REVISED_Duke_BelewsCreek_CoalPile_Assessment_WorkPlan_20190715

161p
synTerra
COAL PILE AREA ASSESSMENT WORK PLAN
FOR
BELEWS CREEK STEAM STATION
3195 PINE HALL ROAD
BELEWS CREEK, NC 27009
SUBMITTED: MAY 2019
REVISED: DULY 2019
PREPARED FOR
DUKE ENERGY CAROLINAS, LLC
('DUKE
ENERGY
PREPARED BY
SYNTERRA CORPORATION
Ashley A ert, NC LG 2615
Project Manager
J
David Avard
Project Scientist

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
TABLE OF CONTENTS
SECTION
PAGE
1.0 INTRODUCTION.........................................................................................................1-1
1.1 Regulatory Background...........................................................................................1-1
1.2 Site Description.........................................................................................................1-2
2.0 COAL PILE ASSESSMENT OBJECTIVES..............................................................2-1
2.1 Soil Assessment......................................................................................................... 2-1
2.2 Groundwater Assessment....................................................................................... 2-2
3.0 REPORTING..................................................................................................................3-1
LIST OF FIGURES
Figure 1 Proposed Coal Pile Assessment Sample Locations
LIST OF TABLES
Table 1 Proposed Coal Pile Assessment Soil Samples and Monitoring Wells
Table 2 Soil Analytical Parameters
Table 3 Groundwater Analytical Parameters
List of Attachments
Attachment A Coal Pile Area Assessment Work Plan Comments — Belews Creek
Steam Station (June 24, 2019)
Page i

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
1.0 INTRODUCTION
This revised work plan provides a description of groundwater and soil assessment
activities proposed for the Coal Pile area at the Belews Creek Steam Station (BCSS,
Station, or Site), with consideration of comments received by North Carolina
Department of Environmental Quality (NCDEQ) on June 24, 2019 (Attachment A).
BCSS is owned and operated by Duke Energy Carolinas, LLC (Duke Energy). The Site,
located in Stokes County, North Carolina, encompasses approximately 6,100 acres of
company -owned property along Belews Reservoir. The Coal Pile is located east of the
Structural Fill and southeast of the ash basin (Figure 1).
1.1 Regulatory Background
In 2014, The North Carolina General Assembly passed the Coal Ash Management Act
(CAMA). CAMA required owners of a coal combustion residuals (CCR) surface
impoundment to conduct detailed assessment of site groundwater within and around
the CCR surface impoundments. The primary source of CCR-related constituents at the
BCSS was identified as the ash basin during the Comprehensive Site Assessment (CSA)
(HDR, 2015) and the CSA Update (SynTerra, 2017).
The Coal Pile is not coincident with the ash basin, as it is located approximately 1,700
feet southeast of the ash basin and a topographic hydrogeological divide represented by
Pine Hall Road. The topographic hydrogeological divide was identified through Site
assessment information from the CSA and CSA Update. Groundwater flow direction
beneath the Coal Pile is predicted to be predominantly away from the ash basin, and
toward the plant area and Belews Reservoir. Groundwater monitoring well GWA-6S/D
is located approximately 1,000 feet north of the Coal Pile, and GWA-7S/D is located
approximately 500 feet northwest of the Coal Pile (Figure 1). However, these wells are
considered upgradient of the Coal Pile. No existing monitoring wells are located in
areas predicted to be downgradient, in the direction of groundwater flow from the Coal
Pile. Because no groundwater sampling results are currently available for use in
assessing the area, assessment of inorganic constituents in soils and groundwater in the
Coal Pile area is planned.
Duke Energy understands the Coal Pile area groundwater and soils could be primary
and secondary sources of inorganic constituents that are to be further assessed apart
from CAMA or the CCR Rule.
Page 1-1
P:\Duke Energy Carolinas\20. BELEWS CREEK\29.Structural Fill, Coal Pile and Gypsum Pad Assessment\02.Coal
Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
1.2 Site Description
Detailed descriptions of the Site operational history, physical setting and features,
geology/hydrogeology, and results of the findings of Site assessment -related works are
documented in the following documents:
• Comprehensive Site Assessment Report — Belews Creek Steam Station Ash Basin (HDR
Engineering, Inc. of the Carolinas (HDR, 2015a).
• Corrective Action Plan Part 1— Belews Creek Steam Station Ash Basin (HDR, 2015b).
• Corrective Action Plan Part 2 (included CSA Supplement 1 as Appendix A) — Belews
Creek Steam Station Ash Basin (HDR, 2016a).
• Comprehensive Site Assessment Supplement 2 — Belews Creek Steam Station Ash Basin
(HDR, 2016b).
• Comprehensive Site Assessment Update — Belews Creek Steam Station Ash Basin
(SynTerra, 2017).
• 2018 CAMA Annual Interim Monitoring Report —Belews Creek Steam Station
(SynTerra, April 2018).
The Coal Pile is the storage field for coal used in the Station's process for power
generation. The storage field holds about 1,350,000 tons of coal covering an area of
approximately 42 acres. The approximate footprint of the coal pile area is depicted on
Figure 1. The Coal Pile storage field is unlined and has been maintained at the same
location since Station operations began in 1974. The Coal Pile has been identified as a
potential additional source of inorganic constituents in groundwater by NCDEQ.
Page 1-2
P:\Duke Energy Carolinas\20. BELEWS CREEK\29.Structural Fill, Coal Pile and Gypsum Pad Assessment\02.Coal
Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
2.0 COAL PILE ASSESSMENT OBJECTIVES
Objectives of the Coal Pile assessment include the following:
• Characterize unsaturated soil inorganic constituents for assessment of potential
secondary sources to groundwater.
• Determine groundwater flow direction.
• Compare inorganic constituent concentrations in the Coal Pile area with site
background concentrations evaluated during the CAMA ash basin assessment
and with other applicable regulatory criteria.
• Evaluate potential constituent transport.
2.1 Soil Assessment
Coal Pile area soils would be sampled and analyzed for inorganic parameters to
determine whether they are a secondary source of inorganic constituents that can leach
into underlying groundwater. Soil samples would be collected at prescribed depths, as
described on Table 1, from proposed monitoring well locations (Figure 1) as part of
well installation activities. Soil samples would be collected at approximately 2-foot
intervals to the top of the groundwater table. An additional soil sample would be
collected below the water table within the new well screen interval. Soil samples would
be analyzed for inorganic parameters listed on Table 2, with adjusted reporting limits
appropriate for comparison of soil analytical results to the Primary Soil Remediation
Goals Protection of Groundwater (PSRG POG).
Soil samples would also be analyzed using a synthetic precipitation leaching procedure
(SPLP) to understand potential leaching effects from the solid media. Soil SPLP samples
would be collected at a frequency of two per well cluster location with one unsaturated
sample collected from 2 to 3 feet below ground surface, and one saturated sample
collected 2 to 3 feet below the water table. Soil SPLP samples would be analyzed for
inorganic parameters listed on Table 2.
Soil or rock samples would be collected from depths that coincide with the screen
intervals of newly installed wells for potential analysis of metal oxy-hydroxide phases
of iron and aluminum (HFO and HAO). After the first round of groundwater sampling,
wells that are geochemically significant to the Site would be selected for analysis as
necessary.
Page 2-1
P:\Duke Energy Carolinas\20. BELEWS CREEK\29.Structural Fill, Coal Pile and Gypsum Pad Assessment\02.Coal
Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
2.2 Groundwater Assessment
Twenty-four (24) Coal Pile area assessment groundwater monitoring wells (designated
as "CP ") would be installed in shallow, deep, and bedrock groundwater zones in
designated areas surrounding the Coal Pile. Proposed Coal Pile area well installation
locations are shown on Figure 1, and proposed well details are provided as Table 1.
The shallow zone is considered groundwater within soil and unconsolidated saprolite
material. The deep zone is considered groundwater within partially weathered rock,
transition zone material underlying the shallow zone, and overlying competent
bedrock. The bedrock zone is considered competent rock, with potential for bedrock
fractures. Eight shallow ("S"), eight deep ("D"), and eight bedrock ("BR") groundwater
monitoring wells (CP-1S/D/BR through CP-8S/D/BR) would be installed as well clusters
surrounding the Coal Pile. Specific well locations may be shifted depending on access
and field conditions at the time of installation.
Well installation procedures and well construction materials and lengths would be
consistent with ongoing CAMA assessment activities in accordance with the approved
Proposed Groundwater Assessment Work Plan (Rev. 1) (SynTerra, 2014). During boring
installation, soil/rock cuttings would be described for lithologic information, including
color and soil/rock type. Each well would be constructed in accordance with NCAC
Title 15A, Subchapter 2C, Section .0100 Well Construction Standards and consist of 2-
inch diameter NSF schedule 40 PVC flush -joint threaded casings and prepacked
screens.
After installation, the monitoring wells would be developed in order to remove drill
fluids, clay, silt, sand, and other fines, which might have been introduced into the
formation or sand pack during drilling and well installation, and to establish
communication of the well with the aquifer. After well completion, the newly installed
wells would be surveyed for location and elevation.
Groundwater samples would be collected using low -flow sampling techniques per the
groundwater sampling procedures provided in the Low Flow Sampling Plan, Duke Energy
Facilities, Ash Basin Groundwater Assessment Program, North Carolina, June 10, 2015 (Low
Flow Sampling Plan). Groundwater samples will be analyzed for constituent parameters
in Table 3.
Water levels would be collected within a 24-hour time frame. Data would be used for
depicting water elevation contours and determining groundwater flow directions. Slug
testing would be performed for each groundwater monitoring well installed to evaluate
Page 2-2
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Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
hydraulic conductivity of each flow zone. Horizontal and vertical gradients and
groundwater velocity would be calculated.
Page 2-3
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Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
3.0 REPORTING
The Coal Pile assessment findings would be presented in a CSA report that would be
submitted to the NCDEQ Division of Water Resources (DWR) on March 31, 2020, as
requested in an April 5, 2019, letter to Duke Energy. The report will include the
following components:
1) Site History and Source Characterization
2) Site Geology and Hydrogeology
3) Sampling Results
4) Site Conceptual Model
5) Conclusions and Recommendations
Page 3-1
P:\Duke Energy Carolinas\20. BELEWS CREEK\29.Structural Fill, Coal Pile and Gypsum Pad Assessment\02.Coal
Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
Figures
P:\Duke Energy Carolinas\20. BELEWS CREEK\29.Structural Fill, Coal Pile and Gypsum Pad Assessment\02.Coal
Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

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FIGURE 1
PROPOSED COAL PILE
ASSESSMENT SAMPLE LOCATIONS
BELEWS CREEK STEAM STATION
DRAWN BY: B.YOUNG DATE:05/09/2019
REVISED BY: B. YOUNG DATE: 07/12/2019
o
Terra
synwww.synterracorp.com
CHECKED BY: A. ALBERT DATE: 07/12/2019
APPROVED BY: A. ALBERT DATE: 07/12/2019
PROJECT MANAGER: A. ALBERT
BELEWS CREEK, NORTH CAROLINA

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
Tables
P:\Duke Energy Carolinas\20. BELEWS CREEK\29.Structural Fill, Coal Pile and Gypsum Pad Assessment\02.Coal
Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

TABLE 1
PROPOSED COAL PILE AREA ASSESSMENT SOIL SAMPLES AND MONITORING WELLS
BELEWS CREEK STEAM STATION
DUKE ENERGY CAROLINAS, LLC, BELEWS CREEK NC
Monitoring
Well ID
Estimated
Well Depth
(feet bgs)l
Soil Sample ID
(Estimated Depth
Interval in feet bgs)Z
Preferred Drilling Method 3
Comments°
CP-1SB (2-4)
Near -surface unsaturated soil sample, water table —10 feet bgs
CP-1SB (5-7)
Unsaturated soil sample, water table —10 feet bgs
CP-1SB (8-10)
Unsaturated to partially saturated soil sample, water table —10 feet bgs
CP-1S
30
CP-1SB (20-30)
Hollow -Stem Auger
Soil sample from shallow well screened interval and HAO/HFO sample
CP-1D
60
CP-1SB 50-60
Hollow -Stem Auger/Air Rotary or Sonic
Soil/partially weathered rock sample from deep well screened interval and HAO/HFO sample
CP-113R
100
CP-1SB (90-100)
Hollow -Stem Auger/Air Rotary or Sonic
Rock sample from bedrock well screened interval and HAO/HFO sample
CP-2SB (2-4)
Near -surface unsaturated soil sample, water table —10 feet bgs
CP-2SB (5-7)
Unsaturated soil sample, water table —10 feet bgs
CP-2SB (8-10)
Unsaturated to partially saturated soil sample, water table —10 feet bgs
CP-2S
30
CP-2SB (20-30)
Hollow -Stem Auger
Soil sample from shallow well screened interval and HAO/HFO sample
CP-21)
60
CP-2SB (50-60)
Hollow -Stem Auger/Air Rotary or Sonic
Soil/partially weathered rock sample from deep well screened interval and HAO/HFO sample
CP-2BR
100
CP-2SB 90-100
Hollow -Stem Auger/Air Rotary or Sonic
Rock sample from bedrock well screened interval and HAO/HFO sample
CP-3SB (2-4)
Near -surface unsaturated soil sample, water table —10 feet bgs
CP-3SB (5-7)
Unsaturated soil sample, water table —10 feet bgs
CP-3SB (8-10)
Unsaturated to partially saturated soil sample, water table —10 feet bgs
CP-3S
30
CP-3SB (20-30)
Hollow -Stem Auger
Soil sample from shallow well screened interval and HAO/HFO sample
CP-3D
60
CP-3SB 50-60
Hollow -Stem Auqer/Air Rotary or Sonic
Soil/partially weathered rock sample from deep well screened interval and HAO/HFO sample
CP-3BR
100
CP-3SB 90-100
Hollow -Stem Auger/Air Rotary or Sonic
Rock sample from bedrock well screened interval and HAO/HFO sample
CP-4SB 2-4
Near -surface unsaturated soil sample, water table —10 feet bgs
CP-4SB (5-7)
Unsaturated soil sample, water table —10 feet bgs
CP-4SB (8-10)
Unsaturated to partially saturated soil sample, water table —10 feet bgs
CP-4S
30
CP-4SB 20-30
Hollow -Stem Auger
Soil sample from shallow well screened interval and HAO/HFO sample
CP-4D
60
CP-4SB 50-60
Hollow -Stem Auqer/Air Rotary or Sonic
Soil/partially weathered rock sample from deep well screened interval and HAO/HFO sample
CP-4BR
100
CP-4SB 90-100
Hollow -Stem Auger/Air Rotary or Sonic
Rock sample from bedrock well screened interval and HAO/HFO sample
CP-5SB (2-4)
Near -surface unsaturated soil sample, water table —10 feet bgs
CP-5SB (5-7)
Unsaturated soil sample, water table —10 feet bgs
CP-5SB 8-10
Unsaturated to partially saturated soil sample, water table —10 feet bgs
CP-5S
30
CP-5SB 20-30
Hollow -Stem Auger
Soil sample from shallow well screened interval and HAO/HFO sample
CP-5D
60
CP-5SB 50-60
Hollow -Stem Auqer/Air Rotary or Sonic
Soil/partially weathered rock sample from deep well screened interval and HAO/HFO sample
CP-513R
100
CP-5SB (90-100)
Hollow -Stem Auger/Air Rotary or Sonic
Rock sample from bedrock well screened interval and HAO/HFO sample
P:\Duke Energy Progress. 1026\_ADMINISTRATIVE\Financial Management\Project Change Requests (PCRs)\Belews Creek\Proposal 14235 - Structural Fill, Coal Pile and Gypsum Pad Assessment Page 1 of 2

TABLE 1
PROPOSED COAL PILE AREA ASSESSMENT SOIL SAMPLES AND MONITORING WELLS
BELEWS CREEK STEAM STATION
DUKE ENERGY CAROLINAS, LLC, BELEWS CREEK NC
Monitoring
Well ID
Estimated
Well Depth
(feet bgs)l
Soil Sample ID
(Estimated Depth
Interval in feet bgs)Z
Preferred Drilling Method'
Comments°
CP-6SB (2-4)
Near -surface unsaturated soil sample, water table —10 feet bgs
CP-6SB 5-7
Unsaturated soil sample, water table —10 feet bgs
CP-6SB 8-10
Unsaturated to partially saturated soil sample, water table —10 feet bgs
CP-6S
30
CP-6SB 20-30
Hollow -Stem Auger
Soil sample from shallow well screened interval and HAO/HFO sample
CP-6D
60
CP-6SB (50-60)
Hollow -Stem Auger/Air Rotary or Sonic
Soil/partially weathered rock sample from deep well screened interval and HAO/HFO sample
CP-6BR
100
CP-6SB (90-100)
Hollow -Stem Auger/Air Rotary or Sonic
Rock sample from bedrock well screened interval and HAO/HFO sample
CP-7SB (2-4)
Near -surface unsaturated soil sample, water table —10 feet bgs
CP-7SB (5-7)
Unsaturated soil sample, water table —10 feet bgs
CP-7SB (8-10)
Unsaturated to partially saturated soil sample, water table —10 feet bgs
CP-7S
30
CP-7SB (20-30)
Hollow -Stem Auger
Soil sample from shallow well screened interval and HAO/HFO sample
CP-7D
60
CP-7SB (50-60)
Hollow -Stem Auger/Air Rotary or Sonic
Soil/partially weathered rock sample from deep well screened interval and HAO/HFO sample
CP-7BR
100
CP-7SB (90-100)
Hollow -Stem Auger/Air Rotary or Sonic
Rock sample from bedrock well screened interval and HAO/HFO sample
CP-8SB (2-4)
Near -surface unsaturated soil sample, water table —10 feet bgs
CP-8SB (5-7)
Unsaturated soil sample, water table —10 feet bgs
CP-8SB (8-10)
Unsaturated to partially saturated soil sample, water table —10 feet bgs
CP-8S
30
CP-8SB (20-30)
Hollow -Stem Auger
Soil sample from shallow well screened interval and HAO/HFO sample
CP-8D
60
CP-8SB (50-60)
Hollow -Stem Auger/Air Rotary or Sonic
Soil/partially weathered rock sample from deep well screened interval and HAO/HFO sample
CP-8BR
100
CP-8SB (90-100)
Hollow -Stem Auger/Air Rotary or Sonic
Rock sample from bedrock well screened interval and HAO/HFO sample
Prepared by: ALA Checked by: COE
Notes:
bgs = below ground surface
— = Approximately
HAO = Hydrous aluminum Oxide
HFO = Hydrous ferric oxides
'Proposed boring depths and screened intervals are estimates based on well construction information from nearest spatitally existing wells; actual screened intervals and total boring depths will be determined based on field
observations and approved by a INC Licensed Geologist. SynTerra recommends each well screen be submerged beneath the water table and have a length of at least 10 feet
2Number of soil samples shown is approximate. A shallower water table will result in fewer samples, and a deeper water table will result in additional samples.
'SynTerra recommends a combination of hollow stem auger and air rotary or sonic drilling methods for boring and well installation
°Soil sample for inorganic analysis and HAO/HFO sample collection by means of split spoon techniques within the open borehole provide sufficient material for soil sampling and lithologic description. SynTerra recommends each
well screen be submerged beneath the water table and have a length of at least 10 feet
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TABLE 2
SOIL ANALYTICAL PARAMETERS
BELEWS CREEK STEAM STATION
DUKE ENERGY CAROLINAS, LLC, BELEWS CREEK, NC
INORGANIC COMPOUNDS
PSRG POG
UNITS
METHOD
Aluminum
110000
mg/kg
EPA 6010D
Antimony
0.9
mg/kg
EPA 6020B
Arsenic
5.8
mg/kg
EPA 6020B
Barium
580
mg/kg
EPA 6010D
Beryllium
63
mg/kg
EPA 6020B
Boron
45
mg/kg
EPA 6010D
Cadmium
3
mg/kg
EPA 6020B
Calcium
NE
mg/kg
EPA 6010D
Chloride*
NE
mg/kg
EPA 9056A
Chromium
3.8
mg/kg
EPA 6010D
Cobalt
0.9
mg/kg
EPA 6020B
Copper
700
mg/kg
EPA 6010D
Iron
150
mg/kg
EPA 6010D
Lead
270
mg/kg
EPA 6020B
Magnesium
NE
mg/kg
EPA 6010D
Manganese
65
mg/kg
EPA 6010D
Mercury
1
mg/kg
EPA 7471B or 7470A
Molybdenum
7.1
mg/kg
EPA 6010D
Nickel
130
mg/kg
EPA 6010D
Nitrate as Nitrogen*
NE
mg/kg
EPA 9056A
pH*
NE
S.U.
EPA 9045D
Potassium
NE
mg/kg
EPA 6010D
Selenium
2.1
mg/kg
EPA 6020B
Sodium
NE
mg/kg
EPA 6010D
Strontium
1500
mg/kg
EPA 6010D
Sulfate*
NE
mg/kg
EPA 9056A
Thallium low level
0.28
mg/kq
EPA 6020B
Total Organic Carbon*
NE
mg/kg
EPA 9060A
Vanadium
350
mg/kg
EPA 6020B
Zinc
1200
mg/kg
EPA 6010D
Prepared by: RBI Checked by: CJS
Notes:
1. Soil samples to be analyzed for Total Inorganics using USEPA Methods 6010/6020 and pH using USEPA Method 9045, as
noted above. Select soil samples will also be analyzed for leaching potential using SPLP Extraction Method 1312 in
conjunction with USEPA Methods 6010/6020.
2. Analytical methods and reporting limits as presented were applicable as of May 6, 2019. Analytical methods and reporting
limits are updated periodically and applied as appropriate.
*Select constituents are not analyzed for leaching potential.
PSRG POG - Primary Soil Remediation Goals Protection of Groundwater
mg/kg - Milligrams per kilogram
S.U. - Standard Unit
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Assessment\Tables\Table 2 - Soil Analytical Parameters Page 1 of 1

TABLE 3
GROUNDWATER ANALYTICAL PARAMETERS
BELEWS CREEK STEAM STATION
DUKE ENERGY CAROLINAS, LLC, BELEWS CREEK, NC
PARAMETER
RL
UNITS
METHOD
FIELD PARAMETERS
pH
NA
SU
Field Water Quality Meter
Specific Conductance
NA
PS/cm
Field Water Quality Meter
Oxidation/Reduction Potential
NA
mV
Field Water Quality Meter
Temperature
NA
oC
Field Water Quality Meter
Eh
NA
mV
Field Water Quality Meter and Calculation
Dissolved Oxygen
NA
mg/L
Field Water Quality Meter
Turbidity
NA
NTU
Field Water Quality Meter
INORGANICS (total and dissolved)
Aluminum
5
pg/L
EPA 200.7
Antimony
1
µ /L
EPA 200.8
Arsenic
1
ug/L
EPA 200.8
Barium
5
/L
EPA 200.7
Beryllium
1
µg/L
EPA 200.8
Boron
50
/L
EPA 200.7
Cadmium
0.1
ug/L
EPA 200.8
Chromium
1
/L
EPA 200.8
Chromium (VI)
0.025
ug/L
EPA 218.7
Cobalt
1
/L
EPA 200.8
Copper
1
ug/L
EPA 200.8
Iron
10
/L
EPA 200.7
Lead
1
ug/L
EPA 200.8
Lithium
2.5
/L
EPA 200.8
Manganese
5
µg/L
EPA 200.7
Mercury
0.00005
m /L
EPA 245.1 or 7470A
Molybdenum
1
µg/L
EPA 200.8
Nickel
1
/L
EPA 200.8
Phosphorus
0.0005
Ug/L
EPA 365.1
Selenium
1
/L
EPA 200.8
Silver
0.3
Ug/L
EPA 200.8
Strontium
5
/L
EPA 200.7
Thallium (low level)
0.2
Ug/L
EPA 200.8
Vanadium low level
0.3
/L
EPA 200.8
Zinc
5
L
EPA 200.7
RADIONUCLIDES
Radium 226
1
Ci/L
EPA 903.1 Modified
Radium 228
1
pCi/L
EPA 904.0/SW846 9320 Modified
Uranium 233 234 236 238
Varies by isotope
mL
SW846 3010A 6020A
ANIONS/CATIONS/OTHER
Alkalinity (as CaCO3)
5
mg/L
SM 2320B
Bicarbonate
5
mg/L
SM 2320E
Calcium
0.01
mg/L
EPA 200.7
Carbonate
5
mg/L
SM 2320E
Chloride
0.1
mg/L
EPA 300.0
Fluoride
0.1
mg/L
EPA 300.0
Magnesium
0.005
mg/L
EPA 200.7
Nitrate + Nitrite
0.01
m -N/L
EPA 353.2
Potassium
0.1
mg/L
EPA 200.7
Sodium
0.05
m /L
EPA 200.7
Sulfate
0.1
mg/L
EPA 300.0
Sulfide
0.1
m /L
SM 4500-S2D
Total Dissolved Solids
25
mg/L
SM 2540C
Total Organic Carbon
0.1
m /L
SM53106/EPA9060A
Total Suspended Solids
2.5
m L
SM 2540D
Prepared by: REB Checked by: KHG
Notes:
OC - Degrees Celsius
VS/cm - micro -Siemens per centimeter
µg/L - Micrograms per liter
µg/mL - Micrograms per milliliter
RL - Reporting limit
mg - N/L - Milligrams nitrogen per liter
mg/L - Milligrams per liter
mV - Millivolts
NA - not applicable
NTU - Nephelometric turbidity unit
pCi/L - Picocuries per liter
S.U. - Standard Unit
PADuke Energy Carolinas\20. BELEWS CREEK\29.Structural Fill, Coal Pile and Gypsum Pad Assessment\02.Coal Pile Groundwater
Assessment\Tables\Table 3 - Groundwater Analytical Parameters Page 1 of 1

Coal Pile Area Assessment Work Plan Submitted May 2019; Revised July 2019
Duke Energy Carolinas, LLC — Belews Creek Steam Station SynTerra
Attachment A
P:\Duke Energy Carolinas\20. BELEWS CREEK\29.Structural Fill, Coal Pile and Gypsum Pad Assessment\02.Coal
Pile Groundwater Assessment\Belews Creek - Coal Pile Assessment Work Plan.docx

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
LINDA CULPEPPER
Director
Paul Draovitch
Senior Vice President
Environmental, Health & Safety
Duke Energy
526 South Church Street
Mail Code EC3XP
Charlotte, North Carolina 28202
NORTH CAROLINA
Envfronmenta! Qualtty
June 24, 2019
Subject: Coal Pile Area Assessment Work Plan Comments — Belews Creek Steam Station
Dear Mr. Draovitch:
On May 24, 2019, the North Carolina Department of Environmental Quality Division of Water
Resources (Division) received the proposed Coal Pile Area Assessment Work Plan for the Belews
Creek Steam Station. The Division has reviewed and hereby approves the proposed assessment
activities under the condition that the following items are addressed as part of the plan
implementation and the results reported in the comprehensive site assessment concerning the
subject area.
• Add a well cluster (shallow/deep/bedrock) immediately adjacent to and downgradient of
the coal pile to assess potential impacts within the footprint of the storage field.
• Please update Table 2 to reflect the additional wells requested.
• Please add a line outlining the footprint of the coal pile on Figure 1 and clearly label any
related features.
• Surface water samples should be collected in Belews Reservoir east of proposed well
cluster CP-4S/D/BR.
• In addition to further characterizing groundwater flow regimes in the vicinity of the coal
pile storage field, data should be collected from each proposed well to evaluate hydraulic
parameters such as hydraulic conductivity and flow velocity in the area.
If applicable, the results should also be incorporated into the updated CAP's revised geochemical
and groundwater fate and transport models. If the results of the modeling show current or future
impacts to groundwater and/or surface water from this area, then appropriate remedial strategies
shall be proposed in the CAP.
North Carolina Department of Environmental Quality I Division of Water Resources
0 I 512 North Salisbury Street 1 1636 Mail Service Center I Raleigh, North Carolina 27699-1636
919.707.9000

If you have any questions, please contact Shuying Wang (Winston-Salem Regional Office) at
[phone] or Steve Lanter (Central Office) at [phone].
Sincere
Jon Risga Chief
Animal Feeding Operations and Groundwater Section
cc: WSRO WQROS Regional Office
WQROS Central File Copy