HomeMy WebLinkAbout23035 Theron_ WP-DEQ Approval 20190828
August 28, 2019
Sent Via E-Mail
Ralph McGee, P.G. Hart & Hickman 2923 South Tryon Street, Suite 100
Charlotte, North Carolina 28203
RMcGee@harthickman.com
Subject: Work Plan Approval- Supplement Brownfields Assessment Work Plan
Chadborn Mill and Theron Properties
500 and 508 Charles Ave. Brownfields Project No. 20086-16-6 and 23035-19-060
Dear Mr. McGee,
The Department of Environmental Quality (DEQ) Brownfields Program received the Supplemental Brownfields Assessment Work Plan dated August 20, 2019 for the above referenced Brownfields Property. DEQ Brownfields reviewed this document, and determined that comments made by DEQ
Brownfields to previous versions of this work plan have been incorporated as requested. Therefore,
DEQ Brownfields approves the Work Plan.
Please be advised that this approval from DEQ Brownfields does not waive any applicable
requirement to obtain any necessary permits, licenses or certifications which may be required from
other state or local entities. If you have questions about this correspondence or require additional
information, please feel free to contact me by phone at 704/661-0330 or by email at
carolyn.minnich@ncdenr.gov
Sincerely,
Carolyn Minnich
Carolyn Minnich
Brownfields Project Manager
ec: Christine Schaefer, CSchaefer@harthickman.com
Will Smith, dwsmith@camdenliving.com
Duane Carter, dcanter@camdenliving.com
Via Email
August 28, 2019
NCDEQ – Division of Waste Management
Brownfields Program
1646 Mail Service Center
Raleigh, NC 27699-1646
Attention: Ms. Carolyn Minnich
Re: Supplemental Brownfields Assessment Work Plan
Chadbourn Mill and Theron Properties
500 and 508 Charles Avenue
Charlotte, North Carolina
Brownfields Project Nos. 20086-16-060 & 23035-19-060
H&H Job No. CAM-010
Dear Carolyn:
1.0 Introduction
On behalf of CUSA NC Holdings, LP (Prospective Developer or PD), Hart & Hickman, PC
(H&H) has prepared this Supplemental Brownfields Assessment Work Plan (Work Plan) for the
Theron Properties Brownfields property (Brownfields Project No. 23035-19-060) and Chadbourn
Mill Brownfields property (Brownfields Project No. 20086-16-060) located at 500 and 508
Charles Avenue in Charlotte, Mecklenburg County, North Carolina (Site). The Site is comprised
of two parcels totaling approximately 4.3 acres of land (Parcel ID Nos. 08306705 and
08306808). Please note that the proposed scope of work outlined in this Work Plan does not
include assessment activities for the northern parcel included as part of the Theron Properties
Brownfields property (Parcel ID No. 08306808) or the western parcel included as part of the
Chadbourn Mill Brownfields property (Parcel ID No. 08306707).
Ms. Carolyn Minnich
August 28, 2019
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The Site is located in a rapidly densifying area of the NoDa neighborhood in close proximity to
the LYNX Blue Line light rail. The Site is bounded by Charles Avenue to the north, Matheson
Avenue to the northeast, N. Davidson Street to the east, Jordan Place to the south, and the
western portion of the Chadbourn Mill Brownfields property to the west-northwest. The
northern portion of the Site (Theron Properties) is developed with three buildings including an
approximately 1,400 square foot (sq ft) single family residence (western building), an
approximately 2,500 sq ft one story light industrial warehouse (eastern building), and an
approximately 2,900 sq ft one story light industrial warehouse (central building).
The central warehouse building has most recently been used for blacksmith and artistic metal
sculpture operations and the eastern warehouse has most recently been occupied by an antique
furniture and kitchen cabinetry refinishing business. Remaining portions of the Site consist of
undeveloped vacant land historically used for Chadbourn Mill employee parking and single-
family residential uses. A Site location map is provided as Figure 1, and the Site and
surrounding area are shown in Figure 2.
Current redevelopment plans include demolition of the Site structures and construction of multi-
tenant mixed residential and commercial use buildings, a parking garage, driveways, and open
courtyards. Grading plans for the redevelopment generally include cut in western portions of the
Site and fill in eastern portions of the Site. However, results of recently completed geotechnical
assessment activities conducted at the Site identified undocumented urban fill unsuitable for
construction purposes at varying depths in several areas at the Site.
A Brownfields Agreement between the North Carolina Department of Environmental Quality
(DEQ) and Faison-Chadbourn Mill, LLC was recorded on September 1, 2017. The Theron
Properties received eligibility into the DEQ Brownfields Program in a letter dated July 5, 2019.
As part of the Brownfields process for Theron Properties, a kick-off/data gap meeting with the
PD, DEQ Brownfields personnel, and H&H was held on August 5, 2019 to discuss historical
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uses of the Site, available environmental information, proposed redevelopment plans, data gaps,
and the proposed schedule for completing the Brownfields agreement.
Based on the redevelopment plan for the Site and conversations with DEQ Brownfields during
the recent kick-off/data gap meeting, H&H proposes to conduct in-situ soil characterization
assessment activities at the Site to evaluate the potential for impact and to characterize soil that
may be removed from the Site as part of grading and redevelopment activities.
In addition to the proposed in-situ soil characterization assessment activities, H&H proposes to
complete supplemental vapor intrusion assessment activities at the Site. Results of previous
vapor intrusion assessment activities completed at the Site in September 2016 identified low
levels of chlorinated solvents and petroleum-related compounds at concentrations exceeding the
DEQ screening criteria in a soil gas sample collected in the southwestern portion of the Site. No
compounds were detected above the DEQ screening criteria in other soil gas samples collected at
the Site. Risk calculation using the compound concentrations in Site soil gas do not indicate a
significant potential vapor intrusion risk. However, based on discussions with DEQ
Brownfields, additional assessment will be needed to evaluate current soil gas concentrations in
the area of the proposed redevelopment. H&H proposes to complete soil gas assessment
activities within the footprints of the proposed buildings to further evaluate the potential for
structural vapor intrusion.
The proposed supplemental Brownfields assessment scope of work is outlined in the following
sections.
2.0 Supplemental Brownfields Assessment Activities
The proposed in-situ soil characterization assessment and soil gas assessment activities described
below will be performed in general accordance with DEQ Inactive Hazardous Sites Branch
(IHSB) Guidelines for Assessment and Cleanup (Guidelines) dated October 2015, the DEQ
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Division of Waste Management (DWM) Vapor Intrusion Guidance (VI Guidance) dated March
2019, and the most recent versions of the U.S. Environmental Protection Agency (EPA) Region
IV Science and Ecosystem Support Division (SESD) Field Branches Quality System and
Technical Procedures guidance.
Prior to conducting subsurface drilling activities at the Site, H&H will contact North Carolina
811, the public utility locator service, to mark subsurface utilities. H&H will also contract with a
private utility locator to identify and mark locations of sub-grade utilities at the Site that may not
be marked by the public locator. In addition, prior to boring advancement, a decontaminated
stainless-steel hand auger will be advanced to a depth of approximately 5 feet below ground
surface (ft bgs) at the proposed deeper boring locations to further clear for potential subsurface
utilities (unless conditions indicate that further advancement with a hand auger is warranted).
Investigation derived waste (IDW) generated during the assessment activities will be spread
evenly across the Site unless in-field observation such as staining or free product indicate the soil
needs to be containerized in 55-gallon drums and staged on-Site pending analytical results of a
composite IDW sample. Based on laboratory analytical results of the IDW samples, the drums
will be transported off-Site to a suitable facility for disposal.
Following sample collection, each soil boring will be abandoned and the surface restored similar
to pre-drilling conditions. Additionally, each sample location will be estimated using a hand-
held global positioning system (GPS) unit.
2.1 In-Situ Soil Characterization Assessment Activities
H&H proposes to conduct soil assessment activities to identify areas at the Site that do not have
compound concentrations in soil above DEQ IHSB Protection of Groundwater and Residential
Use Preliminary Soil Remediation Goals (PSRGs) to assist in export of non-impacted soil during
grading activities.
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Based on discussions with the PD, the project geotechnical engineers, and review of the most
recent version of the grading plans and cut/fill analysis for the Site, H&H understands that
grading and construction activities for the proposed redevelopment will generate up to
approximately 8,000 cubic yards of soil that will likely need to be transported off-Site to achieve
proposed final grade elevations. The export soil volume estimate includes approximately 5,600
cubic yards of geotechnically unsuitable undocumented urban fill that has been identified at
varying depths across the Site. Grading activities at the Site will include undercut in areas of
geotechnically unsuitable soil to depths corresponding to more suitable native soil. A copy of
the most recent grading plan and cut-fill analysis is provided as Appendix A.
There is limited space at the Site for stockpiling export soil during redevelopment activities.
Therefore, to expedite grading activities and to minimize the need to stockpile and manage large
volumes of soil during construction, H&H proposes to conduct soil assessment activities at the
Site to characterize soil in-situ before grading activities begin. The proposed in-situ soil
characterization assessment activities will include collection of soil samples from areas of the
unsuitable fill material as well as areas of proposed cut.
H&H understands that soil may need to be direct loaded onto trucks and transported off-Site
during grading activities. The data collected during the proposed assessment activities outlined
in the following sections will be used to predetermine whether export soil from the proposed
excavations can be transported to a Land Clearing and Inert Debris (LCID) landfill, a
construction and debris (C&D) landfill, a permitted landfill, another Brownfields property for
use as beneficial fill, and/or another suitable location with DEQ approval.
H&H understands that the DEQ Brownfields Program and the DEQ Solid Waste Section will
review results of the soil assessment activities and assist the PD in determining a suitable facility
for the export soil. H&H also understands that the DEQ Solid Waste Section will issue a letter
recommending the type(s) of facilities that could manage the proposed export soil based on soil
characterization laboratory analytical results.
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Proposed cut in western portions of the Site extends to depths ranging from approximately 1 ft to
10 ft bgs. Proposed cut in the eastern portion of the Site extends from approximately 1.5 ft to 4
ft bgs in areas of geotechnically unsuitable soil. H&H divided the Site into twenty-six (26) in-
situ soil characterization sections and proposes to collect soil samples for laboratory analysis in
each soil characterization section to represent material that may need to be exported off-Site.
The in-situ soil characterization sections (denoted by EX nomenclature) are depicted on Figure 3.
H&H will contract with a qualified drilling contractor to advance multiple soil borings in each of
the 26 soil characterization sections (Figure 3). Initially, the drilling contractor will advance
each soil boring with a decontaminated stainless-steel hand auger followed by a track-mounted
direct push technology (DPT) drill rig at depths greater than 5 ft bgs. During boring
advancement, continuous soil samples will be collected from each boring from the center of the
hand auger bucket and/or acetate lined DPT macrocore sleeves. The soil samples will be logged
for lithologic description, inspected for the presence of visual and olfactory indication of
potential impacts, and screened for the presence of volatile organic vapors with a calibrated
photoionization detector (PID).
H&H understands that to obtain approval for export to a non-permitted receiving facility, DEQ
Brownfields and DEQ Solid Waste require an approximate sample frequency of a minimum of
one soil sample for every 500 cubic yards of export soil. Based on review of the cut/fill analysis
and geotechnical reports, and to provide greater vertical and horizontal resolution for the soil
profile in the areas for potential export, H&H assumes that up to thirty-one (31) soil samples will
be needed to adequately characterize soil for export. As appropriate, soil sample aliquots will be
collected from both the urban fill layer (shallow) and native soil layer (deeper) to characterize
soil vertically. Soil samples from each in-situ soil characterization section will be selected for
laboratory analyses as discussed below and as shown in Appendix B.
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Western Portions of the Site
The western portions of the Site generally represent areas of cut at varying depths based on
redevelopment plans and results of geotechnical assessment activities. The western portion of
the Site has been divided into the following in-situ soil characterization sections:
EX-1 and EX-7
Cut in the southwestern portion of the Site will extend to depths up to approximately 10 ft bgs.
The southwestern portion of the Site has been divided into two (2) in-situ soil characterization
sections (EX-1 and EX-7) based on the approximate cut depths in each section. Five (5) soil
borings will be advanced in EX-1 and EX-7 to depths of approximately 10 ft bgs and 8 ft bgs,
respectively (Figure 3).
Multiple soil sample aliquots will be collected from each boring. Shallow and deep EX-1 aliquot
soil samples will be collected at depths of approximately 0 ft to 5 ft bgs and 5 ft to 10 ft bgs,
respectively. Three aliquot soil samples will be collected from EX-7 at depths of approximately
0 ft to 2 ft bgs, 2 ft to 5 ft bgs, and 5 to 8 ft bgs. The soil sample aliquots from each depth
interval will be combined and homogenized to form one composite soil sample representative of
soil conditions in each section at that interval. For example, soil samples selected for laboratory
analysis from section EX-1 will include EX-1 (0-5) and EX-1 (5-10).
EX-3 and EX-4
Planned cut near the western Site boundary will extend to depths up to approximately 5 ft bgs.
This portion of the Site has been divided into two (2) in-situ soil characterization sections (EX-3
and EX-4). Soil borings will be advanced in EX-3 (5 borings) and EX-4 (4 borings) to a depth
of approximately 5 ft bgs (Figure 3).
Results of geotechnical assessment activities identified structurally unsuitable material at shallow
depths in the areas of EX-3 and EX-4. Therefore, shallow soil sample aliquots will be collected
in each section to represent unsuitable soil and deeper soil sample aliquots will be collected to
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represent soil conditions in deeper cut. Aliquot soil samples in EX-3 will be collected at depths
of approximately 0 ft to 2.5 ft bgs and 2.5 ft to 5 ft bgs. Aliquot soil samples in EX-4 will be
collected at depths of approximately 0 ft to 2 ft bgs and 2 ft to 5 ft bgs. The sample aliquots
from each depth interval will be combined and homogenized to form one composite soil sample
representative of soil conditions in each section at that interval. For example, soil samples
selected for laboratory analysis from section EX-3 will include EX-3 (0-2.5) and EX-3 (2.5-5).
EX-5, EX-8, and EX-13
Three in-situ soil characterization sections (EX-5, EX-8, and EX-13) have been established
based on cut depths in these locations that will extend to approximately 4 ft bgs. Five (5) soil
borings in EX-5 and EX-8, and four (4) soil borings in EX-13 will be advanced to a depth of
approximately 4 ft bgs (Figure 3).
Continuous soil sample aliquots will be collected from each of the soil borings advanced in each
soil characterization section. Soil sample aliquots from each boring advanced in a section will be
homogenized to form composite soil samples representative of soil from 0 ft to 4 ft bgs. Soil
samples selected for laboratory analysis will include EX-5 (0-4), EX-8 (0-4), and EX-13 (0-4).
EX-2, EX-10, and EX-11
Three in-situ soil characterization sections (EX-2, EX-10, and EX-11) have been established
based on cut depths in these locations that will extend to approximately 2 ft bgs. Three (3) soil
borings in EX-2 and EX-10, and two (2) soil borings in EX-11 will be advanced to a depth of
approximately 2 ft bgs (Figure 3).
Continuous soil sample aliquots will be collected from each of the soil borings advanced in each
soil characterization section. Soil sample aliquots from each boring advanced in a section will be
homogenized to form composite soil samples representative of soil from 0 ft to 2 ft bgs. Soil
samples selected for laboratory analysis will include EX-2 (0-2), EX-10 (0-2), and EX-11 (0-2).
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EX-9
One in-situ soil characterization section (EX-9) has been established based on proposed cut
depths in this location which will extend to a depth of up to approximately 5 ft bgs. Five (5) soil
borings in EX- 9 will be advanced to a depth of approximately 5 ft bgs (Figure 3).
Continuous soil sample aliquots will be collected from each of the five soil borings. Soil sample
aliquots from each boring will be homogenized to form a composite soil sample representative of
soil from 0 ft to 5 ft bgs. The soil sample for laboratory analysis will therefore be EX-9 (0-5).
EX-12
One in-situ soil characterization section (EX-12) has been established based on proposed cut
depths in this location which will extend to a depth of up to approximately 3 ft bgs. Six (6) soil
borings in EX-12 will be advanced to a depth of approximately 3 ft bgs (Figure 3).
Continuous soil sample aliquots will be collected from each of the six soil borings. Soil sample
aliquots from each boring will be homogenized to form a composite soil sample representative of
soil from 0 ft to 3 ft bgs. The soil sample for laboratory analysis will therefore be EX-12 (0-3).
Eastern Portions of the Site
According to the most recent version of the grading plan, fill will be needed to achieve final
grade elevations in the eastern portion of the Site. However, results of geotechnical assessment
activities identified structurally unsuitable undocumented fill material in shallow soil in several
areas in the eastern portion of the Site that will be undercut to depths corresponding to more
suitable native soil. To characterize the unsuitable material that will be undercut and exported
off-Site, the eastern portions of the Site has been divided into the following in-situ soil
characterization sections:
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EX-6, EX-14 through EX-16, EX-18, EX-20, EX-22, EX-24, and EX-26
The majority of the eastern side of the Site has been divided into in-situ soil characterization
sections with borings to a depth of approximately 3 ft bgs based on proposed cut depths
determined by observed urban fill depths in the vicinity of these locations. Soil borings in each
section will be advanced to a depth of approximately 3 ft bgs (Figure 3). The number of soil
borings in each section will be as follows: five (5) borings in EX-6, EX-14, EX-15, EX-22, and
EX-24; four (4) borings in EX-20 and EX-26; three (3) borings in EX-16; and two (2) borings in
EX-18.
Continuous soil sample aliquots will be collected from each of the soil borings advanced in each
soil characterization section. Soil sample aliquots from each boring advanced in a section will be
homogenized to form composite soil samples representative of soil from 0 ft to 3 ft bgs. Soil
samples selected for laboratory analysis will include EX-6 (0-3), EX-14 (0-3), EX-15 (0-3), etc.
EX-19, EX-21, and EX-25
Three in-situ soil characterization sections (EX-19, EX-21, and EX-25) have been established
based on observed urban fill depths in the vicinity of these locations that extend to depths up to
approximately 4 ft bgs. Three (3) soil borings in EX-19 and EX-25, and four (4) soil borings in
EX-21 will be advanced to a depth of approximately 4 ft bgs (Figure 3).
Continuous soil sample aliquots will be collected from each of the soil borings advanced in each
soil characterization section. Soil sample aliquots from each boring advanced in a section will be
homogenized to form composite soil samples representative of soil from 0 ft to 4 ft bgs. Soil
samples selected for laboratory analysis will include EX-19 (0-4), EX-21 (0-4), and EX-25 (0-4).
EX-17 and EX-23
Two in-situ soil characterization sections (EX-17 and EX-23) have been established based on
observed urban fill depths in the vicinity of these locations that extend to depths no greater than
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2 ft bgs. Four (4) soil borings in EX-17 and three (3) soil borings in EX-23 will be advanced to a
depth of approximately 2 ft bgs (Figure 3).
Continuous soil sample aliquots will be collected from each of the soil borings advanced in each
soil characterization section. Soil sample aliquots from each boring advanced in a section will be
homogenized to form composite soil samples representative of soil from 0 ft to 2 ft bgs. Soil
samples selected for laboratory analysis will include EX-17 (0-2) and EX-23 (0-2).
In-Situ Soil Sample Analyses
The 31 composite soil samples selected for laboratory analyses will be collected directly into
dedicated laboratory supplied sample containers, labeled with the date, time, and sample
identification, and placed in a laboratory supplied sample cooler with ice. The samples will be
submitted to a North Carolina certified laboratory under standard chain of custody protocols for
analysis of semi-volatile organic compounds (SVOCs) by EPA Method 8270 and Resource
Conservation and Recovery Act (RCRA) metals by EPA Methods 6020 and 7471. Samples will
also be collected for potential analysis of hexavalent chromium. Approximately 30% of the
samples indicating the highest concentrations of total chromium will be analyzed for hexavalent
chromium by EPA Method 7199 to speciate the total chromium as either trivalent chromium or
hexavalent chromium. If hexavalent chromium concentrations are identified that exceed the
Residential PSRG, additional soil samples will be analyzed for hexavalent chromium to
determine which in-situ soil characterization sections contain concentrations exceeding the
PSRG.
In addition to the composite soil samples described above, one representative grab soil sample
will be collected from each soil characterization section, at each depth interval represented by a
composite soil sample for a total of 30 grab samples. The grab soil samples will be collected
from undisturbed portions of soil directly into laboratory supplied glassware and submitted to a
North Carolina certified laboratory under standard chain of custody protocols for analysis of
VOCs by EPA Method 8260.
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2.2 Supplemental Vapor Intrusion Assessment Activities
As noted above, results of 2016 vapor intrusion assessment activities completed at the Site
identified low levels of chlorinated solvent and petroleum-related compounds at concentrations
above the DEQ screening criteria in one soil gas sample (VMP-1) collected in the southwestern
portion of the Site. H&H proposes to conduct supplemental soil gas assessment activities at the
Site in areas of proposed retail spaces, proposed ground-floor residential living spaces, and in the
areas of previous 2016 soil gas sample locations to further evaluate the potential for structural
vapor intrusion into the proposed mixed-use buildings.
H&H proposes collection of fourteen (14) soil gas samples within the footprint of proposed
buildings. In accordance with the DEQ DWM VI Guidance, soil gas samples will be collected at
depths greater than 5 ft bgs and at depths above the water table. Based on observations during
2016 assessment activities, it is anticipated that soil gas samples will be collected from depths
ranging from approximately 5.5 ft bgs to approximately 10 ft bgs. Locations of the proposed soil
gas samples are shown in Figure 4.
The soil gas samples will be collected by advancing a soil boring utilizing a decontaminated
stainless-steel hand auger and/or DPT rig. During boring advancement, continuous soil samples
will be collected from each boring from the center of the hand auger bucket or acetate lined
macrocore sleeves. The soil samples will be logged for lithologic description, inspected for the
presence of visual and olfactory indication of potential impacts, and screened for the presence of
volatile organic vapors with a calibrated PID.
A six-inch stainless-steel vapor implant screen point fitted with ¼-inch Teflon tubing will be
placed at the bottom of each borehole. Filter sand will be placed from the base of the boring to
approximately 6-inches above the screened interval. The sampling points will be completed by
placing hydrated bentonite from the top of the filter sand to the ground surface.
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Prior to collection of the samples, a leak check will be conducted at each soil gas sample
location. The leak check will be performed by constructing a shroud around the sampling point,
sampling fittings, and sampling connections, and flooding the air with helium gas. A calibrated
helium gas detector will be used to measure helium concentrations within the shroud during the
leak check. With helium concentrations maintained at near saturated conditions, the sample
tubing will then be purged of a minimum of three volumes outside of the shroud using a syringe
and a three-way valve to collect purged sub-slab vapor into a Tedlar® bag. The purged vapor
will then be analyzed using the helium gas detector to ensure that helium concentrations from the
sample tubing are less than 10% of the helium concentrations measured within the shroud.
Following successful leak checks, the soil gas samples will be collected into 1-Liter Summa
canisters with flow regulators calibrated to collect the sample at a rate not to exceed 200
mL/minute. Once the soil gas samples have been collected, the sample canisters will be labeled
with the date, time, and sample identification, and placed in laboratory supplied shipping
containers. The samples will be submitted to a North Carolina certified laboratory under
standard chain of custody protocols for analysis of VOCs by EPA Method TO-15.
2.3 Quality Assurance/Quality Control
For quality assurance and quality control purposes (QA/QC), one trip blank will be submitted for
laboratory analysis of VOCs by EPA Method 8260 for each soil sample shipment. To evaluate
the reproducibility of the sample results, H&H will collect one duplicate soil and soil gas sample
which will be submitted for the same laboratory analysis as the parent sample. The duplicate soil
gas sample will be collected using a laboratory supplied “T-sample” which allows collection of
two soil gas samples from one sampling point simultaneously. Non-dedicated equipment and
tools will be decontaminated prior to use at each boring or sampling location, or following
exposure to soil.
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Laboratory QA/QC procedures will be employed to ensure appropriate sample handling and
analysis and to aid in the review and validation of the analytical data. QA/QC procedures will be
conducted in accordance with the method protocols and will include regular equipment
maintenance, equipment calibrations, and adherence to specific sample custody and data
management procedures. Samples will be analyzed in conjunction with appropriate blanks,
laboratory duplicates, continuing calibration standards, surrogate standards, and matrix spiking
standards in accordance with approved methodologies to monitor both instrument and analyst
performance. H&H will request that the laboratory reporting limits for each analyte be equal to
or below applicable screening criteria. Additionally, H&H will request that the laboratory
include estimated concentrations for compounds that are detected at levels above the laboratory
method detection limit, but below the laboratory reporting limit (J Flags).
2.4 Reporting
Following completion of the in-situ soil characterization and supplemental vapor intrusion
assessment activities and receipt of the analytical data, H&H will document our findings in a
supplemental Brownfields assessment report. The report will include a description of the
sampling activities, laboratory analytical reports, a tabular summary and discussion of the
laboratory analytical results in comparison to the regulatory screening levels, figures depicting
the sample locations, soil boring logs, soil gas monitoring point construction details, vapor
intrusion risk evaluation, and conclusions concerning our activities. In addition, the DEQ-
approved Environmental Management Plan (EMP) for the Chadbourn Mill Brownfields Property
will be updated to include information specific to the current redevelopment plan which
incorporates the Theron Properties. The updated EMP will be submitted to DEQ Brownfields
for final review and approval.
TITLE
PROJECT
SITE LOCATION MAP
CHADBOURN MILL/THERON PROPERTIES500 & 508 CHARLES AVENUE
CHARLOTTE, NORTH CAROLINA
DATE:
JOB NO:
REVISION NO:
FIGURE:
8-7-2019 0
1CAM-010
SITE
0 2000 4000
APPROXIMATE
SCALE IN FEET
N
U.S.G.S. QUADRANGLE MAP
QUADRANGLE
7.5 MINUTE SERIES (TOPOGRAPHIC)
CHARLOTTE EAST, NC, 1991
REVISION NO. 0
JOB NO. CAM-010
DATE: 8-8-19
FIGURE NO. 2
CHADBOURN MILL/THERON PROPERTIES
500 & 508 CHARLES AVENUE
CHARLOTTE, NORTH CAROLINA
SITE MAP
LEGEND
SITE BOUNDARY
THERON PROPERTIES
UNNAMED CREEK
LYNX BLUE LINE LIGHT RAIL
2923 South Tryon Street-Suite 100
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f)
License # C-1269 / #C-245 Geology
N. B
R
E
V
A
R
D
S
T
R
E
E
T
RESIDENTIAL
DUKE POWER
SUBSTATION
NEESE SAUSAGE COMPANY
(2604 N. DAVIDSON STREET)
JORD
A
N
P
L
A
C
E
CHARL
E
S
A
V
E
N
U
E
N. DAVIDSON STREETMATHESON AVENUE
NOTES:
AERIAL IMAGERY OBTAINED FROM MECKLENBERG COUNTY GIS.
CHARL
E
S
A
V
E
N
U
E
FILLING STATION / AUTO REPAIR
(1950s TO PRESENT)
FORMER BOILER
BUILDING
FORMER CHADBOURN
MILL FACILITY
(PARTIALLY DEMOLISHED)
RESIDENTIAL
REDEVELOPMENT
(UNDER
CONSTRUCTION)
EX-1
EX-2
EX-3
EX-4
EX-5
EX-6
EX-7
EX-8
EX-9
EX-10
EX-11
EX-12
EX-13
EX-14
EX-15
EX-16
EX-17
EX-18
EX-19
EX-20
EX-21
EX-22
EX-23
EX-24
EX-25
EX-26
REVISION NO. 0
JOB NO. CAM-010
DATE: 8-8-19
FIGURE NO. 3
CHADBOURN MILL/THERON PROPERTIES
500 & 508 CHARLES AVENUE
CHARLOTTE, NORTH CAROLINA
PROPOSED SOIL SAMPLE LOCATION MAP
LEGEND
SITE BOUNDARY
THERON PROPERTIES
UNNAMED CREEK
LYNX BLUE LINE LIGHT RAIL
PROPOSED SOIL BORING LOCATION
2923 South Tryon Street-Suite 100
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f)
License # C-1269 / #C-245 Geology
N. B
R
E
V
A
R
D
S
T
R
E
E
T
RESIDENTIAL
DUKE POWER
SUBSTATION
NEESE SAUSAGE COMPANY
(2604 N. DAVIDSON STREET)
JORD
A
N
P
L
A
C
E
CHARL
E
S
A
V
E
N
U
E
N. DAVIDSON STREETMATHESON AVENUE
RESIDENTIAL
REDEVELOPMENT
(UNDER
CONSTRUCTION)
CHARL
E
S
A
V
E
N
U
E
FILLING STATION / AUTO REPAIR
(1950s TO PRESENT)
FORMER CHADBOURN
MILL FACILITY
(PARTIALLY DEMOLISHED)
FORMER BOILER
BUILDING
T
N. DAVIDSON ST.
JORDAN
P
L
A
C
E
17
1
B8.
0
BIK
E
S
T
O
R
A
G
E
8%
8%
8%
8%
8%
701
.
5
0
6%8%8%
ME
Z
Z
A
N
I
N
E
FITN
E
S
S
118
A3.0
_
M
-
H
C
117
A3.0
_
M
168
A3.
6
13
2
B4.0
_
M
113
A1.1
_
S
M
111
A1.
1
_
S
M
109
A1.1
_
S
M
107
A1.
1
_
S
M
104
A1.1
_
S
M
10
6
A1.
1
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S
M
10
8
A1.
1
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S
M
119
A9.0
_
M
116
A9.0
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M
112
A9.
0
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M
141
A1.
1
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S
139
A1.
1
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S
145
A7.
0
148
A1.1
_
S
170
A3.
1
146
A3.
7
150
B1.1
169
A1.
1
_
S
152
A1.
1
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S
15
4
B1.1
16
7
A1.
1
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S
166
B1.0
155
A6.
0
157
A3.
2
156
B1.0
15
8
A1.
0
_
S
160
A3.
0
161
A1.0
_
S
174
A5.0
175
B1.
0
177
B2.0
163
B6.
0
164
A3.
1 162
A3.
1
159
A9.
0
172
A3.
0
-
H
C
173
A3.
0
153
A3.
1
151
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A3.
1
137
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-
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C
110
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0
_
M
115
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M
114
A3.0
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M
102
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70
1
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.
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.
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.
0
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.
0
0
LIFT
CORRI
D
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2
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MECH.
MEC
H
.
CO
R
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D
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EXI
T
P
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A
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E
STA
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3
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R
R
.
IDF
IDF.
MECH.
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R
5
ST
A
I
R
4
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C
H
.
ST
O
R
.
ME
C
H
.
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S
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.
EXH
A
U
S
T
STA
I
R
6
MAI
N
T
E
N
A
N
C
E
BULK
T
R
A
S
H
MAIN E
L
E
C
T
RI
C
A
L
SPR
I
N
K
L
E
R
ST
A
I
R
7
?
CL
U
B
/
L
E
A
S
I
N
G
RET
A
I
L
RE
T
A
I
L
RE
T
.
E
L
E
C
.
ELEC.
EL
E
C
.
EL
E
C
.
DN
DN
UP
5.6
%
S
L
O
P
E
UP5.1% S
L
O
PE
DN
1.1
%
S
L
O
P
E
(
2
%
M
A
X
)
DRY V
AL
V
E
PU
M
P
DO
M
.
PUM
P
FI
R
E
RI
S
E
R
EV
UN
I
T
TY
P
E
A
UNI
T
TYP
E
A
UN
I
T
TY
P
E
A
UNI
T
TYP
E
A
EV
VISI
T
O
R
RE
T
A
I
L
/CC
DN
UP
UP
VA
NCCC
VA
N
VAN
VA
N
VAN
C
C
C
VANTTTIAS-3
IAS-2
SV-03
SV-02
SV-01
VMP-3 VMP-4 VMP-5
VMP-6
VMP-2
VMP-1
IAS-1
SG-1 SSV-1 SSV-2
VMP-7
VMP-8
VMP-9
VMP-10 VMP-11
VMP-12
VMP-13
VMP-14
VMP-15
VMP-16
VMP-17
VMP-18
VMP-19
VMP-20
REVISION NO. 0
JOB NO. CAM-010
DATE: 8-8-19
FIGURE NO. 4
CHADBOURN MILL/THERON PROPERTIES
500 & 508 CHARLES AVENUE
CHARLOTTE, NORTH CAROLINA
PROPOSED SOIL GAS SAMPLE LOCATION MAP
LEGEND
SITE BOUNDARY
THERON PROPERTIES
UNNAMED CREEK
LYNX BLUE LINE LIGHT RAIL
SOIL GAS SAMPLE LOCATION (SEPT. 2016)
SUB-SLAB VAPOR SAMPLE LOCATION (SEPT.
2016)
INDOOR AIR SAMPLE LOCATION (SEPT. 2016)
INDOOR AIR SAMPLE LOCATION (JAN. 2017)
SUB-SLAB SOIL GAS SAMPLE LOCATION (FEB.
2019)
EXTERIOR SOIL GAS SAMPLE LOCATION
(FEB. 2019)
PROPOSED SOIL GAS SAMPLE LOCATION
2923 South Tryon Street-Suite 100
Charlotte, North Carolina 28203
704-586-0007(p) 704-586-0373(f)
License # C-1269 / #C-245 Geology
N. B
R
E
V
A
R
D
S
T
R
E
E
T
RESIDENTIAL
DUKE POWER
SUBSTATION
NEESE SAUSAGE COMPANY
(2604 N. DAVIDSON STREET)
JORD
A
N
P
L
A
C
E
CHARL
E
S
A
V
E
N
U
E
N. DAVIDSON STREETMATHESON AVENUE
CHARL
E
S
A
V
E
N
U
E
FILLING STATION / AUTO REPAIR
(1950s TO PRESENT)
SG-1 SSV-1 SSV-2
FORMER CHADBOURN
MILL FACILITY
(PARTIALLY DEMOLISHED)
FORMER BOILER
BUILDING
RESIDENTIAL
REDEVELOPMENT
(UNDER
CONSTRUCTION)
S:\AAA-Master Projects\Camden - CAM\CAM-010 Camden NoDa Redevelopment\Work Plan\final to DEQ\20086 &
23035_Supplemental Brownfields Assessment Work Plan_Chadbourn Mill-Theron Properties_20190828.doc
Appendix A
Grading Plan and Cut-Fill Analysis
NORTH BREVARD STREETJORDAN PLACE
EAST 28TH STREET
VANCCC VANVANVANVANCCCVANVAN
5.2% SLOPE UP
1.1% SLOPE (2% MAX)DN 5.1% SLOPEUPGARAGE
BIKESTORAGE
STAIR B
STOR.EXHAUST
EXHAUST6
8
8
20
20
RETAIL/VISITORFUTURETENANT
EV TYPE AUNITTYPE AUNITTYPE AUNIT
FUTURETENANT
TYPE AUNIT
MAINTENANCE
702.00
700.00
5
TYPE B HC VAN SPACES ALLOCATED
COILING O.H.
DOOR &
SECURITY GATE
58 UNSECURED SPACES BELOW GATE4 HC RESIDENT SPACES25 RETAIL SPACES29 SHARED SPACES
EV
704.00
SPRINKLER MOVE OUTSTAIR A MAIN
ELECTRICAL
SPRINK.RISER
FIREPUMP
DOM.PUMPDRY VALVELOCATIONDN
DN
DN
DN
DNDNDNDNDN
RETAIL
RETAIL
701.50
703.50
692.50
702.00
700.00
703.50
703.17
702.00
704.00
CLUB/LEASING
FITNESS JOR
D
A
N
P
L
A
C
E N. DAVIDSON ST.TTTT
-0.4 0.2
-6.5
0.5
-3.5
-8.5
-0.5
-1.5
-6.1
-7.9
-1.6
10.5
0.4
-5.5
-7.2
-10.1
3.6
9.3
10.0
0.3
-4.4
-4.1
-4.4
0.1
4.9
-1.9
-3.5
-0.2
-1.3
-3.5
-4.0
-1.9
-1.5
-2.0
-2.6
-3.5
-1.0
-1.4
-1.9
-3.6
-3.7
-4.0
-2.0
-2.3
-2.9
0.3
-1.5
-1.5
-1.7
-2.4
-3.2
-1.6
-1.5
-2.9
-5.2
-3.9
0.5
-2.2
-1.7
-2.0
-2.4
-0.9
-1.5
-4.3
-4.6
-3.8
-3.0
-3.0
-0.7
-1.5
-2.2
-1.9
-2.0
-1.1
-3.8
-4.1
-4.0
-3.8
-2.9
-2.0
-0.8
0.3
0.3
-0.4
-1.8
-2.3
-2.1
-3.3
-3.6
-3.7
5.3
-3.6
-2.8
-1.9
-1.1
0.8
0.9
0.1
-0.8
-2.0
-1.7
-2.3
-2.9
3.3
4.7
5.8
-0.9
-0.4
0.3
0.3
0.9
0.3
0.0
-0.7
-1.0
-1.0
1.7
2.9
4.2
0.1
4.0
1.4
2.2
0.2
0.8
2.1
2.0
0.6
0.3
1.6
2.0
3.0
1.4
4.2
5.0
5.7
0.0
0.9
0.9
2.3
1.9
1.5
2.5
3.9
4.7
4.4
3.4
3.9
5.5
6.0
-0.5
1.0
1.0
2.6
2.1
1.8
3.8
5.0
5.7
6.0
5.9
-0.4
1.1
-2.9
-0.1
1.7
1.1
3.0
2.6
2.5
5.5
6.0
6.0
6.0
6.0
4.9
-2.5
-0.6
1.1
1.9
4.0
4.0
3.8
6.0
6.0
6.0
6.0
6.1
6.9
-0.3
-0.2
0.4
4.0
4.0
4.8
6.0
6.0
6.0
6.0
6.3
-0.8
0.2
3.8
6.0
6.0
5.9
6.0
5.9
-0.7
0.4
3.1
4.8
5.3
5.6
-0.4
0.5
2.5
0.5
5/16/2019 10:26 AM MGRIGSBY N:\_2018\1018414\CAD\CIVIL\7_EARTHWORK.DWG
PN1018414 | 2019.05.06 | CAMDEN CORP.
CHADBOURN MILL ▪ CHARLOTTE, NC ▪ SD EARTHWORK ANALYSIS
Cut/Fill Summary
Name
Design vs. Existing
Strippings Export (8in Depth)
BuildingSlabDepth (12in)
RoadwayDepthMain Entry (12in)
RoadwayDepthCharlesEntry (12in)
RoadwayDepthDavidsonAndJordan (12in)
SidewalkDepth (4in)
Totals
Cut Factor
1.000
1.000
1.000
1.000
1.000
1.000
1.000
Fill Factor
1.150
1.150
1.150
1.150
1.150
1.150
1.150
2d Area
197001.47 Sq. Ft.
190943.86 Sq. Ft.
123888.46 Sq. Ft.
3877.87 Sq. Ft.
1805.13 Sq. Ft.
8030.78 Sq. Ft.
12913.94 Sq. Ft.
538461.50 Sq. Ft.
Cut
8730.90 Cu. Yd.
3536.00 Cu. Yd.
4588.46 Cu. Yd.
100.04 Cu. Yd.
66.14 Cu. Yd.
477.02 Cu. Yd.
238.88 Cu. Yd.
17737.45 Cu. Yd.
Fill
14238.20 Cu. Yd.
0.00 Cu. Yd.
0.00 Cu. Yd.
0.00 Cu. Yd.
0.00 Cu. Yd.
0.00 Cu. Yd.
0.00 Cu. Yd.
14238.20 Cu. Yd.
Net
5507.30 Cu. Yd.<Fill>
3536.00 Cu. Yd.<Cut>
4588.46 Cu. Yd.<Cut>
100.04 Cu. Yd.<Cut>
66.14 Cu. Yd.<Cut>
477.02 Cu. Yd.<Cut>
238.88 Cu. Yd.<Cut>
3499.25 Cu. Yd.<Cut>
S:\AAA-Master Projects\Camden - CAM\CAM-010 Camden NoDa Redevelopment\Work Plan\final to DEQ\20086 &
23035_Supplemental Brownfields Assessment Work Plan_Chadbourn Mill-Theron Properties_20190828.doc
Appendix B
In-Situ Soil Characterization Plan Table
Appendix BSummary of In-Situ Soil Characterization Sampling PlanChadbourn Mill and Theron Properties500 and 508 Charles AvenueCharlotte, North CarolinaH&H Job No. CAM-010Soil Characterization Section IDSample Interval (Feet)Excavation Volume(Cubic Yards)Number of Borings Per Soil Characterization SectionNumber of Samples Per Depth IntervalSoil Laboratory Analysis0‐5 965 15‐10 965 1EX‐2 0‐2 618 3 10‐2.5 691 12.5‐5 691 10‐2 362 12‐5 543 1EX‐5 0‐4 1,048 5 1EX‐6 0‐3 986 5 10‐2 554 12‐5 831 15‐8 831 1EX‐8 0‐4 964 5 1EX‐9 0‐5 1,070 5 1EX‐10 0‐2 648 3 1EX‐11 0‐2 368 2 1EX‐12 0‐3 969 6 1EX‐13 0‐4 772 4 1EX‐14 0‐3 996 5 1EX‐15 0‐3 1,029 5 1EX‐16 0‐3 636 3 1EX‐17 0‐2 872 4 1EX‐18 0‐3 341 2 1EX‐19 0‐4 878 3 1EX‐20 0‐3 733 4 1EX‐21 0‐4 655 4 1EX‐22 0‐3 836 5 1EX‐23 0‐2 471 3 1EX‐24 0‐3 902 5 1EX‐25 0‐4 792 3 1EX‐26 0‐3 670 4 1VOCs = volatile organic compoundsSVOCs = semi‐volatile organic compoundsRCRA = Resource Conservation and Recovery Act (metals include arsenic, barium, cadmium, total chromium, lead, mercury, selenium, silver)* Approximately 30% of the soil samples indicating the highest total chromium concentrations will be analyzed for hexavalent chromium.EX‐1 5VOCs by EPA Method 8260 SVOCs by EPA Method 8270 RCRA metals by EPA Methods 6020/7471 hexavalent chromium by EPA Method 7199* EX‐3 5EX‐4 4EX‐7 5S:\AAA‐Master Projects\Camden ‐ CAM\CAM‐010 Camden NoDa Redevelopment\Work Plan\Table\Composite Sample Volumes_201908268/28/2019Appendix BHart & Hickman, PC