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HomeMy WebLinkAboutMarshall Additional Source Area Work Plan - REV 2L7 synTerra TECHNICAL MEMORANDUM Date: September 17, 2019 - REV 2 File: 1026.18.26 December 07, 2018 - REV 1 Original Submitted November 30, 2018 To: Tyler Hardin (Duke Energy) Cc: Kathy Webb; Walter Ger Id (SynTerra) From: Brian Wilker, P.G. Subject: Marshall Steam Station - Additional Source Areas Assessment Work Plan - REV 2 INTRODUCTION Duke Energy Carolinas, LLC (Duke Energy) owns and operates the Marshall Steam Station in Terrell, Catawba County, North Carolina. The Site encompasses approximately 1,446 acres. The initial technical memorandum describing groundwater and soil assessment activities for the Marshall Steam Station (MSS, Plant, or Site) additional source areas (e.g., coal pile) was submitted to the North Carolina Department of Environmental Quality (NCDEQ) Mooresville Regional Office (MRO) on November 30, 2018. In correspondence dated December 03, 2018, NCDEQ MRO conditionally approved the planned assessment activities. A revised Work Plan (REV 1), incorporating MRO comments, was filed on December 07, 2018 (Attachment 1). The purpose of this technical memorandum is to propose one additional bedrock monitoring well for vertical delineation east of the coal pile as request by NCDEQ MRO (Figure 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. Primary sources of CCR-related constituents were identified during the Comprehensive Site Assessment (CSA). Duke Energy received a letter on September 8, 2018, from the NCDEQ Division of Water Resources regarding assessment of groundwater impacts from other potential primary and secondary sources other than the CCR surface impoundment (e.g., coal pile and gypsum pad). Groundwater monitoring wells were installed downgradient (east) of the coal pile and gypsum pad areas. Additionally, wells were installed for compliance with the Environmental Protection Agency's CCR P: \ Duke Energy Carolinas \ 18. MARSHALL \ 20.Addt'1 Source Area Assessment Drilling Oversight \ Work Plan \REV. 2 - Sept. 16 2019 \ Marshall Additional Source Area Work Plan - REV 2.docx Additional Source Area Assessment Work Plan (REV 2) September 17, 2019 Duke Energy Carolinas, LLC, Marshall Steam Station SynTerra Rule along the perimeter of the coal pile area. Boron, an inorganic constituent, is commonly used as an indicator of CCR impacts to groundwater. Groundwater sampling results from the CP-1 well cluster installed on the northeastern corner of the coal pile indicated elevated concentrations of boron and other constituents related to coal handling activities. For vertical delineation of constituents at this location, Duke Energy proposes to install one bedrock well at the CP-1 well cluster (CP-1BR). STATION DESCRIPTION Coal-fired power generation began at MSS in 1965 and remains active. Coal used for electricity generation is transported to the Site by railroad and stored on approximately 35 acres north of the power generation plant (coal pile). The topography and corresponding potentiometric surface at the Site generally slope downward from the northwest to the southeast toward Lake Norman. Slight variations in localized groundwater flow direction may exist, but flow is predominantly northwest to southeast. ADDITIONAL SOURCE AREA ASSESSMENT OBJECTIVES Objectives of the additional source area assessment include the following: • Characterization of inorganic constituent concentrations in bedrock groundwater at the northeastern corner of the coal pile area (CP-1 location). • Comparison of inorganic constituent concentrations associated with the coal pile/ash basin bedrock groundwater with Site background concentrations and applicable regulatory standards. GROUNDWATER ASSESSMENT In March 2019, six (6) coal pile (CP) assessment groundwater monitoring wells were installed to characterize the coal pile groundwater in shallow and deep groundwater zones. In September 2019, NCDEQ MRO requested installation of one (1) additional groundwater monitoring well (CP-1BR) located at CP-1 well cluster to assess the groundwater within the bedrock zone at the coal pile area. The bedrock zone is considered groundwater within competent bedrock, which flows through secondary porosity provided by fractures. Proposed additional CP-1BR well installation location is shown on Figure 1 and proposed well details are provided in Table 1. Specific well locations may be shifted depending upon access and field conditions at the time of installation. Groundwater samples from the proposed well will be analyzed for the full suite of CAMA parameters for at least four quarters, as specified in the Interim Monitoring Plan (IMP). P: \ Duke Energy Carolinas \ 18. MARSHALL \ 20.Addt'1 Source Area Assessment Drilling Oversight \ Work Plan \REV. 2 - Sept. 16 2019 \ Marshall Additional Source Area Work Plan - REV 2.docx Additional Source Area Assessment Work Plan (REV 2) September 17, 2019 Duke Energy Carolinas, LLC, Marshall Steam Station SynTerra ATTACHMENTS Figure 1 Proposed Monitoring Well Location Table 1 Proposed Monitoring Well Details Attachment 1 Additional Source Areas Evaluation Work Plan — REV 1 P: \ Duke Energy Carolinas \ 18. MARSHALL \ 20.Addt'l Source Area Assessment Drilling Oversight \ Work Plan\REV. 2 - Sept. 16 2019\Marshall Additional Source Area Work Plan - REV 2.docx Additional Source Area Assessment Work Plan (REV 2) September 17, 2019 Duke Energy Carolinas, LLC, Marshall Steam Station ATTACHMENTS SynTerra P: \ Duke Energy Carolinas \ 18. MARSHALL \ 20.Addt'l Source Area Assessment Drilling Oversight \ Work Plan\REV. 2 - Sept. 16 2019\Marshall Additional Source Area Work Plan - REV 2.docx . j 1 i r • r♦ �y of yd'• r• ^F r �► a = ` 4 ti ' r � ♦ yy��,, a ASH LANDFILL,, Ilk (PHASE 11) AN ll� Iwo got • �i ,�y.• _ ` FT•. ° ru �� ° ' ,ems '} i ....� •� 1 r .. 1 .• ; S ,I.�, J•` - -fir, - ♦���� Y'! I''1,. i 1, 0 P. ail =i± * NN6*Ld L . A LEGEND � •� ' ..�, _ �,.. �.: � PROPOSED MONITORING WELL '+ or _ �� A ASH BASIN WASTE BOUNDARY i I �k - J '� ,+,, �- ,•' - - - - -ASH BASIN COMPLIANCE BOUNDARY ' . £' �' �' �• LANDFILL BOUNDARY It - STRUCTURAL FILL BOUNDARY LANDFILL COMPLIANCE BOUNDARY kiw I +� 1 I y • — - - 'DUKE ENERGY BOUNDARY MARSHALL PLANT f: SITE 4 I STREAM FROM MCKIM & CREED h ,� ,�' Fy - � � - � _ }} � WETLAND FROM MCKIM &CREED �� A a — • 3n): TRANSMISSION LINES FROM WSP SURVEY r - �� . RAILROAD TRACKS FROM WSP SURVEY _ - - $ ,•,� 1 - .f NOTES: �:. � r NATURAL RESOURCES TECHNICAL REPORT (NRTR) PREPARED BYAMEC FOSTER WHEELER, INC., JUNE 19, 2015. a w WETLAND DELINEATION SURVEY CONDUCTED BY MCKIM AND CREED, MARCH 2O16. �- � e � � - �''�y F • � f PROPERTY BOUNDARY PROVIDED BY DUKE ENERGY CAROLINAS. • �' ni +� fin= 1 "y"y M1 1 AERIAL PHOTOGRAPHY OBTAINED FROM GOOGLE EARTH PRO ON JULY 26, 2018. r- 1,_ _ _+.p _ - - • - IMAGE COLLECTED ON MARCH 30, 2018. +• DRAWING HAS BEEN SET WITH A PROJECTION OF NORTH CAROLINA STATE PLANE r� x ► ? `.` r COORDINATE SYSTEM RIPS 3200 (NAD83). ♦ i.;� . - _ �' DUDE soo o soo soo FIGURE 1 S •�� �• ■� �' •• � ENERGY GRAPHIC SCALE IN FEET CAROLINAS 148 RIVER STREET, SUITE 220 PROPOSED MONITORING WELL LOCATION GREENVILLE, SOUTH CAROLINA 29601 MARSHALL STEAM STATION PHONE w.svn6rracor9999 DUKE ENERGY CAROLINAS, LLC _ www.s nterracor .com DRAWN BY: C. WYATT DATE: 09/17/2019 - F c►mTorra CHECKEDBYNAAGER:KBRWILKER TERRELL, NORTH CAROLINA TABLE 1 PROPOSED MONITORING WELL DETAILS MARSHALL STEAM STATION DUKE ENERGY CAROLINAS, LLC, TERRELL, NC Proposed Screen Initial Purpose Well ID Interval' Comments (ft bgs) Coal Pile Area Estimated depths based on CP-1 cluster CP-iBR 140-150 Assessment boring logs Notes: 1 Proposed screened intervals are estimated based on nearby borings/wells that have been previously installed and are subject to change based on field observations. P:\Duke Energy Carolinas\18. MARS HALL\20.Addt'I Source Area Assessment Drilling Oversight\Work Plan\REV. 2 - Sept. 16 2019\ Table 1 Source Area Assessment Wells.xlsx Page 1 of 1 L� synTerra TECHNICAL MEMORANDUM Date: December 7, 2018 (REV 1) File: 1026.18 To: Tyler Hardin (Duke Energy) Cc: Kathy Webb (SynTerra) From: Brian Wilker, P.G. �;J— Subject: Marshall Steam Station Additional Source Areas Assessment Work Plan Introduction Duke Energy Carolinas, LLC (Duke Energy) owns and operates the Marshall Steam Station (MSS or Site) in Terrell, North Carolina. MSS, which encompasses approximately 1,446 acres, began operation as a coal-fired electricity -generating facility in 1965. The Plant currently contains four active coal combustion units. Coal used for electricity generation is transported to the Site by railroad and stored on approximately 35 acres north of the power generation plant (coal pile). Gypsum, a byproduct of the coal combustion process, is stored on approximately 3.5 acres west of the coal pile (Figure 1). Groundwater and soil assessment activities proposed for the coal pile and the gypsum storage area 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 surrounding the CCR surface impoundment. During the CAMA Comprehensive Site Assessment (CSA), a source of CCR-related constituents in groundwater and soil at the Site was identified as the ash contained within the ash basin. Groundwater monitoring wells were installed east of the coal pile (GWA-1 cluster) and gypsum pad area (GWA-2 cluster) during CAMA-associated fieldwork. Additionally, for compliance with the Environmental Protection Agency's Coal Combustion Residuals (CCR) Rule, wells were installed along the perimeter (north and east) of the coal pile area (CCR-1, CCR-2, and CCR-3 clusters). In a letter dated September 8, 2017, the North Carolina Department of Environmental Quality (NCDEQ) Division of Water Resources provided Duke Energy technical direction regarding the assessment and corrective action for additional sources at coal ash facilities. The letter reiterated the rules and requirements outlined in Title 15A North Carolina Administrative Code (NCAC) Subchapter 02L (02L), which requires P: \ Duke Energy Carolinas \ 18. MARSHALL \ Additional Source Areas \ Marshall Additional Source Area Assessment TM.docx Additional Source Areas Assessment Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station Page 2 of 5 Duke Energy to address groundwater impacts from other potential primary and secondary sources other than the CCR surface impoundment. For this reason, Duke Energy understands soils and underlying groundwater at the coal pile area and at the gypsum storage area to be additional potential sources of inorganic constituents that will be assessed apart from CAMA. Station Description Coal-fired power generation began at MSS in 1965 and remains active. CCR have been, and continue to be, sluiced to the ash basin system located north of the power generation plant. It is anticipated that sluicing operations will cease in 2019. Coal used to fuel power -generating units is transported to the Site by railroad and is stored on approximately 35 acres north of the power -generation plant and south of the ash basin. Gypsum, a coal combustion byproduct, is stored on an approximately 3.5-acre lined concrete pad west of the coal pile area (Figure 1). The topography and corresponding potentiometric surface at the Site generally slopes downward from the northwest to the southeast toward Lake Norman. The Site layout is shown on Figure 1. Additional Source Area Assessment Objectives Objectives of the additional source area assessments include: • Characterization of inorganic constituents associated with soils at and near the coal pile and soils at the gypsum storage area • Characterization of inorganic constituent concentrations in shallow and deep groundwater along the perimeters of the coal pile and gypsum storage area • Comparison of inorganic constituent concentrations in soil and groundwater related to source areas with background concentrations Soil Assessment Unsaturated soils in the potential source areas will be sampled and analyzed for inorganic parameters to determine whether they are a secondary source of constituents that can leach into underlying groundwater. Soil samples will be collected from six locations proposed for the installation of monitoring wells (Figure 1). Three locations are proposed for the coal pile area, and three locations are proposed for the gypsum pad area (Table 1). Soil samples will be collected at approximately 2-foot intervals from ground surface to the top of the groundwater table [approximately 10 feet to 12 feet below ground surface (bgs)] at proposed locations surrounding the coal pile (Table 1). Soil samples will be P: \ Duke Energy Carolinas \ 18. MARSHALL \ Additional Source Areas \ Marshall Additional Source Area Assessment TM.docx Additional Source Areas Assessment Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station Page 3 of 5 collected at approximately 5-foot intervals from ground surface to the top of the groundwater table (approximately 25 feet to 30 feet bgs) at proposed locations surrounding the gypsum storage area (Table 1). An additional soil sample will be collected below the water table within the new shallow (S) and deep (D) well screen intervals at each location. Soil samples will be analyzed for inorganic parameters listed on Table 2. Where applicable, soil samples collected from surficial zones (2 feet to 3 feet bgs) and immediately above the water table will also be analyzed using synthetic precipitation leaching procedure (SPLP) for leaching potential. Sonic drilling is recommended as the method of installation for the secondary source area assessment wells due to the quality of continuous cores produced for subsurface characterization purposes. The boreholes will be properly flushed to remove fluids and cuttings prior to the installation of the monitoring wells. As recommended by the North Carolina Department of Environmental Quality (NCDEQ), Duke/SynTerra will consult closely with drillers to use appropriately -sized filter packs and screens. Continuous soil cores will be collected from the ground surface to the top of bedrock and will serve three purposes: • Document the underlying stratigraphy. • Identify the depth where the transition zone is encountered, the thickness of the transition zone, and where the transition zone well will be screened. • Collect soil samples from a depth corresponding approximately with the middle of the well screens of shallow and deep zone wells. Groundwater Assessment Six groundwater monitoring wells that would be used to characterize groundwater in the shallow and deep groundwater flow zones in the coal pile area ("CP") are proposed for installation (Figure 1; Table 1). Groundwater in soil and saprolite material is considered to be in the shallow flow zone. Groundwater within partially weathered rock or transition zone material underlying the shallow zone and overlying competent bedrock is considered to be in the deep flow zone. Wells will be installed as clusters (CP-1S/D through CP-3S/D). It is proposed that each of those clusters would consist of one shallow ("S") and one deep ("D") groundwater monitoring well as conditions allow. The total number of wells installed at each location may vary depending on conditions encountered during drilling activities (i.e. insufficient transition zone thickness for a well screen). P: \ Duke Energy Carolinas \ 18. MARSHALL \ Additional Source Areas \ Marshall Additional Source Area Assessment TM.docx Additional Source Areas Assessment Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station Page 4 of 5 Six groundwater monitoring wells that would be used to characterize groundwater in the shallow and deep groundwater flow zones in the gypsum storage area ("GP") are proposed for installation (Figure 1; Table 1). Wells will be installed as clusters (GP- 1S/D through GP-3S/D). It is proposed that each of those clusters would consist of one shallow ("S") and one deep ("D") groundwater monitoring well as conditions allow. Existing well clusters in the vicinity of the coal pile and gypsum pad will also be sampled for the additional source areas groundwater characterization. These clusters include GWA-1S/D, GWA-2S/D, CCR-1S/D, CCR-2S/D, and CCR-3S/D. Additional proposed well installation details are provided on Table 1. Specific well locations may be shifted depending on access and field conditions at the time of installation. Groundwater samples will be analyzed for inorganic constituents listed on Table 3. Additional Source Areas Assessment Results Due to the potential plumes from the coal pile and gypsum pad being coincident with the ash basin, results of the additional source areas assessment activities will be provided in the Corrective Action Plan (CAP) anticipated for submittal in December 2019. It is anticipated that soil data and two rounds of groundwater sample analytical data will be part of the data evaluation in the CAP. Conclusions based on data evaluation would also be provided. ATTACHMENTS: Figure 1 Proposed Additional Source Area Assessment Locations Table 1 Proposed Additional Source Area Monitoring Wells Table 2 Soil Analytical Methods Table 3 Groundwater Analytical Methods P: \ Duke Energy Carolinas \ 18. MARSHALL \ Additional Source Areas \ Marshall Additional Source Area Assessment TM.docx Additional Source Areas Assessment Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station ATTACHMENTS P: \ Duke Energy Carolinas \ 18. MARSHALL \ Additional Source Areas \ Marshall Additional Source Area Assessment TM.docx TABLE 1 PROPOSED ADDITIONAL SOURCE AREA MONITORING WELLS MARSHALL STEAM STATION DUKE ENERGY CAROLINAS, LLC, TERRELL, NC Initial Purpose Well ID Proposed Screen Interval' (ft bgs) Comments 2 Coal Pile Area Assessment CP-1S 10-20 Estimated depths based on CCR-2 cluster boring logs CP-1D 40-50 CP-2S 30-40 Estimated depths based on CCR-1 cluster boring logs CP-2D 80-90 CP-3S 30-40 CP-3D 80-90 Gypsum Storage Area Assessment GP -IS 25-35 Estimated depths based on GWA-2 cluster boring logs GP -ID 70-80 GP-2S 25-35 GP-2D 70-80 GP-3S 25-35 GP-3D 70-80 Notes• 1 Proposed screened intervals are estimated based on nearby borings/wells that have been previously installed and are subject to change based on field observations. Z Stratigraphy characterization and sub -surface soil sampling is best accomplished for the anticipated subsuface conditions at the site by use of rotosonic drilling methods. P:\Duke Energy Carolinas\18. MARS HALL\Additional Source Areas\ Table 1 Source Area Assessment Wells Page 1 of 1 TABLE 2 SOIL ANALYTICAL METHODS MARSHALL STEAM STATION DUKE ENERGY CAROLINAS, LLC, TERRELL, NC INORGANIC COMPOUNDS UNITS METHOD Aluminum mg/kg EPA 6010D Antimony mg/kg EPA 6020B Arsenic mg/kg EPA 6020B Barium mg/kg EPA 6010D Beryllium mg/kg EPA 6010D Boron mg/kg EPA 6010D Cadmium mg/kg EPA 6020B Calcium mg/kg EPA 6010D 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 6020B Magnesium mg/kg EPA 6010D Manganese mg/kg EPA 6010C Mercury mg/kg EPA 7471 B Molybdenum mg/kg EPA 6010D Nickel mg/kg EPA 6010C Nitrate as Nitrogen mg/kg EPA 9056A pH SU EPA 9045D Potassium mg/kg EPA 6010D Selenium mg/kg EPA 6020B Sodium mg/kg EPA 6010D Strontium mg/kg EPA 6010D Sulfate mg/kg EPA 9056A Thallium (total, low level) mg/kg EPA 6020B Total Organic Carbon mg/kg EPA 9060 Vanadium mg/kg EPA 6020B Zinc mg/kq EPA 6010C Prepared by: RBI Checked by: WJW 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. Select soil samples will also be analyzed for leaching potential using SPLP Extraction Method 1312 in conjunction with USEPA Methods 6010/6020. 3. 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. meq/100g - millequivalents per 100 grams mg/kg - Milligrams per kilogram my - Millivolts S.U. - Standard Unit P:\Duke Energy Carolinas\18. MARS HALL\Additional Source Areas\ Table 2 Soil Analytical Methods Page 1 of 1 TABLE 3 GROUNDWATER ANALYTICAL METHODS MARSHALL STEAM STATION DUKE ENERGY CAROLINAS, LLC, TERRELL, NC PARAMETER RL UNITS METHOD FIELD PARAMETERS H NA SU Field Water Quality Meter Specific Conductance NA µS/cm Field Water Quality Meter Temperature NA 0C Field Water Quality Meter Dissolved Oxygen NA m /L Field Water Quality Meter Oxidation Reduction Potential NA mV I Field Water Quality Meter Turbidity NA NTU I Field Water Quality Meter Ferrous Iron NA mg /L IField Test Kit INORGANICS Aluminum 0.005 m /L EPA 200.7 or 6010D Antimony 0.001 m /L EPA 200.8 or 6020B Arsenic 0.001 m /L EPA 200.8 or 6020A Barium 0.005 m /L EPA 200.7 or 6010C Beryllium 0.001 m /L EPA 200.8 or 6020A Boron 0.05 m /L EPA 200.7 or 6010C Cadmium 0.001 m L EPA 200.8 or 6020A Chromium 0.001 m L EPA 200.8 or 6010C Cobalt 0.001 m /L EPA 200.8 or 6020A Copper 0.001 m /L EPA 200.8 or 6020B Iron 0.01 m /L EPA 200.7 or 6010C Lead 0.001 m /L EPA 200.8 or 6020A Manganese 0.005 m /L EPA 200.7 or 6010C Mercury low level 0.005 n /L 1631 ONLY Molybdenum 0.001 m /L EPA 200.8 or 6020B Nickel 0.001 m /L EPA 200.8 or 6020B Phosphorus 0.005 m /L EPA 365.1 Selenium 0.001 m /L EPA 200.8 or 6020A Strontium 0.005 m /L EPA 200.7 or 6010C Thallium low level 0.0002 m /L EPA 200.8 or 6020A Vanadium low level 0.0003 m L I EPA 200.8 or 6020A Zinc 0.005 m L EPA 200.7 or 6010C RADIONUCLIDES Radium 226 1 Ci/L EPA 903.1 Modified Radium 228 1 Ci/L EPA 904.0/SW846 9320 Modified Uranium 233, 234, 236, 238 Varies by isotope µg/mL SW846 3010A/6020A ANIONS/CATIONS Alkalinity as CaCO3 5 m /L SM 2320B Bicarbonate 5 m /L SM 2320 Calcium 0.01 m /L EPA 200.7 Carbonate 5 m /L SM 2320 Chloride 0.1 m /L EPA 300.0 or 9056A Magnesium 0.005 m /L EPA 200.7 Methane 0.01 m /L RSK 175 Nitrate as Nitrogen 0.01 m -N/L EPA 353.2 Potassium 0.1 m /L EPA 200.7 Sodium 0.05 mg/L EPA 200.7 Sulfate 0.1 m L EPA 300.0 or 9056A Sulfide 0.1 mg/L SM4500S2-D Total Dissolved Solids 25 m L SM 2540C Total Organic Carbon 0.1 m L SM 5310C EPA9060A Total Suspended Solids 1 2.5 m L ISM 2450D Prepared by: RBI Checked by: WJW Notes• 1. Select constituents will be analyzed for total and dissolved concentrations. 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. OC - Degrees Celsius µS/cm = micro -Siemens per centimeter mg/L - Milligrams per liter mg - N/L - Milligrams nitrogen per liter my - Millivolts NA - Not analyzed NTU - Nephelometric turbidity unit pCi/L - picocuries per liter RL = reporting limit S.U. - Standard Unit ug/mL - micrograms per milliliter P:\Duke Energy Carolinas\18. MARSHALL\Additional Source Areas\Table 3 - GW Analytical Methods Page 1 of 1