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HomeMy WebLinkAboutMarshall Data Gap Evaluation Work Plan REV 2Lip synTerra TECHNICAL MEMORANDUM Date: September 17, 2019 - REV 2 File: 1026.18.06N December 07, 2018 - REV 1 Original Submitted November 15, 2018 To: Tyler Hardin (Duke Energy) Cc: Kathy Webb; Walter Ger Id (SynTerra) From: Brian Wilker, P.G. Subject: Marshall Steam Station - Data Gap Evaluation Work Plan - REV 2 INTRODUCTION The initial technical memorandum describing groundwater and soil assessment activities for the Marshall Steam Station (MSS, Plant, or Site) data gap evaluation was submitted to the North Carolina Department of Environmental Quality (NCDEQ) Mooresville Regional Office (MRO) on November 15, 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). 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. One additional bedrock groundwater monitoring well is proposed for vertical delineation east of the PV structural fill, as requested by the NCDEQ MRO, at existing well cluster PVSF-2 (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 at the Site were identified during the Comprehensive Site Assessment (CSA). Boron, an inorganic constituent, is commonly used as an indicator of CCR impacts to groundwater. Groundwater sampling results from the PVSF-2 well cluster installed downgradient (east) of the PV structural fill indicated elevated concentrations of boron. For vertical delineation of constituents at this location, Duke Energy proposes to install a deeper bedrock well at the PVSF-2 well cluster (PVSF-2BRL). P:\Duke Energy Carolinas\18. MARSHALL\21.Data Gap Evaluation Drilling Oversight\Data Gap Work Plan\REV 2 - Sept 2019\Marshall Data Gap Evaluation Work Plan REV 2.DOCX Data Gap Evaluation Work Plan (REV 2) September 17, 2019 Duke Energy Carolinas, LLC, Marshall Steam Station STATION DESCRIPTION SynTerra Coal-fired power generation began at MSS in 1965 and remains active. CCR at the facility is now dry -handled. The Site contains several ash management areas, most of which are closed landfills under corresponding NCDEQ Solid Waste Section permits. 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. DATA GAP EVALUATION OBJECTIVES Objectives of this revision to the data gap evaluation include the following: • Characterization of inorganic constituent concentrations in bedrock groundwater with depth along the downgradient (east) perimeter of the PV structural fill at existing well cluster PVSF-2. • Comparison of inorganic constituent concentrations associated with the PV structural fill/ash basin bedrock groundwater at PVSF-2 with Site background concentrations and applicable regulatory standards. GROUNDWATER ASSESSMENT In March 2019, nine (9) PV structural fill (PVSF) assessment groundwater monitoring wells were installed to characterize the PV structural fill groundwater in shallow, deep, and bedrock groundwater zones. Three (3) additional wells were installed in July 2019. In September 2019, NCDEQ requested installation of one (1) additional groundwater monitoring well (PVSF-2BRL) located at PVSF-2 well cluster to assess the groundwater within the bedrock zone at the PVSF area. The bedrock zone is considered groundwater within competent bedrock. The proposed additional PVSF-2BRL well 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). ATTACHMENTS Figure 1 Proposed Monitoring Well Location Table 1 Proposed Monitoring Well Details Attachment 1 Data Gap Evaluation Work Plan - REV 1 P:\Duke Energy Carolinas\18. MARSHALL\21.Data Gap Evaluation Drilling Oversight\Data Gap Work Plan\REV 2 - Sept 2019\Marshall Data Gap Evaluation Work Plan REV 2.DOCX Data Gap Evaluation Work Plan (REV 2) September 17, 2019 Duke Energy Carolinas, LLC, Marshall Steam Station ATTACHMENTS SynTerra P:\Duke Energy Carolinas\18. MARSHALL\21.Data Gap Evaluation Drilling Oversight\Data Gap Work Plan\REV 2 - Sept 2019 \ Marshall Data Gap Evaluation Work Plan REV 2.DOCX 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) Estimated depths based on PVSF-2 PV Structural Fill PVSF-2BRL 190-200 cluster 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\21.Data Gap Evaluation Drilling Oversight\Data Gap Work Plan\REV 2 - Sept 2019\ Table 1 Proposed Data Gap Evaluation Locations.xlsx Page 1 of 1 1610 synTerra TECHNICAL MEMORANDUM Date: December 07, 2018 (REV 1) File: 1026.18.06N To: Tyler Hardin (Duke Energy) Cc: Kathy Webb (SynTerra) From: Brian Wilker, P.G. ��J_ Subject: Data Gap Evaluation Work Plan — Marshall Steam Station Introduction Duke Energy Carolinas, LLC (Duke Energy) owns and operates the Marshall Steam Station (MSS, Plant, or Site) in Terrell, North Carolina. The 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. The MSS ash basin, located north of the Plant, contains ash generated from the historic and active coal combustion at the Site (Figure 1). Fly ash and bottom ash were sluiced to the ash basin from approximately 1965 until 1984. Fly ash precipitated from flue gas and bottom ash collected in the bottom of the boilers were sluiced to the ash basin using conveyance water withdrawn from Lake Norman. Since 1984, fly ash has mainly been disposed of in the on -Site Dry Ash Landfills and the sluicing of bottom ash to the ash basin has continued. In addition to the on -Site Dry Ash Landfills, a Structural Fill (also known as the PV Structural Fill) consisting of fly ash and bottom ash was constructed under the structural fill rules found in 15A NCAC 13B .1700 et seq. (Reference No. CCB0031), as well as Duke Energy's Distribution of Residuals Solids Permit issued by the former North Carolina Department of Environment and Natural Resources (NCDENR) Division of Water Quality (DWQ). The PV Structural Fill is located adjacent to, and partially on top of, the northwest portion of the ash basin and is unlined (Figure 1). The Industrial Landfill No. 1 (ILF) (NCDEQ Permit No. 1812-INDUS-2008) is located adjacent to the north portion of the ash basin (Figure 1). The subgrade for portions of this landfill were constructed of fly ash under the structural fill rules found in 15A NCAC 13B .1700 et seq. (Reference No. CCB0072). The landfill was constructed over portions of residual material and over portions of the unlined ash basin. Groundwater and soil assessment activities proposed for these potential additional source areas, other than the ash basin, are described herein. P: \ Duke Energy Carolinas \ 18. MARSHALL \ 06.EHS CAMA Compliance Support \ 06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\REV 1- Dec 7 2018\Marshall Data Gap Evaluation TM - REV Ldocx Data Gap Evaluation Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station Page 2 of 5 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), the primary source of CCR- related constituents in groundwater and soil at the Site was identified as the ash contained within the ash basin. One well cluster (AB-20S/D) was installed through the PV Structural Fill during CAMA-associated fieldwork. Other groundwater monitoring wells were installed west (GWA-4S/D) and south (AB-17S/D) of the ILF during the CAMA field activities. Two existing wells (MW-4/D), located off the southeast corner of the ILF, were used in the National Pollutant Discharge Elimination System (NPDES) groundwater monitoring network, which is no longer active. Because of boron's mobility, it is commonly used as an indicator of CCR effects on groundwater. Boron concentrations detected in ash pore water within the PV Structural Fill at AB-20S are elevated (78,900 µg/L in August 2018). Additionally, CAMA assessment data indicated several constituents of interest identified in the updated CAMA CSA (e.g. cobalt and strontium) in groundwater samples at concentrations uncharacteristic of Site background groundwater. Potential groundwater effects from the PV Structural Fill and ILF subgrade Structural Fill would eventually coincide with the known groundwater plume from the ash basin. Therefore, these areas are being evaluated as data gaps under CAMA regulation. Station Description Coal-fired power generation began at MSS in 1965 and remains active. CCRs have been, and continue to be, sluiced to the ash basin system located north of the power generation plant. Sluicing operations are anticipated to cease in 2019. The Site contains several ash management areas, most of which are closed landfills under corresponding NCDEQ Solid Waste Section permits. The ash basin and ILF remain active ash management areas at the Site. Active sluicing, which contributes to free-standing water within the ash basin, is controlled downgradient by the ash basin dam and the NPDES outfall/discharge to Lake Norman (east side of ash basin). 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. The Site layout is shown on Figure 1. P: \ Duke Energy Carolinas \ 18. MARSHALL \ 06.EHS CAMA Compliance Support \ 06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\REV 1- Dec 7 2018\Marshall Data Gap Evaluation TM - REV l.docx Data Gap Evaluation Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station Page 3 of 5 Data Gap Evaluation Objectives Objectives of the data gap evaluations include: • Characterization of inorganic constituents associated with the PV Structural Fill and ILF subgrade Structural Fill area soils • Characterization of inorganic constituent concentrations in shallow, deep, and bedrock groundwater along the downgradient perimeters of the PV Structural Fill and ILF subgrade Structural Fill area • Comparison of inorganic constituent concentrations associated with the PV Structural Fill and ILF subgrade Structural Fill areas soil and groundwater with Site background concentrations Soil Assessment Soils will be sampled and analyzed for inorganic parameters to determine whether they are a potential secondary source of constituents that can leach into underlying groundwater. Soil samples will be collected from five locations proposed for monitoring well installations (Figure 1). Three locations are proposed for the PV Structural Fill area and two locations are proposed for the ILF subgrade Structural Fill (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 15 feet below ground surface (bgs)] at proposed locations around the PV Structural Fill (Table 1). Soil samples will be collected at approximately 5-foot intervals from ground surface to the top of the groundwater table (approximately 40 feet bgs) at proposed locations around the ILF subgrade Structural Fill (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. The quality of continuous cores produced for subsurface characterization purposes is of high importance; therefore, sonic drilling is recommended as the method of installation for the data gap evaluation wells. The boreholes will be properly flushed to remove fluids and cuttings prior to the installation of the monitoring wells. As recommended by NCDEQ, Duke/SynTerra will consult closely with drillers to use appropriately sized P: \ Duke Energy Carolinas \ 18. MARSHALL \ 06.EHS CAMA Compliance Support \ 06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\REV 1- Dec 7 2018\Marshall Data Gap Evaluation TM - REV l.docx Data Gap Evaluation Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station Page 4 of 5 filter packs and screens. Continuous soil cores, collected from the ground surface to the top of bedrock, will serve these purposes: • Document the underlying stratigraphy. • Identify the depth where the water table and transition zone are encountered, and the thickness of the transition zone. • Facilitate well construction design. • Collect samples from a depth corresponding approximately with the middle of the well screens of shallow and deep zone wells. Groundwater Assessment Nine groundwater monitoring wells that would be used to characterize groundwater in the shallow, deep, and bedrock groundwater flow zones along the downgradient (eastern) perimeter of the PV Structural Fill (Figure 1; Table 1) are proposed for installation. 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. The bedrock flow zone is considered competent bedrock with occasional water -producing fractures, typically encountered within the top 50 feet of competent rock. Wells will be installed as clusters (PVSF-1S/D/BR through PVSF- 3S/D/BR). It is proposed that each of those clusters would consist of one shallow (S), one deep (D), and one bedrock (BR) 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). Five groundwater monitoring wells that would be used to characterize groundwater in the shallow, deep, and bedrock groundwater flow zones near the ILF subgrade Structural Fill (Figure 1; Table 1) are proposed for installation. One well cluster (ILF- 1S/D/BR) downgradient (south) of the ILF is proposed. That well cluster would serve as a replacement for the AB-17 well cluster (the abandonment of which is expected in Q4 2018 or Q12019). As requested by the NCDEQ Mooresville Regional Office (MRO), one well cluster (ILF-2S/D) north of the ILF is proposed. 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. P: \ Duke Energy Carolinas \ 18. MARSHALL \ 06.EHS CAMA Compliance Support \ 06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\REV 1- Dec 7 2018\Marshall Data Gap Evaluation TM - REV Ldocx Data Gap Evaluation Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station Page 5 of 5 Data Gap Evaluation Results Results of the data gap evaluation activities will be provided in the Corrective Action Plan (CAP) report. 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 Data Gap Evaluation Locations Table 1 Proposed Data Gap Evaluation Locations Table 2 Soil Analytical Methods Table 3 Groundwater Analytical Methods P: \ Duke Energy Carolinas \ 18. MARSHALL \ 06.EHS CAMA Compliance Support \ 06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\REV 1- Dec 7 2018\Marshall Data Gap Evaluation TM - REV l.docx Data Gap Evaluation Work Plan — REV 1 December 7, 2018 Duke Energy Carolinas, LLC - Marshall Steam Station ATTACHMENTS P: \ Duke Energy Carolinas \ 18. MARSHALL \ 06.EHS CAMA Compliance Support \ 06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\REV 1- Dec 7 2018\Marshall Data Gap Evaluation TM - REV l.docx v ILF-2S/D INDUSTRIAL LANDFILL #1 ff4ii ILF-1S/D/BR I • - 7':v i PVSF-3SIDIBR �.� { � 2 • PVSF-2S/DIBR L- r1-9Tr;VT47T; Mu I � _ = 4,l:1r • � .� tom. 1 - ti R '.� �. ;ay�tpy4:��I� _ �l x� • .' :p .Y � - - -�' �i� _ins •'.Y[."• PVSF-lS/D/BR �0P • � t * � � - 1Y. r r _ ... � 'i �.;' h'�•''< , j�;��1�� ter{ I r r!I'�f`y„!.� r w ♦, 1 _'. r ,� d. tiA r-1 Vy• �.r ..r, AL �a _ _� �� LEGEND �,, O PROPOSED MONITORING WELL / ' ' l SOIL SAMPLING LOCATION EXISTING MONITORING WELL �" '; '� •---• ASH BASIN WASTE BOUNDARY • I %•• m�`'"' . �°� `-�°'�� — - — - ASH BASIN COMPLIANCE BOUNDARY #10 LANDFILL BOUNDARY i STRUCTURAL FILL BOUNDARY ' • `,f.rY `.. LANDFILL COMPLIANCE BOUNDARY DUKE ENERGY CAROLINAS MARSHALL PLANT �r - �♦ ,�, sasA SITE BOUNDARY ♦ �d. ..—♦1 �• ♦♦ � ♦�• ,►'� _ _ a _-';.'�:.:•, - 11®K, NOTES: "• � i:' -' `• PROPOSED WELL LOCATION SHOWN ARE APPROXIMATED. EXACT WELL LOCATIONS S -r' WILL BE DETERMINED BASED ON ACCESS AND FIELD CONDITIONS AT THE TIME OF 7 WELL INSTALLATION. PROPERTY BOUNDARY PROVIDED BY DUKE ENERGY CAROLINAS. AERIAL PHOTOGRAPHY OBTAINED FROM GOOGLE EARTH PRO ON JULY 26, 2018. .a ` 1 • ..:�/ -IMAGE COLLECTED ON MATCH 30, 2018. 1 � , ,ter � �� '�, •..0 ♦ fr;,' r , ' i, , Hfi t`- DRAWING HAS BEEN SET WITH A PROJECTION OF NORTH CAROLINA STATE PLANE :K = ♦ / l ` +' COORDINATE SYSTEM FIPS 3200 (NAD83/2011). 600 300 0 600 1,200 FIGURE 1 ♦• „, GRAPHIC SCALE IN FEET PROPOSED DATA GAP EVALUATION LOCATIONS synTerra 148 RIVER STREET, SUITE 220 MARSHALL STEAM STATION GREENVILLE, SOUTH CAROLINA 29601 �' '4's 'µ•:. /'i.�•- PHONE 864421-9999 DUKE ENERGY CAROLINAS, LLC A< ' www.s n rr r m `• `DUKE'Po ' �� DRAWN BY: B. YOUNG DATE: 12/07/2018 TERRELL, NORTH CAROLINA ENERGY ' ' - - o ' r•� �,, ♦ / PROJECT MANAGER: B. WICKER ' ` ♦ CAROLINAS CHECKED BY: B. WICKER - ♦ P:\Duke Enerav Pro ress.1026\00 GIB BASE DATA\Marshall\Ma docs\MISC\Fi 01 - DataGap Pro osedWells 20181105.mxd TABLE 1 PROPOSED DATA GAP EVALUATION LOCATIONS MARSHALL STEAM STATION DUKE ENERGY CAROLINAS, LLC, TERRELL, NC Initial Purpose Well ID Proposed Screen Interval' (ft bgs) Comments 2 Industrial Landfill ILF-1S 30-40 Estimated depths based on AB-17D boring log ILF-1D 80-90 ILF-16R 120-130 No. 1 ILF-2S 30-40 ILF-2D 70-80 PV Structural Fill PVSF-1S 15-25 Estimated depths based on A13-6 cluster boring logs PVSF-1D 40-50 PVSF-1BR 90-100 PVSF-2S 20-30 Estimated depths based on AB-15 cluster boring logs PVSF-2D 55-65 PVSF-2BR 90-100 PVSF-3S 10-20 Estimated depths based on GWA-3 cluster boring logs PVSF-3D 35-45 PVSF-3BR 60-70 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. The actual number of wells to be installed at each location are subject to change based on field observations P:\Duke Energy Carolinas\18. MARSHALL\06.EHS CAMA Compliance Support\06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\ Table 1 Proposed Data Gap Evaluation Locations 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/kgmg/kg 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. Ash samples to be analyzed for Total Inorganics using USEPA Methods 6010/6020 and pH using USEPA Method 9045; select ash samples will also be analyzed for leaching potential using SPLP Extraction Method 1312 in conjunction with USEPA Methods 6010/6020. 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. MARSHALL\06.EHS CAMA Compliance Support\06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\ 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 oC Field Water Quality Meter Dissolved Oxygen NA m L Field Water Quality Meter Oxidation Reduction Potential NA mV Field Water Quality Meter Turbidity NA NTU ality Meter Ferrous Iron NA m L Field Test Kit INORGANICS Aluminum 0.005 m L EPA 200.7 or 6010D Antimony 0.001 m L EPA 200.8 or 6020E 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 EPA 200.8 or 6020A Zinc 0.005 m L EPA 200.7 or 6010C RADIONUCLIDES Radium 226 1 1 PQ/L 1EPA 903.1 Modified Radium 228 1 1 PQ/L I EPA 904.0/SW846 9320 Modified Uranium 233 234 236 238 Varies by isotope I µg/mL ISW846 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 m 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 ism 5310C EPA9060A Total Suspended Solids 1 2.5 1 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 pS/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\06.EHS CAMA Compliance Support\06N. Data Gap Evaluation Work Plan\Data Gap Work Plan\Table 3 - GW Analytical Methods Page 1 of 1