NC0005088_Coal Pile Assessment Tech Memo_20180719

TECHNICAL MEMORANDUM

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Action\Assessment\Coal Pile Assessment\Coal Pile Assessment Workplan\Coal Pile Assessment Tech Memo -
Cliffside.docx
Date: June 29, 2018 File: 1026.21.06O
To: Ryan Czop (Duke Energy)
Cc: Kathy Webb (SynTerra)
From: Scott Spinner
Subject: Soil and Groundwater Assessment – Coal Pile – Cliffside Steam Station
Duke Energy Carolinas, LLC (Duke Energy) owns and operates the Rogers Energy
Complex (henceforth referred to as the Cliffside Steam Station (CSS), or the site), which
is located in Mooresboro, Rutherford and Cleveland Counties, North Carolina. CSS
began operation in 1940 as a coal-fired generating station. Units 1 through 4 were
retired in October 2011, and currently only Units 5 and 6 are in operation at CSS. Coal
used for electricity generation is transported to the Site by railroad and stored on
approximately 22 acres northeast of the the Unit 5 power generation plant and north of
the Unit 6 power generation plant. The coal ash residue and other liquid discharges
from coal combustion processes at CSS have historically been managed in CSS ash
basins, which consist of the active ash basin, the Units 1 -4 inactive ash basin, and the
Unit 5 inactive ash basin. Groundwater and soil assessment activities for the coal
storage area (coal pile) are described herein.
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 impoundment.
Groundwater monitoring wells were not installed near the coal pile during CAMA-
associated fieldwork. Duke Energy understands the soils beneath the coal pile may be a
potential “secondary source” of inorganic constituents that will be assessed apart from
CAMA.
Soil and Groundwater Assessment – Coal Pile June 29, 2018
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Station Description
Coal-fired power generation operations began at CSS in 1940. Coal is transported on-
site by rail and offloaded onto the coal pile area where it is stored until burned by the
coal-powered energy generating units. The coal pile area is approximately 22 acres and
is located northeast of the the Unit 5 power generation plant and north of the Unit 6
power gerneration plant. A liner is located beneath approximately four acres of the
eastern end of the coal pile.
The topography at CSS generally slopes downward from the south to the Broad River
on the north. The site layout is shown on Figure 1.
Coal Pile Area Assessment Objectives
Objectives of the coal pile area assessment include the following:
Characterize inorganic constituents associated with coal pile area soils
Characterize inorganic constituent concentrations in groundwater underlying the
coal pile area perimeter
Compare inorganic constituent concentrations in coal pile area groundwater and
site background groundwater

Soil Assessment
Coal pile area soils are proposed to be sampled and analyzed for inorganic parameters
to determine if the soil may be a secondary source of coal pile constituents that could
leach into underlying groundwater. Soil samples are proposed to be collected at
proposed monitoring well locations (CP-1 through CP-6) as part of well installation
activities (Figure 1). Due to the coal pile being active, soil samples directly beneath the
footprint of the coal pile will not be accessible. Soil samples will be collected at
approximately 5-foot intervals to the top of the groundwater table. An additional
shallow soil sample will be collected below the water table within the new well
screened intervals. Samples of bedrock will not be collected for analysis. Soil samples
will be analyzed for inorganic parameters as listed on Table 1. Soil samples will also be
collected approximately 5-feet below ground surface and the interval immediately
above the water table and analyzed for leachable inorganics using Synthetic
Precipitation Leaching Procedures (SPLP) at each well cluster location.
Groundwater Assessment
Fourteen coal pile assessment (CP) groundwater monitoring wells are proposed to be
installed to characterize coal pile area groundwater. Six shallow (“S”), six deep (“D”),
and two bedrock (“BR”) groundwater monitoring wells (CP-1S/D, CP-2S/D/BR, CP-
Soil and Groundwater Assessment – Coal Pile June 29, 2018
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3S/D, CP-4S/D, CP-5S/D/BR, and CPA-6S/D) are proposed to be installed. Proposed
approximate CP well installation locations are shown on Figure 1 and proposed well
details are provided as Table 2. Shallow groundwater monitoring wells will be installed
approximately 5 feet below the water table. Specific well locations may be shifted
depending upon access and field conditions at the time of installation. Groundwater
samples will be analyzed for inorganic constituents as listed on Table 3. Groundwater
samples from monitoring wells CP-3S/D, CP-4S/D, and CP-5S/D/BR will also be
analyzed for total uranium, radium-226, and radium-228.
Coal Pile Assessment Report
A coal pile assessment report will be prepared once all soil and groundwater sample
analytical data is received following two rounds of groundwater data collection.
Additional existing site data will be used in characterizing the coal pile soils and
groundwater, including CAMA and CCR program data. 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

ATTACHMENTS:
Table 1: Soil Analytical Methods
Table 2: Proposed Coal Pile Assessment Soil Samples and Monitoring Wells
Table 3: Groundwater Analytical Methods
Figure 1: Proposed Coal Pile Assessment Monitoring Well Locations
Soil and Groundwater Assessment – Coal Pile January 12, 2018
Cliffside Steam Station

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ATTACHMENTS

TABLE 1
SOIL ANALYTICAL METHODS
CLIFFSIDE STEAM STATION
DUKE ENERGY CAROLINAS, LLC, MOORESBORO, NC
INORGANIC COMPOUNDS UNITS METHOD
Aluminum mg/kg EPA 6010D
Antimony mg/kg EPA 6020B
Arsenic mg/kg EPA 6020A
Barium mg/kg EPA 6010C
Beryllium mg/kg EPA 6020B
Boron mg/kg EPA 6010C
Cadmium mg/kg EPA 6020A
Calcium mg/kg EPA 6010C
Chloride mg/kg EPA 9056A
Chromium mg/kg EPA 6010C
Cobalt mg/kg EPA 6020A
Copper mg/kg EPA 6010C
Iron mg/kg EPA 6010C
Lead mg/kg EPA 6020A
Magnesium mg/kg EPA 6010C
Manganese mg/kg EPA 6010C
Mercury mg/kg EPA Method 7471B
Molybdenum mg/kg EPA 6010C
Nickel mg/kg EPA 6010C
Nitrate as Nitrogen mg/kg EPA 9056A
pH SU EPA 9045D
Potassium mg/kg EPA 6010C
Selenium mg/kg EPA 6020A
Sodium mg/kg EPA 6010C
Strontium mg/kg EPA 6010C
Sulfate mg/kg EPA 9056A
Thallium (low level) (SPLP Extract only)mg/kg EPA 6020A
Total Organic Carbon mg/kg EPA 9060
Vanadium mg/kg EPA 6020A
Zinc mg/kg EPA 6010C
Notes:
meq/100g - millequivalents per 100 grams
mg/kg - Milligrams per kilogram
mV - Millivolts
S.U. - Standard Unit
Prepared by: RBI Checked by: SRW/TCP
1. Soil samples to be analyzed for Total Inorganics using USEPA Methods 6010/6020 and pH using USEPA Method 9045; 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 at time of CSA field implementation in 2015. Analytical methods and
reporting limits are updated periodically and applied as appropriate.
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Table 1 Soil Analytical Methods Page 1 of 1
TABLE 2
PROPOSED COAL PILE ASSESSMENT SOIL SAMPLES AND MONITORING WELLS
CLIFFSIDE STEAM STATION
DUKE ENERGY CAROLINAS, LLC, MOORESBORO, NC
Monitoring
Well ID
Estimated
Well Depth
(feet bgs)
Soil Sample ID
(Estimated Depth
Interval in feet bgs)
Comments
----CP-1SB (3.5-5)Near-surface unsaturated soil sample (water table ~25 feet bgs)
----CP-1SB (8.5-10)Unsaturated soil sample
----CP-1SB (13.5-15)Unsaturated soil sample
----CP-1SB (18.5-20)Unsaturated soil sample
----CP-1SB (23.5-25)Unsaturated soil sample
CP-1S 40 CP-1SB (33.5-35)Soil sample from shallow well screened interval
CP-1D 60 CP-1SB (53.5-55)Soil sample from deep well screened interval
----CP-2SB (3.5-5)Near-surface unsaturated soil sample (water table ~25 feet bgs)
----CP-2SB (8.5-10)Unsaturated soil sample
----CP-2SB (13.5-15)Unsaturated soil sample
----CP-2SB (18.5-20)Unsaturated soil sample
----CP-2SB (23.5-25)Unsaturated soil sample
CP-2S 40 CP-2SB (33.5-35)Soil sample from shallow well screened interval
CP-2D 60 CP-2SB (53.5-55)Soil sample from deep well screened interval
CP-2BR 130 -No soil samples from this well
----CP-3SB (3.5-5)Near-surface unsaturated soil sample (water table ~25 feet bgs)
----CP-3SB (8.5-10)Unsaturated soil sample
----CP-SB (13.5-15)Unsaturated soil sample
----CP-3SB (18.5-20)Unsaturated soil sample
----CP-3SB (23.5-25)Unsaturated soil sample
CP-3S 40 CP-3SB (33.5-35)Soil sample from shallow well screened interval
CP-3D 60 CP-3SB (53.5-55)Soil sample from deep well screened interval
----CP-4SB (3.5-5)Near-surface unsaturated soil sample (water table ~25 feet bgs)
----CP-4SB (8.5-10)Unsaturated soil sample
----CP-4SB (13.5-15)Unsaturated soil sample
----CP-4SB (18.5-20)Unsaturated soil sample
----CP-4SB (23.5-25)Unsaturated soil sample
CP-4S 40 CP-4SB (33.5-35)Soil sample from shallow well screened interval
CP-4D 60 CP-4SB (53.5-55)Soil sample from deep well screened interval
----CP-5SB (3.5-5)Near-surface unsaturated soil sample (water table ~25 feet bgs)
----CP-5SB (8.5-10)Unsaturated soil sample
----CP-5SB (13.5-15)Unsaturated soil sample
----CP-5SB (18.5-20)Unsaturated soil sample
----CP-5SB (23.5-25)Unsaturated soil sample
CP-5S 40 CP-5SB (33.5-35)Soil sample from shallow well screened interval
CP-5D 60 CP-5SB (53.5-55)Soil sample from deep well screened interval
CP-5BR 130 -No soil samples from this well
----CP-6SB (3.5-5)Near-surface unsaturated soil sample (water table ~25 feet bgs)
----CP-6SB (8.5-10)Unsaturated soil sample
----CP-6SB (13.5-15)Unsaturated soil sample
----CP-6SB (18.5-20)Unsaturated soil sample
----CP-6SB (23.5-25)Unsaturated soil sample
CP-6S 40 CP-6SB (33.5-35)Soil sample from shallow well screened interval
CP-6D 60 CP-6SB (53.5-55)Soil sample from deep well screened interval
Prepared by: SAS Checked by: DMY
Notes:
bgs = below ground surface
~ = Approximately
SynTerra recommends hollow stem auger and air rotary methods for boring and well installation.
Continuous cores from air rotary drilling provide sufficient material for soil sampling and lithologic description.
Estimated well and soil sample depths based on data from the GWA-14 well cluster.
Number 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 the shallow monitoring wells be installed approximately 5 feet below the water table and have a length of at least 10 feet.
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Proposed Coal Pile Assessment Boring & Well Depths Page 1 of 1
TABLE 3
GROUNDWATER ANALYTICAL METHODS
CLIFFSIDE STEAM STATION
DUKE ENERGY CAROLINAS, LLC, MOORESBORO, NC
PARAMETER RL UNITS METHOD
pH NA SU Field Water Quality Meter
Specific Conductance NA µS/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
Eh NA mV Field Water Quality Meter
Turbidity NA NTU Field Water Quality Meter
Aluminum 0.005 mg/L EPA 200.7 or 6010D
Antimony 0.001 mg/L EPA 200.8 or 6020B
Arsenic 0.001 mg/L EPA 200.8 or 6020B
Barium 0.005 mg/L EPA 200.7 or 6010D
Beryllium 0.001 mg/L EPA 200.8 or 6020B
Boron 0.05 mg/L EPA 200.7 or 6010D
Cadmium 0.001 mg/L EPA 200.8 or 6020B
Chromium 0.001 mg/L EPA 200.8 or 6020B
Cobalt 0.001 mg/L EPA 200.8 or 6020B
Copper 0.001 mg/L EPA 200.8 or 6020B
Hexavalent Chromium 0.000025 mg/L EPA 218.7
Iron 0.01 mg/L EPA 200.7 or 6010D
Lithium 1 mg/L EPA 200.7 or 6010D
Lead 0.001 mg/L EPA 200.8 or 6020B
Manganese 0.005 mg/L EPA 200.7 or 6010D
Mercury 0.00005 mg/L EPA 245.1 or 7470A
Molybdenum 0.001 mg/L EPA 200.8 or 6020B
Nickel 0.001 mg/L EPA 200.8 or 6020B
Selenium 0.001 mg/L EPA 200.8 or 6020B
Strontium 0.005 mg/L EPA 200.7 or 6010D
Thallium (low level)0.0002 mg/L EPA 200.8 or 6020B
Vanadium (low level)0.0003 mg/L EPA 200.8 or 6020B
Zinc 0.005 mg/L EPA 200.7 or 6010D
Radium 226 1 pCi/L EPA 903.1 Modified
Radium 228 1 pCi/L EPA 904.0/SW846 9320 Modified
Uranium (233, 234, 236, 238)Varies by isotope µg/mL SW846 3010A/6020A
Alkalinity (as CaCO3)5 mg/L SM 2320B
Bicarbonate 5 mg/L SM 2320B
Calcium 0.01 mg/L EPA 200.7
Carbonate 5 mg/L SM 2320B
Chloride 0.1 mg/L EPA 300.0 or 9056A
Fluoride 0.1 mg/L EPA 300.0 or 9056A
Magnesium 0.005 mg/L EPA 200.7 or 6010D
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 0.1 mg/L SM 4500 S2 D
Total Dissolved Solids 25 mg/L SM 2540C
Total Phosphorus 0.05 mg/L EPA 365.1
Total Organic Carbon 0.1 mg/L SM5310C/EPA9060A
Total Suspended Solids 5 mg/L SM 2450D
Prepared by: HHS Checked by: RHJ
Notes:
NA indicates not applicable.
°C - Degrees Celsius
mg/L - Milligrams per liter
mV - Millivolts
NTU - Nephelometric turbidity unit
pCi/L - picocuries per liter
RL = reporting limit
S.U. - Standard Unit
ug/mL - micrograms per milliliter
µS/cm = micro-Siemens per centimeter
Dissolved and total metals analysis
FIELD PARAMETERS
INORGANICS
RADIONUCLIDES
ANIONS/CATIONS/OTHER
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Table 3 - Groundwater Analytical Methods Page 1 of 1
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GP-3S/D FIGURE 1PROPOSED ADDITIONAL ASSESSMENTMONITORING WELLS - COAL PILE AREACLIFFSIDE STEAM STATIONDUKE ENERGY CAROLINAS, LLCMOORESBORO, NORTH CAROLINADRAWN BY: A. ROBINSONPROJECT MANAGER: S. SPINNERCHECKED BY: M. YOUNGBLOOD
DATE: 02/28/2018
148 RIVER STREET, SUITE 220GREENVILLE, SOUTH CAROLINA 29601PHONE [phone]www.synterracorp.com
P:\Duke Energy Progress.1026\00 GIS BASE DATA\Cliffside\Mapdocs\MISC\CLIFFSIDE_Proposed_Assessment_Coal Pile.mxd
100 0 100 20050
GRAPHIC SCALE IN FEET
UNITS 1-4INACTIVEASH BASIN
BROAD RIVER
LEGEND
!(PROPOSED COAL PILE ASSESSMENT MONITORINGWELL LOCATION
&<EXISTING MONITORING WELL LOCATION
&<EXISTING MONITORING WELL LOCATION (ABANDONED)
TRANSMISSION LINES FROM WSP SURVEY
RAILROAD TRACKS FROM WSP SURVEY
T&E SPECIES FROM AMEC NRTR
INACTIVE ASH BASIN WASTE BOUNDARY
NOTES:
1) IT IS HEREIN NOTED THAT DUKE ENERGY IS NOT WAIVING THE RIGHT TO A COMPLIANCE BOUNDARY(S) TO THE FULL EXTENT SET OUT IN THE LAW OR ATTEMPT TO IMPAIR THE DEPARTMENT'S ABILITY TO CHANGE THE COMPLIANCE BOUNDARY(S) IN THE FUTURE, IF CIRCUMSTANCES W ARRANT.
2) AERIAL PHOTOGRAPHY OBTAINED FROM GOOGLE EARTH PRO AND IS DATED OCTOBER 8, 2016.
UNIT 5
COAL PILESTORAGE AREA