D Compliance Bedrock 3/5/2013
AB-14D Compliance Bedrock 7/2/2013
AB-14D Compliance Bedrock 11/7/2013
AB-14D Compliance Bedrock 3/5/2014
AB-14D Compliance Bedrock 7/7/2014
AB-14D Compliance Bedrock 11/4/2014
AB-1R Compliance Transition (Saprolite)3/1/2011
AB-1R Compliance Transition (Saprolite)7/7/2011
AB-1R Compliance Transition (Saprolite)11/1/2011
AB-1R Compliance Transition (Saprolite)3/5/2012
AB-1R Compliance Transition (Saprolite)7/5/2012
AB-1R Compliance Transition (Saprolite)11/5/2012
AB-1R Compliance Transition (Saprolite)3/4/2013
AB-1R Compliance Transition (Saprolite)7/1/2013
AB-1R Compliance Transition (Saprolite)11/7/2013
AB-1R Compliance Transition (Saprolite)3/5/2014
AB-1R Compliance Transition (Saprolite)7/7/2014
AB-1R Compliance Transition (Saprolite)11/4/2014
AB-2 Voluntary Transition (Saprolite)11/2/2004
Chloride
mg/L
250
300
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total
200.8200.7 200.7 200.8 200.7 200.7
15
200.7 200.8 245.1 200.8
NE 50 1 NENE101*1 300
µg/L µg/L µg/L µg/L
MolydenumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercury
µg/Lmg/L µg/L µg/L mg/L µg/L
N/A N/A 3.2 N/A <5 N/A N/A N/A <0.005 N/A 31 N/A <1 N/A N/A N/A 54 N/A <0.05 N/A N/A
N/A N/A 3.1 N/A <5 N/A N/A N/A <0.005 N/A 59 N/A <1 N/A N/A N/A 49 N/A <0.05 N/A N/A
N/A N/A 3.1 N/A <5 N/A N/A N/A <0.005 N/A 56 N/A <1 N/A N/A N/A 53 N/A <0.05 N/A N/A
N/A 0.359 3.1 N/A <5 N/A N/A N/A <0.005 N/A 92 N/A <1 N/A 0.964 N/A 53 N/A <0.05 N/A N/A
N/A 0.298 2.8 N/A <5 N/A N/A N/A <0.005 N/A 35 N/A <1 N/A 0.94 N/A 44 N/A <0.05 N/A N/A
0.39 0.358 2.8 <5 <5 N/A N/A <0.005 <0.005 <10 237 <1 <1 1.01 1.07 39 47 <0.05 <0.05 N/A N/A
N/A 0.334 3 N/A <5 N/A N/A N/A <0.005 N/A 206 N/A <1 N/A 1.02 N/A 56 N/A <0.05 N/A N/A
N/A 0.369 3 N/A <5 N/A N/A N/A <0.005 N/A 175 N/A <1 N/A 1.1 N/A 44 N/A <0.05 N/A N/A
N/A 0.241 2.8 N/A <5 N/A N/A N/A <0.005 N/A 573 N/A <1 N/A 1.18 N/A 56 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 4.1 N/A <5 N/A N/A N/A <0.005 N/A 1540 N/A <1 N/A N/A N/A 240 N/A <0.05 N/A N/A
N/A N/A 8.1 N/A <5 N/A N/A N/A <0.005 N/A 391 N/A <1 N/A N/A N/A 57 N/A <0.05 N/A N/A
N/A N/A 4.2 N/A <5 N/A N/A N/A <0.005 N/A 641 N/A <1 N/A N/A N/A 30 N/A <0.05 N/A N/A
N/A N/A 4.6 N/A 5 N/A N/A N/A <0.005 N/A 1430 N/A <1 N/A N/A N/A 64 N/A <0.05 N/A N/A
N/A N/A 3.3 N/A 6 N/A N/A N/A 0.005 N/A 2010 N/A <1 N/A N/A N/A 74 N/A <0.05 N/A N/A
N/A 13.2 2.8 N/A 9 N/A N/A N/A 0.011 N/A 3100 N/A <1 N/A 5.53 N/A 110 N/A <0.05 N/A N/A
N/A 13.6 5 N/A <5 N/A N/A N/A <0.005 N/A 591 N/A <1 N/A 3.67 N/A 20 N/A <0.05 N/A N/A
15.2 15.3 8.2 <5 <5 N/A N/A <0.005 <0.005 <10 597 <1 <1 3.71 3.97 <5 15 <0.05 <0.05 N/A N/A
N/A 14 3 N/A <5 N/A N/A N/A <0.005 N/A 499 N/A <1 N/A 3.66 N/A 12 N/A <0.05 N/A N/A
N/A 15.5 9.5 N/A <5 N/A N/A N/A <0.005 N/A 220 N/A <1 N/A 3.8 N/A 7 N/A <0.05 N/A N/A
N/A 15.7 9.2 N/A <5 N/A N/A N/A <0.005 N/A 134 N/A <1 N/A 3.76 N/A 6 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 7.2 N/A <5 N/A N/A N/A <0.005 N/A 273 N/A <1 N/A N/A N/A 55 N/A <0.05 N/A N/A
N/A N/A 7.5 N/A <5 N/A N/A N/A <0.005 N/A 26 N/A <1 N/A N/A N/A 101 N/A <0.05 N/A N/A
N/A N/A 7.5 N/A <5 N/A N/A N/A <0.005 N/A 58 N/A <1 N/A N/A N/A 44 N/A <0.05 N/A N/A
N/A N/A 7.4 N/A <5 N/A N/A N/A <0.005 N/A 40 N/A <1 N/A N/A N/A 37 N/A <0.05 N/A N/A
N/A N/A 7.2 N/A <5 N/A N/A N/A <0.005 N/A 37 N/A <1 N/A N/A N/A 38 N/A <0.05 N/A N/A
N/A 3.58 7.2 N/A <5 N/A N/A N/A <0.005 N/A 107 N/A <1 N/A 2.81 N/A 18 N/A <0.05 N/A N/A
N/A 10.8 6 N/A <5 N/A N/A N/A <0.005 N/A 157 N/A <1 N/A 2.85 N/A 43 N/A <0.05 N/A N/A
4.25 4.37 6.6 <5 <5 N/A N/A <0.005 <0.005 <10 591 <1 <1 2.9 2.94 14 26 <0.05 <0.05 N/A N/A
N/A 4.06 7.7 N/A <5 N/A N/A N/A <0.005 N/A 324 N/A <1 N/A 2.99 N/A 21 N/A <0.05 N/A N/A
N/A 9.01 7.4 N/A <5 N/A N/A N/A <0.005 N/A 817 N/A <1 N/A 2.82 N/A 165 N/A <0.05 N/A N/A
N/A 4.85 8.2 N/A <5 N/A N/A N/A <0.005 N/A 553 N/A <1 N/A 3.11 N/A 49 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 9.4 N/A <5 N/A N/A N/A 0.069 N/A 8350 N/A <1 N/A N/A N/A 945 N/A <0.05 N/A N/A
N/A N/A 10 N/A <5 N/A N/A N/A 0.169 N/A 2780 N/A <1 N/A N/A N/A 601 N/A <0.05 N/A N/A
N/A N/A 9.8 N/A <5 N/A N/A N/A 0.219 N/A 659 N/A <1 N/A N/A N/A 326 N/A <0.05 N/A N/A
N/A N/A 11 N/A <5 N/A N/A N/A 0.236 N/A 227 N/A <1 N/A N/A N/A 133 N/A <0.05 N/A N/A
N/A N/A 9.8 N/A <5 N/A N/A N/A 0.13 N/A 301 N/A <1 N/A N/A N/A 115 N/A <0.05 N/A N/A
N/A 5.72 9.1 N/A <5 N/A N/A N/A 0.158 N/A 370 N/A <1 N/A 2.33 N/A 100 N/A <0.05 N/A N/A
N/A 5.54 9.4 N/A <5 N/A N/A N/A 0.146 N/A 229 N/A <1 N/A 2.29 N/A 69 N/A <0.05 N/A N/A
5.67 5.77 9.5 <5 <5 N/A N/A 0.106 0.098 79 191 <1 <1 2.32 2.39 52 52 <0.05 <0.05 N/A N/A
N/A 5.58 9.3 N/A <5 N/A N/A N/A 0.076 N/A 606 N/A <1 N/A 2.28 N/A 62 N/A <0.05 N/A N/A
N/A 5.88 10 N/A <5 N/A N/A N/A 0.067 N/A 88 N/A <1 N/A 2.42 N/A 41 N/A <0.05 N/A N/A
N/A 5.78 9.5 N/A <5 N/A N/A N/A 0.054 N/A 206 N/A <1 N/A 2.29 N/A 39 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 1.1 N/A 8 N/A N/A N/A <0.005 N/A 180 N/A <1 N/A N/A N/A 45 N/A <0.05 N/A N/A
N/A N/A 1.2 N/A <5 N/A N/A N/A <0.005 N/A 81 N/A <1 N/A N/A N/A 30 N/A <0.05 N/A N/A
N/A N/A 1.2 N/A 6 N/A N/A N/A <0.005 N/A 381 N/A <1 N/A N/A N/A 35 N/A <0.05 N/A N/A
N/A N/A 1.1 N/A <5 N/A N/A N/A <0.005 N/A 64 N/A <1 N/A N/A N/A 15 N/A <0.05 N/A N/A
N/A N/A 1.1 N/A <5 N/A N/A N/A <0.005 N/A 52 N/A <1 N/A N/A N/A 12 N/A <0.05 N/A N/A
N/A 12.8 1.1 N/A <5 N/A N/A N/A <0.005 N/A 122 N/A <1 N/A 2.83 N/A 13 N/A <0.05 N/A N/A
N/A 11.7 1 N/A <5 N/A N/A N/A <0.005 N/A 65 N/A <1 N/A 2.59 N/A 7 N/A <0.05 N/A N/A
12.9 12.3 1.1 <5 <5 N/A N/A <0.005 <0.005 <10 29 <1 <1 2.73 2.75 <5 6 <0.05 <0.05 N/A N/A
N/A 12.8 1.1 N/A <5 N/A N/A N/A <0.005 N/A 46 N/A <1 N/A 2.77 N/A 7 N/A <0.05 N/A N/A
N/A 15.2 1.2 N/A <5 N/A N/A N/A <0.005 N/A 62 N/A <1 N/A 2.99 N/A 6 N/A <0.05 N/A N/A
N/A 27.9 0.97 N/A <5 N/A N/A N/A <0.005 N/A 125 N/A <1 N/A 5.66 N/A 14 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 0.24 3.9 N/A <1 N/A N/A N/A <0.002 N/A 490 N/A <2 N/A 0.92 N/A 110 N/A <0.1 N/A N/A
Tables - Page 12
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
AB-2 Voluntary Transition (Saprolite)5/2/2005
AB-2 Voluntary Transition (Saprolite)11/16/2005
AB-2 Voluntary Transition (Saprolite)5/8/2006
AB-2 Voluntary Transition (Saprolite)11/13/2006
AB-2 Voluntary Transition (Saprolite)5/14/2007
AB-2 Voluntary Transition (Saprolite)11/7/2007
AB-2 Voluntary Transition (Saprolite)5/14/2008
AB-2 Voluntary Transition (Saprolite)11/3/2008
AB-2 Voluntary Transition (Saprolite)5/13/2009
AB-2 Voluntary Transition (Saprolite)11/3/2009
AB-2 Voluntary Transition (Saprolite)5/4/2010
AB-2 Voluntary Transition (Saprolite)3/1/2011
AB-2D Voluntary Partially Weathered Rock 11/2/2004
AB-2D Voluntary Partially Weathered Rock 5/2/2005
AB-2D Voluntary Partially Weathered Rock 11/16/2005
AB-2D Voluntary Partially Weathered Rock 5/8/2006
AB-2D Voluntary Partially Weathered Rock 11/13/2006
AB-2D Voluntary Partially Weathered Rock 5/14/2007
AB-2D Voluntary Partially Weathered Rock 11/7/2007
AB-2D Voluntary Partially Weathered Rock 5/14/2008
AB-2D Voluntary Partially Weathered Rock 11/3/2008
AB-2D Voluntary Partially Weathered Rock 5/13/2009
AB-2D Voluntary Partially Weathered Rock 11/3/2009
AB-2D Voluntary Partially Weathered Rock 5/4/2010
AB-2D Voluntary Partially Weathered Rock 3/1/2011
AB-4D Compliance Partially Weathered Rock 11/2/2004
AB-4D Compliance Partially Weathered Rock 5/2/2005
AB-4D Compliance Partially Weathered Rock 11/16/2005
AB-4D Compliance Partially Weathered Rock 5/8/2006
AB-4D Compliance Partially Weathered Rock 11/13/2006
AB-4D Compliance Partially Weathered Rock 5/14/2007
AB-4D Compliance Partially Weathered Rock 11/7/2007
AB-4D Compliance Partially Weathered Rock 5/14/2008
AB-4D Compliance Partially Weathered Rock 11/3/2008
AB-4D Compliance Partially Weathered Rock 5/13/2009
AB-4D Compliance Partially Weathered Rock 11/3/2009
AB-4D Compliance Partially Weathered Rock 5/4/2010
AB-4D Compliance Partially Weathered Rock 3/1/2011
AB-4D Compliance Partially Weathered Rock 7/7/2011
AB-4D Compliance Partially Weathered Rock 11/1/2011
AB-4D Compliance Partially Weathered Rock 3/5/2012
AB-4D Compliance Partially Weathered Rock 7/5/2012
AB-4D Compliance Partially Weathered Rock 11/5/2012
AB-4D Compliance Partially Weathered Rock 3/5/2013
AB-4D Compliance Partially Weathered Rock 7/2/2013
AB-4D Compliance Partially Weathered Rock 11/6/2013
AB-4D Compliance Partially Weathered Rock 3/5/2014
AB-4D Compliance Partially Weathered Rock 7/7/2014
AB-4D Compliance Partially Weathered Rock 11/4/2014
AB-4S (4)Compliance Transition (Saprolite)11/2/2004
AB-4S (4)Compliance Transition (Saprolite)5/2/2005
AB-4S (4)Compliance Transition (Saprolite)11/16/2005
AB-4S (4)Compliance Transition (Saprolite)5/8/2006
AB-4S (4)Compliance Transition (Saprolite)11/13/2006
AB-4S (4)Compliance Transition (Saprolite)5/14/2007
AB-4S (4)Compliance Transition (Saprolite)11/7/2007
AB-4S (4)Compliance Transition (Saprolite)5/14/2008
AB-4S (4)Compliance Transition (Saprolite)11/3/2008
AB-4S (4)Compliance Transition (Saprolite)5/13/2009
Chloride
mg/L
250
300
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total
200.8200.7 200.7 200.8 200.7 200.7
15
200.7 200.8 245.1 200.8
NE 50 1 NENE101*1 300
µg/L µg/L µg/L µg/L
MolydenumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercury
µg/Lmg/L µg/L µg/L mg/L µg/L
N/A N/A 2.6 N/A <1 N/A N/A N/A <0.002 N/A 180 N/A <2 N/A N/A N/A 170 N/A <0.1 N/A N/A
N/A 0.144 2.81 N/A <1 N/A N/A N/A <0.002 N/A 282 N/A <2 N/A 0.997 N/A 200 N/A <0.1 N/A N/A
N/A 0.133 2.75 N/A 1.72 N/A N/A N/A <0.002 N/A 83 N/A <2 N/A 0.973 N/A 155 N/A <0.1 N/A N/A
N/A 0.193 3.04 N/A <1 N/A N/A N/A <0.002 N/A 49 N/A <2 N/A 0.989 N/A 164 N/A <0.2 N/A N/A
N/A 0.179 2.71 N/A <1 N/A N/A N/A <0.002 N/A 34 N/A <2 N/A 1.023 N/A 111 N/A <0.1 N/A N/A
N/A 0.156 2.9 N/A <1 N/A N/A N/A <0.002 N/A 70 N/A <2 N/A 0.892 N/A 171 N/A <0.1 N/A N/A
N/A 0.147 3 N/A <1 N/A N/A N/A <0.002 N/A 107 N/A <2 N/A 0.952 N/A 115 N/A <0.05 N/A N/A
N/A 0.31 3.3 N/A <1 N/A N/A N/A <0.002 N/A 214 N/A <2 N/A 0.647 N/A 81 N/A <0.05 N/A N/A
N/A 0.351 3.5 N/A <1 N/A N/A N/A 0.001 N/A 190 N/A <1 N/A 0.658 N/A 59 N/A <0.05 N/A N/A
N/A 0.272 4.3 N/A <1 N/A N/A N/A <0.001 N/A 22.8 N/A <1 N/A 0.765 N/A 97 N/A <0.05 N/A N/A
N/A 0.423 3.2 N/A <1 N/A N/A N/A <0.001 N/A 95.7 N/A <1 N/A 0.944 N/A 59.2 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 6.93 1.8 N/A 2.7 N/A N/A N/A <0.002 N/A 130 N/A <2 N/A 2.31 N/A 23 N/A <0.1 N/A N/A
N/A N/A 1.5 N/A 2.6 N/A N/A N/A 0.003 N/A 100 N/A <2 N/A N/A N/A 14 N/A <0.1 N/A N/A
N/A 7.942 1.9 N/A 2.66 N/A N/A N/A <0.002 N/A 90 N/A <2 N/A 2.573 N/A <5 N/A <0.1 N/A N/A
N/A 6.93 1.89 N/A 3.91 N/A N/A N/A <0.002 N/A 199 N/A <2 N/A 2.293 N/A 10 N/A <0.1 N/A N/A
N/A 8.403 2.05 N/A 2.31 N/A N/A N/A <0.002 N/A 56 N/A <2 N/A 2.772 N/A 7 N/A <0.2 N/A N/A
N/A 6.999 1.75 N/A 2.51 N/A N/A N/A <0.002 N/A 16 N/A <2 N/A 2.271 N/A <5 N/A <0.1 N/A N/A
N/A 7.469 2.07 N/A 2.49 N/A N/A N/A <0.002 N/A 14 N/A <2 N/A 2.472 N/A <5 N/A <0.1 N/A N/A
N/A 6.43 1.9 N/A 1.95 N/A N/A N/A <0.002 N/A 15 N/A <2 N/A 2.04 N/A <5 N/A <0.05 N/A N/A
N/A 7.75 2 N/A 2.13 N/A N/A N/A <0.002 N/A 14 N/A <2 N/A 2.49 N/A <5 N/A <0.05 N/A N/A
N/A 6.27 1.9 N/A 2.1 N/A N/A N/A <0.001 N/A 14 N/A <1 N/A 1.93 N/A <5 N/A <0.05 N/A N/A
N/A 7.55 2.2 N/A 2 N/A N/A N/A <0.001 N/A 13 N/A <1 N/A 2.39 N/A <5 N/A <0.05 N/A N/A
N/A 6.47 2 N/A 2.4 N/A N/A N/A <0.002 N/A 28.6 N/A <1 N/A 1.95 N/A <5 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 9.68 6.1 N/A 4.1 N/A N/A N/A 0.004 N/A 750 N/A <2 N/A 3.25 N/A 110 N/A <0.1 N/A N/A
N/A N/A 5.4 N/A 4.3 N/A N/A N/A 0.044 N/A 200 N/A <2 N/A N/A N/A 74 N/A <0.1 N/A N/A
N/A 9.324 6.94 N/A 4 N/A N/A N/A 0.048 N/A 82 N/A <2 N/A 2.703 N/A 41 N/A <0.1 N/A N/A
N/A 9.686 5.49 N/A 5.48 N/A N/A N/A 0.057 N/A 179 N/A <2 N/A 2.865 N/A 36 N/A <0.1 N/A N/A
N/A 10.985 5.98 N/A 4.73 N/A N/A N/A 0.048 N/A 258 N/A <2 N/A 3.222 N/A 36 N/A <0.2 N/A N/A
N/A 10.222 6.37 N/A 3.74 N/A N/A N/A 0.036 N/A 20 N/A <2 N/A 3.007 N/A 10 N/A <0.1 N/A N/A
N/A 9.195 5.2 N/A 4.38 N/A N/A N/A 0.036 N/A 18 N/A <2 N/A 2.688 N/A 9 N/A <0.1 N/A N/A
N/A 9.51 5.8 N/A 3.42 N/A N/A N/A 0.025 N/A 11 N/A <2 N/A 2.81 N/A 7 N/A <0.05 N/A N/A
N/A 10.2 5.6 N/A 4.87 N/A N/A N/A 0.032 N/A <10 N/A <2 N/A 2.89 N/A 7 N/A <0.05 N/A N/A
N/A 9.72 5.3 N/A 4.7 N/A N/A N/A 0.026 N/A 16 N/A <1 N/A 2.83 N/A 5 N/A <0.05 N/A N/A
N/A 9.92 5.3 N/A 4.4 N/A N/A N/A 0.023 N/A <10 N/A <1 N/A 2.81 N/A <5 N/A <0.05 N/A N/A
N/A 10.3 7 N/A 4 N/A N/A N/A 0.025 N/A 42.2 N/A <1 N/A 2.94 N/A 5.38 N/A <0.05 N/A N/A
N/A N/A 5.4 N/A 6 N/A N/A N/A 0.022 N/A <10 N/A <1 N/A N/A N/A <5 N/A <0.05 N/A N/A
N/A N/A 6.6 N/A <5 N/A N/A N/A 0.016 N/A <10 N/A <1 N/A N/A N/A <5 N/A <0.05 N/A N/A
N/A N/A 5.9 N/A 5 N/A N/A N/A 0.019 N/A <10 N/A <1 N/A N/A N/A <5 N/A <0.05 N/A N/A
N/A N/A 5.3 N/A 6 N/A N/A N/A 0.018 N/A <10 N/A <1 N/A N/A N/A <5 N/A <0.05 N/A N/A
N/A N/A 5.9 N/A 5 N/A N/A N/A 0.018 N/A <10 N/A <1 N/A N/A N/A <5 N/A <0.05 N/A N/A
N/A 10.7 5.8 N/A 6 N/A N/A N/A 0.021 N/A 16 N/A <1 N/A 3.08 N/A <5 N/A <0.05 N/A N/A
N/A 11.2 5.2 N/A 7 N/A N/A N/A 0.02 N/A <10 N/A <1 N/A 3.26 N/A <5 N/A <0.05 N/A N/A
11.1 11.1 5.6 6 6 N/A N/A 0.018 0.019 <10 13 <1 <1 3.2 3.16 <5 <5 <0.05 <0.05 N/A N/A
N/A 12.3 6.7 N/A 6 N/A N/A N/A 0.02 N/A <10 N/A <1 N/A 3.43 N/A <5 N/A <0.05 N/A N/A
N/A 10.9 5.4 N/A 6 N/A N/A N/A 0.017 N/A 38 N/A <1 N/A 3.07 N/A <5 N/A <0.05 N/A N/A
N/A 12 6.7 N/A <5 N/A N/A N/A 0.019 N/A 23 N/A <1 N/A 3.34 N/A <5 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 4.3 8.8 N/A <1 N/A N/A N/A <0.002 N/A 1100 N/A <2 N/A 3.38 N/A 240 N/A <0.1 N/A N/A
N/A N/A 18 N/A 1 N/A N/A N/A 0.002 N/A 3600 N/A <2 N/A N/A N/A 380 N/A <0.1 N/A N/A
N/A 4.906 9.01 N/A <1 N/A N/A N/A <0.002 N/A 608 N/A <2 N/A 3.645 N/A 249 N/A <0.1 N/A N/A
N/A 6.729 8.64 N/A 2.32 N/A N/A N/A <0.002 N/A 806 N/A <2 N/A 4.605 N/A 85 N/A <0.1 N/A N/A
N/A 11.453 7.65 N/A <1 N/A N/A N/A <0.002 N/A 705 N/A <2 N/A 7.086 N/A 61 N/A <0.2 N/A N/A
N/A 12.163 8.82 N/A <1 N/A N/A N/A <0.002 N/A 120 N/A <2 N/A 7.156 N/A 32 N/A <0.1 N/A N/A
N/A 11.188 8.67 N/A <1 N/A N/A N/A <0.002 N/A 625 N/A <2 N/A 6.918 N/A 167 N/A <0.1 N/A N/A
N/A 10.4 7.7 N/A <1 N/A N/A N/A <0.002 N/A 1340 N/A <2 N/A 5.79 N/A 60 N/A <0.05 N/A N/A
N/A 10.7 8.5 N/A <1 N/A N/A N/A <0.002 N/A 244 N/A <2 N/A 5.68 N/A 114 N/A <0.05 N/A N/A
N/A 10.1 6.1 N/A <1 N/A N/A N/A <0.001 N/A 338 N/A <1 N/A 5.42 N/A 9 N/A <0.05 N/A N/A
Tables - Page 13
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
AB-4S (4)Compliance Transition (Saprolite)11/3/2009
AB-4S (4)Compliance Transition (Saprolite)5/4/2010
AB-4S (4)Compliance Transition (Saprolite)3/1/2011
AB-4S (4)Compliance Transition (Saprolite)7/7/2011
AB-4S (4)Compliance Transition (Saprolite)11/1/2011
AB-4S (4)Compliance Transition (Saprolite)3/5/2012
AB-4S (4)Compliance Transition (Saprolite)7/5/2012
AB-4S (4)Compliance Transition (Saprolite)11/5/2012
AB-4S (4)Compliance Transition (Saprolite)3/5/2013
AB-4S (4)Compliance Transition (Saprolite)7/2/2013
AB-4S (4)Compliance Transition (Saprolite)11/6/2013
AB-4S (4)Compliance Transition (Saprolite)3/5/2014
AB-4S (4)Compliance Transition (Saprolite)7/7/2014
AB-4S (4)Compliance Transition (Saprolite)11/4/2014
AB-5 Voluntary Transition (Saprolite)11/2/2004
AB-5 Voluntary Transition (Saprolite)5/2/2005
AB-5 Voluntary Transition (Saprolite)11/16/2005
AB-5 Voluntary Transition (Saprolite)5/8/2006
AB-5 Voluntary Transition (Saprolite)11/13/2006
AB-5 Voluntary Transition (Saprolite)5/14/2007
AB-5 Voluntary Transition (Saprolite)11/7/2007
AB-5 Voluntary Transition (Saprolite)5/14/2008
AB-5 Voluntary Transition (Saprolite)11/3/2008
AB-5 Voluntary Transition (Saprolite)5/13/2009
AB-5 Voluntary Transition (Saprolite)11/3/2009
AB-5 Voluntary Transition (Saprolite)5/4/2010
AB-5 Voluntary Transition (Saprolite)3/1/2011
AB-5 Voluntary Transition (Saprolite)7/7/2011
AB-5 Voluntary Transition (Saprolite)11/1/2011
AB-6A Voluntary Alluvium 3/21/2005
AB-6A Voluntary Alluvium 5/2/2005
AB-6A Voluntary Alluvium 11/16/2005
AB-6A Voluntary Alluvium 5/8/2006
AB-6A Voluntary Alluvium 11/13/2006
AB-6A Voluntary Alluvium 5/14/2007
AB-6A Voluntary Alluvium 11/7/2007
AB-6A Voluntary Alluvium 5/14/2008
AB-6A Voluntary Alluvium 11/3/2008
AB-6A Voluntary Alluvium 5/13/2009
AB-6A Voluntary Alluvium 11/3/2009
AB-6A Voluntary Alluvium 5/4/2010
AB-6A Voluntary Alluvium 3/1/2011
AB-6A Voluntary Alluvium 7/7/2011
AB-6A Voluntary Alluvium 11/1/2011
AB-6R Voluntary Transition (Saprolite)3/21/2005
AB-6R Voluntary Transition (Saprolite)5/2/2005
AB-6R Voluntary Transition (Saprolite)11/16/2005
AB-6R Voluntary Transition (Saprolite)5/8/2006
AB-6R Voluntary Transition (Saprolite)11/13/2006
AB-6R Voluntary Transition (Saprolite)5/14/2007
AB-6R Voluntary Transition (Saprolite)11/7/2007
AB-6R Voluntary Transition (Saprolite)5/14/2008
AB-6R Voluntary Transition (Saprolite)11/3/2008
AB-6R Voluntary Transition (Saprolite)5/13/2009
AB-6R Voluntary Transition (Saprolite)11/3/2009
AB-6R Voluntary Transition (Saprolite)5/4/2010
AB-6R Voluntary Transition (Saprolite)3/1/2011
AB-6R Voluntary Transition (Saprolite)7/7/2011
AB-6R Voluntary Transition (Saprolite)11/1/2011
Chloride
mg/L
250
300
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total
200.8200.7 200.7 200.8 200.7 200.7
15
200.7 200.8 245.1 200.8
NE 50 1 NENE101*1 300
µg/L µg/L µg/L µg/L
MolydenumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercury
µg/Lmg/L µg/L µg/L mg/L µg/L
N/A 9.12 4.9 N/A <1 N/A N/A N/A 0.001 N/A 130 N/A <1 N/A 5.39 N/A 17.2 N/A <0.05 N/A N/A
N/A 10.8 4.9 N/A <2 N/A N/A N/A <0.002 N/A 126 N/A <1 N/A 5.5 N/A 21 N/A <0.05 N/A N/A
N/A N/A 8.5 N/A <5 N/A N/A N/A <0.005 N/A 142 N/A <1 N/A N/A N/A 12 N/A <0.05 N/A N/A
N/A N/A 4.7 N/A <5 N/A N/A N/A <0.005 N/A 114 N/A <1 N/A N/A N/A 6 N/A <0.05 N/A N/A
N/A N/A 5.8 N/A <5 N/A N/A N/A <0.005 N/A 75 N/A <1 N/A N/A N/A 64 N/A <0.05 N/A N/A
N/A N/A 5.3 N/A <5 N/A N/A N/A <0.005 N/A 119 N/A <1 N/A N/A N/A <5 N/A <0.05 N/A N/A
N/A N/A 3.8 N/A <5 N/A N/A N/A <0.005 N/A 98 N/A <1 N/A N/A N/A 45 N/A <0.05 N/A N/A
N/A 8.9 4.5 N/A <5 N/A N/A N/A <0.005 N/A 97 N/A <1 N/A 4.86 N/A 92 N/A <0.05 N/A N/A
N/A 9.47 4.5 N/A <5 N/A N/A N/A <0.005 N/A 293 N/A <1 N/A 5.05 N/A 14 N/A <0.05 N/A N/A
13.9 13.9 4 <5 <5 N/A N/A <0.005 <0.005 163 524 <1 <1 6.21 6.25 86 88 <0.05 <0.05 N/A N/A
N/A 13.8 4.8 N/A <5 N/A N/A N/A <0.005 N/A 555 N/A <1 N/A 6.56 N/A 285 N/A <0.05 N/A N/A
N/A 11.1 4.3 N/A <5 N/A N/A N/A <0.005 N/A 314 N/A <1 N/A 5.21 N/A 9 N/A <0.05 N/A N/A
N/A 11.1 3.3 N/A <5 N/A N/A N/A <0.005 N/A 378 N/A <1 N/A 5.41 N/A 201 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 1.31 4.5 N/A 1.2 N/A N/A N/A <0.002 N/A 2400 N/A <2 N/A 1.65 N/A 200 N/A <0.1 N/A N/A
N/A N/A 3.2 N/A 1.2 N/A N/A N/A <0.002 N/A 620 N/A <2 N/A N/A N/A 190 N/A <0.1 N/A N/A
N/A 1.347 3.17 N/A 1.15 N/A N/A N/A <0.002 N/A 382 N/A <2 N/A 1.245 N/A 128 N/A <0.1 N/A N/A
N/A 1.336 3.43 N/A 1.56 N/A N/A N/A <0.002 N/A 342 N/A <2 N/A 1.195 N/A 93 N/A <0.1 N/A N/A
N/A 1.258 3.54 N/A <1 N/A N/A N/A <0.002 N/A 539 N/A <2 N/A 1.285 N/A 206 N/A <0.2 N/A N/A
N/A 1.309 3.34 N/A 1.78 N/A N/A N/A <0.002 N/A 234 N/A <2 N/A 1.221 N/A 56 N/A <0.1 N/A N/A
N/A 1.358 3.52 N/A 2.08 N/A N/A N/A <0.002 N/A 5525 N/A <2 N/A 2.744 N/A 299 N/A <0.1 N/A N/A
N/A 1.81 3.4 N/A 1.02 N/A N/A N/A <0.002 N/A 1700 N/A <2 N/A 1.42 N/A 68 N/A <0.05 N/A N/A
N/A 1.61 3.6 N/A 1.49 N/A N/A N/A <0.002 N/A 1140 N/A <2 N/A 1.3 N/A 60 N/A <0.05 N/A N/A
N/A 1.43 5.8 N/A <1 N/A N/A N/A <0.001 N/A 317 N/A <1 N/A 1.06 N/A 26 N/A <0.05 N/A N/A
N/A 1.34 3.4 N/A 1.1 N/A N/A N/A <0.001 N/A 316 N/A <1 N/A 1.04 N/A 25.7 N/A <0.05 N/A N/A
N/A 1.33 3.4 N/A <2 N/A N/A N/A <0.002 N/A 1420 N/A <1 N/A 1.28 N/A 51 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 8.578 3.71 N/A 33.83 N/A N/A N/A <0.002 N/A 435 N/A <2 N/A 2.816 N/A 57 N/A <0.1 N/A N/A
N/A N/A 4.8 N/A 37 N/A N/A N/A <0.002 N/A 710 N/A <2 N/A N/A N/A 120 N/A <0.1 N/A N/A
N/A 9.011 4.92 N/A 37.23 N/A N/A N/A <0.002 N/A 497 N/A <2 N/A 2.863 N/A 52 N/A <0.1 N/A N/A
N/A 8.959 5.32 N/A 41.41 N/A N/A N/A <0.002 N/A 110 N/A <2 N/A 2.776 N/A 28 N/A <0.1 N/A N/A
N/A 9.412 6.52 N/A 37.08 N/A N/A N/A <0.002 N/A 175 N/A <2 N/A 2.996 N/A 26 N/A <0.2 N/A N/A
N/A 9.258 6.31 N/A 32.34 N/A N/A N/A <0.002 N/A 53 N/A <2 N/A 2.948 N/A 25 N/A <0.1 N/A N/A
N/A 8.989 7.13 N/A 37.97 N/A N/A N/A <0.002 N/A 65 N/A <2 N/A 2.849 N/A 15 N/A <0.1 N/A N/A
N/A 9.18 7 N/A 23.9 N/A N/A N/A <0.002 N/A 204 N/A <2 N/A 2.97 N/A 24 N/A <0.05 N/A N/A
N/A 9.52 7.4 N/A 30.4 N/A N/A N/A <0.002 N/A 148 N/A <2 N/A 2.97 N/A 28 N/A <0.05 N/A N/A
N/A 9.38 7.3 N/A 29 N/A N/A N/A <0.001 N/A 83 N/A <1 N/A 2.96 N/A 22 N/A <0.05 N/A N/A
N/A 9.69 7.4 N/A 26.4 N/A N/A N/A <0.001 N/A 109 N/A <1 N/A 3 N/A 23.3 N/A <0.05 N/A N/A
N/A 9.94 7.4 N/A 28.9 N/A N/A N/A <0.001 N/A 77.6 N/A <1 N/A 3.03 N/A 14.1 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 8.716 3 N/A 14 N/A N/A N/A 0.003 N/A 3471 N/A <2 N/A 3.365 N/A 150 N/A <0.1 N/A N/A
N/A N/A 3.3 N/A 15 N/A N/A N/A <0.002 N/A 710 N/A <2 N/A N/A N/A 120 N/A <0.1 N/A N/A
N/A 9.523 4.51 N/A 17.14 N/A N/A N/A 0.003 N/A 3320 N/A <2 N/A 3.745 N/A 152 N/A <0.1 N/A N/A
N/A 9.738 4.85 N/A 17.17 N/A N/A N/A <0.002 N/A 873 N/A <2 N/A 3.182 N/A 92 N/A <0.1 N/A N/A
N/A 10.261 5.89 N/A 15.7 N/A N/A N/A <0.002 N/A 629 N/A <2 N/A 3.398 N/A 177 N/A <0.2 N/A N/A
N/A 9.752 5.61 N/A 15.43 N/A N/A N/A <0.002 N/A 188 N/A <2 N/A 3.077 N/A 80 N/A <0.1 N/A N/A
N/A 9.769 6.21 N/A 19.64 N/A N/A N/A <0.002 N/A 2067 N/A <2 N/A 3.69 N/A 131 N/A <0.1 N/A N/A
N/A 9.56 6.1 N/A 12.7 N/A N/A N/A <0.002 N/A 724 N/A <2 N/A 3.19 N/A 120 N/A <0.05 N/A N/A
N/A 10.2 6.4 N/A 19.8 N/A N/A N/A <0.002 N/A 358 N/A <2 N/A 3.18 N/A 84 N/A <0.05 N/A N/A
N/A 9.8 6.1 N/A 18.3 N/A N/A N/A <0.001 N/A 145 N/A <1 N/A 3.07 N/A 78 N/A <0.05 N/A N/A
N/A 10.1 8.1 N/A 16.5 N/A N/A N/A <0.001 N/A 243 N/A <1 N/A 3.12 N/A 64.9 N/A <0.05 N/A N/A
N/A 10.1 6.4 N/A 17 N/A N/A N/A <0.001 N/A 420 N/A <1 N/A 3.13 N/A 106 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tables - Page 14
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
AB-8 Voluntary Transition (Saprolite)3/21/2005
AB-8 Voluntary Transition (Saprolite)5/2/2005
AB-8 Voluntary Transition (Saprolite)11/16/2005
AB-8 Voluntary Transition (Saprolite)5/8/2006
AB-8 Voluntary Transition (Saprolite)11/13/2006
AB-8 Voluntary Transition (Saprolite)5/14/2007
AB-8 Voluntary Transition (Saprolite)11/7/2007
AB-8 Voluntary Transition (Saprolite)5/14/2008
AB-8 Voluntary Transition (Saprolite)11/3/2008
AB-8 Voluntary Transition (Saprolite)5/13/2009
AB-8 Voluntary Transition (Saprolite)11/3/2009
AB-8 Voluntary Transition (Saprolite)5/4/2010
AB-9D Compliance Bedrock 3/1/2011
AB-9D Compliance Bedrock 7/7/2011
AB-9D Compliance Bedrock 11/1/2011
AB-9D Compliance Bedrock 3/5/2012
AB-9D Compliance Bedrock 7/5/2012
AB-9D Compliance Bedrock 11/5/2012
AB-9D Compliance Bedrock 3/4/2013
AB-9D Compliance Bedrock 7/1/2013
AB-9D Compliance Bedrock 11/6/2013
AB-9D Compliance Bedrock 3/5/2014
AB-9D Compliance Bedrock 7/7/2014
AB-9D Compliance Bedrock 11/4/2014
AB-9S Compliance Transition (Saprolite)3/1/2011
AB-9S Compliance Transition (Saprolite)7/7/2011
AB-9S Compliance Transition (Saprolite)11/1/2011
AB-9S Compliance Transition (Saprolite)3/5/2012
AB-9S Compliance Transition (Saprolite)7/5/2012
AB-9S Compliance Transition (Saprolite)11/5/2012
AB-9S Compliance Transition (Saprolite)3/4/2013
AB-9S Compliance Transition (Saprolite)7/1/2013
AB-9S Compliance Transition (Saprolite)11/6/2013
AB-9S Compliance Transition (Saprolite)3/5/2014
AB-9S Compliance Transition (Saprolite)7/7/2014
AB-9S Compliance Transition (Saprolite)11/4/2014
Chloride
mg/L
250
300
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total
200.8200.7 200.7 200.8 200.7 200.7
15
200.7 200.8 245.1 200.8
NE 50 1 NENE101*1 300
µg/L µg/L µg/L µg/L
MolydenumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercury
µg/Lmg/L µg/L µg/L mg/L µg/L
N/A 21.18 4.4 N/A 2.55 N/A N/A N/A 0.003 N/A 1168 N/A <2 N/A 4.111 N/A 44 N/A <0.1 N/A N/A
N/A N/A 6.1 N/A 2.3 N/A N/A N/A <0.002 N/A 290 N/A <2 N/A N/A N/A 12 N/A <0.1 N/A N/A
N/A 20.407 6.62 N/A 1.89 N/A N/A N/A <0.002 N/A 105 N/A <2 N/A 3.626 N/A <5 N/A <0.1 N/A N/A
N/A 20.092 6.78 N/A 2.98 N/A N/A N/A <0.002 N/A 175 N/A <2 N/A 3.653 N/A 7 N/A <0.1 N/A N/A
N/A 21.14 8.21 N/A 1.6 N/A N/A N/A <0.002 N/A 79 N/A <2 N/A 3.197 N/A <5 N/A <0.2 N/A N/A
N/A 20.996 7.81 N/A 1.68 N/A N/A N/A <0.002 N/A 21 N/A <2 N/A 3.846 N/A <5 N/A <0.1 N/A N/A
N/A 19.974 8.63 N/A 2.14 N/A N/A N/A <0.002 N/A 94 N/A <2 N/A 3.62 N/A 5 N/A <0.1 N/A N/A
N/A 19.7 8.2 N/A 1.12 N/A N/A N/A <0.002 N/A 32 N/A <2 N/A 3.65 N/A <5 N/A <0.05 N/A N/A
N/A 21.1 9.1 N/A 1.76 N/A N/A N/A <0.002 N/A 17 N/A <2 N/A 3.74 N/A <5 N/A <0.05 N/A N/A
N/A 21.1 8.8 N/A 1.2 N/A N/A N/A <0.001 N/A <10 N/A <1 N/A 3.85 N/A <5 N/A <0.05 N/A N/A
N/A 21.5 9 N/A 1.3 N/A N/A N/A <0.001 N/A 12.2 N/A <1 N/A 3.83 N/A <5 N/A <0.05 N/A N/A
N/A 22 9.2 N/A 1.3 N/A N/A N/A <0.001 N/A 33.9 N/A <1 N/A 3.9 N/A <5 N/A <0.05 N/A N/A
N/A N/A 8.8 N/A <5 N/A N/A N/A <0.005 N/A 909 N/A <1 N/A N/A N/A 95 N/A <0.05 N/A N/A
N/A N/A 9.1 N/A <5 N/A N/A N/A <0.005 N/A 229 N/A <1 N/A N/A N/A 43 N/A <0.05 N/A N/A
N/A N/A 9 N/A <5 N/A N/A N/A <0.005 N/A 88 N/A <1 N/A N/A N/A 29 N/A <0.05 N/A N/A
N/A N/A 8.7 N/A <5 N/A N/A N/A <0.005 N/A 174 N/A <1 N/A N/A N/A 33 N/A <0.05 N/A N/A
N/A N/A 8.4 N/A <5 N/A N/A N/A <0.005 N/A 157 N/A <1 N/A N/A N/A 32 N/A <0.05 N/A N/A
N/A 26 8.5 N/A <5 N/A N/A N/A <0.005 N/A 138 N/A <1 N/A 6.01 N/A 29 N/A <0.05 N/A N/A
N/A 25.2 8.3 N/A <5 N/A N/A N/A <0.005 N/A 167 N/A <1 N/A 5.72 N/A 28 N/A <0.05 N/A N/A
26.5 26.6 8.1 <5 <5 N/A N/A <0.005 <0.005 <10 234 <1 <1 5.97 6.07 21 27 <0.05 <0.05 N/A N/A
N/A 27.2 8.8 N/A <5 N/A N/A N/A <0.005 N/A 356 N/A <1 N/A 6.19 N/A 28 N/A <0.05 N/A N/A
N/A 27.8 8.5 N/A <5 N/A N/A N/A <0.005 N/A 190 N/A <1 N/A 6.26 N/A 19 N/A <0.05 N/A N/A
N/A 27.1 8.1 N/A <5 N/A N/A N/A <0.005 N/A 258 N/A <1 N/A 6.18 N/A 23 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 9.6 N/A <5 N/A N/A N/A <0.005 N/A 10500 N/A <1 N/A N/A N/A 9690 N/A <0.05 N/A N/A
N/A N/A 9.1 N/A <5 N/A N/A N/A <0.005 N/A 9740 N/A <1 N/A N/A N/A 10200 N/A <0.05 N/A N/A
N/A N/A 9.5 N/A <5 N/A N/A N/A <0.005 N/A 9420 N/A <1 N/A N/A N/A 9320 N/A <0.05 N/A N/A
N/A N/A 9.5 N/A <5 N/A N/A N/A <0.005 N/A 7910 N/A <1 N/A N/A N/A 10200 N/A <0.05 N/A N/A
N/A N/A 9.6 N/A <5 N/A N/A N/A <0.005 N/A 10400 N/A <1 N/A N/A N/A 10200 N/A <0.05 N/A N/A
N/A 10.9 9.5 N/A <5 N/A N/A N/A <0.005 N/A 9880 N/A <1 N/A 5.95 N/A 9680 N/A <0.05 N/A N/A
N/A 10.3 9.2 N/A <5 N/A N/A N/A <0.005 N/A 6910 N/A <1 N/A 5.62 N/A 9370 N/A <0.05 N/A N/A
11.1 11.1 8.9 <5 <5 N/A N/A <0.005 <0.005 8600 9040 <1 <1 6.09 6.06 9690 9650 <0.05 <0.05 N/A N/A
N/A 11 9.7 N/A <5 N/A N/A N/A <0.005 N/A 9320 N/A <1 N/A 5.84 N/A 9430 N/A <0.05 N/A N/A
N/A 11.4 9.4 N/A <5 N/A N/A N/A <0.005 N/A 5600 N/A <1 N/A 6.21 N/A 10000 N/A <0.05 N/A N/A
N/A 10.7 9.1 N/A <5 N/A N/A N/A <0.005 N/A 9720 N/A <1 N/A 5.84 N/A 9590 N/A <0.05 N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tables - Page 15
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
AB-1 Compliance Transition (Saprolite)11/2/2004
AB-1 Compliance Transition (Saprolite)5/2/2005
AB-1 Compliance Transition (Saprolite)11/16/2005
AB-1 Compliance Transition (Saprolite)5/8/2006
AB-1 Compliance Transition (Saprolite)11/13/2006
AB-1 Compliance Transition (Saprolite)5/14/2007
AB-1 Compliance Transition (Saprolite)11/7/2007
AB-1 Compliance Transition (Saprolite)5/14/2008
AB-1 Compliance Transition (Saprolite)5/4/2010
AB-10D Compliance Bedrock 3/1/2011
AB-10D Compliance Bedrock 7/7/2011
AB-10D Compliance Bedrock 11/1/2011
AB-10D Compliance Bedrock 3/5/2012
AB-10D Compliance Bedrock 7/5/2012
AB-10D Compliance Bedrock 11/5/2012
AB-10D Compliance Bedrock 3/4/2013
AB-10D Compliance Bedrock 7/1/2013
AB-10D Compliance Bedrock 11/6/2013
AB-10D Compliance Bedrock 3/5/2014
AB-10D Compliance Bedrock 7/7/2014
AB-10D Compliance Bedrock 11/4/2014
AB-10S Compliance Residuum 3/1/2011
AB-10S Compliance Residuum 7/7/2011
AB-10S Compliance Residuum 11/1/2011
AB-10S Compliance Residuum 3/5/2012
AB-10S Compliance Residuum 7/5/2012
AB-10S Compliance Residuum 11/5/2012
AB-10S Compliance Residuum 3/4/2013
AB-10S Compliance Residuum 7/1/2013
AB-10S Compliance Residuum 11/6/2013
AB-10S Compliance Residuum 3/5/2014
AB-10S Compliance Residuum 7/7/2014
AB-10S Compliance Residuum 11/4/2014
AB-11D Compliance Bedrock 3/1/2011
AB-11D Compliance Bedrock 7/7/2011
AB-11D Compliance Bedrock 11/1/2011
AB-11D Compliance Bedrock 3/5/2012
AB-11D Compliance Bedrock 7/5/2012
AB-11D Compliance Bedrock 11/5/2012
AB-11D Compliance Bedrock 3/5/2013
AB-11D Compliance Bedrock 7/2/2013
AB-11D Compliance Bedrock 11/6/2013
AB-11D Compliance Bedrock 3/5/2014
AB-11D Compliance Bedrock 7/7/2014
AB-11D Compliance Bedrock 11/4/2014
AB-12D Compliance Bedrock 3/1/2011
AB-12D Compliance Bedrock 7/7/2011
AB-12D Compliance Bedrock 11/1/2011
AB-12D Compliance Bedrock 3/5/2012
AB-12D Compliance Bedrock 7/5/2012
AB-12D Compliance Bedrock 11/5/2012
AB-12D Compliance Bedrock 3/5/2013
AB-12D Compliance Bedrock 7/2/2013
AB-12D Compliance Bedrock 11/6/2013
AB-12D Compliance Bedrock 3/5/2014
AB-12D Compliance Bedrock 7/7/2014
AB-12D Compliance Bedrock 11/4/2014
AB-12S Compliance Residuum 3/1/2011
AB-12S Compliance Residuum 7/7/2011
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
Nitrate as N Strontium Sulfate TDS TOC TOX TSS
mg-N/L mg/L mg/L mg/L mg/L µg/L mg/L
10 NE 250 500 NE NE NE
300.0 300.0 2540C 5310B 2450D
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Total Total Total Dissolved Total Total Total Total Dissolved Total
N/A N/A 0.04 N/A 2.75 N/A <2 N/A 3.826 N/A 8.8 54 N/A N/A 1.8 17 N/A N/A <0.02
N/A N/A 0.21 N/A N/A N/A <2 N/A N/A N/A 4.2 60 N/A N/A 0.65 <20 N/A N/A <0.02
N/A N/A 0.25 N/A 1.93 N/A <2 N/A 2.587 N/A 1.07 56 N/A N/A 0.27 22.8 N/A N/A <0.005
N/A 2.41 0.25 N/A 3.02 N/A <2 N/A 2.48 N/A 0.76 70 N/A N/A 0.36 <1000 N/A N/A 0.02
N/A 2.67 0.23 N/A 1.92 N/A <2 N/A 2.475 N/A 0.53 68 N/A N/A 0.45 <1000 N/A N/A 0.015
N/A <2 0.25 N/A 1.52 N/A <2 N/A 2.416 N/A 0.39 40 N/A N/A 0.42 <1000 N/A N/A <0.005
N/A <2 0.26 N/A 1.68 N/A <2 N/A 2.294 N/A 0.43 77 N/A N/A 0.25 <1000 N/A N/A 0.006
N/A 2.8 0.2 N/A 1.65 N/A <2 N/A 2.44 N/A 0.36 57 N/A N/A 0.119 <20 N/A N/A 0.008
N/A 4.8 0.22 N/A 5.11 N/A <1 N/A 2.7 N/A 0.49 210 N/A N/A 0.342 <100 N/A N/A 0.04
N/A <5 <0.1 N/A N/A N/A <1 N/A N/A N/A 20 180 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 20 150 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 20 150 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.02 N/A N/A N/A <1 N/A N/A N/A 20 142 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 20 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.44 N/A <1 N/A 8.93 N/A 20 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.4 N/A <1 N/A 8.51 N/A 19 140 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 <0.023 1.46 1.47 <1 <1 9.14 9.04 N/A 19 150 <0.2 <0.2 N/A N/A <5 <0.005 <0.005
N/A <5 <0.023 N/A 1.56 N/A <1 N/A 9.23 N/A 20 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.5 N/A <1 N/A 9.18 N/A 20 150 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.49 N/A <1 N/A 9.07 N/A 20 140 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A <5 <0.1 N/A N/A N/A <1 N/A N/A N/A 14 89 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 16 93 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 14 99 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.07 N/A N/A N/A <1 N/A N/A N/A 16 107 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 15 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.63 N/A <1 N/A 10.1 N/A 15 89 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A 1.49 N/A <1 N/A 9.79 N/A 14 92 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 <0.023 1.61 1.57 <1 <1 10.4 10.1 N/A 15 96 <0.2 <0.2 N/A N/A <5.1 <0.005 <0.005
N/A <5 <0.023 N/A 1.7 N/A <1 N/A 10.6 N/A 16 110 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.07 N/A 1.62 N/A <1 N/A 10.8 N/A 16 100 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.6 N/A <1 N/A 10.5 N/A 16 98 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A <5 <0.1 N/A N/A N/A <1 N/A N/A N/A 0.31 110 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.04 N/A N/A N/A <1 N/A N/A N/A 0.35 140 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.04 N/A N/A N/A <1 N/A N/A N/A 0.37 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A N/A N/A <1 N/A N/A N/A 0.44 93 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A N/A N/A <1 N/A N/A N/A 0.43 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A 2.69 N/A <1 N/A 8.17 N/A 0.39 100 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A 2.51 N/A <1 N/A 7.77 N/A 0.32 91 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 0.05 2.58 2.63 <1 <1 8.1 8.22 N/A 0.31 97 <0.2 <0.2 N/A N/A <5 <0.005 0.005
N/A <5 0.06 N/A 2.7 N/A <1 N/A 8.22 N/A 0.4 91 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A 2.64 N/A <1 N/A 8.29 N/A 0.31 100 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A 2.58 N/A <1 N/A 8.22 N/A 0.31 89 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A <5 1.7 N/A N/A N/A <1 N/A N/A N/A 5.4 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.6 N/A N/A N/A <1 N/A N/A N/A 5.1 140 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.6 N/A N/A N/A <1 N/A N/A N/A 5 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.7 N/A N/A N/A <1 N/A N/A N/A 4.8 126 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.7 N/A N/A N/A <1 N/A N/A N/A 5.1 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.7 N/A 2.34 N/A <1 N/A 7.4 N/A 5.2 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.7 N/A 2.33 N/A 1.13 N/A 7.25 N/A 4.9 120 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 1.7 2.38 2.46 <1 <1 7.63 7.6 N/A 4.7 120 <0.2 <0.2 N/A N/A 22 <0.005 0.006
N/A <5 1.8 N/A 2.5 N/A <1 N/A 7.68 N/A 5 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.8 N/A 2.32 N/A <1 N/A 7.49 N/A 4.8 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.7 N/A 2.29 N/A <1 N/A 7.39 N/A 4.4 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A <5 <0.1 N/A N/A N/A <1 N/A N/A N/A 0.27 15 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 0.2 45 N/A <0.2 N/A N/A N/A N/A <0.005
200.7 200.7
1100NE
200.8 200.7 200.8 200.7
20 NE 0.2*
µg/L mg/L ug/L mg/Lµg/L mg/L
Selenium Sodium Thallium ZincNickelPotassium
Tables - Page 16
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
AB-12S Compliance Residuum 11/1/2011
AB-12S Compliance Residuum 3/5/2012
AB-12S Compliance Residuum 7/5/2012
AB-12S Compliance Residuum 11/5/2012
AB-12S Compliance Residuum 3/5/2013
AB-12S Compliance Residuum 7/2/2013
AB-12S Compliance Residuum 11/6/2013
AB-12S Compliance Residuum 3/5/2014
AB-12S Compliance Residuum 7/7/2014
AB-12S Compliance Residuum 11/4/2014
AB-13D Compliance Bedrock 3/1/2011
AB-13D Compliance Bedrock 7/7/2011
AB-13D Compliance Bedrock 11/1/2011
AB-13D Compliance Bedrock 3/5/2012
AB-13D Compliance Bedrock 7/5/2012
AB-13D Compliance Bedrock 11/5/2012
AB-13D Compliance Bedrock 3/4/2013
AB-13D Compliance Bedrock 7/1/2013
AB-13D Compliance Bedrock 11/7/2013
AB-13D Compliance Bedrock 3/5/2014
AB-13D Compliance Bedrock 7/7/2014
AB-13D Compliance Bedrock 11/4/2014
AB-13S Compliance Residuum 3/1/2011
AB-13S Compliance Residuum 7/7/2011
AB-13S Compliance Residuum 11/1/2011
AB-13S Compliance Residuum 3/5/2012
AB-13S Compliance Residuum 7/5/2012
AB-13S Compliance Residuum 11/5/2012
AB-13S Compliance Residuum 3/4/2013
AB-13S Compliance Residuum 7/1/2013
AB-13S Compliance Residuum 11/7/2013
AB-13S Compliance Residuum 3/5/2014
AB-13S Compliance Residuum 7/7/2014
AB-13S Compliance Residuum 11/4/2014
AB-14D Compliance Bedrock 3/1/2011
AB-14D Compliance Bedrock 7/21/2011
AB-14D Compliance Bedrock 11/1/2011
AB-14D Compliance Bedrock 3/5/2012
AB-14D Compliance Bedrock 7/5/2012
AB-14D Compliance Bedrock 11/5/2012
AB-14D Compliance Bedrock 3/5/2013
AB-14D Compliance Bedrock 7/2/2013
AB-14D Compliance Bedrock 11/7/2013
AB-14D Compliance Bedrock 3/5/2014
AB-14D Compliance Bedrock 7/7/2014
AB-14D Compliance Bedrock 11/4/2014
AB-1R Compliance Transition (Saprolite)3/1/2011
AB-1R Compliance Transition (Saprolite)7/7/2011
AB-1R Compliance Transition (Saprolite)11/1/2011
AB-1R Compliance Transition (Saprolite)3/5/2012
AB-1R Compliance Transition (Saprolite)7/5/2012
AB-1R Compliance Transition (Saprolite)11/5/2012
AB-1R Compliance Transition (Saprolite)3/4/2013
AB-1R Compliance Transition (Saprolite)7/1/2013
AB-1R Compliance Transition (Saprolite)11/7/2013
AB-1R Compliance Transition (Saprolite)3/5/2014
AB-1R Compliance Transition (Saprolite)7/7/2014
AB-1R Compliance Transition (Saprolite)11/4/2014
AB-2 Voluntary Transition (Saprolite)11/2/2004
Nitrate as N Strontium Sulfate TDS TOC TOX TSS
mg-N/L mg/L mg/L mg/L mg/L µg/L mg/L
10 NE 250 500 NE NE NE
300.0 300.0 2540C 5310B 2450D
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Total Total Total Dissolved Total Total Total Total Dissolved Total
200.7 200.7
1100NE
200.8 200.7 200.8 200.7
20 NE 0.2*
µg/L mg/L ug/L mg/Lµg/L mg/L
Selenium Sodium Thallium ZincNickelPotassium
N/A <5 0.04 N/A N/A N/A <1 N/A N/A N/A 0.22 33 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A N/A N/A <1 N/A N/A N/A 0.14 32 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.04 N/A N/A N/A <1 N/A N/A N/A 0.21 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A 0.83 N/A <1 N/A 2.26 N/A 0.21 20 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.1 N/A 0.706 N/A <1 N/A 2.2 N/A 0.27 18 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 0.05 0.749 0.804 <1 <1 2.29 2.32 N/A 0.15 <25 <0.2 <0.2 N/A N/A 6 0.006 0.006
N/A <5 0.09 N/A 0.872 N/A <1 N/A 2.38 N/A 0.13 <25 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.07 N/A 0.813 N/A <1 N/A 2.38 N/A 0.16 <25 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.04 N/A 0.878 N/A <1 N/A 2.32 N/A <0.1 <25 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 6 1 N/A N/A N/A <1 N/A N/A N/A 0.67 140 N/A <0.2 N/A N/A N/A N/A 0.005
N/A <5 2 N/A N/A N/A <1 N/A N/A N/A 1.3 160 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1 N/A N/A N/A <1 N/A N/A N/A 0.63 140 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.2 N/A N/A N/A <1 N/A N/A N/A 0.64 130 N/A <0.2 N/A N/A N/A N/A 0.006
N/A 6 0.93 N/A N/A N/A <1 N/A N/A N/A 0.57 <250 N/A <0.2 N/A N/A N/A N/A 0.007
N/A 8 0.72 N/A 3.39 N/A <1 N/A 8.07 N/A 0.45 120 N/A <0.2 N/A N/A N/A N/A 0.011
N/A <5 1.3 N/A 1.85 N/A <1 N/A 8.8 N/A 0.71 130 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 1.7 1.76 1.93 <1 <1 9.43 9.39 N/A 0.91 140 <0.2 <0.2 N/A N/A 5 <0.005 <0.005
N/A <5 0.78 N/A 1.82 N/A <1 N/A 8.92 N/A 0.39 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 2.2 N/A 1.82 N/A <1 N/A 9.36 N/A 0.92 140 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 2.4 N/A 1.8 N/A <1 N/A 9.56 N/A 0.91 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A <5 1.6 N/A N/A N/A <1 N/A N/A N/A 2.3 74 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.8 N/A N/A N/A <1 N/A N/A N/A 0.79 78 N/A <0.2 N/A N/A N/A N/A 0.005
N/A <5 1.7 N/A N/A N/A <1 N/A N/A N/A 0.26 67 N/A <0.2 N/A N/A N/A N/A 0.006
N/A <5 1.8 N/A N/A N/A <1 N/A N/A N/A 0.88 74 N/A <0.2 N/A N/A N/A N/A 0.006
N/A <5 1.9 N/A N/A N/A <1 N/A N/A N/A 0.41 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.6 N/A 0.73 N/A <1 N/A 4.26 N/A 0.18 56 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.5 N/A 2.76 N/A <1 N/A 6.44 N/A 3.8 85 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 1.7 0.827 0.911 <1 <1 4.63 4.68 N/A 0.44 68 <0.2 <0.2 N/A N/A 11 0.009 0.012
N/A <5 1.8 N/A 0.768 N/A <1 N/A 4.72 N/A 0.19 60 N/A <0.2 N/A N/A N/A N/A 0.008
N/A <5 1.7 N/A 1.78 N/A <1 N/A 5.6 N/A 1.6 84 N/A <0.2 N/A N/A N/A N/A 0.009
N/A <5 2.1 N/A 0.892 N/A <1 N/A 4.86 N/A 0.37 69 N/A <0.2 N/A N/A N/A N/A 0.008
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A 160 2.3 N/A N/A N/A <1 N/A N/A N/A 13 110 N/A <0.2 N/A N/A N/A N/A 0.007
N/A 460 3.3 N/A N/A N/A <1 N/A N/A N/A 17 110 N/A <0.2 N/A N/A N/A N/A 0.011
N/A 544 2.4 N/A N/A N/A <1 N/A N/A N/A 20 130 N/A <0.2 N/A N/A N/A N/A 0.01
N/A 214 2.3 N/A N/A N/A <1 N/A N/A N/A 28 119 N/A <0.2 N/A N/A N/A N/A 0.008
N/A 190 3.1 N/A N/A N/A <1 N/A N/A N/A 18 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A 180 2.4 N/A 1.75 N/A <1 N/A 16.6 N/A 21 100 N/A <0.2 N/A N/A N/A N/A 0.005
N/A 121 2.1 N/A 1.59 N/A <1 N/A 18 N/A 27 100 N/A <0.2 N/A N/A N/A N/A 0.006
117 104 2.4 1.59 1.62 <1 <1 17.8 17.9 N/A 22 110 <0.2 <0.2 N/A N/A <5 0.007 0.008
N/A 115 3 N/A 1.71 N/A <1 N/A 15.6 N/A 16 150 N/A <0.2 N/A N/A N/A N/A 0.006
N/A 90 2.4 N/A 1.64 N/A <1 N/A 19.3 N/A 24 110 N/A <0.2 N/A N/A N/A N/A 0.006
N/A 89 2.8 N/A 1.52 N/A <1 N/A 16.4 N/A 17 100 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A <5 <0.1 N/A N/A N/A <1 N/A N/A N/A 22 140 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.11 N/A N/A N/A <1 N/A N/A N/A 18 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.07 N/A N/A N/A <1 N/A N/A N/A 14 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.07 N/A N/A N/A <1 N/A N/A N/A 11 111 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.07 N/A N/A N/A <1 N/A N/A N/A 12 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A 2.04 N/A <1 N/A 5.95 N/A 9 94 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A 1.83 N/A <1 N/A 5.47 N/A 6.1 93 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 0.05 1.74 1.67 <1 <1 5.74 5.65 N/A 7.4 97 <0.2 <0.2 N/A N/A <5.2 <0.005 <0.005
N/A <5 0.06 N/A 1.72 N/A <1 N/A 5.72 N/A 9.4 100 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.08 N/A 1.81 N/A <1 N/A 5.99 N/A 14 100 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.22 N/A 2.49 N/A 1.9 N/A 7.58 N/A 56 170 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 0.11 N/A 1.58 N/A <2 N/A 3.683 N/A 3.2 <20 N/A N/A 0.74 <10 N/A N/A <0.02
Tables - Page 17
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
AB-2 Voluntary Transition (Saprolite)5/2/2005
AB-2 Voluntary Transition (Saprolite)11/16/2005
AB-2 Voluntary Transition (Saprolite)5/8/2006
AB-2 Voluntary Transition (Saprolite)11/13/2006
AB-2 Voluntary Transition (Saprolite)5/14/2007
AB-2 Voluntary Transition (Saprolite)11/7/2007
AB-2 Voluntary Transition (Saprolite)5/14/2008
AB-2 Voluntary Transition (Saprolite)11/3/2008
AB-2 Voluntary Transition (Saprolite)5/13/2009
AB-2 Voluntary Transition (Saprolite)11/3/2009
AB-2 Voluntary Transition (Saprolite)5/4/2010
AB-2 Voluntary Transition (Saprolite)3/1/2011
AB-2D Voluntary Partially Weathered Rock 11/2/2004
AB-2D Voluntary Partially Weathered Rock 5/2/2005
AB-2D Voluntary Partially Weathered Rock 11/16/2005
AB-2D Voluntary Partially Weathered Rock 5/8/2006
AB-2D Voluntary Partially Weathered Rock 11/13/2006
AB-2D Voluntary Partially Weathered Rock 5/14/2007
AB-2D Voluntary Partially Weathered Rock 11/7/2007
AB-2D Voluntary Partially Weathered Rock 5/14/2008
AB-2D Voluntary Partially Weathered Rock 11/3/2008
AB-2D Voluntary Partially Weathered Rock 5/13/2009
AB-2D Voluntary Partially Weathered Rock 11/3/2009
AB-2D Voluntary Partially Weathered Rock 5/4/2010
AB-2D Voluntary Partially Weathered Rock 3/1/2011
AB-4D Compliance Partially Weathered Rock 11/2/2004
AB-4D Compliance Partially Weathered Rock 5/2/2005
AB-4D Compliance Partially Weathered Rock 11/16/2005
AB-4D Compliance Partially Weathered Rock 5/8/2006
AB-4D Compliance Partially Weathered Rock 11/13/2006
AB-4D Compliance Partially Weathered Rock 5/14/2007
AB-4D Compliance Partially Weathered Rock 11/7/2007
AB-4D Compliance Partially Weathered Rock 5/14/2008
AB-4D Compliance Partially Weathered Rock 11/3/2008
AB-4D Compliance Partially Weathered Rock 5/13/2009
AB-4D Compliance Partially Weathered Rock 11/3/2009
AB-4D Compliance Partially Weathered Rock 5/4/2010
AB-4D Compliance Partially Weathered Rock 3/1/2011
AB-4D Compliance Partially Weathered Rock 7/7/2011
AB-4D Compliance Partially Weathered Rock 11/1/2011
AB-4D Compliance Partially Weathered Rock 3/5/2012
AB-4D Compliance Partially Weathered Rock 7/5/2012
AB-4D Compliance Partially Weathered Rock 11/5/2012
AB-4D Compliance Partially Weathered Rock 3/5/2013
AB-4D Compliance Partially Weathered Rock 7/2/2013
AB-4D Compliance Partially Weathered Rock 11/6/2013
AB-4D Compliance Partially Weathered Rock 3/5/2014
AB-4D Compliance Partially Weathered Rock 7/7/2014
AB-4D Compliance Partially Weathered Rock 11/4/2014
AB-4S (4)Compliance Transition (Saprolite)11/2/2004
AB-4S (4)Compliance Transition (Saprolite)5/2/2005
AB-4S (4)Compliance Transition (Saprolite)11/16/2005
AB-4S (4)Compliance Transition (Saprolite)5/8/2006
AB-4S (4)Compliance Transition (Saprolite)11/13/2006
AB-4S (4)Compliance Transition (Saprolite)5/14/2007
AB-4S (4)Compliance Transition (Saprolite)11/7/2007
AB-4S (4)Compliance Transition (Saprolite)5/14/2008
AB-4S (4)Compliance Transition (Saprolite)11/3/2008
AB-4S (4)Compliance Transition (Saprolite)5/13/2009
Nitrate as N Strontium Sulfate TDS TOC TOX TSS
mg-N/L mg/L mg/L mg/L mg/L µg/L mg/L
10 NE 250 500 NE NE NE
300.0 300.0 2540C 5310B 2450D
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Total Total Total Dissolved Total Total Total Total Dissolved Total
200.7 200.7
1100NE
200.8 200.7 200.8 200.7
20 NE 0.2*
µg/L mg/L ug/L mg/Lµg/L mg/L
Selenium Sodium Thallium ZincNickelPotassium
N/A N/A <0.02 N/A N/A N/A <2 N/A N/A N/A 7 22 N/A N/A 0.34 <20 N/A N/A <0.02
N/A N/A 0.03 N/A 1.7 N/A <2 N/A 2.183 N/A 1.57 <20 N/A N/A 0.21 27.3 N/A N/A 0.007
N/A <2 0.02 N/A 1.61 N/A <2 N/A 2.035 N/A 1.49 20 N/A N/A 0.24 <1000 N/A N/A <0.005
N/A <2 <0.02 N/A 1.62 N/A <2 N/A 2.279 N/A 0.64 20 N/A N/A 0.16 <1000 N/A N/A 0.007
N/A <2 <0.02 N/A 1.62 N/A <2 N/A 2.11 N/A 0.43 <10 N/A N/A 0.2 <1000 N/A N/A 0.006
N/A <2 <0.02 N/A 1.64 N/A <2 N/A 2.008 N/A 0.53 29 N/A N/A 0.15 <1000 N/A N/A <0.005
N/A <2 <0.02 N/A 1.55 N/A <2 N/A 1.98 N/A 0.49 16 N/A N/A 0.115 <20 N/A N/A 0.006
N/A <2 <0.02 N/A 1.21 N/A <2 N/A 5.25 N/A 1.9 188 N/A N/A 0.745 40 N/A N/A <0.005
N/A <1 <0.02 N/A 1.28 N/A <1 N/A 3.92 N/A 0.95 40 N/A N/A 0.288 <20 N/A N/A 0.005
N/A <1 0.02 N/A 1.54 N/A <1 N/A 3.09 N/A 1 22 N/A N/A 0.25 <50 N/A N/A <0.005
N/A <1 <0.02 N/A 1.51 N/A <1 N/A 2.7 N/A 0.8 32 N/A N/A 0.174 <100 N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 0.34 N/A 1.29 N/A <2 N/A 6.567 N/A 0.41 60 N/A N/A 0.18 <10 N/A N/A <0.02
N/A N/A 0.16 N/A N/A N/A <2 N/A N/A N/A 0.34 84 N/A N/A 0.17 <20 N/A N/A <0.02
N/A N/A 0.32 N/A 1.15 N/A <2 N/A 7.267 N/A 0.5 80 N/A N/A <0.1 <10 N/A N/A <0.005
N/A <2 0.25 N/A 1.17 N/A <2 N/A 6.452 N/A 0.2 82 N/A N/A 0.16 <1000 N/A N/A <0.005
N/A <2 0.33 N/A 1.1 N/A <2 N/A 7.427 N/A 0.55 84 N/A N/A 0.11 <1000 N/A N/A <0.005
N/A <2 0.26 N/A 1.1 N/A <2 N/A 6.745 N/A 0.19 58 N/A N/A 0.11 <1000 N/A N/A <0.005
N/A <2 0.35 N/A 1.15 N/A <2 N/A 6.662 N/A 0.6 103 N/A N/A 0.11 <1000 N/A N/A <0.005
N/A <2 0.25 N/A 1.07 N/A <2 N/A 5.99 N/A 0.26 91 N/A N/A <0.1 <20 N/A N/A <0.005
N/A <2 0.34 N/A 1.13 N/A <2 N/A 6.9 N/A 0.64 122 N/A N/A 0.122 <20 N/A N/A <0.005
N/A <1 0.19 N/A 1.14 N/A <1 N/A 5.95 N/A 0.26 84 N/A N/A <0.1 <20 N/A N/A <0.005
N/A <1 0.34 N/A 1.14 N/A <1 N/A 7.23 N/A 0.64 102 N/A N/A <0.1 <50 N/A N/A <0.005
N/A <2 0.21 N/A 1.11 N/A <1 N/A 5.94 N/A 0.22 90 N/A N/A <0.1 <100 N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 1.8 N/A 1.64 N/A <2 N/A 6.734 N/A 4.6 80 N/A N/A 0.68 <10 N/A N/A 0.026
N/A N/A 1.9 N/A N/A N/A <2 N/A N/A N/A 6.8 110 N/A N/A 0.21 <20 N/A N/A 0.12
N/A N/A 1.74 N/A 1.28 N/A <2 N/A 6.863 N/A 3.62 80 N/A N/A 0.14 <10 N/A N/A 0.107
N/A 34.79 1.89 N/A 1.32 N/A <2 N/A 6.786 N/A 4.48 94 N/A N/A 0.21 <1000 N/A N/A 0.091
N/A 27.2 1.78 N/A 1.41 N/A <2 N/A 7.199 N/A 4.37 94 N/A N/A 0.22 <1000 N/A N/A 0.086
N/A 16.74 1.65 N/A 1.36 N/A <2 N/A 7.232 N/A 4.31 70 N/A N/A 0.18 <1000 N/A N/A 0.056
N/A 18.5 1.68 N/A 1.33 N/A <2 N/A 6.526 N/A 2.7 111 N/A N/A 0.18 <1000 N/A N/A 0.056
N/A 12.4 1.78 N/A 1.27 N/A <2 N/A 6.36 N/A 3.7 110 N/A N/A <0.1 <20 N/A N/A 0.042
N/A 15.2 1.73 N/A 1.34 N/A <2 N/A 6.72 N/A 3 114 N/A N/A 0.167 40 N/A N/A 0.045
N/A 11 1.72 N/A 1.35 N/A <1 N/A 6.64 N/A 3.9 96 N/A N/A 0.126 <20 N/A N/A 0.036
N/A 9.6 1.65 N/A 1.33 N/A <1 N/A 7.41 N/A 3.3 110 N/A N/A 0.169 <50 N/A N/A 0.032
N/A 8.1 1.64 N/A 1.31 N/A <1 N/A 6.94 N/A 5.1 112 N/A N/A <0.1 <100 N/A N/A 0.026
N/A 8 1.8 N/A N/A N/A <1 N/A N/A N/A 2.8 93 N/A <0.2 N/A N/A N/A N/A 0.023
N/A 7 1.8 N/A N/A N/A <1 N/A N/A N/A 4.6 120 N/A <0.2 N/A N/A N/A N/A 0.019
N/A 7 1.8 N/A N/A N/A <1 N/A N/A N/A 3.4 120 N/A <0.2 N/A N/A N/A N/A 0.02
N/A 7 2 N/A N/A N/A <1 N/A N/A N/A 3 93 N/A <0.2 N/A N/A N/A N/A 0.019
N/A 6 1.9 N/A N/A N/A <1 N/A N/A N/A 4.3 <250 N/A <0.2 N/A N/A N/A N/A 0.017
N/A 8 1.9 N/A 1.39 N/A <1 N/A 6.88 N/A 3.3 100 N/A <0.2 N/A N/A N/A N/A 0.019
N/A 7 2.2 N/A 1.41 N/A <1 N/A 6.94 N/A 2.5 110 N/A <0.2 N/A N/A N/A N/A 0.021
7 7 1.9 1.42 1.41 <1 <1 7.02 6.95 N/A 3.8 100 <0.2 <0.2 N/A N/A <5 0.021 0.022
N/A 7 2 N/A 1.57 N/A <1 N/A 7.99 N/A 4.5 110 N/A <0.2 N/A N/A N/A N/A 0.02
N/A 6 2.1 N/A 1.38 N/A <1 N/A 6.75 N/A 3.3 110 N/A <0.2 N/A N/A N/A N/A 0.018
N/A 5 2 N/A 1.45 N/A <1 N/A 7.91 N/A 4.9 110 N/A <0.2 N/A N/A N/A N/A 0.014
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 1.1 N/A 1.26 N/A <2 N/A 6.859 N/A 4.1 68 N/A N/A 0.75 11 N/A N/A <0.02
N/A N/A 5.1 N/A N/A N/A <2 N/A N/A N/A 15 100 N/A N/A 0.7 <20 N/A N/A <0.02
N/A N/A 1.94 N/A 1.98 N/A <2 N/A 7.071 N/A 5.15 76 N/A N/A 0.58 <10 N/A N/A 0.007
N/A <2 2.29 N/A 3.22 N/A <2 N/A 7.997 N/A 8.32 76 N/A N/A 0.77 <1000 N/A N/A <0.005
N/A <2 2.33 N/A 5.52 N/A <2 N/A 8.33 N/A 13.91 96 N/A N/A 2.26 <1000 N/A N/A 0.006
N/A <2 2.74 N/A 5.27 N/A <2 N/A 7.812 N/A 10.6 76 N/A N/A 1.74 <1000 N/A N/A <0.005
N/A <2 4.98 N/A 4.38 N/A <2 N/A 7.301 N/A 5.9 118 N/A N/A 1.07 <1000 N/A N/A <0.005
N/A <2 2.93 N/A 5.18 N/A <2 N/A 6.65 N/A 13 100 N/A N/A 2.3 <20 N/A N/A <0.005
N/A <2 4.29 N/A 4.47 N/A <2 N/A 9.16 N/A 13 128 N/A N/A 2.28 50 N/A N/A <0.005
N/A <1 1.15 N/A 5.02 N/A <1 N/A 7.35 N/A 14 88 N/A N/A 1.79 <20 N/A N/A <0.005
Tables - Page 18
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
AB-4S (4)Compliance Transition (Saprolite)11/3/2009
AB-4S (4)Compliance Transition (Saprolite)5/4/2010
AB-4S (4)Compliance Transition (Saprolite)3/1/2011
AB-4S (4)Compliance Transition (Saprolite)7/7/2011
AB-4S (4)Compliance Transition (Saprolite)11/1/2011
AB-4S (4)Compliance Transition (Saprolite)3/5/2012
AB-4S (4)Compliance Transition (Saprolite)7/5/2012
AB-4S (4)Compliance Transition (Saprolite)11/5/2012
AB-4S (4)Compliance Transition (Saprolite)3/5/2013
AB-4S (4)Compliance Transition (Saprolite)7/2/2013
AB-4S (4)Compliance Transition (Saprolite)11/6/2013
AB-4S (4)Compliance Transition (Saprolite)3/5/2014
AB-4S (4)Compliance Transition (Saprolite)7/7/2014
AB-4S (4)Compliance Transition (Saprolite)11/4/2014
AB-5 Voluntary Transition (Saprolite)11/2/2004
AB-5 Voluntary Transition (Saprolite)5/2/2005
AB-5 Voluntary Transition (Saprolite)11/16/2005
AB-5 Voluntary Transition (Saprolite)5/8/2006
AB-5 Voluntary Transition (Saprolite)11/13/2006
AB-5 Voluntary Transition (Saprolite)5/14/2007
AB-5 Voluntary Transition (Saprolite)11/7/2007
AB-5 Voluntary Transition (Saprolite)5/14/2008
AB-5 Voluntary Transition (Saprolite)11/3/2008
AB-5 Voluntary Transition (Saprolite)5/13/2009
AB-5 Voluntary Transition (Saprolite)11/3/2009
AB-5 Voluntary Transition (Saprolite)5/4/2010
AB-5 Voluntary Transition (Saprolite)3/1/2011
AB-5 Voluntary Transition (Saprolite)7/7/2011
AB-5 Voluntary Transition (Saprolite)11/1/2011
AB-6A Voluntary Alluvium 3/21/2005
AB-6A Voluntary Alluvium 5/2/2005
AB-6A Voluntary Alluvium 11/16/2005
AB-6A Voluntary Alluvium 5/8/2006
AB-6A Voluntary Alluvium 11/13/2006
AB-6A Voluntary Alluvium 5/14/2007
AB-6A Voluntary Alluvium 11/7/2007
AB-6A Voluntary Alluvium 5/14/2008
AB-6A Voluntary Alluvium 11/3/2008
AB-6A Voluntary Alluvium 5/13/2009
AB-6A Voluntary Alluvium 11/3/2009
AB-6A Voluntary Alluvium 5/4/2010
AB-6A Voluntary Alluvium 3/1/2011
AB-6A Voluntary Alluvium 7/7/2011
AB-6A Voluntary Alluvium 11/1/2011
AB-6R Voluntary Transition (Saprolite)3/21/2005
AB-6R Voluntary Transition (Saprolite)5/2/2005
AB-6R Voluntary Transition (Saprolite)11/16/2005
AB-6R Voluntary Transition (Saprolite)5/8/2006
AB-6R Voluntary Transition (Saprolite)11/13/2006
AB-6R Voluntary Transition (Saprolite)5/14/2007
AB-6R Voluntary Transition (Saprolite)11/7/2007
AB-6R Voluntary Transition (Saprolite)5/14/2008
AB-6R Voluntary Transition (Saprolite)11/3/2008
AB-6R Voluntary Transition (Saprolite)5/13/2009
AB-6R Voluntary Transition (Saprolite)11/3/2009
AB-6R Voluntary Transition (Saprolite)5/4/2010
AB-6R Voluntary Transition (Saprolite)3/1/2011
AB-6R Voluntary Transition (Saprolite)7/7/2011
AB-6R Voluntary Transition (Saprolite)11/1/2011
Nitrate as N Strontium Sulfate TDS TOC TOX TSS
mg-N/L mg/L mg/L mg/L mg/L µg/L mg/L
10 NE 250 500 NE NE NE
300.0 300.0 2540C 5310B 2450D
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Total Total Total Dissolved Total Total Total Total Dissolved Total
200.7 200.7
1100NE
200.8 200.7 200.8 200.7
20 NE 0.2*
µg/L mg/L ug/L mg/Lµg/L mg/L
Selenium Sodium Thallium ZincNickelPotassium
N/A <1 3.36 N/A 4.81 N/A <1 N/A 7.85 N/A 14 102 N/A N/A 3.45 <50 N/A N/A <0.005
N/A <2 1.28 N/A 4.27 N/A <1 N/A 6.01 N/A 13 94 N/A N/A 1.45 <100 N/A N/A <0.005
N/A <5 3.5 N/A N/A N/A <1 N/A N/A N/A 9.7 86 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.92 N/A N/A N/A <1 N/A N/A N/A 11 87 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.9 N/A N/A N/A <1 N/A N/A N/A 12 110 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 2.6 N/A N/A N/A <1 N/A N/A N/A 16 92 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.52 N/A N/A N/A <1 N/A N/A N/A 9.2 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.97 N/A 4.28 N/A <1 N/A 7.75 N/A 9.8 80 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 1.9 N/A 4.47 N/A <1 N/A 5.83 N/A 13 91 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 0.11 6.32 6.42 <1 <1 5.2 5.3 N/A 12 99 <0.2 <0.2 N/A N/A 8 <0.005 0.005
N/A <5 3.5 N/A 4.97 N/A <1 N/A 6.95 N/A 11 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 2.5 N/A 5.01 N/A <1 N/A 5.32 N/A 13 84 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.51 N/A 5 N/A <1 N/A 4.93 N/A 11 83 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 0.14 N/A 1.62 N/A <2 N/A 3.433 N/A 2.6 22 N/A N/A 0.74 <10 N/A N/A <0.02
N/A N/A 0.05 N/A N/A N/A <2 N/A N/A N/A 8.2 44 N/A N/A 0.25 <20 N/A N/A <0.02
N/A N/A 0.04 N/A 1.04 N/A <2 N/A 2.806 N/A 1.59 22 N/A N/A 0.16 20.3 N/A N/A 0.012
N/A <2 0.04 N/A 1.03 N/A <2 N/A 2.624 N/A 1.42 38 N/A N/A 0.16 <1000 N/A N/A 0.009
N/A <2 0.03 N/A 1.07 N/A <2 N/A 2.694 N/A 1.16 34 N/A N/A 0.16 <1000 N/A N/A 0.01
N/A <2 <0.02 N/A 1.1 N/A <2 N/A 2.653 N/A 1.07 <10 N/A N/A 0.16 <1000 N/A N/A 0.009
N/A 2.06 0.03 N/A 2.73 N/A <2 N/A 2.43 N/A 1.18 50 N/A N/A 0.25 <1000 N/A N/A 0.027
N/A <2 0.05 N/A 1.28 N/A <2 N/A 2.47 N/A 1.3 33 N/A N/A 0.194 <20 N/A N/A 0.007
N/A <2 <0.02 N/A 1.29 N/A <2 N/A 2.47 N/A 1.2 202 N/A N/A 2.43 20 N/A N/A 0.007
N/A <1 0.03 N/A 1.03 N/A <1 N/A 2.52 N/A 1.4 30 N/A N/A 0.534 <20 N/A N/A 0.009
N/A <1 <0.02 N/A 0.997 N/A <1 N/A 2.57 N/A 1.2 36 N/A N/A 0.13 <50 N/A N/A <0.005
N/A <2 <0.02 N/A 1.19 N/A <1 N/A 2.4 N/A 1.2 <100 N/A N/A 0.142 <100 N/A N/A 0.008
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 0.08 N/A 0.78 N/A <2 N/A 8.304 N/A 19.8 100 N/A N/A 0.31 <20 N/A N/A <0.02
N/A N/A 0.06 N/A N/A N/A <2 N/A N/A N/A 19 120 N/A N/A 0.32 <20 N/A N/A <0.02
N/A N/A 0.07 N/A 0.76 N/A <2 N/A 8.735 N/A 19.9 100 N/A N/A 0.18 40.8 N/A N/A <0.005
N/A <2 0.08 N/A 0.77 N/A <2 N/A 8.529 N/A 20.89 120 N/A N/A 0.22 <1000 N/A N/A <0.005
N/A <2 0.07 N/A 0.68 N/A <2 N/A 9.023 N/A 22.7 120 N/A N/A 0.19 <1000 N/A N/A <0.005
N/A <2 0.07 N/A 0.8 N/A <2 N/A 8.86 N/A 20.19 74 N/A N/A 0.21 <1000 N/A N/A <0.005
N/A <2 0.08 N/A 0.78 N/A <2 N/A 8.445 N/A 23.49 111 N/A N/A 0.25 <1000 N/A N/A <0.005
N/A <2 0.08 N/A 0.72 N/A <2 N/A 8.64 N/A 24 110 N/A N/A 0.101 20 N/A N/A <0.005
N/A <2 0.07 N/A 0.83 N/A <2 N/A 8.79 N/A 26 214 N/A N/A 0.225 30 N/A N/A <0.005
N/A <1 0.05 N/A 0.82 N/A <1 N/A 9.07 N/A 24 124 N/A N/A 0.197 <20 N/A N/A <0.005
N/A <1 0.06 N/A 0.924 N/A <1 N/A 9.5 N/A 25 118 N/A N/A 0.171 <50 N/A N/A <0.005
N/A <1 0.05 N/A 0.857 N/A <1 N/A 9.12 N/A 26 114 N/A N/A 0.113 <100 N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A 0.09 N/A 1.6 N/A <2 N/A 9.215 N/A 16.2 97 N/A N/A 0.33 <20 N/A N/A 0.024
N/A N/A 0.08 N/A N/A N/A <2 N/A N/A N/A 15 120 N/A N/A 0.23 <20 N/A N/A <0.02
N/A N/A 0.11 N/A 1.67 N/A <2 N/A 8.884 N/A 15.8 110 N/A N/A 0.16 49.2 N/A N/A 0.01
N/A <2 0.06 N/A 1.47 N/A <2 N/A 8.805 N/A 17.88 110 N/A N/A 0.2 <1000 N/A N/A <0.005
N/A 2 0.04 N/A 1.43 N/A <2 N/A 9.169 N/A 19.73 96 N/A N/A 0.16 <1000 N/A N/A <0.005
N/A <2 0.06 N/A 1.41 N/A <2 N/A 8.654 N/A 17.74 72 N/A N/A 0.17 <1000 N/A N/A <0.005
N/A 2.7 0.07 N/A 1.64 N/A <2 N/A 8.074 N/A 20.36 120 N/A N/A 0.16 <1000 N/A N/A 0.006
N/A <2 0.05 N/A 1.41 N/A <2 N/A 8.29 N/A 20 95 N/A N/A <0.1 <20 N/A N/A <0.005
N/A <2 0.06 N/A 1.43 N/A <2 N/A 8.66 N/A 21 146 N/A N/A 0.208 <20 N/A N/A <0.005
N/A <1 0.07 N/A 1.42 N/A <1 N/A 8.77 N/A 20 114 N/A N/A 0.147 <20 N/A N/A <0.005
N/A <1 0.08 N/A 1.41 N/A <1 N/A 9.1 N/A 24 118 N/A N/A 0.133 <50 N/A N/A <0.005
N/A 1.4 0.05 N/A 1.42 N/A <1 N/A 8.44 N/A 22 120 N/A N/A <0.1 <100 N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tables - Page 19
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Analytical Method
Well Name Well Type Hydrostratigraphic Unit Sample Collection Date
15A NCAC 02L .0202(g) Groundwater Quality Standard
Analytical Parameter
Units
AB-8 Voluntary Transition (Saprolite)3/21/2005
AB-8 Voluntary Transition (Saprolite)5/2/2005
AB-8 Voluntary Transition (Saprolite)11/16/2005
AB-8 Voluntary Transition (Saprolite)5/8/2006
AB-8 Voluntary Transition (Saprolite)11/13/2006
AB-8 Voluntary Transition (Saprolite)5/14/2007
AB-8 Voluntary Transition (Saprolite)11/7/2007
AB-8 Voluntary Transition (Saprolite)5/14/2008
AB-8 Voluntary Transition (Saprolite)11/3/2008
AB-8 Voluntary Transition (Saprolite)5/13/2009
AB-8 Voluntary Transition (Saprolite)11/3/2009
AB-8 Voluntary Transition (Saprolite)5/4/2010
AB-9D Compliance Bedrock 3/1/2011
AB-9D Compliance Bedrock 7/7/2011
AB-9D Compliance Bedrock 11/1/2011
AB-9D Compliance Bedrock 3/5/2012
AB-9D Compliance Bedrock 7/5/2012
AB-9D Compliance Bedrock 11/5/2012
AB-9D Compliance Bedrock 3/4/2013
AB-9D Compliance Bedrock 7/1/2013
AB-9D Compliance Bedrock 11/6/2013
AB-9D Compliance Bedrock 3/5/2014
AB-9D Compliance Bedrock 7/7/2014
AB-9D Compliance Bedrock 11/4/2014
AB-9S Compliance Transition (Saprolite)3/1/2011
AB-9S Compliance Transition (Saprolite)7/7/2011
AB-9S Compliance Transition (Saprolite)11/1/2011
AB-9S Compliance Transition (Saprolite)3/5/2012
AB-9S Compliance Transition (Saprolite)7/5/2012
AB-9S Compliance Transition (Saprolite)11/5/2012
AB-9S Compliance Transition (Saprolite)3/4/2013
AB-9S Compliance Transition (Saprolite)7/1/2013
AB-9S Compliance Transition (Saprolite)11/6/2013
AB-9S Compliance Transition (Saprolite)3/5/2014
AB-9S Compliance Transition (Saprolite)7/7/2014
AB-9S Compliance Transition (Saprolite)11/4/2014
Nitrate as N Strontium Sulfate TDS TOC TOX TSS
mg-N/L mg/L mg/L mg/L mg/L µg/L mg/L
10 NE 250 500 NE NE NE
300.0 300.0 2540C 5310B 2450D
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Total Total Total Dissolved Total Total Total Total Dissolved Total
200.7 200.7
1100NE
200.8 200.7 200.8 200.7
20 NE 0.2*
µg/L mg/L ug/L mg/Lµg/L mg/L
Selenium Sodium Thallium ZincNickelPotassium
N/A N/A 0.19 N/A 2.54 N/A <2 N/A 10.781 N/A 32.5 120 N/A N/A 0.28 <20 N/A N/A <0.02
N/A N/A <0.02 N/A N/A N/A <2 N/A N/A N/A 23 150 N/A N/A 0.22 <20 N/A N/A <0.02
N/A N/A 0.14 N/A 2.42 N/A <2 N/A 10.824 N/A 22.4 130 N/A N/A 0.21 27.2 N/A N/A <0.005
N/A <2 0.15 N/A 2.41 N/A <2 N/A 10.348 N/A 22.98 140 N/A N/A 0.22 <1000 N/A N/A <0.005
N/A <2 0.13 N/A 2.48 N/A <2 N/A 11.071 N/A 24.91 130 N/A N/A 0.15 <1000 N/A N/A <0.005
N/A <2 0.13 N/A 2.62 N/A <2 N/A 10.925 N/A 23.86 102 N/A N/A 0.19 <1000 N/A N/A <0.005
N/A <2 0.14 N/A 2.43 N/A <2 N/A 9.848 N/A 27.96 147 N/A N/A 0.18 <1000 N/A N/A <0.005
N/A <2 0.14 N/A 2.41 N/A <2 N/A 10 N/A 28 130 N/A N/A <0.1 40 N/A N/A <0.005
N/A <2 0.15 N/A 2.53 N/A <2 N/A 10.5 N/A 32 190 N/A N/A 0.197 40 N/A N/A <0.005
N/A <1 0.14 N/A 2.59 N/A <1 N/A 11 N/A 31 172 N/A N/A 0.166 <20 N/A N/A <0.005
N/A <1 0.16 N/A 2.57 N/A <1 N/A 11.1 N/A 31 150 N/A N/A 0.147 <50 N/A N/A <0.005
N/A <1 0.13 N/A 2.56 N/A <1 N/A 10.6 N/A 31 146 N/A N/A <0.1 <100 N/A N/A <0.005
N/A <5 <0.1 N/A N/A N/A 2.59 N/A N/A N/A 38 180 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A N/A N/A 2.82 N/A N/A N/A 40 200 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A N/A N/A 3.63 N/A N/A N/A 38 190 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A N/A N/A 3.8 N/A N/A N/A 39 204 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A N/A N/A 3.19 N/A N/A N/A 39 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A 2.28 N/A 3.27 N/A 11.1 N/A 39 180 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.06 N/A 2.17 N/A 3.82 N/A 11 N/A 38 190 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 0.05 2.24 2.3 3.07 3.16 11.4 11.4 N/A 40 190 <0.2 <0.2 N/A N/A <5 <0.005 <0.005
N/A <5 0.05 N/A 2.35 N/A 3.18 N/A 11.6 N/A 42 190 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A 2.29 N/A 2.93 N/A 11.5 N/A 42 200 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 0.05 N/A 2.22 N/A 2.82 N/A 11.4 N/A 41 190 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
N/A <5 <0.1 N/A N/A N/A <1 N/A N/A N/A 32 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 36 140 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 38 150 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.02 N/A N/A N/A <1 N/A N/A N/A 34 126 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A N/A N/A <1 N/A N/A N/A 37 <250 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.16 N/A <1 N/A 10.5 N/A 35 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.05 N/A <1 N/A 10.2 N/A 34 130 N/A <0.2 N/A N/A N/A N/A <0.005
<5 <5 <0.023 0.985 0.967 <1 <1 10.9 10.7 N/A 33 130 <0.2 <0.2 N/A N/A <5 <0.005 <0.005
N/A <5 <0.023 N/A 0.991 N/A <1 N/A 11 N/A 31 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 1.04 N/A <1 N/A 10.9 N/A 35 120 N/A <0.2 N/A N/A N/A N/A <0.005
N/A <5 <0.023 N/A 0.892 N/A <1 N/A 10.5 N/A 30 130 N/A <0.2 N/A N/A N/A N/A <0.005
N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Tables - Page 20
Table 7. Historical groundwater analytical results (compliance and voluntary monitoring wells)
Notes:
1.Depth to Water measured from the top of well casing.
2.Analytical parameter abreviations:
Temp. = Temperature
DO = Dissolved oxygen
Cond. = Specific conductivity
ORP = Oxidation reduction potential
TDS = Total dissolved solids
TSS = Total suspended solids
TOC = Total organic carbon
3.Units:
˚C = Degrees Celcius
SU = Standard Units
mV = millivolts
NTU = Nephelometric Turbidity Unit
mg/L = milligrams per liter
µg/L = micrograms per liter
µmhos/cm = micromhos per centimeter
CaCO3 = calcium carbonate
HCO3- = bicarbonate
CO32- = carbonate
4.N/A = Not applicable
5.NE = Not established
6.* Interim Maximum Allowable Concentration (IMAC) standards
7.Highlighted values indicate values that exceed the 15A NCAC 2L Standard
8.Analytical results with "<" preceding the result indicates that the parameter
was not detected at a concentration which attains or exceeds the laboratory reporting limit.
Tables - Page 21
Table 8. Historical surface water analytical results (ash basin)
Analytical Parameter Depth to Water Temp.DO Cond.pH ORP Turbidity Alkalinity Aluminum Beryllium
Units Feet ˚C mg/L µmhos/cm SU mV NTU mg/L CaCO3 µg/L µg/L
NA NA NA NA 6.0 - 9.0 NA NA NE 87 6.5
Analytical Method 2320B4d
Well Name Sample Collection Date Total Total Dissolved Total Dissolved Total Dissolved Total Total Dissolved Total Dissolved Total
Ash Basin-NE 7/1/2013 N/A 27.08 0 608 3.54 590 6.67 N/A N/A <1 <1 2.43 2.42 55 55 N/A 670 677 1.29 1.31
CIF 3/24/2010 N/A 17.31 N/A 75.2 6.68 N/A 25.4 N/A N/A N/A N/A N/A <1 N/A 24 N/A N/A <100 N/A <1
PH ADJ. BLDG.3/24/2010 N/A 17.67 N/A 152.6 6.58 N/A 8.71 N/A N/A N/A N/A N/A <1 N/A 52 N/A N/A <100 N/A <1
Tower-0.3m 7/1/2013 N/A 27.22 5.46 435 6.39 334 2.01 N/A N/A <1 <1 2.06 2.24 74 74 N/A 2090 2080 <1 <1
Antimony Arsenic Barium Boron Cadmium
µg/L µg/L µg/L µg/L µg/L
5.6 10 1000 NE 2
200.8 200.8 200.7 200.7 200.8
15A NCAC 02B .0200 Surface Water Quality Standard
Field Measurements
Tables - Page 22
Table 8. Historical surface water analytical results (ash basin)
Analytical Parameter
Units
Analytical Method
Well Name Sample Collection Date
Ash Basin-NE 7/1/2013
CIF 3/24/2010
PH ADJ. BLDG.3/24/2010
Tower-0.3m 7/1/2013
15A NCAC 02B .0200 Surface Water Quality Standard
Chloride
mg/L
230
300
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total Dissolved Total
27.5 27.6 9.6 <5 <5 N/A N/A 0.088 0.086 11600 11900 9.08 11.9 11.2 11.2 1450 1450 <0.05 <0.05 N/A N/A
N/A 5.75 2.5 N/A <1 N/A N/A N/A <0.001 N/A 79.5 N/A <1 N/A 1.36 N/A 5.29 N/A <0.05 N/A N/A
N/A 14.2 7.8 N/A 1.2 N/A N/A N/A <0.001 N/A <10 N/A <1 N/A 4.06 N/A <5 N/A <0.05 N/A N/A
48.8 48.2 75 <5 <5 N/A N/A <0.005 <0.005 17 146 <1 <1 13.4 13.3 112 114 <0.05 <0.05 N/A N/A
Chromium Cobalt Copper Iron Lead Magnesium Manganese Mercury MolydenumCalcium
µg/L µg/L mg/L µg/L µg/L µg/L µg/L µg/L µg/Lmg/L
NE 200 0.012 160NE5037100025
200.7 200.8 245.1 200.8200.7 200.7 200.8 200.7 200.7 200.8
Tables - Page 23
Table 8. Historical surface water analytical results (ash basin)
Analytical Parameter
Units
Analytical Method
Well Name Sample Collection Date
Ash Basin-NE 7/1/2013
CIF 3/24/2010
PH ADJ. BLDG.3/24/2010
Tower-0.3m 7/1/2013
15A NCAC 02B .0200 Surface Water Quality Standard
Nitrate as N Strontium Sulfate TDS TOC TOX TSS
mg-N/L mg/L mg/L mg/L mg/L µg/L mg/L
10 14 250 500 NE NE NE
300.0 300.0 2540C 5310B 2450D
Dissolved Total Total Dissolved Total Dissolved Total Dissolved Total Total Total Total Dissolved Total Total Total Total Dissolved Total
110 109 0.39 3.82 3.86 13 12.8 38.5 38.6 N/A 270 380 <0.2 <0.2 N/A N/A <5.56 0.549 0.578
N/A <1 0.62 N/A 1.87 N/A <1 N/A 6.16 N/A 0.56 212 N/A N/A <0.1 N/A N/A N/A 0.006
N/A <1 <0.02 N/A 1.97 N/A <1 N/A 9.49 N/A 20 308 N/A N/A 0.125 N/A N/A N/A <0.005
<5 <5 0.03 2.35 2.35 <1 <1 6.29 6.24 N/A 64 370 <0.2 <0.2 N/A N/A <5 0.017 0.017
Selenium Sodium Thallium ZincNickelPotassium
µg/L mg/L ug/L mg/Lµg/L mg/L
0.0525NENE0.24
200.8 200.7 200.8 200.7200.7 200.7
5
Tables - Page 24
Table 8. Historical surface water analytical results (ash basin)
Notes:
1.Analytical parameter abreviations:
Temp. = Temperature
DO = Dissolved oxygen
Cond. = Specific conductivity
ORP = Oxidation reduction potential
TDS = Total dissolved solids
TSS = Total suspended solids
TOC = Total organic carbon
2.Units:
˚C = Degrees Celcius
SU = Standard Units
mV = millivolts
µmhos/cm = micromhos per centimeter
NTU = Nephelometric Turbidity Unit
mg/L = milligrams per liter
µg/L = micrograms per liter
CaCO3 = calcium carbonate
3.N/A = Not applicable
4.NE = Not established
5.Highlighted values indicate values that exceed the 15A NCAC 2B Standard
6.Analytical results with "<" preceding the result indicates that the parameter
was not detected at a concentration which attains or exceeds the laboratory reporting limit.
Tables - Page 25
Table 9. Historical ash analytical results (structural fill and ash landfill)
pH % Solids Aluminum Antimony Arsenic Barium Beryllium Boron Cadmium Calcium Chromium Cobalt Copper Iron Lead Magnesium Manganese Mercury Molydenum Nickel Phosphorus
SU %mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg
100000 0.9 58 5800 63 45 3 NE 3.8 0.9 700 150 270 NE 65 1 NE 130 NE
NE 82 24 380000 400 40000 160 NE 5.6 60 8200 100000 800 NE 4600 3.1 1000 4000 4
Analytical Method 200.8 200.8 200.7 200.7 200.8 200.7 200.7 200.8 200.7 200.7 200.8 200.7 200.8 245.1 200.8 200.7
Site Name Sample Collection Date
Reuse Comp (M)1/15/2009 6.64 N/A N/A <3.81 43.7 909 N/A 52 <0.4 5730 139 N/A 117 N/A 47.4 5920 311 0.103 N/A 91 934
Reuse Comp (M)2/12/2009 7 N/A N/A <0.25 44 270 N/A 58 <0.31 2100 17 N/A 47 N/A 13 950 110 0.089 N/A 18 490
Reuse Comp (M)2/13/2009 7.06 N/A N/A <0.26 35 290 N/A 41 <0.32 2200 18 N/A 48 N/A 14 1200 130 0.082 N/A 18 510
Reuse Comp (M)2/14/2009 6.84 N/A N/A <0.25 28 250 N/A 46 <0.32 1900 17 N/A 42 N/A 11 950 260 <0.26 N/A 16 490
Reuse Comp (M)3/12/2009 6.44 N/A N/A <0.28 27 330 N/A 40 <0.35 960 15 N/A 30 N/A 9.1 990 130 0.31 N/A 18 230
Reuse Comp (M)3/13/2009 6.12 N/A N/A <0.27 27 300 N/A 33 0.063 790 12 N/A 21 N/A 9.4 640 82 0.48 N/A 13 220
Reuse Comp (M)3/14/2009 5.85 N/A N/A <0.28 27 300 N/A 38 <0.35 890 12 N/A 27 N/A 9.4 820 95 0.28 N/A 14 230
Reuse Comp (M)4/9/2009 7.59 N/A N/A <0.78 35 310 N/A <98 <0.98 3000 18 N/A 42 N/A 14 1500 150 0.15 N/A 19 290
Reuse Comp (M)4/30/2009 7.02 N/A N/A 0.868 35.4 229 N/A 24.2 2.26 1315 9.52 N/A 18.4 N/A 8.77 542 55.3 0.53 5.94 11.6 239
Reuse Comp (M)5/12/2009 6.9 N/A N/A 0.915 20.8 133 N/A 19.9 <2.54 958 9.24 N/A 14.2 N/A <7.63 364 30.8 0.151 8.14 11.4 138
Reuse Comp (M)6/4/2009 6.3 N/A N/A <11.7 25.6 300 N/A 16.4 <1.17 2210 15 N/A 23.4 N/A 8.1 909 163 0.184 4.06 14.9 215
Reuse Comp (M)7/6/2009 5.77 N/A N/A 0.987 18.1 260 N/A 4.14 1.67 940 10 N/A 15.3 N/A <2 387 217 0.158 2.9 12 150
Reuse Comp (M)8/7/2009 3.54 N/A N/A 0.993 20.6 223 N/A 14.3 5.87 1100 7.13 N/A 12.5 N/A <6 53.3 201 0.17 2.84 10.4 165
Reuse Comp (M)9/3/2009 3.83 N/A N/A 2.99 32.9 277 N/A 8.53 <0.333 1350 10.9 N/A 16.4 N/A 7.53 658 219 0.186 3.46 11.5 171
Reuse Comp (M)10/1/2009 6.44 N/A N/A <2 39.2 209 N/A 11.1 0.933 1110 27.6 N/A 39 N/A 10.7 591 103 0.203 9.93 15.7 231
Reuse Comp (M)11/5/2009 6.44 N/A N/A <2 2.47 179 N/A 5.4 <0.333 352 2.49 N/A 7 N/A <2 118 45.1 <0.129 1.24 5.7 45.2
Reuse Comp (M)12/4/2009 6.09 N/A N/A 0.8 8.6 137 N/A 5.47 0.411 459 4.65 N/A 9.2 N/A <2 151 25.1 <0.124 1.25 7.33 70.1
Reuse Comp (M)1/7/2010 5.84 N/A N/A <2 9.3 76 N/A <3.33 1.37 346 10.2 N/A 12.5 N/A <2 113 80 <0.13 3.13 11.1 52.9
Reuse Comp (M)2/4/2010 6.06 N/A N/A <2 6.02 109 N/A <3.33 1.67 483 11 N/A 15.8 N/A 2.87 159 128 <0.118 2.41 14.7 84
Reuse Comp (M)3/4/2010 6.9 N/A N/A <2 4.47 114 N/A 5.33 0.933 623 6.67 N/A 11.1 N/A <2 163 56.7 <0.139 1.53 10.9 77.3
Reuse Comp (M)4/1/2010 4.58 N/A N/A <2 4.13 88.7 N/A 4.13 <0.333 6180 <0.333 N/A 15.1 N/A <2 158 63 <0.137 1.53 11.5 58.6
Reuse Comp (M)5/6/2010 5.63 N/A N/A <2 3.29 76.7 N/A 4.49 1.02 388 5.73 N/A 12.1 N/A <2 119 68.7 <0.12 1.6 11 51.3
Reuse Comp (M)6/3/2010 4.4 N/A N/A <2 4.94 52.9 N/A 3.33 0.993 3540 3.96 N/A 10.6 N/A 2.07 170 58.3 <0.12 1.61 10 59.3
Reuse Comp (M)7/9/2010 4.85 97 N/A <2 5.12 74 N/A 3.787 0.548 373 3.42 N/A 9.2 N/A <2 105 45.7 <0.12 0.97 7.9 50.9
Reuse Comp (M)8/6/2010 6.26 79 N/A <2 2.96 140 N/A 4.09 <0.333 365 3.53 N/A 8.3 N/A <2 129 51.3 <0.121 1.22 8.2 82
Reuse Comp (M)9/2/2010 6.41 82 N/A <2 <1.33 46.8 N/A 3.33 <0.333 233 1.59 N/A 5 N/A <2 59.7 11.4 <0.122 0.46 4.2 35.1
Reuse Comp (M)10/7/2010 7.3 80.8 N/A <12.2 1.26 103 N/A <12.2 <1.22 502 5.69 N/A 10.2 N/A 1.36 214 48.5 <0.12 <3.65 9.36 40.5
Reuse Comp (M)11/4/2010 5.1 79.4 N/A <2 28.8 74.7 N/A <3.3 2.87 656 10.9 N/A 22.6 N/A 9.47 201 231 <0.12 3.47 26.3 64.9
Reuse Comp (M)12/7/2010 4.9 80.8 N/A <2 13.6 90.7 N/A 7.03 0.471 425 4.04 N/A 9.46 N/A 3.13 140 28.2 0.12 1.93 8.71 55.6
Reuse Comp (M)1/5/2011 7.8 83.6 N/A <2 3.5 67.9 N/A <3.3 1.02 918 3.87 N/A 12.7 N/A <2 218 80.9 <0.12 1.8 11.8 47.7
Reuse Comp (M)2/3/2011 6.5 80.6 N/A <2 7.93 109 N/A <3.3 0.491 407 3.87 N/A 9.1 N/A <2 128 33.8 <0.12 1.09 8.43 58.9
Reuse Comp (M)3/3/2011 7.1 80.9 N/A <2 6.03 147 N/A 4.08 0.531 477 3.96 N/A 9.5 N/A 4.3 157 26.4 <0.12 1.74 7.42 56.7
Reuse Comp (M)4/7/2011 6.6 81.9 N/A <2 5.33 164 N/A <3.3 <0.67 535 4.37 N/A 10.4 N/A <2 429 64.1 <0.12 5.45 7.31 83.3
Reuse Comp (M)5/5/2011 6.1 76.2 N/A <2 10.4 214 N/A 3.87 0.445 594 5.75 N/A 13 N/A 3.05 454 44.8 <0.13 1.49 9.2 91.7
Reuse Comp (M)6/2/2011 8.3 86.1 N/A <2 3.31 321 N/A 3.95 <0.33 1180 4.97 N/A 12.6 N/A <2 239 89.5 <0.11 1.42 11.1 123
Reuse Comp (M)7/7/2011 7.4 55.7 N/A <2 7.49 278 N/A 5.6 <0.33 1050 4.81 N/A 11.6 N/A <2 230 39.7 0.18 1.06 8.03 95.7
Reuse Comp (M)8/4/2011 4.9 80 N/A <2 20.4 161 N/A 4.15 <0.33 1170 8.81 N/A 16.1 N/A 3.05 411 105 <0.12 2.65 11.3 99.5
Reuse Comp (M)9/1/2011 6.1 76.4 N/A <2 10.8 199 N/A 4.85 <0.33 670 5.23 N/A 12.9 N/A <2 214 29.1 <0.13 1.17 8.29 106
Reuse Comp (M)10/6/2011 5.6 70.9 N/A <20 <13.3 88.7 N/A <33.3 <3.33 360 5.56 N/A 9.48 10400 <20 124 61.7 1.1 <0.05 8.07 570
Reuse Comp (M)11/4/2011 6 74.4 N/A <2 13.1 156 N/A 6.06 0.681 747 8.43 N/A 18.3 N/A 4.46 303 75.7 <0.13 1.78 11.7 112
Reuse Comp (M)11/30/2011 6.4 77.2 N/A <2 15.3 161 N/A 6 <0.33 677 6.57 N/A 12.9 N/A 3.76 239 44.2 <0.13 2.01 9.67 91.4
Reuse Comp (M)1/4/2012 7.6 71.1 N/A <2 8.34 150 N/A 5.71 0.354 679 5.72 N/A 12.6 N/A <2 227 31.9 <0.14 1.34 8.3 71.3
Reuse Comp (M)2/3/2012 7.1 76.6 N/A <2 9.48 89.7 N/A 4.8 <0.333 791 7.6 N/A 13.6 N/A 2.49 222 57.8 0.12 1.91 10.5 56.8
Reuse Comp (M)3/1/2012 6.9 N/A N/A <2 9.64 106 N/A 5.01 0.534 842 5.99 N/A 13.6 N/A 2.46 243 35.4 0.23 1.63 10.1 58.2
Reuse Comp (M)4/5/2012 N/A N/A N/A <2 4.72 112 N/A 9.79 0.641 1150 10.8 N/A 17.4 N/A <2 335 66.9 N/A 1.98 15.2 140
Reuse Comp (M)5/3/2012 6.9 N/A N/A <2 3.11 104 N/A 5.77 0.469 1040 8.75 N/A 13 N/A <2 267 46.1 <0.13 1.07 9.46 44.9
Reuse Comp (M)6/7/2012 6.8 N/A N/A <2 4.77 136 N/A 6.87 0.55 1050 9.23 N/A 15.4 N/A 3.39 286 55.9 <0.12 1.72 10.8 2.69
Reuse Comp (M)7/5/2012 8.2 N/A N/A <2 7.81 134 N/A 8.03 0.674 1050 9.33 N/A 16.1 N/A 2.95 346 41.2 <0.116 1.61 12.8 251
Reuse Comp (M)8/3/2012 6.6 N/A N/A <10 18.1 221 N/A <16.7 <1.67 1260 13.2 N/A 24.5 N/A <10 484 46.6 <0.143 1.93 17.9 131
Reuse Comp (M)9/11/2012 3 N/A N/A <2 9.56 142 N/A <3.33 1.1 832 13.8 N/A 14.3 N/A 2.5 280 99 <0.121 1.49 12.6 66.4
Reuse Comp (M)10/4/2012 7.3 N/A N/A <20 20.3 240 N/A <33.3 <3.33 1290 14.9 N/A 26.9 N/A <20 546 38.3 <0.138 <3.33 19.8 1400
Reuse Comp (M)11/1/2012 7.6 N/A N/A <10 17.7 299 N/A <16.7 <1.67 1240 12.4 N/A 22.3 N/A <10 500 40.9 <0.126 2.06 17.3 680
Reuse Comp (M)12/11/2012 3.2 N/A N/A <20 13.5 273 N/A <33.3 <3.33 1260 20.7 N/A 23.4 N/A <20 420 144 <0.111 <3.33 20.9 131
Reuse Comp (M)1/4/2013 3.3 N/A N/A <20 15.5 199 N/A <33.3 <3.33 796 14.4 N/A 15.9 N/A <20 294 78.1 <0.127 <3.33 13.7 1820
Reuse Comp (M)2/13/2013 4.2 N/A N/A <20 <13.3 139 N/A <33.3 <3.33 1210 17.8 N/A 17.2 N/A <20 363 137 <0.115 <3.33 16.1 846
Reuse Comp (M)3/8/2013 7.5 N/A N/A <20 <13.3 170 N/A <33.3 <3.33 1370 12.7 N/A 18.5 N/A <20 400 56.5 <0.137 <3.33 17.7 122
Reuse Comp (M)4/8/2013 6.9 N/A N/A <20 <13.3 187 N/A <33.3 <3.33 1170 7.6 N/A 15.8 N/A <20 469 34.5 <0.138 <3.33 14.7 117
Reuse Comp (M)5/9/2013 5.9 N/A N/A <20 13.5 101 N/A <33 <3.3 1690 9.99 N/A 12.1 N/A <20 307 35.8 <0.128 <3.3 12.2 2130
Reuse Comp (M)6/5/2013 6.1 N/A N/A <20 <13.3333 42.3 N/A 200 <3.33333 6390 22.5 N/A 11.9 N/A <20 845 59 <0.132 8.77 30.5 276
Reuse Comp (M)7/17/2013 6.9 N/A N/A <20 <13.3333 189 N/A <33.3333 <3.33333 1010 8.05 N/A 16.5 N/A <20 278 18.8 <0.233 <3.33333 10.4 92.5
Reuse Comp (M)8/12/2013 7.59 N/A N/A <20 <13.3333 121 N/A <33.3333 <3.33333 542 4.41 N/A 11.2 N/A <20 191 8.95 0.486 <3.33333 7.23 713
Reuse Comp (M)9/9/2013 7.13 N/A N/A <20 14.6 208 N/A <33.3333 <3.33333 1610 15.8 N/A 25.7 N/A <20 593 54.5 <0.133 <3.33333 21.1 1490
IHSB Industrial Health-Based PSRG
Units
Analytical Parameter
Field Measurement
IHSB Protection of Groundwater PSRG
Tables - Page 26
Table 9. Historical ash analytical results (structural fill and ash landfill)
Analytical Method
Site Name Sample Collection Date
Reuse Comp (M)1/15/2009
Reuse Comp (M)2/12/2009
Reuse Comp (M)2/13/2009
Reuse Comp (M)2/14/2009
Reuse Comp (M)3/12/2009
Reuse Comp (M)3/13/2009
Reuse Comp (M)3/14/2009
Reuse Comp (M)4/9/2009
Reuse Comp (M)4/30/2009
Reuse Comp (M)5/12/2009
Reuse Comp (M)6/4/2009
Reuse Comp (M)7/6/2009
Reuse Comp (M)8/7/2009
Reuse Comp (M)9/3/2009
Reuse Comp (M)10/1/2009
Reuse Comp (M)11/5/2009
Reuse Comp (M)12/4/2009
Reuse Comp (M)1/7/2010
Reuse Comp (M)2/4/2010
Reuse Comp (M)3/4/2010
Reuse Comp (M)4/1/2010
Reuse Comp (M)5/6/2010
Reuse Comp (M)6/3/2010
Reuse Comp (M)7/9/2010
Reuse Comp (M)8/6/2010
Reuse Comp (M)9/2/2010
Reuse Comp (M)10/7/2010
Reuse Comp (M)11/4/2010
Reuse Comp (M)12/7/2010
Reuse Comp (M)1/5/2011
Reuse Comp (M)2/3/2011
Reuse Comp (M)3/3/2011
Reuse Comp (M)4/7/2011
Reuse Comp (M)5/5/2011
Reuse Comp (M)6/2/2011
Reuse Comp (M)7/7/2011
Reuse Comp (M)8/4/2011
Reuse Comp (M)9/1/2011
Reuse Comp (M)10/6/2011
Reuse Comp (M)11/4/2011
Reuse Comp (M)11/30/2011
Reuse Comp (M)1/4/2012
Reuse Comp (M)2/3/2012
Reuse Comp (M)3/1/2012
Reuse Comp (M)4/5/2012
Reuse Comp (M)5/3/2012
Reuse Comp (M)6/7/2012
Reuse Comp (M)7/5/2012
Reuse Comp (M)8/3/2012
Reuse Comp (M)9/11/2012
Reuse Comp (M)10/4/2012
Reuse Comp (M)11/1/2012
Reuse Comp (M)12/11/2012
Reuse Comp (M)1/4/2013
Reuse Comp (M)2/13/2013
Reuse Comp (M)3/8/2013
Reuse Comp (M)4/8/2013
Reuse Comp (M)5/9/2013
Reuse Comp (M)6/5/2013
Reuse Comp (M)7/17/2013
Reuse Comp (M)8/12/2013
Reuse Comp (M)9/9/2013
IHSB Industrial Health-Based PSRG
Units
Analytical Parameter
IHSB Protection of Groundwater PSRG
Potassium Selenium Silver Sodium Strontium Thallium Zinc
mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg
NE 2.1 3.4 NE NE 0.28 1200
NE 1000 1000 NE 100000 2 62000
200.7 200.8 200.7 200.8 200.7
21130 6.3 <0.19 2230 N/A N/A 96
2300 13 0.31 270 N/A N/A 25
2500 7.6 <0.32 290 N/A N/A 27
2100 9.2 <0.32 230 N/A N/A 29
1700 19 0.18 130 N/A N/A 25
1200 21 <0.34 110 N/A N/A 17
1500 18 <0.35 130 N/A N/A 19
2400 15 <0.98 250 N/A N/A 37
829 21.6 <0.342 123 N/A N/A 18.2
473 14.2 <0.424 76.5 N/A N/A 11.9
1050 13 <1.17 <233 N/A N/A 18.7
347 10.7 <0.333 57.5 N/A N/A 8.48
463 9.07 <0.333 69.3 N/A N/A 12.9
535 11.9 <0.333 98.7 N/A N/A 12.5
628 37 <0.333 100 N/A N/A 47.7
137 28.6 <0.333 41.9 N/A N/A 2.77
210 5.8 <0.333 39.5 N/A N/A 5.13
86 <2 <0.333 34.6 N/A N/A 5.07
125 4.67 <0.333 38.8 N/A N/A 4.53
167 2.67 <0.333 43.3 N/A N/A 4.67
134 2.13 <0.333 33 N/A N/A 4
115 <2 <0.333 36 N/A N/A 4.91
122 <2 <0.333 39.9 N/A N/A 4.65
115 <2 <0.333 36.1 N/A N/A 3.07
146 <2 <0.333 47.5 N/A N/A 3.61
75 <2 <0.333 30.4 N/A N/A 1.79
406 <2.43 <1.22 <243 N/A N/A <12.2
117 8.89 <0.33 41 N/A N/A 12.7
195 <2 <0.33 42 N/A N/A 5.76
186 <2 <0.33 39.4 N/A N/A 9.9
175 4.13 <0.33 38.6 N/A N/A 6.54
193 4 <0.3 38.2 N/A N/A 6.39
449 3.51 <0.33 39.5 N/A N/A 7.72
521 5.5 <0.333 55.8 N/A N/A 9.48
272 <2 <0.33 71.3 N/A N/A 23.2
316 <2 <0.33 73.9 N/A N/A 5.55
504 6.18 <0.33 72.2 N/A N/A 10.5
318 3.92 <0.33 58.1 N/A N/A 6.39
149 <20 <3.33 34.7 N/A N/A 4.85
426 5.72 <0.33 63.9 N/A N/A 10.6
317 9.04 <0.33 61.4 N/A N/A 8.22
318 3.53 <0.333 61.9 N/A N/A 5.43
231 3.76 <0.333 48.4 N/A N/A 12.8
318 2.67 <0.333 65.9 N/A N/A 6.94
594 2.32 <0.333 79.1 N/A N/A 8.69
435 2.86 <0.333 65.5 N/A N/A 5.32
493 3.19 <0.333 80.2 N/A N/A 12
756 3.72 <0.333 92.1 N/A N/A 10.2
918 <10 <1.67 132 N/A N/A 13.2
370 <2 <0.333 59.7 N/A N/A 7.57
1120 <20 <3.33 169 N/A N/A 16
949 <10 <1.67 132 N/A N/A 12.9
639 <20 <3.33 122 N/A N/A 26.1
630 <20 <3.33 77.4 N/A N/A 14.9
378 <20 <3.33 77.1 N/A N/A 13.3
647 <20 <3.33 124 N/A N/A 16.6
874 <20 <3.33 137 N/A N/A 10.2
591 <20 <3.3 132 N/A N/A 8.93
507 <20 <3.33333 500 N/A N/A 197
742 <20 <3.33333 136 N/A N/A 10.7
552 <20 <3.33333 86.3 N/A N/A 7.04
1060 <20 <3.33333 200 N/A N/A 22.7
Tables - Page 27
Table 9. Historical ash analytical results (structural fill and ash landfill)
Notes:
1.Units:
SU = Standard Units
mg/kg = milligrams per kilogram
2.N/A = Not applicable
NE = Not established
3.Sample depth interval in parentheses
Tables - Page 28
Table 10. Historical ash leachate analytical results (ash basin)
pH Aluminum Antimony Arsenic Barium Beryllium Boron Cadmium Calcium Chloride Chromium Cobalt Copper Flouride Iron Lead Magnesium
SU mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L
6.5 - 8.5 NE 0.001*0.01 0.7 0.004*0.7 0.002 NE 250 0.01 0.001*1 2 0.3 0.015 NE
Analytical Method 200.8 200.8 200.7 200.7 200.8 200.7 200.7 200.8 200.7 200.7 200.8 200.7
Site Name Protocol Sample Collection Date
Fly Ash SPLP 9/24/2010 N/A N/A 0.018 0.061 0.13 N/A 1.23 <0.001 68.5 <1 <0.005 N/A <0.01 0.71 <0.05 <0.005 3.34
Fly Ash TCLP 9/24/2010 7.2 N/A N/A <0.1 0.266 N/A N/A <0.01 N/A N/A <0.05 N/A N/A N/A N/A <0.05 N/A
Reuse Comp SPLP 10/7/2010 N/A N/A <0.01 <0.01 0.061 N/A <0.5 <0.001 <1 <1 <0.005 N/A 0.078 <0.1 <0.005 <1 <0.15
Reuse Comp TCLP 10/7/2010 7.3 N/A N/A <0.1 0.517 N/A N/A <0.01 N/A N/A <0.05 N/A N/A N/A N/A 0.086 N/A
Reuse Comp TCLP 10/6/2011 5.6 N/A N/A <0.1 1.08 N/A N/A <0.01 N/A N/A <0.05 N/A N/A N/A N/A 0.133 N/A
Field Measurement
Analytical Parameter
Units
15A NCAC 02L .0202(g) Groundwater Quality Standard
Tables - Page 29
Table 10. Historical ash leachate analytical results (ash basin)
Analytical Method
Site Name Protocol Sample Collection Date
Fly Ash SPLP 9/24/2010
Fly Ash TCLP 9/24/2010
Reuse Comp SPLP 10/7/2010
Reuse Comp TCLP 10/7/2010
Reuse Comp TCLP 10/6/2011
Analytical Parameter
Units
15A NCAC 02L .0202(g) Groundwater Quality Standard
Manganese Mercury Molydenum Nickel Nitrate as N Phosphorus Potassium Selenium Silver Sodium Strontium Sulfate Thallium Zinc
mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L mg/L
0.05 0.001 NE 0.1 10 NE NE 0.02 20 NE NE 250 0.0002*1
200.8 245.1 200.8 200.7 200.7 200.8 200.7 200.8 200.7
<0.15 <0.001 N/A <0.01 <0.1 N/A 10.5 0.23 <0.005 N/A N/A 179 N/A <0.05
N/A <0.01 N/A N/A N/A N/A N/A 0.206 <0.05 N/A N/A N/A N/A N/A
<0.01 <0.001 N/A <1 <0.1 <0.1 <0.01 <0.005 <0.05 N/A N/A 1.44 N/A <0.05
N/A <0.01 N/A N/A N/A N/A N/A <0.1 <0.05 N/A N/A N/A N/A N/A
N/A <0.01 N/A N/A N/A N/A N/A <0.1 <0.05 N/A N/A N/A N/A N/A
Tables - Page 30
Table 10. Historical ash leachate analytical results (ash basin)
Notes:
1.TDS = Total dissolved solids
SPLP = Synthetic Precipitation Leaching Procedure
TCLP = Toxicity Characteristic Leaching Procedure
2.Units:
mg/L = milligrams per liter
µg/L = micrograms per liter
3.* IMAC (interim maximum allowable concentration)
4.Sample depth interval in parentheses
5.Highlighted values indicate values that exceed the 15A NCAC 2L Standard
6.Analytical results with "<" preceding the result indicates that the parameter
was not detected at a concentration which attains or exceeds the laboratory
reporting limit
Tables - Page 31
Table 11. Historical landfill leachate analytical results (RAB Ash Landfill)
Temp Cond.DO pH ORP Turbidity Aluminum Antimony Arsenic Barium Beryllium Boron Cadmium Calcium Chloride Chromium Cobalt
˚C µmhos/cm µg/L SU mV NTU µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L
NE NE NE 6.5 - 8.5 NE NE NE 1*10 700 4*700 2 NE 250000 10 1*
Analytical Method 200.8 200.8 200.7 200.7 200.8 200.7 200.7 200.8
Site Name Sample Collection Date
AS-LCS-C1 12/1/2011 17.06 1445 N/A 4.07 N/A 21 N/A N/A 92.1 50 N/A 12900 2.5 N/A 19000 <5 N/A
AS-LCS-C1 3/5/2012 14.34 986 N/A 3.93 N/A 5 N/A <1 81.1 43 N/A 7520 1.74 N/A 13000 <5 N/A
AS-LCS-C1 9/24/2012 21.87 3175 N/A 3.85 N/A 4 N/A N/A 464 46 N/A 33100 10.6 N/A 35000 <5 N/A
AS-LCS-C1 3/4/2013 16.17 2901 5880 3.87 503 3.25 N/A N/A 464 41.6 N/A 26100 <10 N/A 30400 <5 N/A
AS-LCS-C1 9/26/2013 21.23 4450 5570 3.97 513 12.4 N/A N/A 329 52.7 N/A 44800 10.1 N/A 46900 <5 N/A
AS-LCS-C1 3/5/2014 18.52 3694 4120 3.91 496 5.18 N/A N/A 410 56.5 N/A 36000 <10 N/A 51900 <5 N/A
AS-LCS-C1 9/2/2014 20.06 5176 1930 4.07 441 2.9 N/A N/A 337 46.5 N/A 50800 12.3 N/A 71300 <5 N/A
AS-LCS-C2 12/1/2011 14.85 152 N/A 5.75 N/A 2 N/A N/A 1.27 29 N/A 56 <1 N/A 1700 <5 N/A
AS-LCS-C2 3/5/2012 14.07 1296 N/A 4.4 N/A 27 N/A <1 40.2 58 N/A 2160 3.61 N/A 2300 7 N/A
AS-LCS-C2 9/24/2012 25.1 261 N/A 4.68 N/A 11 N/A N/A 14.8 24 N/A 403 <5 N/A 2400 <5 N/A
AS-LCS-C2 3/4/2013 13.98 644 7540 3.78 470 2.9 N/A N/A 39.9 21 N/A 839 <10 N/A 3770 <5 N/A
AS-LCS-C2 9/26/2013 22.76 1068 3440 4.01 662 4.16 N/A N/A 28.6 40.9 N/A 5460 <10 N/A 4820 <5 N/A
AS-LCS-C2 3/5/2014 18.55 1168 3910 3.89 521 1.21 N/A N/A 86.2 57.5 N/A 7330 <10 N/A 13700 <5 N/A
AS-LCS-C2 9/2/2014 20.52 3097 1710 4.01 474 2.3 N/A N/A 208 45.7 N/A 30700 <10 N/A 56000 <5 N/A
Analytical Parameter
Units
15A NCAC 02L .0202(g) Groundwater Quality Standard
Field Measurements
Tables - Page 32
Table 11. Historical landfill leachate analytical results (RAB Ash Landfill)
Analytical Method
Site Name Sample Collection Date
AS-LCS-C1 12/1/2011
AS-LCS-C1 3/5/2012
AS-LCS-C1 9/24/2012
AS-LCS-C1 3/4/2013
AS-LCS-C1 9/26/2013
AS-LCS-C1 3/5/2014
AS-LCS-C1 9/2/2014
AS-LCS-C2 12/1/2011
AS-LCS-C2 3/5/2012
AS-LCS-C2 9/24/2012
AS-LCS-C2 3/4/2013
AS-LCS-C2 9/26/2013
AS-LCS-C2 3/5/2014
AS-LCS-C2 9/2/2014
Analytical Parameter
Units
15A NCAC 02L .0202(g) Groundwater Quality Standard
Copper Fluoride Iron Lead Manganese Mercury Nickel Nitrate an N Selenium Silver Sulfate Thallium TDS Zinc
µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L µg/L
1000 2000 300 15 50 1 100 10000 20 20 250000 0.2*500000 1000
200.7 200.7 200.8 200.8 245.1 200.7 200.8 200.8 220.7
71 1900 148 1.29 5630 <0.05 279 7300 72.9 <5 770000 N/A 85000 335
45 1300 86 <1 3370 <0.05 168 5600 49.3 <5 470000 <1 741000 203
306 3000 352 <5 18400 <0.05 897 12000 1400 <5 1300000 N/A 3600000 1200
190 3450 128 <10 14000 <0.05 622 9630 1980 <5 1730000 N/A 2670000 767
129 3260 397 <10 21600 0.063 807 8900 1370 <5 2910000 N/A 4130000 1010
119 2640 224 <10 17000 0.122 663 13800 85.1 <5 1010000 N/A 3040000 981
283 3810 172 <10 27100 0.07 947 16200 68.4 <5 3640000 N/A 4650000 1340
<5 100 10 <1 421 <0.05 5 430 20.3 <5 52000 N/A 1300000 6
95 3300 174 <1 3660 <0.05 261 4300 71.8 <5 730000 4.11 1110000 357
10 <1000 1300 <5 2150 <0.05 28 <23 47.6 <5 120000 N/A 210000 31
45.8 1040 139 <10 4950 <0.05 65.8 1690 194 <5 308000 N/A 444000 97
40.8 1140 168 <10 5340 <0.05 81.3 2430 158 <5 634000 N/A 921000 122
42.4 1220 43.7 <10 12300 <0.05 155 15800 138 <5 627000 N/A 968000 264
107 3330 117 <10 30200 <0.05 213 60800 157 <5 1810000 N/A 2790000 452
Tables - Page 33
Table 11. Historical landfill leachate analytical results (RAB Ash Landfill)
Notes:
1.TDS = Total dissolved solids
DO = Dissolved oxygen
Cond. = Specific conductivity
ORP = Oxidation reduction potential
TDS = Total dissolved solids
TSS = Total suspended solids
TOC = Total organic carbon
2.Units:
˚C = Degrees Celcius
SU = Standard Units
mV = millivolts
NTU = Nephelometric Turbidity Unit
µmhos/cm = micromhos per centimeter
mg/L = milligrams per liter
µg/L = micrograms per liter
3.* IMAC (interim maximum allowable concentration)
4.Highlighted values indicate values that exceed the 15A NCAC 2L Standard
5.Analytical results with "<" preceding the result indicates that the parameter
was not detected at a concentration which attains or exceeds the laboratory reporting limit
Tables - Page 34
Table 12. August 2014 Seep Sample Analytical Results
Temp.Cond.pH Aluminum Antimony Arsenic Barium Boron Cadmium Calcium COD Chloride Chromium Copper Flow Fluoride Hardness
˚C µmhos/cm SU mg/L ug/L ug/L mg/L mg/L ug/L mg/L mg/L mg/L ug/L ug/L MGD mg/L mg/L (CaCO3)
NE NE 6.0 - 9.0 0.087 5.6 10 1 NE 2 NE NE NE 50 0.007 N/A 2 100
EPA 200.7 EPA 200.8 EPA 200.8 EPA 200.7 EPA 200.7 EPA 200.8 EPA 200.7 HACH 8000 EPA 300.0 EPA 200.8 EPA 200.8 N/A EPA 300.0 EPA 200.7
S-1 23.8 107 6.63 0.996 <1 <1 0.044 <0.05 <1 7.34 <20 4.3 1.42 <1 0.0004 0.11 31.9
S-2 20.9 229 6.33 0.467 <1 <1 0.114 0.871 <1 7.25 <20 49 <1 <1 0.0025 0.1 74.4
S-3 21.5 447 6.95 0.039 <1 <1 0.044 0.555 <1 61.7 20 32 <1 <1 0.0083 0.13 203
S-4 21.6 524 6.92 0.022 <1 <1 0.047 0.713 <1 73.4 <20 41 <1 <1 0.0008 <0.1 251
S-5 17.6 326 5.56 <0.005 <1 <1 0.208 0.927 <1 20.7 <20 59 <1 <1 0.0023 <0.1 111
S-6 17.6 341 4.67 0.21 <1 <1 0.307 1.01 <1 19.8 <20 62 <1 1.14 0.0002 0.11 112
S-7 20.4 222 5.64 0.083 <1 <1 0.057 0.934 <1 17.8 <20 7.8 <1 <1 0.0002 <0.1 76
S-8 23.6 555 8.11 0.01 <1 <1 0.06 0.606 <1 97.6 <20 7.5 <1 <1 0.0002 0.17 292
S-9 19 717 7.52 0.254 <1 <1 0.029 1.49 <1 138 <20 9.1 <1 1.31 0.0002 <0.5 413
N/A N/A N/A N/A N/A <1 N/A N/A <1 N/A N/A N/A <1 2.8 N/A N/A N/A
N/A N/A N/A N/A N/A <1 N/A N/A <1 N/A N/A N/A <1 2.6 N/A N/A N/A
Units
Analytical Parameter
Seep Monitoring Location1
Lake Wylie-Upstream2,3
Lake Wylie-Downstream2,3
Site Name
15A NCAC 02B .0200 Surface Water Quality Standard
Tables - Page 35
Table 12. August 2014 Seep Sample Analytical Results
S-1
S-2
S-3
S-4
S-5
S-6
S-7
S-8
S-9
Units
Analytical Parameter
Seep Monitoring Location1
Lake Wylie-Upstream2,3
Lake Wylie-Downstream2,3
Site Name
15A NCAC 02B .0200 Surface Water Quality Standard
Iron Lead Magnesium Manganese Mercury Molybdenum Nickel Oil and
Grease Selenium Sulfate TDS Thallium TSS Zinc
mg/L ug/L mg/L mg/L ug/L ug/L ug/L mg/L ug/L mg/L mg/L ug/L mg/L mg/L
1 25 NE 200 0.012 160 25 see note 2 5 250 500 0.24 NE 50
EPA 200.7 EPA 200.8 EPA 200.7 EPA 200.7 EPA 245.1 EPA 200.8 EPA 200.8 EPA 1664B EPA 200.8 EPA 300.0 SM2540C EPA 200.8 SM2540D EPA 200.7
1.86 <1 3.29 0.356 <1 <1 <1 <5 <1 1.4 110 <0.2 38 <0.005
1.25 <1 13.7 0.305 <1 <1 1.58 <5 <1 10 170 <0.2 8 <0.005
0.136 <1 12 0.131 <1 <1 <1 <5.0 <1 26 300 <0.2 <5 <0.005
0.215 <1 16.4 0.31 <1 <1 <1 <5 <1 21 320 <0.2 <5 <0.005
<0.01 <1 14.4 1.45 <1 <1 8.23 <5 <1 42 230 <0.2 <5 0.011
0.015 <1 15.2 2.25 <1 <1 2.29 <5.0 <1 55 220 0.273 <5 <0.005
0.113 <1 7.69 0.395 <1 <1 <1 <5 <1 74 180 <0.2 <5 <0.005
0.011 <1 11.7 <0.005 <1 <1 <1 <5 <1 87 360 <0.2 <5 <0.005
0.942 <1 16.5 0.998 <1 <1 2.78 <5 <1 180 500 <0.2 <5 0.283
N/A <1 N/A N/A <1 N/A N/A N/A <1 N/A 54 N/A N/A 3.08
N/A <1 N/A N/A <1 N/A N/A N/A <1 N/A 53 N/A N/A <2
Tables - Page 36
Table 12. August 2014 Seep Sample Analytical Results
Notes:
1.Analytical parameter abreviations:
Temp. = Temperature
Cond. = Specific conductivity
TDS = Total dissolved solids
TSS = Total suspended solids
2.Units:
˚C = Degrees Celcius
SU = Standard Units
µmhos/cm = micromhos per centimeter
mg/L = milligrams per liter
µg/L = micrograms per liter
CaCO3 = calcium carbonate
3.take the lowest LC50 available for the particular type of OG you have (or similar OG)
and multiply it by a safety factor of 0.01 to obtain the criteria
4.N/A = Not applicable
5.NE = Not established
6.Highlighted values indicate values that exceed the 15A NCAC 2B Standard
7.Analytical results with "<" preceding the result indicates that the parameter
was not detected at a concentration which attains or exceeds the laboratory reporting limit
Tables - Page 37
Appendix A
Notice of Regulatory Requirements Letter from
John E. Skvarla, III, Secretary, State of North
Carolina, to Paul Newton, Duke Energy, dated
August 13, 2014.
Appendix B
Review of Groundwater Assessment Work
Plan Letter from S. Jay Zimmerman, Chief,
Water Quality Regional Operations Section,
NCDENR, To Harry Sideris, Duke Energy,
dated November 4, 2014.
1