Loading...
HomeMy WebLinkAboutNC0005088_Add Assessment Revised Work Plan_20170512DUKE ENERGY. May 12, 2017 Mr. S. Jay Zimmerman, Director Division of Water Ruaworc -s North Caroli, a Depart, r rent of Envirunr trental Quality 15 i r Mail Service Center Rialu;gh, North Varuli, in 27699-1611 Environmental, ReallM & Surety 526 South Churcn Street: Ma!l CoU. ECi3K Ch.riah., Nartfi Carolina 28202 Subject: Additional Site Assessment Revised Work Plan James E. Rogers Energy Complex (furrnerly Cliffside Steam Station) Muuri:-;aburu, Ratherfurd and Cleveland Counties_ North Carolina NPDE< S Permit NCOU05055 Dear Mr. Zimmerman: In a letter dated April 19.2011. Dake Energy (Duke) communicated to the North Carolina Department of Environmental u.ality DivEaiun of Water Re5uarce5 (DWR) that a revised wurk plan for additional a53u5 munt activities at the James E. Rogers Energy Complex (Rogers) would be sabmMed no later tnan May 12, 2017. Duke hereby aabrnita thu ruviaed ..ork plan ft,r Rogers that incurpurtes an extended ash area bensaih the Unit 5 Switchyard. If you have questions concerning thin aite, you may contaLt Ryan Cz-vp at 980-373-2779. Sincerely, D. Ed..in M. Sullivan Director, Waste & Groundwater Programs environmental, Health, & 5ufuty cc NCDEQ (electronic): Ted Camplsell - MCDEu Asheville Regional Office Landun Da„idaun - NCDEu Ashevilla Regional Office Steve Lanter - NCDEQ Raleigh Eric Smith - NCDLw Raleigh cc Doke (electronic) Ryan Ccop FN Proposed Groundwater Assessment Revision Additional Assessment of Coal Ash Disposal Area This document has been reviewed for accuracy and quality commensurate with the intended application. Mark P. Filardi, P.G. Senior Geologist Duke Energy Carolinas, LLC I Cliffside Steam Station FN Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Contents Section1 — Introduction............................................................................................................. 1 Section 2 — Proposed Groundwater Assessment Plan............................................................... 5 2.2 Monitoring Well Installation.......................................................................................... 5 2.1.1 Well Installation Methods and Construction Requirements .................................... 6 2.1.1.1 Monitoring Well Construction............................................................................. 7 2.1.1.2 Monitoring Well Surface Completion................................................................. 7 2.1.2 Well Development................................................................................................. 7 2.1.3 Well Survey.......................................................................................................... 8 2.1.4 Investigative Derived Waste.................................................................................. 8 2.1.5 Documentation......................................................................................................8 2.2 Sample Collection and Analysis................................................................................... 9 2.2.1 Soil and Ash Sampling.......................................................................................... 9 2.2.1.1 Sampling Procedures........................................................................................ 9 2.2.1.2 Constituent Analyses........................................................................................10 2.2.2 Groundwater Sampling........................................................................................11 2.2.2.1 Groundwater Level Measurements...................................................................11 2.2.2.2 Groundwater Purging and Sampling Procedures..............................................12 2.2.2.3 Constituent Analyses........................................................................................12 2.2.3 Surface Water Sampling......................................................................................14 2.2.4 Area of Wetness Identification and Sampling.......................................................14 Section 3 — Proposed Quality Assurance Plan..........................................................................15 3.1 Field Documentation...................................................................................................15 3.1.1 Field Logbooks....................................................................................................15 3.1.2 Field Data Records..............................................................................................15 3.2 Laboratory Documentation..........................................................................................16 3.3 Quality Control............................................................................................................17 3.3.1 Field Duplicates...................................................................................................17 3.3.2 Field Blanks.........................................................................................................17 3.3.3 Data Validation....................................................................................................17 Section4 — Reporting................................................................................................................18 Section 5 — Proposed Schedule for Assessment.......................................................................19 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan: Additional Assessment of Coal Ash Disposal Area Across the Broad River FIGURES Figure 1. Site Location Map Figure 2. Proposed Monitoring Well, Surface Water Sample, and Soil Boring Location Map Figure 3. Shallow Monitoring Well Construction Details TABLES Table 1. Proposed Monitoring Well Installation Plan Table 2. Soil and Ash Parameters and Constituent Analytical Methods Table 3. Groundwater Parameters and Constituent Analytical Methods Table 4. Proposed Schedule for Additional Assessment of Coal Ash Disposal Area across the Broad River APPENDICES Appendix A — "Additional Site Assessment Required" letter, July 8, 2016. "Conditional Additional Site Assessment Approvals" letter, November 23, 2016. "Correction to the Conditional Additional Site Assessment Approvals", dated December 2, 2016. "Extension Request — Additional Areas Assessment", dated February 27, 2017. "Additional Site Assessment", dated April 19, 2017. Appendix B — Low Flow Sampling Plan, Duke Energy Facilities, Ash Basin Groundwater Assessment Program, North Carolina, June 10, 2015. Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Section 1 — Introduction Duke Energy Carolinas, LLC (Duke Energy) owns and operates the Cliffside Steam Station (CSS) located in Mooresboro in Rutherford and Cleveland Counties, North Carolina (Figure 1). CSS began operations in 1940 with Units 1 through 4. Unit 5 began operations in 1972 followed by Unit 6 in 2012. Units 1 through 4 were retired from service in 2011 as part of Duke Energy's decommissioning and demolition program and were imploded in October 2015. Currently, only Units 5 and 6 are in operation. Coal ash residue and other liquid discharges from CSS's coal combustion process have been disposed in the station's ash basin system since its construction. The ash basin system consists of the active ash basin, Units 1 through 4 inactive ash basin, and Unit 5 inactive ash basin. Discharge from the active ash basin is permitted by the North Carolina Department of Environmental Quality (NCDEQ)' Division of Water Resources (DWR) under the National Pollutant Discharge Elimination System (NPDES) Permit NC0005088. On November 16, 2015, while conducting a field reconnaissance in preparation of a U.S. Army Corps of Engineers site wetlands jurisdictional determination, Duke Energy personnel noticed some raised areas on undeveloped land northwest of the Unit 5 Switchyard. This area is located on the north side of the Broad River. Upon further investigation, Duke Energy personnel determined that the raised areas exhibited visual characteristics of ash and reported the identification of the historic ash disposal areas to NCDEQ on the same day. Subsequent to reporting its presence, Duke Energy collected four solid -matrix samples from the areas and confirmed that the sampled material was ash. Additional hand auger borings were advanced to delineate the extent of ash. The results of this investigation indicated that three ash areas were present northwest and west of the Unit 5 Switchyard with estimated areas of 19,000 square feet (sq ft), 35,000 sq ft, and 6,500 sq ft, or a total of 1.38 acres. Ash thickness ranged from 3 feet to 8 feet within the three areas. Duke Energy estimates the volume of ash placed in these areas to total approximately 11,000 cubic yards. The NCDEQ issued a letter to Mr. Harry Sideris of Duke Energy, dated July 8, 2016, requiring that additional assessment of this area be conducted in accordance with the North Carolina Department of Environment and Natural Resources Notice of Regulatory Requirements letter dated August 13, 2014, and Coal Ash Management Act of 2014 (CAMA) and that site activities shall follow the requirements under 15A NCAC 02L .0106(g). A copy of the NCDEQ letter is included in Appendix A. A Proposed Groundwater Assessment Plan (GAP) was developed to provide an assessment program for characterizing coal combustion residuals (CCR) in the historical coal ash disposal areas. The GAP was submitted to NCDEQ on August 19, 2016, and conditionally approved by NCDEQ in a letter to Mr. Harry Sideris of Duke Energy dated November 23, 2016, which was revised in a letter dated December 2, 2016. A copy of the NCDEQ conditional approval and ' Prior to September 18, 2015, the NCDEQ was referred to as the North Carolina Department of Environment and Natural Resources (NCDENR). Both naming conventions are used in this document, as appropriate. Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River revised approval letters are included in Appendix A. The letters provided NCDEQ's approval of the GAP contingent upon the following site-specific conditions: • Include the AMEC Foster Wheeler ash sampling results (map and tabular data) in the groundwater assessment report that will be provided following the site investigation. • If monitoring well data indicate exceedances of the 2L Standards, notify the NCDEQ Asheville Regional Office (ARO) immediately so that deeper wells may be located and installed expeditiously. • NCDEQ concurred with the proposed boring/well locations and the sample depth intervals for purposes of Unified Soil Classification System descriptions. • Revisions to the soil/ash sampling requirements. For each of the six ash -related boring locations, a lab analysis (constituents are listed in GAP Table 2) should be conducted for all sampled depth intervals that contain visual evidence of ash. If four or more intervals contain ash, conduct a lab analysis only on the shallowest ash interval, the deepest ash interval, and a composite of the remaining ash intervals, for a total of three ash lab analyses. NCDEQ concurs with the 5 -foot thickness, as a minimum, criterion to determine when to analyze for variations in ash type (fly or bottom). • For soil sampling and lab analysis at the six ash -related boring locations, NCDEQ concurs with the two proposed sample intervals: 2 feet below the ash/soil interface and 8 feet to 10 feet below the ash/soil interface. • For the Synthetic Precipitation Leaching Procedure (SPLP) analysis at each of the six ash -related boring locations, please conduct analysis on: o The sampled ash interval with the highest concentration of arsenic, selenium, and strontium among all sampled ash intervals at that location, and o A sample composited from the two sampled soil intervals at that location. • For soil sampling and analysis at the background boring location, please collect: o One shallow soil sample at a depth that approximates the general depth of most of the shallow soil samples from the other six borings, o One deeper soil sample at a depth that approximates the general depth of most of the deeper soil samples from the other six borings, and o One SPLP sample that is a composite of the shallow and deeper intervals in the first two bullets above. • Revise Section 2.2.3 to read that if inaccessible from the bank, a boat should be used to collect three surface water samples upstream, adjacent to, and downstream of the Areas of Interest (AOIs). These samples should be collected immediately adjacent to the bank during conditions that approximate low or baseflow to the maximum extent possible and at least 5 days after a previous rain event of any magnitude. Contact NCDEQ's ARO if this request becomes difficult to meet based on weather conditions. Antecedent rainfall (prior 5 days and prior 48 hours) should be provided, along with its measurement location, as a footnote in the surface water results table. • Submit the findings of the site assessment as a groundwater site assessment report. The site assessment report shall include figures, tables, cross-sections, and maps in a Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River manner that provides an interpretation of site conditions. Include a map that shows all private supply wells, monitoring well locations, any areas of wetness (AOWs) and surface water features within one-half- mile radius of a previously established compliance boundary around the study area. Reports submitted in a data summary format will not be approved as an acceptable documentation of findings. Submit the site assessment report by March 31, 2017. The NCDEQ conditional approval conditions of the GAP have been incorporated into this GAP Revision 1. In a January 27, 2017, letter to NCDEQ, Duke Energy requested an extension for the additional area site assessment at CSS until all the ash was removed from the area across the Broad River west of the Unit 5 Switchyard. On February 27, 2017, Duke Energy received an extension from NCDEQ DWR for additional assessment activities until all the ash was removed from the area across the Broad River near the Unit 5 Switchyard. A copy of the NCDEQ letter is included in Appendix A. The letter stipulated that the extension approval is contingent on updated status reports provided to the NCDEQ ARO at the first of each month consisting of documentation of permit issues, schedules for sample collection and analysis, and time estimates for reporting. On March 9, 2017, Duke Energy personnel at CSS identified potential ash at the Unit 5 Switchyard while installing inlet protection for stormwater runoff. On March 13, 2017, four locations at the switchyard were sampled at an average depth of 11 inches below ground surface (bgs). The testing of the soil samples for the presence of coal ash particles was performed using visual estimation via Polarized Light Microscopy (PLM) and confirmed the presence of ash. The NCDEQ DWR ARO was verbally notified via telephone on March 27, 2017 and via electronic mail on March 29, 2017. The email explained that ash was discovered beneath the Unit 5 Switchyard at CSS. A preliminary estimate of the total switchyard footprint area using Google Earth is approximately 356,212 sq ft. The previously discovered ash areas west of the switchyard were calculated to be 59,751 sq ft. The switchyard was reportedly constructed in the early 1970s prior to Unit 5 beginning operation in 1972, but Duke Energy is not certain of the date. The NCDEQ Solid Waste Section ARO was also verbally notified of the ash discovery at the Unit 5 Switchyard and copied in the March 29, 2017, email transmission. Duke Energy communicated its intent to incorporate the Unit 5 Switchyard into the additional assessment investigation across the Broad River. Duke Energy also communicated this intent in a letter to Jay Zimmerman, Director, NCDEQ DWR on April 19, 2017. The letter states that Duke Energy will proceed with the assessment of the area prior to making a decision regarding ash removal and that ash was discovered beneath the Unit 5 Switchyard and will be incorporated into a revised GAP submitted to NCDEQ DWR no later than May 12, 2017. A copy of the April 19, 2017, letter is included in Appendix A. Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Proposed monitoring well locations were sent to NCDEQ DWR on April 19, 2017, and discussed in person on April 24, 2017, in a meeting at the NCDEQ ARO. Revisions to the quantity and locations of the proposed monitoring well locations resulting from the April 24, 2017, meeting have been incorporated into this GAP Revision 1. The locations of the monitoring well and soil boring locations may change due to pending permitting issues and proximity to overhead high voltage power lines. The ash locations described in the July 8, 2016, letter from NCDEQ and the area beneath the Unit 5 Switchyard are herein referred to as the AOIs for this groundwater assessment. Duke Energy Carolinas, LLC I Cliffside Steam Station Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Section 2 — Proposed Groundwater Assessment Plan Duke Energy proposes to perform an additional groundwater assessment within and adjacent to the AOls located north of the Broad River. The purpose of the additional assessment is to characterize the CCR found within the AOIs and to determine the extent of potential groundwater and soil contamination associated with the CCR in AOIs. In addition, surface water quality and AOW, if present, will be assessed pursuant to CAMA §130A-309.212. Duke Energy proposes to conduct field sampling and laboratory analyses as described in the following sections. After review of the results from these activities, Duke Energy will evaluate the need for additional investigation, sampling, and analyses. This approach is further discussed in Section 5. 2.1 Monitoring Well Installation Duke Energy proposes to install a total of 13 shallow monitoring wells to evaluate groundwater flow direction and quality beneath and downgradient of the AOIs, as shown on Figure 2. Samples of ash and soil will be collected for laboratory analyses during installation of select monitoring wells. Seven shallow wells are proposed within and downgradient of AOIs 1, 2, and 3; five wells are proposed downgradient of the Unit 5 Switchyard; and one shallow well in a location upgradient of the Unit 5 Switchyard to provide background groundwater quality data for comparison. Total well depths are estimated at 60 feet bgs. Well screens will be installed to bracket the water table at the time of installation. Approximate well locations are provided in the table below. Note that steep slopes north of AOI 1 prohibit access for well installation. Duke Energy Carolinas, LLC I Cliffside Steam Station Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Table 1. Proposed Monitoring Well Installation Plan AD1-1 South of Area 1 AD2-1 Southeast of Area 2 AD2-2 South of Area 2 AD2-3 South of Area 2 AD2-4 Central portion of Area AD3-1 Southeast of Area 3 AD3-2 South of Area 3 SY-1 South of Unit 5 Switchyard SY-2 South of Unit 5 Switchyard SY-3 South of Unit 5 Switchyard SY-4 South of Unit 5 Switchyard SY-5 East of Unit 5 Switchyard Groundwater flow and quality downgradient of Area 1 Groundwater flow and quality downgradient of Area 2 Groundwater flow and quality downgradient of Area 2 Groundwater flow and quality downgradient of Area 2 Groundwater flow and quality beneath Area 2; collect ash and soil samples Groundwater flow and quality downgradient of Area 3 Groundwater flow and quality downgradient of Area 3 Groundwater flow and quality downgradient of Unit 5 Switchyard Groundwater flow and quality downgradient of Unit 5 Switchyard Groundwater flow and quality downgradient of Unit 5 Switchyard Groundwater flow and quality downgradient of Unit 5 Switchyard Groundwater flow and quality downgradient of Unit 5 Switchyard SY-BG-1 Background north of Unit 5 Groundwater flow and background Switchyard groundwater quality; collect soil samples 2.1.1 Well Installation Methods and Construction Requirements Monitoring wells will be installed using drilling equipment appropriate for the terrain at each drill site. The drilling equipment will be clean and free from dirt, debris, and contaminants. Drilling will be conducted in accordance with appropriate standard -of -care for the specified drilling technology. Drill crews will be trained and experienced using the specific drilling techniques and equipment. Monitoring wells will be constructed by a North Carolina -licensed driller in accordance with the NCDEQ Division of Water Quality standards, as specified in T1 5A NCAC 02C and under the direction of a North Carolina -licensed geologist. Bentonite -based or synthetic -based drilling fluids are not anticipated for use during installation of the monitoring wells. Only water from the actual boring or an approved source will be used for drilling. All storage containers used for transportation or storage of the water will be new or properly decontaminated prior to use at the site. Decontamination of downhole drilling equipment (such as augers, drill rods, cutting heads, etc.) will be completed between well locations. After completion of a well, a water pressure cleaner will be used to decontaminate downhole tooling prior to reuse. If needed, brushes and water from an approved source will be used to remove excess soil, mud, or other material from drilling equipment. The decontamination water will be place directly to the ground surface away from the drilling location. 6 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River 2.1.1.1 MONITORING WELL CONSTRUCTION Shallow (single -cased) monitoring wells (S wells) will be installed to bracket the water table encountered in unconsolidated material (i.e., regolith or overburden) at the time of drilling and a 10 -foot to 15 -foot screen will be installed. A single -cased well will be constructed with a 2 -inch - inner diameter (ID), Schedule 40 flush -joint -threaded PVC pipe fitted with a 20/40 (sand) pre - packed PVC 0.010 -slot screen and a 2 -inch ID Schedule 40 PVC casing to the ground surface. An additional filter pack (#2 sand) will be placed to at least 1 foot above the screen with a minimum of a 1 -foot to 2 -foot bentonite seal placed above the filter pack. The remaining annular space will be grouted with a Portland cement -bentonite slurry to the ground surface using positive displacement (i.e., tremie grout method). The monitoring well will be fitted with a lockable well cap. For shallow monitoring well construction details see Figure 3. 2.1.1.2 MONITORING WELL SURFACE COMPLETION Each well will be finished at the ground surface with a 2 -foot by 2 -foot concrete well pad and a 4 -inch or 8 -inch steel or aluminum above -grade lockable protective cover. All wells will be locked with a keyed padlock. Bollards will be installed as needed to protect monitoring wells from potential damage from vehicles and/or heavy equipment. 2.1.2 Well Development Each monitoring well will be developed prior to commencing groundwater sampling activities. Monitoring well development will be performed in general accordance with the following procedures. Deviations from these procedures will be verified by the Project Manager prior to implementation. 1. Monitoring well development will not be performed until 24 hours have passed after well completion to allow for grout/cement curing. 2. The duration of development, initial water level, well depth, development method (i.e., bailing, surging, pumping), and field parameter measurements (listed in item #4 below) will be documented on a Well Development Record. 3. Monitoring wells will be developed using pumping and surging techniques. The wells will be pumped using a centrifuge or submersible pump (Wahl, Monsoon, or equivalent) to remove suspended particles and induce flow into the well to prevent clogging of the filter pack. For wells that cannot be developed utilizing a pump due to insufficient volume, a bailer may be used to evacuate the well. If it is determined by the developers that there is a significant sediment slug at the bottom of the well, it can be removed using a foot valve pump or bailer in lieu of the centrifugal or submersible pump. Once removed, well development will continue with the centrifugal or submersible pump. 4. Field parameter measurements of dissolved oxygen (DO), oxidation reduction potential (ORP), pH, temperature, specific conductivity, and turbidity will be recorded for every 5 gallons of discharge. A 5 -gallon bucket can be used for purge water volume measurements. For wells with slow recovery, field parameters will be checked every 2 gallons of discharge. Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River 5. Pumping should begin at the top of the well screen with low pumping rates and incrementally work down the screen. The well will be surged periodically by raising and lowering the pump within the water column three to five times in succession, being careful not to touch the bottom of the well with the pump. If turbidity values remain over 10 Nephelometric Turbidity Units (NTU), the well will be allowed to equilibrate (90 percent or greater of the original static water level) and the process repeated. 6. Development will continue for a minimum of 1 hour or three well volumes (whichever duration is longer) until turbidity is less than 10 NTUs and until monitoring parameters of pH, temperature, conductivity, and turbidity are generally stabilized. 7. If development has continued past 3 hours and turbidity values remain in excess of 10 NTUs, the well should be allowed to equilibrate for 24 hours or 90 percent of the original static water level, and the development process will be repeated until turbidity is less than 10 NTUs. If turbidity does not reduce after multiple developments, the development team will notify the Project Manager as soon as possible to discuss other options to resolve current conditions, including reinstallation. 8. Following development, sounding the bottom of the well with a water level meter should indicate a "hard" (sediment -free) bottom. 2.1.3 Well Survey Newly installed monitoring wells will be surveyed for horizontal and vertical locations by a North Carolina -licensed surveyor. The measuring points will include: 1) the top of the 2 -inch PVC well casing elevation, and 2) ground surface at each monitoring well in the groundwater monitoring network. The location and position accuracy will be approximately 1.0 foot for horizontal control, 0.1 foot for ground surface elevation, and 0.01 foot for well top -of -casing elevation. 2.1.4 Investigative Derived Waste IDW such as nitrile gloves, paper towels, and other miscellaneous waste generated during well installation will be bagged, placed in a commercial dumpster, and managed as municipal solid waste. Soil cuttings generated during drilling will be spread near monitoring well locations so that it is not a safety concern and seed/straw will be applied to aid in restoration, or disposed of at the onsite CCP Landfill. Water generated during decontamination of equipment, monitoring well development, and sampling will be discharged to the ground surface in the vicinity of the decontamination pad or monitoring well location. 2.1.5 Documentation Documentation of field activities will be completed using a combination of log books and field forms. Log books are completed to provide a general record of activities and events that occur during daily tasks (e.g., detailed descriptions of subsurface media encountered and observations made during boring installation). During well installation and development of the monitoring wells, the following field forms will be used for documentation: Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River • Boring logs will be utilized to document lithology and details of boring advancement. • Monitoring well construction logs will be utilized to detail final well construction details. • Monitoring well development record forms will be utilized to document details of well development for each newly installed monitoring well (see Section 2.1.2). Duke Energy will submit a well construction record to NCDEQ (NCDEQ Form GW -1) for newly installed groundwater monitoring wells. 2.2 Sample Collection and Analysis For this GAP Revision 1, sampling will consist of collection and analysis of soil, ash, groundwater, surface water, and AOW (if present) samples. 2.2.1 Soil and Ash Sampling Soil and ash samples will be collected from monitoring well locations AD2-4 and SY-BG-1 and from soil boring locations AD1-SB-1, AD2-SB-1, and AD3-SB-1 (Figure 2). 2.2.1.1 SAMPLING PROCEDURES Split -spoon (SPT) and disturbed sampling is proposed during installation of wells and soil borings using a split -spoon sampler driven 18 inches into the ground with an automatic 140 - pound hammer. SPT will be conducted on 5 -foot centers (3 feet between samples) for ash fill materials and the underlying in-situ soils (e.g., 4 feet to 6 feet, 9 feet to 11 feet, 14 feet to 16 feet, 19 feet to 21 feet). After collection, the sampler will be opened and recovered material will be described in the field in accordance with the Unified Soil Classification System (USCS). For each of the identified soil and ash sampling locations, a sample will be collected for analysis for the constituents on Table 2 for all sample depth intervals that contain visual evidence of ash. For borings where the ash thickness is greater than 5 feet, shallow and deep ash samples will be collected to evaluate variations in type (e.g., fly ash or bottom ash) and chemical profile of the ash. Shallow ash samples will be collected from the 1 -foot to 2 -foot intervals and deeper ash samples will be collected from the 1 -foot to 2 -foot intervals overlying the ash/soil interface. The depth of deep ash samples is expected to vary based on ash thickness at each specific well location. If four or more sample intervals contain ash, lab analysis will only be conducted on (1) the shallowest ash interval, (2) the deepest ash interval, and (3) the remaining ash intervals will be composited and samples of each of these will be submitted for analysis, for a total of three ash samples for analyses. Soil samples will be collected below the ash/soil interface, but prior to auger refusal, to characterize soil quality beneath the AOIs. Soil samples will be collected approximately 2 feet below the ash/soil interface and approximately 8 feet to 10 feet below the ash/soil interface. If groundwater is encountered prior to 8 feet to 10 feet below the ash/soil interface, this deeper soil sample will be collected from approximately 2 feet above the water table. For soil sampling and analysis at background location (SY-BG-1), the following soil and ash samples will be collected: Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River • One shallow soil sample at a depth that approximates the general depth of most of the shallow soil samples from the other soil/ash borings, • One deeper soil sample at a depth that approximates the general depth of most of the deeper soil samples from the other soil/ash borings, and • One SPLP sample that is a composite of the shallow and deeper intervals in the first two bullets above. 2.2.1.2 CONSTITUENT ANALYSES Duke Energy proposes to analyze soil and ash samples for parameters and constituents consistent with those analyzed during the Comprehensive Site Assessment (CSA) at CSS in 2015. The laboratory analytical methods employed will be consistent with the methods used during the CSA. The soil analytical results will be compared to the North Carolina Preliminary Soil Remediation Goals (PSRGs) for Industrial Health and Protection of Groundwater Standards. In addition, at each soil and ash sampling location, the ash sample with the highest concentrations of arsenic, selenium, and strontium reported among all sampled ash intervals at that location and a sample composited from the two sampled soil intervals at that location will be analyzed for leaching potential using SPLP. Results of the SPLP analyses will be compared to the North Carolina Groundwater Quality Standards as specified in T15A NCAC 2L.0202 (21- Standards) 2LStandards) or Interim Maximum Allowable Concentration (IMAC) established by NCDEQ pursuant to T1 5A NCAC 2L.0202(c), or North Carolina Department of Health and Human Services (NCDHHS) Health Screening Level (HSL) (hexavalent chromium only), although these samples do not represent groundwater samples. A list of proposed parameters and constituents as well as proposed analytical methods is presented in the table below. 10 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Table 2. Soil and Ash Parameters and Constituent Analytical Methods INORGANIC COMPOUNDS• Aluminum Antimony mg/kg mg/kg . EPA 6010 EPA 6020 Arsenic mg/kg EPA 6020 Barium mg/kg EPA 6010 Beryllium mg/kg EPA 6010 Boron mg/kg EPA 6010 Cadmium mg/kg EPA 6020 Chloride mg/kg EPA 9056 Chromium (Total) mg/kg EPA 6010 Hexavalent Chromium (CrVI) (low level) mg/kg EPA 3060 Cobalt Copper mg/kg mg/kg EPA 6020 EPA 6010 Iron mg/kg EPA 6010 Lead mg/kg EPA 6020 Manganese mg/kg EPA 6010 Mercury mg/kg EPA 7471 Molybdenum mg/kg EPA 6020 Nickel mg/kg EPA 6010 pH SU EPA 9045 Selenium mg/kg EPA 6020 Strontium mg/kg EPA 6020 Thallium (low level) Vanadium Zinc mg/kg mg/kg mg/kg EPA 6020 EPA 6020 EPA 6010 Calcium mg/kg EPA 6010 Magnesium mg/kg EPA 6010 Nitrate mg/kg EPA 9056 Nitrogen mg/kg EPA 353.2 Potassium mg/kg EPA 6010 Sodium mg/kg EPA 6020 Sulfate mg/kg EPA 9056 Total Organic Carbon mg/kg EPA 9060 Modified Notes: 1. mg/kg — milligrams per kilogram 2. SU — standard units 3. Soil samples to be analyzed for Total Inorganics using the methods noted above. 4. Ash samples to be analyzed for Total Inorganics using the methods noted above; select ash samples will also be analyzed for leaching potential using SPLP Extraction Method 1312 in conjunction with USEPA Methods 6010/6020. SPLP results to be reported in units of pg/L for comparison to 2L Standards, IMACs, or DHHS HSL, as applicable. 2.2.2 Groundwater Sampling 2.2.2.1 GROUNDWATER LEVEL MEASUREMENTS Prior to groundwater purging and sampling activities, a depth -to -water (DTW) measurement will be measured in each well during a 24-hour to 48-hour period. Groundwater levels will be measured using an electronic water level indicator that will be decontaminated between each well prior to measurement activities. The DTW measurements will be referenced to the well top - 11 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River of -casing mark established by a site survey and will provide data to generate a potentiometric surface for the area. 2.2.2.2 GROUNDWATER PURGING AND SAMPLING PROCEDURES Subsequent to well installation and development, groundwater samples will be collected from each monitoring well using low flow sampling techniques as outlined in the Low Flow Sampling Plan, Duke Energy Facilities, Ash Basin Groundwater Assessment Program, North Carolina, June 10, 2015 (Low Flow Sampling Plan) (Appendix B) to minimize sampling error and prevent cross contamination of samples. Groundwater purging and sampling will be conducted using new or dedicated tubing for each well. Bladder, peristaltic, and/or submersible pumps will be utilized to achieve minimum drawdown. Purge water will be pumped from the monitoring well into a flow-through cell, which will allow for monitoring of field parameters using an YSI Professional Plus multi -parameter water quality meter or similar instrument. Turbidity will be measured using a separate turbidity meter. Field parameters to be measured during purging and sampling will include pH, temperature, specific conductivity, DO, ORP, and turbidity, and are listed below in Table 3. 2.2.2.3 CONSTITUENT ANALYSES Pace Analytical Services, Inc. (Pace) or another laboratory certified in North Carolina will analyze groundwater samples for the constituents and analytical methods listed in Table 3. The record of groundwater analyses will include the methods used (by number), the extraction date (if applicable), and the date of analysis. Data obtained from samples that are not analyzed within the recommended holding times will be considered suspect and flagged accordingly. Any deviation from approved methods will be adequately tested to ensure that the quality of the results meets the performance specifications (e.g., detection limit, sensitivity, precision, accuracy) of the reference method. 12 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Table 3. Groundwater Parameters and Constituent Analytical Methods FIELD PARAMETERS H AM.. NA SU Field Water Quality Meter Specific Conductance NALIS/cm Field Water Quality Meter Temperature NA °C 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 Field Water Quality Meter Ferrous Iron NA mg/L Field Test Kit INORGANICS Aluminum 5 /L EPA 200.7 or 200.8 Antimony 1 /L EPA 200.7 or 200.8 Arsenic 1 pg/L EPA 200.7 or 200.8 Barium 5 /L EPA 200.7 or 200.8 Beryllium 1 pg/L EPA 200.7 or 200.8 Boron 50 /L EPA 200.7 or 200.8 Cadmium 1 u /L EPA 200.7 or 200.8 Chromium 1 g/L EPA 200.7 or 200.8 Hexavalent Chromium 0.07 /L EPA 200.7 or 200.8 Cobalt 1 g/L EPA 200.7 or 200.8 Copper 0.005 mg/L EPA 200.7 or 200.8 Iron 10 /L EPA 200.7 or 200.8 Lead 1 /L EPA 200.7 or 200.8 Manganese 5 pg/L EPA 200.7 or 200.8 Mercury 0.2 uq/L EPA 245.1 Molybdenum 0.5 /L EPA 200.7 or 200.8 Nickel 1 /L EPA 200.7 or 200.8 Selenium 1 /L EPA 200.7 or 200.8 Strontium 5 pg/L EPA 200.7 or 200.8 Thallium (low level) 0.2 /L EPA 200.7 or 200.8 Vanadium (low level) 0.3 pg/L EPA 200.7 or 200.8 Zinc 5 /L EPA 200.7 or 200.8 ANIONS/CATIONS Alkalinity (as CaCO3) 20 m /L SM 2320B Bicarbonate 20 m /L SM 2320B Calcium 0.01 mg/L EPA 200.7 or 200.8 Carbonate 20 mg/L SM 2320B Chloride 0.1 m /L EPA 300.0 Magnesium 0.001 m /L EPA 200.7 or 200.8 Methane 0.1 m /L RSK 175 Nitrate as Nitrogen 0.02 mg-N/L EPA 353.2 Potassium 0.1 m /L EPA 200.7 or 200.8 Sodium 0.05 m /L EPA 200.7 or 200.8 Sulfate 0.1 m /L EPA 300.0 Sulfide (as 1-12S) 0.05 mg/L SM4500S2-D Total Dissolved Solids 25 m /L SM 2540C Total Organic Carbon Total Suspended Solids 0.1 2 m /L mg/L SM 53108 SM 2540D f Notes: 1. Units: SU - standard units; µS/cm - microsiemens per centimeter; °C - degrees Celsius; mg/L - milligrams per liter; mV - millivolts; NTU - Nephelometric Turbidity Unit; pg/L - microgram per liter; mg-N/L - milligrams nitrogen per liter. 2. RL is the laboratory analytical method reporting limit. 3. NA indicates not applicable. 4. Sulfide (as 1-12S) will be analyzed for groundwater samples only. 5. All EPA methods and RLs are at or below the respective 2L Standard for constituents with standards. 13 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Sample preservation and handling will be conducted in accordance with the procedures specified in 3.5.1 and 3.5.2 of the Low Flow Sampling Plan (Appendix B). Decontamination will be conducted in accordance with the procedures specified in Appendix A (Decontamination of Equipment Standard Operating Procedure) of the Low Flow Sampling Plan (Appendix B). If groundwater monitoring well data indicate exceedances of the 2L Standards, the NCDEQ ARO will be identified so that deeper wells may be located and installed expeditiously to determine the vertical extent of groundwater contamination if determined to be necessary. 2.2.3 Surface Water Sampling If accessible from the bank of the Broad River, Duke Energy will collect three surface water samples upstream, adjacent to, and downstream of the AOIs from the approximate locations identified on Figure 3. Samples will be obtained using a telescoping cup sampler and will be analyzed for the same list of parameters and constituents, using the same laboratory analytical methods as the groundwater samples (listed in Table 3). If inaccessible from the bank, a boat will be used to collect the three surface water samples upstream, adjacent to, and downstream of the AOIs. These samples will be collected immediately adjacent to the bank during conditions that approximate low or baseflow to the maximum extent possible and at least 5 days after a previous rain event of any magnitude. NCDEQ's ARO will be contacted if this request becomes difficult to meet based on weather conditions. Antecedent rainfall (prior 5 days and prior 48 hours) should be provided, along with its measurement location, as a footnote in the surface water results table included in the groundwater site assessment report (see Section 4). 2.2.4 Area of Wetness Identification and Sampling Duke Energy will conduct a field reconnaissance of the riverbank downgradient of the AOIs to identify AOWs. If identified and if flow is present, AOWs will be sampled and analyzed for the same list of parameters, constituents, and laboratory methods as the groundwater samples (listed in Table 3). 14 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Section 3 — Proposed Quality Assurance Plan The Quality Assurance Plan (QAP) has been prepared to specify quality assurance/quality control (QA/QC) procedures for collection, analysis, and evaluation of data that will be legally and scientifically defensible. The QAP provides general information and references standard operating procedures applicable to the analytical sampling program. This information includes definitions and generic goals for data quality and required types and quantities of QA/QC samples. The procedures address field documentation; sample handling, custody, and shipping; instrument calibration and maintenance; auditing; data reduction, validation, and reporting; corrective action requirements; and QC reporting specific to the analysis performed by the NCDEQ-approved laboratory. 3.1 Field Documentation Documentation of field activities will be completed using a combination of field log books, field data records (FDRs), sample tracking systems, and sample custody records. The log books and field data sheets will be completed to provide a general record of activities and events that occur during each field task. Field data sheets and/or sample custody records are used to provide a complete record of data collected during sampling. 3.1.1 Field Logbooks Field logbooks will provide a daily hand-written account of field activities. The logbooks will be hardcover books that are permanently bound. All entries will be made in indelible ink and corrections will be made with a single line with the author initials and date. Each page of the logbook will include the job number, date, and initials of the person completing the log. Partially completed pages will have a line drawn through the unused portion at the end of each day with the author's initials. The following general information will be entered into the field logbooks: • The date and time of each entry. The daily log will begin with a safety brief. • A summary of important tasks or subtasks completed during the day. • A description of field test completed in association with the daily task. • A description of samples collected including documentation of any quality control samples that were prepared (i.e., rinse blanks, duplicates, matrix spike, split samples, etc.). • Documentation of equipment maintenance and calibration activities. • Documentation of equipment decontamination activities. • Descriptions of deviations from the work plan. 3.1.2 Field Data Records FDRs will contain sample collection and/or exploration details. A FDR will be completed each time a field sample is collected. The goal of the FDR is to document exploration and sample collection methods, materials, dates and times, and sample locations and identifiers. Field measurements and observations associated with a given exploration or sample collection task will be recorded on the FDRs. FDRs will be maintained throughout the field program in files that become a permanent record of field program activities. A listing of FDRs is presented below. 15 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan: Additional Assessment of Coal Ash Disposal Area Across the Broad River Each FDR listed will not be required for each step -specific activity that may or may not be required over the entire project. Examples of FDRs include: • Groundwater Potentiometric Level Measurement Log • Well Sampling/Low Flow Sampling Log • Well Installation and Boring Log • Well Development Record • Field Instrument Calibration Record 3.2 Laboratory Documentation A program of sample tracking and custody will be followed during sample handling activities in both field and laboratory operations. This program will be designed to ensure that each sample is accounted for at all times. The appropriate sampling and laboratory personnel will complete sample FDRs, chain -of -custody records, and laboratory receipt sheets. Additional information documented in the chain -of -custody may be required such as shipping information for samples sent by courier. Each sample container will typically have a label affixed to it and will be prepared prior to sampling to include the following information: • Sample location using a unique sample identification (i.e., AD2-2) • Date and time collected • Sampler identification • Analyses requested and applicable preservative The chain -of -custody (COC) will be initiated at the time of sample collection to provide record of the following: • Sample location (ID), number of containers corresponding to each sample, and sample handling procedures • Applicable preservatives and analyses requested • Date and time of sample collection • Name of sampler(s) and person(s) shipping the samples (if applicable) • Date and time samples were relinquished (e.g., picked up by lab courier) • If samples are shipped, a custody seal will be affixed to outside of each sample cooler • Name(s) of those responsible for receiving the samples at the laboratory CDCs will be prepared by the field sampler who will be responsible for the care and integrity of samples until they are properly relinquished to the laboratory or shipped. Sampling containers will be packed in coolers to reduce movement during transport to the laboratory. Styrofoam and bubble -pack may be used as packing materials, if needed. Ice will be placed in the coolers. Paperwork (COC forms) will be placed in a separate, re -sealable, water- tight plastic bag within the cooler. A temperature blank provided by the laboratory will be placed in each cooler, if required by the laboratory to verify the cooler was maintained at 4° Centigrade (C) [+/- 2°C] during sample transport. Custody seals will be placed across the lid and cooler - body interface prior to shipment to or pick up by the laboratory. 16 Duke Energy Carolinas, LLC I Cliffside Steam Station �� Groundwater Assessment Plan: Additional Assessment of Coal Ash Disposal Area Across the Broad River 3.3 Quality Control Field QC samples are not included specifically as laboratory QC samples but are analyzed when submitted to provide quality control data relative to the field sampling and sample management procedures. Data for field QC samples will be reported with associated samples. Field QA/QC samples will be analyzed for the same constituents as soil/ash or groundwater samples (Tables 1 and 2) unless otherwise noted. 3.3.1 Field Duplicates Field duplicates are two samples of the same matrix which are collected, to the extent possible, from the same location at the same time using the same techniques. Field duplicates provide information on the precision of the sampling and analysis process. Field duplicates will be collected at a frequency of one duplicate for every 20 samples collected (per media). If the total number of samples collected per media is less than 20, one field duplicate will be collected per day, per media of sampling. 3.3.2 Field Blanks Field blanks are prepared in the field to evaluate the potential for contamination of a sample by site contaminants from a source not associated with the sample collected (examples include dust or organic vapors). Analyte -free water provided by the laboratory will be brought to the field by the sampling crew and transferred to the proper sample container for shipment along with the other samples collected. One field blank sample will be collected per sampling day. 3.3.3 Data Validation Data validation describes an analyte -specific and sample -specific process of evaluating that a data set meets method, procedure, and contract requirements. Data review and validation will be performed in accordance with the United States Environmental Protection Agency (USEPA) Contract Laboratory Program (CLP) National Functional Guidelines for Superfund Organic Methods Data Review (USEPA 2014a) and the USEPA CLP National Functional Guidelines for Inorganic Data Review (USEPA 2014b). Analytical data will be reviewed and validated at a rate of 100 percent. Analytical results and qualifiers will be assessed using professional judgment to determine the final quality and usability of the data. Examples of data validation qualifiers include: U The analyte was analyzed for, but was not detected to, the method detection limit and was not quantifiable to the reporting limit. J The result is an estimated quantity. The associated numerical value is the approximate concentration of the analyte in the sample. J+ The result is an estimated quantity, but the result may be biased high. J- The result is an estimated quantity, but the result may be biased low. UJ The analyte was not detected; however, the result is estimated due to discrepancies in meeting certain analyte -specific quality control criteria. R The data are unusable. The sample results are rejected due to serious deficiencies in meeting QC criteria. The analyte may or may not be present in the sample. 17 Duke Energy Carolinas, LLC I Cliffside Steam Station Groundwater Assessment Plan: Additional Assessment of Coal Ash Disposal Area Across the Broad River Section 4 — Reporting As specified in the December 2, 2016, NCDEQ correspondence, the results of the work performed under this GAP Revision 1 will be reported to the NCDEQ DWR as a groundwater site assessment report (Report). The Report will present the findings of the ash and soil analyses; well installation; groundwater and surface water sampling activities and analyses; and will be supported by applicable figures (e.g., chembox, potentiometric surface, isoconcentration, cross-sections) and tables (e.g., well construction, groundwater elevation, and analytical tables) in a manner that provides an interpretation of site conditions. Per the December 2, 2016, letter, the report will also include the AMEC Foster Wheeler ash sampling results (map and tabular data). As discussed in Section 2, Duke Energy proposes to perform the activities described; to collect and analyze samples of ash, soil, groundwater, surface water; and to identify and sample AOWs as needed. After the initial review of the results from these activities, Duke Energy will evaluate if additional investigation, sampling, and analyses are needed. These additional assessment activities could include performing additional borings to collect soil samples at greater depths or installation of additional groundwater monitoring wells to delineate the horizontal and vertical extent of potential soil and groundwater contamination. Duke Energy proposes to communicate the results of the initial review with the NCDEQ ARO prior to conducting additional assessment activities. As discussed in Section 2.2.2.3, if groundwater monitoring well data indicate exceedances of the 2L Standards, the NCDEQ ARO will be notified so that deeper wells may be located and installed expeditiously to determine the vertical extent of groundwater contamination if determined to be necessary. 18 Duke Energy Carolinas, LLC I Cliffside Steam Station Groundwater Assessment Plan, Revision 1: Additional Assessment of Coal Ash Disposal Area Across the Broad River Section 5 — Proposed Schedule for Assessment The schedule for completion of this scope of work is contingent on NCDEQ approval of the proposed GAP Revision 1. HDR proposes the following schedule for the assessment tasks (Table 4) relative to receipt of authorization and Notice to Proceed (NTP) by Duke Energy procurement and subsequent to NCDEQ approval of the proposed GAP Revision 1. Table 4. Proposed Schedule for Additional Assessment of Coal Ash Disposal Areas across the Broad River Completion and Approval of Erosion and 6 weeks after notice to proceed and NCDEQ approval of Sediment Control Plans GAP Revision 1 Monitoring Well Installation Sample Collection and Analysis Data Validation 8 weeks after approval of erosion and sediment control ns 3 weeks after completion of well installation 2 weeks after receipt of laboratory analytical reports Submittal of Groundwater Site 8 weeks after completion of data validation Assessment Report 19 Duke Energy Carolinas, LLC I Cliffside Steam Station Groundwater Assessment Plan: FN Additional Assessment of Coal Ash Disposal Area Across the Broad River o �I\ N t/ --J o� I t ---- I 3I ' f 8 Ull I Legend I'I Areas of Interest D Stream —.Wetland r' V Ash Basin Waste Boundary 0 1,000 2.900 Feel FIGURE NOTES_ SITE LOCATION MAP I. AREAS OF INTEREST WERE DERIVED FROM A FIGURE OBTAINED FROM AMEC FOSTER W HEELER AND FIELD EXPLORATION ACTIEVATI NCONTPERFORMEDUR A DUR ENERGY 2. ELEVATION CONTOURS ARE FROM NO DOT AND BASED ON NC FLOODPLAIN MAPPING PROGRAM LIDAR ELEVATIONS. DUKE ENERGY CAROLINAS, LLC B. ORTHOPHOTOGRAPHY IS FROM NC ONEMAP CIS ONLINE SERVICE. F)l /+ �+ (� CLIFFSIDE STEAM STATION 6. PRIVATE WELL LOCATIONS ARE APPROXIMATE. 5. ASH BASIN WASTE BOUNDARIES ARE APPROXIMATE. 6. STREAMS AND WE LANDS SHOWN SOUTH OF THE BROAD RIVER ARE CURRENTLY UNDER REVIEW, THE AREAS SHOWN CLEVELAND COUNTY AND RUTHERFORD COUNTY, HAVE BEEN PROVIDED BY AMEC ON MAY 29, 2015. 7. STREAMS AND WETLANDS SHOWN NORTH OF THE BROAD RIVER ARE CURRENTLY UNDER REVIEW. THEAREAS SHOWN NORTH CAROLINA HAVE BEEN PROVIDED BY AMEC ON SEPTEMBER 16, 2016 DATE MAY 2017 FIGURE 1 EM Legend Proposed Shallow Monitoring Well • Proposed Soil Boring • Proposed Surface Water Sample WELL PLACEMENT NOTES: • Sample Locations AMSC 2016 1. PREVIOUS ADI -1 LOCATION WAS INVESTIGATED WITH ASHOVEL AND NO ASH WAS P ( ) ENCOUNTERED AT THE LOCATION Areas of Interest 2. PREVIOUS AD2-1 LOCATION WAS NOT ACCESSIBLE DUE TO ASH MOUNDS/TOPOGRAPHY Stream 3. PREVIOUS AD3-1 LOCATION WAS DIRECTLY UNDER OVERHEAD TRANSMISSION LINES, AS IS THE REMAINDER OF ASH AREA 3; AD3-2 WAS RELOCATED DOWNGRADIENT OF AREA 3 NO WATER SUPPLY WELLS ARE LOCATED WITHIN THE EXTENT OF THIS MAP. FIGURE NOTES: 1. SAMPLE LOCATIONS AND AREAS OF INTEREST WERE DERIVED FROM A FIGURE OBTAINED FROM AMEC FOSTER WHEELER. 2. ELEVATION CONTOURS ARE FROM TOPOGRAPHIC MAP GENERATED BY WSP FROM AERIAL IMAGERY COLLECTEDAPRIL 2014. 3. ORTHOPHOTOGRAPHY IS FROM NC ONEMAP GIS ONLINE SERVICE. 4. STREAM LOCATION PROVIDED BYAMEC ON SEPTEMBER 16, 2016. 0 0 1 "= 150' SCALE (FEET) 75 0 75 150F)l °tom •- MaFii � IfU C�G�C G� NI PROPOSED MONITORING WELL, SURFACE WATER DATE SAMPLE, AND SOIL BORING LOCATION MAP MAY 2017 DUKE ENERGY CAROLINAS, LLC CLIFFSIDE STEAM STATION FIGURE CLEVELAND COUNTYAND RUTHERFORD COUNTY, 2 NORTH CAROLINA FLUSH -MOUNT STEEL WELL MANHOLE COVER PROTECTIVE WELL VAULT (WITH WELL TAG 10 ATTACHED TO CONCRETE IN MANHOLE 2'x2'X4' CONCRETE WELL PAD LOCKABLE WELL PLUG EXISTING GROUND WELL TAG 1D ATTACHED o STEEL MANHOLE SKIRT PORTLAND CEMENT AND BENTONITE GROUT MIX TO SURFACE a WELL CASING (2 -INCH DIA. SCH. 40 PVC) --__8-INCH OR 10 -INCH DIA BOREHOLE (FORDEEP WELLS) OUTER CASINGINCH (H. CONCRETE OR SAND (WITH THE TOP ESC40 PVC TYPICAL FLUSH—MOUNT WELL COVER SCALE: NTS 4' SQUARE PROTECTIVE CASING (WITH LOCKING COVER AND WELL TAG ID ATTACHED) CAP I EXISTING GROUND SUR ACES 1�{ �� �j/ PVC SER CONCRETE F AND STEEL BOLLARD TYPICAL PROTECTIVE BOLLARDS (PROFILE) SCALE: NTS 4 -FT WEEP HOLE :ONCRETE PAD :RETE WELL PAD GROUND ENT AND BENTONITE SURFACE SCH. 40 PVC) EAL (CHIPS OR PELLETS) EEN AND PRE -PACK SAND (20x40) (#2) SCH. 40 PVC SCREEN SLO WITH PRE -PACKED (20x 0) -- `THREADED PVC CAP TYPICAL SHALLOW MONITORING WELL (Single Cased) SCALE: NTS NOTES: 1. MONITORING WELLS WILL BE CONSTRUCTED IN ACCORDANCE WITH 15A NCAC 02C.0108 STANDARDS OF CONSTRUCTION: WELLS OTHER THAN WATER SUPPLY. 2. WELL TAG IDS TO BE ATTACHED TO WELL PROTECTIVE COVER WITH MECHANICAL RIVETS. 3. PROTECTIVE BOLLARDS (CONE -TAPERED, FILLED WITH CONCRETE, AND PAINTED YELLOW) ARE TO BE INSTALLED AS NECESSARY. 4. SLOPE 2'X 2' CONCRETE PAD SURFACE UPWARD TO PROTECTIVE COVER TO PREVENT PONDING WATER. S. WELL ID TO BE ETCHED IN 2'X 2' CONCRETE PAD. 6. ALL CONSTRUCTION MEASUREMENTS ARE APPROXIMATE. F)2 SHALLOW MONITORING WELL CONSTRUCTION DETAILS DUKE ENERGY CAROLINAS, LLC CLIFFSIDE STEAM STATION CLEVELAND COUNTY AND RUTHERFORD COUNTY, NORTH CAROLINA DATE MAY 2017 FIGURE 3 PROTECTIVE WELL VAULT WITH LOCKING COVER AND WELL TAG 1D ATTACHED (2 -FT MIN. HEIGHT) a 2'x2'X4' CONCRETE WELL PAD PROTECTIVE BOLLARD FILLED WITH CONCRETE OR SAND (WITH THE TOP Lo 6-8' CAPPED WITH CONCRETE) AND PAIN)YELLOW TYPICAL PROTECTIVE BOLLARDS (PLAN) SCALE: NTS WEEP HOLE :ONCRETE PAD :RETE WELL PAD GROUND ENT AND BENTONITE SURFACE SCH. 40 PVC) EAL (CHIPS OR PELLETS) EEN AND PRE -PACK SAND (20x40) (#2) SCH. 40 PVC SCREEN SLO WITH PRE -PACKED (20x 0) -- `THREADED PVC CAP TYPICAL SHALLOW MONITORING WELL (Single Cased) SCALE: NTS NOTES: 1. MONITORING WELLS WILL BE CONSTRUCTED IN ACCORDANCE WITH 15A NCAC 02C.0108 STANDARDS OF CONSTRUCTION: WELLS OTHER THAN WATER SUPPLY. 2. WELL TAG IDS TO BE ATTACHED TO WELL PROTECTIVE COVER WITH MECHANICAL RIVETS. 3. PROTECTIVE BOLLARDS (CONE -TAPERED, FILLED WITH CONCRETE, AND PAINTED YELLOW) ARE TO BE INSTALLED AS NECESSARY. 4. SLOPE 2'X 2' CONCRETE PAD SURFACE UPWARD TO PROTECTIVE COVER TO PREVENT PONDING WATER. S. WELL ID TO BE ETCHED IN 2'X 2' CONCRETE PAD. 6. ALL CONSTRUCTION MEASUREMENTS ARE APPROXIMATE. F)2 SHALLOW MONITORING WELL CONSTRUCTION DETAILS DUKE ENERGY CAROLINAS, LLC CLIFFSIDE STEAM STATION CLEVELAND COUNTY AND RUTHERFORD COUNTY, NORTH CAROLINA DATE MAY 2017 FIGURE 3 Duke Energy Carolinas, LLC I Cliffside Steam Station = =3 Groundwater Assessment Plan: J_ Ty Additional Assessment of Coal Ash Disposal Area Across the Broad River Appendix A "Additional Site Assessment Required" letter, July 8, 2016 "Conditional Additional Site Assessment Approvals" letter, November 23, 2016 "Correction to the Conditional Additional Site Assessment Approvals", dated December 2, 2016 "Extension Request — Additional Areas Assessment", dated February 27, 2017 "Additional Site Assessment", dated April 19, 2017 Water Resources ENVIRONMENTAL QUALITY PAT MCCRORY DONALD R. VAN DER VAART Secretary S. JAY ZIMMERMAN Director July 8, 2016 Mr. Harry Sideris Senior Vice President Environment, Health, and Safety Duke Energy 526 South Church Street Mail Code EC3XP Charlotte, NC 28202 Subject: Additional Site Assessment Required Jaynes E. Rogers Energy Complex (Formerly Cliffside Steam Station) NPDES Permit NCO005088 — Rutherford and Cleveland Counties Roxboro Steam Electric Plant NPDES Permit NCO003425 — Person County W. H. Weatherspoon Power Plant NPDES Permit NCO005363 — Robeson County Dear Mr. Sideris: The North Carolina Department of Environmental Quality's Division of Water Resources (DWR) requests Duke Energy (Duke) provide data and conduct additional site assessment as needed to characterize the distribution of coal ash residuals (CCR) at confirmed and potential coal ash disposal areas at the James E. Rogers Energy Complex, Roxboro Steam Electric Plant, and the W.H. Weatherspoon Plant. Descriptions and approximate locations of these areas are provided below. The additional assessments shall be included as part of the on-going Comprehensive Site Assessments (CSAs) for each of the subject facilities. Please be advised that these areas are to be included in an updated Groundwater Assessment Plan (GAP) that conforms with the North Carolina Department of Environment and Natural Resources Notice of Regulatory Requirements letter dated August 13, 2014 and Comprehensive Coal Ash Management Act (CAMA). Site activities shall follow the requirements under 15A NCAC 02L .0106(8). An assessment of surface water quality for those areas that have impounded or flowing water shall also be conducted. Arca(s) of Wetness (AOW) related to these disposal areas should be assessed pursuant to CAMA §130A-309.212. State of North Carolina I Environmental Quality j Water Resources 1611 Mail service Center I Raleigh, North Carolina 27699-1611 919 707 9000 Additional Site Assessment Required July 8, 2016 The results of the characterization conducted to date in addition to pertinent historical records and detailed plans for additional site assessments must provide adequate detail to allow technical review of the proposed actions shall be provided to the DWR. GAPs are due to the DWR Central Office and the appropriate DWR Regional Office no later than August 19, 2016. Results of related investigations may be submitted as a CSA Addendum Report at a later date. In addition to performing site assessment activities, facility site maps must be updated with the revised waste boundaries and proposed compliance boundaries established according to 15A NCAC 02L Section .0107. A letter requesting the approval of the new compliance boundaries shall be submitted to the appropriate DWR Central Office later than August 19, 2016. The following are background information and approximate locations of the identified areas at each of the subject sites requiring additional assessment: James E. Rogers Energy Complex On November 16, 2015, Duke communicated orally to DWR that a historical coal ash disposal area located was identified just north of the Broad River and west of the switchyard at the James E. Rogers Energy Complex. Duke staff estimated the area to be approximately 3 acres in size, but stated that the full extent of the area is unknown. The approximate location of the area is shown below encircled. This area was not addressed in the Groundwater Assessment Plan (GAP), Comprehensive Site Assessment (CSA) report, or Corrective Action Plans (CAPS) submitted to DWR. Characterization of CCR within the footprint of this disposal area was confirmed by Duke; however, no data related to this disposal area has been provided to DWR at this time. 21 Page Additional Site Assessment Required July 8, 2016 Roxboro Steam Electric Plant Area 1 — This area was discovered by Duke and presented orally to DWR during a joint meeting on January 14, 2016. This area is located directly cast of the East Ash Basin and was subsequently named by DWR the "Unnamed Eastern Extension Basin" for purposes of prioritization ranking according to the Coal Ash Management Act. This area shall also include the discharge canal that runs north along the eastern side of the East Ash Basin. This area was not addressed in the GAP, CSA report, or CAPS submitted to DWR. The approximate location of the area is shown below encircled. Alp Area 2 — This area is located directly south of the West Ash Basin and encompasses the three "fingers" of the dammed watershed and the drainage canal that runs north along the west side of the West Ash Basin. The drainage canal should be assessed for the presence of coal ash and surface water standards. Based on site visits and information presented in the CSA and CAP reports, DWR suspects that coal ash may be present in this area. This area was not addressed in the GAP, CSA report, or OAPs submitted to DWR. The approximate location of the areas is shown below encircled. 31 Page Additional Site Assessment Required July S, 2016 W. H. Weatherspoon Power Plant Duke informed DWR orally at a joint meeting on October 21, 2015, that the cooling pond may contain coal ash. Also, according to the CSA Report for the facility, the cooling pond is part of the treatment process before the effluent is discharged through the NPDES outfall. This area was not addressed in the GAP, CSA report, or CAPs submitted to DWR; however, Duke has stated that an investigation is currently underway. The approximate location of the area is shown below encircled. 41 Page Additional Site Assessment Required July 8, 2016 PROPERTY 6UNOAki' . ' - ANC • `^.600'COYPLUINCE e0UNDARY WASTE 1 I BOUNDARY 4 I. l If you have any questions, please feel free to contact Stege Lanter at (919) 807-6444. Sincerely, S. y erman�PG., Director Division of Water Resources cc: Landon Davidson — Asheville Regional Office Supervisor Danny Smith — Raleigh Regional Office Supervisor Belinda Henson — Fayetteville Regional Office Supervisor Jeff Poupart, DWR Water Quality Permitting Section Chief WQROS Central File Copy 51Page F Water Resources ENVIRONMENTAL OUAL$TY PAT MCCRORY [tll�sE DONALD R, VAN DER VAART sew -wary S. JAY ZIMMERMAN Ylnrerrar November 23, 2016 Mr. Harry Sideris Senior Vice President Environment, Health, and Safety Duke Energy 526 South Church Street Mail Code EC3XP Charlotte, NC 28202 Subject: Conditional Additional Site Assessment Approvals James E. Rogers Energy Complex (Formerly Cliffside Steam Station) NPDES Permit NCO005088 — Rutherford and Cleveland Counties Roxboro Steam Electric Plant NPDES Permit NCO003425 — Person County W. H. Weatherspoon Power Plant NPDES Permit NCO005363 — Robeson County Dear Mr. Sideris: On August 18, 2016, the North Carolina Department of Environmental Quality (DEQ) received the proposed plans to conduct additional assessment activities for the subject facilities per our request letter dated July 8, 2016. Based on a review of the plans and other information received by DEQ Regional [Office staff, conditional approval of the plans is granted. DEQ's approval is contingent upon the following site specific conditions: James E. Rogers Enemy Complex • In the groundwater assessment report that will be provided following this investigation, please include the AMEC Foster Wheeler ash sampling results (map and tabular data). • If monitoring well data indicate exceedances of the 15A NCAC 02L groundwater standards, notify DEQ's Asheville Regional Office immediately so that deeper wells may be located and installed expeditiously. The deeper well(s) would be needed to determine the vertical extent of groundwater contamination, DEQ concurs with the proposed boring/well locations, of which six are ash -related and one is background. State of North Carolina I Environmental Quality N Water Resources 1611 Mail service. Center I Raleigh, North Carolina 27699-1611 919 707 9000 DEQ concurs with the sample depth intervals for purposes of Unified Soil Classification System descriptions. • Please revise the soil/ash sampling requirements as follows. For each of the six ash -related boring locations, a lab analysis (constituents are listed in Table 2) should be conducted for all sampled depth intervals that contain visual evidence of ash. If 4 or more intervals contain ash, conduct a lab analysis only on the shallowest ash interval, the deepest ash interval, and a composite of the remaining ash intervals, for a total of three ash lab analyses. DEQ concurs with the 5 -foot minimum thickness criterion to determine when to analyze variations in ash type (fly or bottom). For soil sampling and lab analysis at each of the six ash -related boring locations, DEQ concurs with the two proposed sample intervals: 2 feet below the ash/soil interface and 8 to 10 feet below the ash/soil interface. • For SPLP analysis at each of the six ash -related boring locations, please conduct an analysis on o a) the sampled ash interval with the highest concentration of arsenic, selenium, and strontium among all sampled ash intervals at that location, and o b) a sample composited from the two sampled soil intervals at that location. • For soil sampling and analysis at the background boring location, please collect: o a) one shallow soil sample at a depth that approximates the general depth of most of the shallow soil samples from the other six borings, o b) one deeper soil sample at a depth that approximates the general depth of most of the deeper soil samples from the other six borings, and o e) one SPLP sample that is a composite of the shallow and deeper intervals in a) and b) above. Please revise Section 2.2.3 to read that if inaccessible from the bank, a boat should be used to collect three surface water samples upstream, adjacent to, and downstream of the AOIs. These samples should be collected immediately adjacent to the bank during conditions that approximate low or baseflow to the maximum extent possible and at least 5 days after a previous rain event of any magnitude. Contact DEQ's Asheville Regional Office if this request becomes difficult to meet based on weather conditions. Antecedent rainfall (prior 5 days and prior 48 hours) should be provided, along with its measurement location, as a footnote in surface water results table. Roxboro Steam Electric Plant In the groundwater assessment report that will be provided following this investigation, please identify on a map all private supply wells within a �/z mile radius of an assumed compliance boundary around the study area, monitor well locations, any areas of wetness, and surface water features. • DEQ recommends additional monitoring wells to be installed in each water -bearing hydrostratigraphic unit at a nested well location south east of existing well MW- 12BR. • DEQ recommends relocating any proposed sampling point locations where insufficient sediment recovery is an issue. W. H. Weatherspoon Power Plant • In the groundwater assessment report that will be provided following this investigation, please identify on a map all private supply wells within a'/a mile radius of an assumed compliance boundary around the study area, monitor well locations, any areas of wetness, and surface water features. DEQ recommends moving the proposed sample location JC -1 to the drainage feature before it enters the creek (coordinates N 34.5902, W 78.9660) In response to your "Proposed Waste and Compliance Boundaries" letter dated August 19, 2016, DEQ cannot approve the proposed revised compliance boundary locations for the subject facilities at this time. DEQ will provide correspondence and direction regarding this issue in the near future. Submit the findings of the site assessments for each subject facility as a groundwater site assessment report. The respective site assessment reports shall include figures, tables, cross- sections, and maps in a manner that provides an interpretation of site conditions. In each report, include a map that shows all private supply wells, monitoring well locations, any areas of wetness, and surface water features within a I/2 mile radius of a previously established compliance boundary around the study area. Reports submitted in a data summary format will not be approved as an acceptable documentation of findings. Submit site assessment reports for each facility by March 31, 2017. Please begin implementing these plans immediately to include the conditional items listed. For general questions, contact Steve Lanter at (919) 507-6444. For more specific questions, please contact our Regional staff listed below: • James E. Rogers Energy Complex: Ted Campbell at (828) 296-4500 • Roxboro Steam Electric Plant: Eric Rice at (919) 791-4200 • W. H. Weatherspoon Power Plant: Kent White at (910) 433-3300 Sincerely, S. Jay immerman, P.G., Director Division of Water Resources cc: ARO, FRO, & RRO WQROS Regional Supervisors and Assistant Supervisors WQROS Central File Copy Wa ter Resources ENVIRONMENTAL QUALITY PAT MCCRORY DONALD R, VAN DER VAART ,1'rcrerar}, S. JAY ZIMMERMAN !hector December 2, 2016 Mr. Harry Sideris Senior Vice President Environment, Health, and Safety Duke Energy 526 South Church Street Mail Code EC3XP Charlotte, NC 28202 Subject: Correction to the Conditional Additional Site Assessment Approvals James E. Rogers Energy Complex (Formerly Cliffside Steam Station.) NPDES Permit NCO005088 — Rutherford and Cleveland Counties Roxboro Steam Electric Plant NPDES Permit NCO003425 — Person County W. H. Weatherspoon Power Plant NPDES Permit NCO005363 — Robeson County Dear Mr. Sideris: On November 22, 2016, the North Carolina Department of Environmental Quality (DEQ) sent a letter to your attention regarding the subject facilities in which an error was noted on page 3 in the next to last paragraph. This letter is a corrected version that supersedes the before -mentioned letter dated November 22, 2016. On August 18, 2016, the DEQ received the proposed plans to conduct additional assessment activities for the subject facilities per our request letter dated July 8, 2016. Based on a review of the plans and other information received by DEQ Regional Office staff, conditional approval of the plans is granted. DEQ's approval is contingent upon the following site specific conditions: James E. Rogers Energy Complex • In the groundwater assessment report that will be provided following this investigation, please include the AMEC Foster Wheeler ash sampling results (map and tabular data). s if monitoring well data indicate exceedances of the 15A NCAC 02L groundwater standards, notify DEQ's Asheville Regional Office immediately so that deeper wells may be located and installed expeditiously. The deeper well(s) would be needed to determine the vertical extent of groundwater contamination. State of North Carolina I Environmental Quality I Water Resources 1611 Mail service Center I Raleigh, North Carolina 27699-1611 919 707 9000 • DEQ concurs with the proposed boring/well locations, of which six are ash -related and one is background. • DEQ concurs with the sample depth intervals for purposes of Unified Soil Classification System descriptions. Please revise the soil/ash sampling requirements as follows. For each of the six ash -related boring locations, a lab analysis (constituents are listed in Table 2) should be conducted for all sampled depth intervals that contain visual evidence of ash. If 4 or more intervals contain ash, conduct a lab analysis only on the shallowest ash interval, the deepest ash interval, and a composite of the remaining ash intervals, for a total of three ash lab analyses. DEQ concurs with the 5 -foot minimum thickness criterion to determine when to analyze variations in ash type (fly or bottom). + For soil sampling and lab analysis at each of the six ash -related boring locations, DEQ concurs with the two proposed sample intervals: 2 feet below the ash/soil interface and 8 to 10 feet below the ash/soil 'interface. • For SPLP analysis at each ofthe six ash -related boring locations, please conduct an analysis on o a) the sampled ash interval with the highest concentration of arsenic, selenium, and strontium among all sampled ash intervals at that location, and o b) a sample composited from the two sampled soil intervals at that location. • For soil sampling and analysis at the background boring location, please collect: o a) one shallow soil sample at a depth that approximates the general depth of most of the shallow soil samples from the other six borings, o b) one deeper soil sample at a depth that approximates the general depth of most of the deeper soil samples from the other six borings, and o c) one SPLP sample that is a composite of the shallow and deeper intervals in a) and b) above. • Please revise Section 2.2.3 to read that if inaccessible from the bank, a boat should be used to collect three surface water samples upstream, adjacent to, and downstream of the AOIs. These samples should be collected immediately adjacent to the bank during conditions that approximate low or baseflow to the maximum extent possible and at least 5 days after a previous rain event of any magnitude. Contact DEQ's Asheville Regional Office if this request becomes difficult to meet based on weather conditions. Antecedent rainfall (prior 5 days and prior 48 hours) should be provided, along with its measurement location, as a footnote in surface water results table. Roxboro Steam Electric Plant • In the groundwater assessment report that will be provided following this investigation, please identify on a map all private supply wells within a 'l2 mile radius of an assumed compliance boundary around the study area, monitor well locations, any areas of wetness, and surface water features. DEQ recommends additional monitoring wells to be installed in each water -bearing hydrostratigraphic unit at a nested well location south east of existing well MW-12BR. DEQ recommends relocating any proposed sampling point locations where insufficient sediment recovery is an issue. W. H. Weatherspoon Power Plant • In the groundwater assessment report that will be provided following this investigation, please identify on a map all private supply wells within a /2 mile radius of an assumed compliance boundary around the study area, monitor well locations, any areas of wetness, and surface water features. DEQ recommends moving the proposed sample location JC -1 to the drainage feature before it enters the creek (coordinates N 34.5902, W 78.9660) In response to your "Proposed Waste and Compliance Boundaries" letter dated August 19, 2016, DEQ cannot approve the proposed revised compliance boundary locations for the subject facilities at this time. DEQ will provide correspondence and direction regarding this issue in the near future. Submit the findings of the site assessments for each subject facility as a groundwater site assessment report. The respective site assessment reports shall include figures, tables, cross- sections, and maps in a manner that provides an interpretation of site conditions. In each report, include a map that shows all private supply wells, monitoring well locations, any areas of wetness, and surface water features within a'/2 mile radius of a previously established compliance boundary around the study area. Reports submitted in a data summary format will not be approved as an acceptable documentation of findings. Submit site assessment reports for each facility by March 31, 2017. Please begin implementing these plans immediately to include the conditional items listed. For general questions, contact Steve Lanter at (919) 807--6444. For more specific questions, please contact our Regional staff listed below: • James E. Rogers Energy Complex: Ted Campbell at (828) 296-4500 • Roxboro Steam Electric Plant: Eric Rice at (919) 791-4200 • W. H. Weatherspoon Power Plant: Kent White at (910) 433-3300 Sincerely, S. Jay'Zimmerman, P.G., Director Division of Water Resources cc: ARO, FRO, & RRO WQROS Regional Supervisors and Assistant Supervisors WQROS Central File Copy Water Resources Enviroinnental Quality February 27, 2017 D. Edwin Sullivan Director, Waste and Groundwater Programs Environmental, Health & Safety Duke Energy 526 South Church Street Mail Code EC 13K Charlotte, North Carolina 28202 ROY COOPER Governor MICHAEL S. REGAN Secretaq S. JAY ZIMMERMAN Director Subject: Extension Request — Additional Areas Assessment James E. Rogers Energy Complex (Formerly — NPDES No. NCO0005088 — Rutherford and Cleveland Counties Roxboro Steam Electric Plant — NPDES No. NCO003425 — Person County W.H. Weatherspoon Power Plant — NPDES No. NCO005363 — Gaston County Dear Mr. Sullivan: On August 18, 2016, the North Carolina Department of Environmental Quality (DEQ) received proposed plans from Duke Energy to conduct additional assessment activities for the James E. Rogers Energy Complex (Rogers), Roxboro Steam Electric Plant (Roxboro), and W.H. Weatherspoon Power Plant (Weatherspoon) as requested by the Department. Based on a review of the plans and other inforination received by DEQ Regional Office staff, conditional approval of the plans was granted based on site-specific provisions in our November 23, 2016 letter, which was revised on December 2, 2016. In granting conditional approval, the DEQ stipulated a deadline of March 31, 2017 for submittal of site assessment reports for each facility. In a January 27, 2017 letter to DEQ, Duke Energy requested a 60 -day extension for the Additional Areas Site Assessment Plan at Roxboro and Weatherspoon, and an extension at Rogers until all ash is removed from the ash basin. DEQ grants an extension as requested to complete activities related to the site assessments for the subject facilities contingent on updated status reports provided to the Regional Offices at the first of each month. These updated status reports will consist of documentation of permit issues, schedules for sample collection and analysis, and time estimates for reporting. Any problems that may impact meeting the revised timeframe for report completion must be communicated to the respective Regional Offices_ If you have any questions regarding this letter, please feel free to contact Steve Lanter (Central Office) at 919-807-6444. For more specific questions, please contact our Regional staff listed below; James E. Rogers Energy Complex: Ted Campbell at (828) 296-4500 • Roxboro Steam Electric Plant: Eric Rice at (919) 791-4200 W. H. Weatherspoon Power Plant: Dent White at (910) 433-3300 'Nsathirry iC'omp )rr,!�"- State of North Carolina I Environmental Quality I Division of Water Resources Water Quality Regional Operations section 1636 Mail Service Center I Raleigh, North Carolina 27699-1636 919-707-9129 Sincerely, 4 S. Z ennan, P.G., Director Division of Water Resources cc: WQROS Asheville, Raleigh, and Fayetteville Regional Office Supervisors WQROS Central File Copy Page 2 of 2 w April 19, 2017 Mr. S. Jay Z mmerman. Dlrectar Division of Water Resoarcua North Carolina Department of Environmental Quality 1611 Mail Service Center Raleigh, North Carolina 27699-1611 En-ironmepit»I, m. -h i F. szrot, 526 South CMurcn Street; RI&I Uwd-c EC 1 A Chaflatte, North Carolina 20zuz SebjGzt: Add;t;unal Site Aaaessment James E. tiogers Energy Complex (f%rmurly Cliffside Stamm Station) Muurasboro, Ratharfurd and Cleveland Counties. North Carolina NPDES Permit NC000arjvaa Dear Mr. Zimmerman: On Fobroary 27, 2017 Duke E=nergy (Duke) receiva0 an extension from the North Carolina Department of Environmental tonality Di,,kjun of Water Resuurcu5 (DWR) for additiulial assossrrlent activities at the James E. Rugars Energy Complex (Rogers) until all ash was removed from the area across the Broad River near the Unit 5 S.,ituhynrd. UpVin further evaluation, Duke has decided to pruueed ,with a55e55,iant of the area prior to making a determination un ash removal. Farthermure, additional asn was discovered beneath the Unit 5 Switchyard east of the original assessmurlt area. Thio EVanded ash area ,will be incorporated Into a ru,risad VYurk plan arid 5obmittcd to DWR no later than May 12, tet; i t. If you have questions uonuorning this Sitia, you may contact Ryan Ccup at 980-373-2779. Sincerely, D. Edwin M. Sullivan Director, Waste & Groundwater Programs En„irunrrluntel, Health, & Safety cc NCDEQ (electronic): Ted Campbell - NCDE_u Ashu,,illu Regional Office Lai dun Davidson — NCDEQ Asheville Regio, al Office Steve Lanter - NCDCQ Raleigh Eric Smith - NCDEU Raleigh cc Dake (electronic): Ryan Czop Duke Energy Carolinas, LLC I Cliffside Steam Station _ Groundwater Assessment Plan: Additional Assessment of Coal Ash Disposal Area Across the Broad River Appendix B Low Flow Sampling Plan, Duke Energy Facilities, Ash Basin Groundwater Assessment Program, North Carolina, June 10, 2015 DUKE Low Flow Sampling Plan Energy Facilities Ash Basin Groundwater Assessment Program Duke Energy I Low Flow Groundwater Sampling Plan Table of Contents 1 -.,DUKE `t' ENERGY TABLE OF CONTENTS LowFlow Sampling Plan.......................................................................................................1 1.0 PURPOSE...............................................................................................................................1 2.0 GENERAL CONSIDERATIONS.............................................................................................1 3.0 PROCEDURES.......................................................................................................................2 3.1 Pre -Job Preparation.............................................................................................................2 3.2 Water -Level Measurements.................................................................................................3 3.3 Well Purging........................................................................................................................4 3.3.1 Low -Flow Well Purging............................................................................................4 3.3.2 Volume -Averaging Well Purging..............................................................................8 3.4 Sampling.......................................................................................................................10 3.4.1 Low -Flow Sampling...............................................................................................10 3.4.2 Sampling after Volume -Averaging Purge...............................................................11 3.5 Sample Handling, Packing, and Shipping.....................................................................11 3.5.1 Handling................................................................................................................11 3.5.2 Sample Labels.......................................................................................................11 3.5.3 Chain -of -Custody Record......................................................................................12 3.6 Field Quality Control Samples.......................................................................................12 3.7 Field Logbook Documentation.......................................................................................13 3.8 Decontamination and Waste Management...................................................................14 4.0 REFERENCES.....................................................................................................................14 APPENDIX A -Decontamination of Equipment SOP...................................................................15 1.0 Purpose & Application......................................................................................................16 2.0 Equipment & Materials..........................................................................................................16 3.0 Procedure.............................................................................................................................16 3.1 Decontamination of Non -Disposable Sampling Equipment..........................................16 3.2 Decontamination of Field Instrumentation....................................................................16 3.3 Decontamination of Groundwater Sampling Equipment...............................................17 3.4 Materials from Decontamination Activities....................................................................17 APPENDIX B -Sampling Equipment Check List - Table 1 ..........................................................18 APPENDIX C -Field Logbook/Data Sheets.................................................................................20 Duke Energy I Low Flow Groundwater Sampling Plar 1.0 PURPOSE ;��DUKE V ENERGY. 1.0 PURPOSE The purpose of this low flow sampling plan is to establish a standard operating procedure (SOP) to describe collection procedures for groundwater samples from monitoring wells using low -flow purging and sampling techniques or by the volume - averaged purging and sampling method at Duke Energy Ash Basin Groundwater Assessment Program facilities. 2.0 GENERAL CONSIDERATIONS Potential hazards associated with the planned tasks shall be thoroughly evaluated prior to conducting field activities. The Ready -To -Work Plan developed for each facility provides, among other items, a description of potential hazards and associated safety and control measures. Sampling personnel must wear powder -free nitrile gloves or equivalent while performing the procedures described in this SOP. Specifically, gloves must be worn while preparing sample bottles, preparing and decontaminating sampling equipment, collecting samples, and packing samples. At a minimum, gloves must be changed prior to the collection of each sample, or as necessary to prevent the possibility of cross -contamination with the sample, the sample bottles, or the sampling equipment. Field sampling equipment shall be decontaminated in accordance with the Decontamination of Equipment SOP (Appendix A) prior to use. Although sampling should typically be conducted from least to most impacted location, field logistics may necessitate other sample collection priorities. When sampling does not proceed from least to most impacted location, precautions must be taken to ensure that appropriate levels of decontamination are achieved. An example of equipment needed to properly conduct low -flow purging and sampling or volume- averaged groundwater purging and sampling is listed on the example checklist in Table 1 (Appendix B). If a portable generator is used to power the purge pump, it shall be attempted to be located downwind of the well being sampling to avoid cross -contamination of the sample with exhaust from the generator motor. Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES ;,f,,DUKE V ENFRGv. 3.0 PROCEDURES The following sections describe the general operating procedures and methods associated with groundwater sampling. Any variation in these procedures must be approved by the Project Manager (PM) and Quality Assurance/Quality Control (QA/QC) Lead and must be fully documented. Field work cannot progress until deviations are approved or resolved. 3.1 Pre -Job Preparation The information listed below may be reviewed prior to sampling activities, if available, and can be beneficial on-site for reference in the field as necessary: • A list of the monitoring wells to be sampled; • Information describing well location, using site-specific or topographic maps or Global Positioning System (GPS) coordinates and descriptions tied directly to prominent field markers; • A list of the analytical requirements for each sampling location; • Boring logs and well construction details, if available; • Survey data that identify the documented point of reference (V -notch or other mark on well casing) for the collection of depth -to -groundwater and total well depth measurements; • Previous depth -to -groundwater measurements; • Previous pump placement depths (dedicated pumps as well as portable pumps) for each sampling location, if available; • Previous pump settings and pumping and drawdown rates, if available; and • Previous analytical results for each monitoring well, if known. The information above is useful when determining the sampling order, pump intake depth, and purge and recharge rates, and can facilitate troubleshooting. The following activities should be completed prior to mobilizing to the site: • Obtain equipment necessary for completing the sampling activities (see the example checklist in Table 1). • Ensure appropriate laboratory -provided bottles are available for both the required analyses and for QC samples and that there has been thorough coordination with the analytical laboratory. E Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES &,L)uKE '*' ENERGY. • Obtain site-specific maps or GPS coordinates showing clearly marked monitoring well locations or groundwater sample points. • Review the project work control documents such as the Ready -To -Work Plan, and appropriate SOPs in an effort to determine project -specific sampling requirements, procedures, and goals. • Verify that legal right -of -entry has been obtained and site access has been granted, where required. • Instruct the field team to avoid discussing project data with the public and to refer questions to the Project Manager. 3.2 Water -Level Measurements Prior to pump placement, an initial depth -to -water level and total well depth should be measured. For monitoring wells screened across the water table, this measurement shall be used to determine the required depth to the pump intake (typically, approximately the mid -point of the saturated screen length for low -flow purging and sampling). The procedure for measuring water levels may include the following: 1) Inspect the well head area for evidence of damage or disturbance. Record notable observations in the field logbook. 2) Carefully open the protective outer cover of the monitoring well noting the presence of bee hives and/or spiders, as these animals are frequently found inside well covers. Remove any debris that has accumulated around the riser near the well plug. If water is present above the top of the riser and well plug, remove the water prior to opening the well plug. Do not open the well until the water above the well head has been removed. 3) If practical, well plugs shall be left open for approximately five minutes to allow the static water level to equilibrate before measuring the water level (if well plugs are vented, then a waiting period is not applicable). 4) Using an electronic water -level indicator accurate to 0.01 feet, determine the distance between the established point of reference (usually a V -notch or indelible mark on the well riser) and the surface of the standing water present in the well. Record these data in the field logbook. Repeat this measurement until two successive readings agree to within 0.01 feet. 5) Using an electronic water -level indicator accurate to 0.01 feet, determine the distance between the established point of reference (usually a V -notch or indelible mark on the well riser) and the bottom of the well. Note that there should not be considerable slack in the water -level indicator cable. Record these data in the field logbook. Repeat this measurement until two successive readings agree to within 0.01 feet. 6) If the monitoring well has the potential to contain non -aqueous phase liquids (NAPLs), probe the well for these materials using an optical interface probe. These wells will be attempted to be identified by the Project Manager prior to 3 Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES ;,f,,DUKE V I ENERGY. mobilizing to the well. If NAPL is present, consult the Project Manager for direction on collecting samples for analysis. In general, do not collect groundwater samples from monitoring wells containing NAPL. 7) Decontaminate the water -level indicator (and interface probe, if applicable) and return the indicator to its clean protective casing. 3.3 Well Purging Wells must be purged prior to sampling to ensure that representative groundwater is obtained from the water -bearing unit. If the well has been previously sampled in accordance with this sampling plan, then the depth to the pump intake and the pumping rates should be duplicated to the extent possible during subsequent sampling events. Section 3.3.1 provides a description of low -flow well purging, and Section 3.3.2 provides a description of volume -averaging well purging (in the case it's needed). 3.3.1 Low -Flow Well Purging Adjustable-rate peristaltic, bladder and electric submersible pumps are preferred for use during low -flow purging and sampling activities. Since purging and sampling are joined together as one continuous operation, care will be given to pump selection as it applies to the specific well conditions and analytes to be tested. Note that a ball valve (or similar valve constructed of polyethylene) may need to be installed to reduce the flow rate to the required level. The low -flow purging and sampling guidance is provided below: 1) Using the specific details of well construction and current water -level measurement, determine the pump intake set depth (typically the approximate mid -point of the saturated well screen or other target sample collection depth adjacent to specific high -yield zones). 2) Attach tubing and supporting rope (if applicable) to the pump and very slowly lower the unit until the pump intake depth is reached. Measure the length of supporting rope required, taking into account the pump length, to attain the required depth. Record the depth to the pump intake in the field logbook. Notes: 1 ) Sampling shall use new certified -clean disposable tubing. 2) Rope shall be clean, unused, dedicated nylon rope. If a pump is to remain in a well as part of a separate monitoring program, then the rope shall be suspended within the well above the water column for future use. If the pump is removed after sample collection, the rope shall be disposed. 3) After allowing time for the water level to equilibrate, slowly lower the electronic water -level probe into the well until the probe contacts the groundwater. Record the water level in the field logbook. M Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES ;,f,,DUKE V I ENERGY. 4) If the well has been previously sampled using low -flow purging and sampling methods, begin purging at the rate known to induce minimal drawdown. Frequently check the drawdown rate to verify that minimum drawdown is being maintained. If results from the previous sampling event are not known, begin purging the well at the minimum pumping rate of approximately 100 milliliters per minute (mL/min) (EPA, July 1996). Slowly increase the pumping rate to a level that does not cause the well to drawdown more than about 0.3 feet, if possible. Never increase the pumping rate to a level in excess of 500 mL/min (approximately 0.13 gallon per minute [gpm]). Record the stabilized flow rate, drawdown, and time on the field data sheets. 5) If the drawdown does not stabilize at 100 mL/min (0.026 gpm), continue pumping. However, in general, do not draw down the water level more than approximately 25% of the distance between the static water level and pump intake depth (American Society for Testing and Materials [ASTM], 2011). If the recharge rate of the well is lower than the minimum pumping rate but the drawdown is less than 25% of the distance between the static water level and pump intake depth after three volumes of well water are removed, then collect samples at this point even though indicator field parameters have not stabilized (EPA, July 1996). Commence sampling as soon as the water level has recovered sufficiently to collect the required sample volumes. Otherwise, the Volume -Averaging Well Purging method should be considered.Allow the pump to remain undisturbed in the well during this recovery period to minimize the turbidity of the water samples. Fully document the pump settings, pumping rate, drawdown, and field parameter readings on the Well Sampling / MicroPurge (Low Flow) Log in the field logbook. Note: For wells that either have very slow recharge rates, that draw down excessively (more than 25% of the distance between the static water level and pump intake depth) at the minimum pumping rate (100 mL/min or 0.026 gpm), or require a higher pumping rate (greater than 500 mL/min or 0.13 gpm) to maintain purging, the procedures described above may not apply. For these "special case" wells, the Field Team Leader shall seek guidance from the Project Manager about the appropriate purging and sampling methodologies to be employed (such as volume -averaged purging and sampling described in Section 3.3.2). 6) Once an acceptable flow rate has been established, begin monitoring designated indicator field parameters. Indicator parameters are pH, specific conductance, dissolved oxygen (DO), and turbidity. Although not considered purge stabilization parameters, temperature and oxidation reduction potential (ORP) will be recorded during purging. Base the frequency of the measurements on the time required to completely evacuate one volume of the flow through the cell to ensure that independent measurements are made. For example, a 500 -mL cell in a system pumped at a rate of 100 mL/min is evacuated in five minutes; accordingly, measurements are made and recorded on the field data form (Appendix C) approximately five minutes apart. Indicator parameters have stabilized when three consecutive readings, taken at three to five-minute intervals, meet the following criteria (EPA, March 2013): 5 • pH • Specific Conductance • DO • Turbidity Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES ± 0.1 standard unit ± 5% in pS/cm ± 0.2 mg/L or 10% saturation less than 10 NTUs The target for monitoring turbidity is readings less than ten nephelometric turbidity units (NTUs). In some instances, turbidity levels may exceed the desired turbidity level due to natural aquifer conditions (EPA, April 1996). When these conditions are encountered, the following guidelines shall be considered. • If turbidity readings are slightly above 10 NTU, but trending downward, purging and monitoring shall continue. -j'&' DUKE V I ENERGY. • If turbidity readings are greater than 10 NTU and have stabilized to within 10% during three successive readings, attempt to contact the Project Manager prior to collecting the groundwater sample. • If turbidity readings are greater than 10 NTU and are not stable, well sampling shall be based upon stabilization of more critical indicator parameters (such as dissolved oxygen) without attainment of the targeted turbidity. Attempt to contact the Project Manger if this condition is encountered prior to collecting the groundwater sample. • If after 5 well volumes or two hours of purging (whichever is achieved first), critical indicator field parameters have not stabilized, discontinue purging and collect samples. Fully document efforts used to stabilize the parameters (such as modified pumping rates). Note: While every effort should be taken to ensure that indicator parameters stabilize, some indicator parameters are more critical with respect to certain contaminant types. It is important to identify which indicator parameters are most important to the project prior to commencement of field activities so that unnecessarily protracted purge times can be avoided. For example, the critical indicator parameter associated with metals is turbidity. While it is desirable to sample wells when turbidity measurements are less than 5 NTU, Duke Energy recognizes that these values may not be attainable. Duke Energy, and its sub - consultants, have taken multiple steps (e.g., use of pre -packed screens, carefully selected sand pack, etc.) to alleviate the potential for elevated turbidity in newly installed wells. However, even with these conservative and targeted well installation specifications, other naturally occurring conditions (e.g., iron fluctuation) may prevent sampling of wells at turbidity values less than 5 NTU. Following sample collection and laboratory data evaluation, Duke Energy may review these data with respect to turbidity values to determine if additional well development is needed or if well construction has affected groundwater conditions. It may be necessary to redevelop wells from time to time to minimize It, Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES &,DUKE '*' ENERGY. sample turbidity. Fine silt and clay can collect at the base of a well over time. The effect on future sampling events can be reduced by lowering the tubing or pump to the bottom of the well (after all the groundwater samples have been collected) and pumping until the purge water from the bottom of the well screen is clear. Note: If purging of a well does not result in turbidity measurements of 10 NTU or less, the field sampler shall alert the Project Manager. The sampling team will assess options to reduce the turbidity as soon as possible. There are a variety of water -quality meters available that measure the water quality parameters identified above. A multi -parameter meter capable of measuring each of the water quality parameters referenced previously (except for turbidity) in one flow-through cell is required. Turbidity shall be measured using a separate turbidity meter or prior to flow into the flow through cell using an inline T -valve, if using one multi -meter during purging. The water quality meter (and turbidity meter) shall be calibrated as per manufacturer's instructions. Calibration procedures shall be documented in the project field logbook including calibration solutions used, expiration date(s), lot numbers, and calibration results. VA Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES &,DUKE 't' ENERGY. 3.3.2 Volume -Averaging Well Purging For wells that either have very slow recharge rates, that draw down excessively at the minimum pumping rate (100 mL/min or 0.026 gpm), or require a higher pumping rate (greater than 500 mL/min or 0.13 gpm) to maintain purging (i.e., low -flow well purging and sampling is not appropriate), the volume -averaging well purging and sampling method may be used. The Field Team Leader shall seek approval from the Project Manager before utilizing the volume -averaging method instead of the low -flow method. 3.3.2.1 CALCULATE PURGE VOLUMES Based on the depth -to -water (DTW) and total depth (TD) measurements, the volume of standing water in the well must be calculated using the following procedures. 1) Subtract DTW from TD to calculate the length of the standing water column (Lwc) in the well. TD — DTW = LWC 2) Multiply the length of the standing water column by the volume calculation (gallon per linear foot of depth) based on the inner casing diameter (see example list below) to determine the total standing water volume; this represents one well volume. VW = Lw, x 27Cr2 1 -inch well = 0.041 gallon per linear foot 2 -inch well = 0.163 gallon per linear foot 4 -inch well= 0.653 gallon per linear foot 6 -inch well = 1.469 gallons per linear foot 8 -inch well = 2.611 gallons per linear foot 3) Multiply the well volume calculated in the previous step by three and five to obtain the approximate respective total purge volume (the target purge volume is between three and five standing well volumes). For wells with multiple casing diameters (such as open bedrock holes), calculate the volume for each segment. Take the sum of the values and multiply by three and five to determine the minimum and maximum purge volumes, respectively. 4) Fully document the volume calculation in the field logbook or on the Groundwater Sampling Field Sheets. E: Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES ;,f,aDUKE V ENERGY. 3.3.2.2 PURGE THE MONITORING WELL Determine the appropriate pump to be used for purging—the preferred and most commonly used methods involve the use of a surface centrifugal or peristaltic pump whenever the head difference between the sampling location and the water level is less than the limit of suction and the volume to be removed is reasonably small. Where the water level is below the limit of suction or there is a large volume of water to be purged, use the variable speed electric submersible pump as the pump of choice (EPA, 2013). In some cases (shallow wells with small purge volumes), purging with a bladder pump may be appropriate. Once the proper pump has been selected: 1) Set the pump immediately above the top of the well screen or approximately three to five feet below the top of the water table (EPA, 2013). 2) Lower the pump if the water level drops during purging. Note: Use new certified -clean disposable tubing for purging and sampling. Note: Although volume -averaged sampling involves purging a specified volume of water (such as three to five well volumes) rather than basing purge completion on the stabilization of water quality indicator parameters, measuring and recording water -quality indicator parameters during purging provides information that can be used for assessment and remedial decision-making purposes. Indicator parameters are pH, specific conductance, DO, and turbidity as described in Section 3.3.1. Temperature and ORP will also be recorded during purging. 3) During well purging, monitor the discharge rate using a graduated cylinder or other measuring device, water -quality indicator parameters (if desired), and DTW as follows: • Initially, within approximately three minutes of startup, • Approximately after each well volume is purged, and then • Before purge completion. 4) Record pump discharge rates (mL/ min or gpm) and pump settings in the field logbook. Also, record any changes in the pump settings and the time at which the changes were made. 5) Maintain low pumping rates to avoid overpumping or pumping the well to dryness, if possible. If necessary, adjust pumping rates, pump set depth, or extend pumping times to remove the desired volume of water. 6) Upon reaching the desired purge water volume, turn off the purge pump. Do not allow the water contained in the pump tubing to drain back into the well when the pump is turned off. Use an inline check valve or similar device, or if using a peristaltic pump, remove the tubing from the well prior to turning off the pump. It is tr Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES &,DUKE '*' ENERGY. preferred to collect samples within two hours of purging, but acceptable for collection up to 24 hours of purging. Do not collect samples after 24 hours of purging. Note: The removal of three to five well volumes may not be practical in wells with slow recovery rates. If a well is pumped to near dryness at a rate less than 1.9 L/min (0.5 gpm), the well shall be allowed to completely recover prior to sampling. If necessary, the two-hour limit may be exceeded to allow for sufficient recovery, but samples should be collected within 24 hours of purge completion. 3.4 Sampling 3.4.1 Low -Flow Sampling Following are the procedures for the collection of low -flow groundwater samples. These procedures apply to sample collection for unfiltered and filtered samples using a 0.45 micron filter. See Appendix A for use of 0.1 micron filtered samples. 1) Record the final pump settings in the field logbook prior to sample collection. 2) Measure and record the indicator parameter readings prior to sample collection on both the stabilization form and in the field logbook. 3) Record comments pertinent to the appearance (color, floc, turbid) and obvious odors (such as sulfur odor or petroleum hydrocarbons odor) associated with the water. 4) Arrange and label necessary sample bottles and ensure that preservatives are added, as required. Include a unique sample number, time and date of sampling, the initials of the sampler, and the requested analysis on the label. Additionally, provide information pertinent to the preservation materials or chemicals used in the sample. 5) Collect samples directly from pump tubing prior to the flow-through cell or via the in-line T -valve used for turbidity measurements (as described Section 3.3.1 (6) above). Ensure that the sampling tubing remains filled during sampling and attempt to prevent water from descending back into the well. Minimize turbulence when filling sample containers, by allowing the liquid to run gently down the inside of the bottle. Fill the labeled sample bottles in the following order: • Metals and Radionuclides, • Filtered Metals and Radionuclides, if required, and then • Other water -quality parameters. 6) Seal each sample and place the sample on ice in a cooler to maintain sample temperature preservation requirements. 10 Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES ,&,DUKE '*' ENERGY. 7) Note the sample identification and sample collection time in field logbook and on Chain -of -Custody form. 8) Once sampling is complete, retrieve the sample pump and associated sampling equipment and decontaminate in accordance with procedures outlined in the Decontamination of Equipment SOP (Appendix A). 9) Close and secure the well. Clean up and remove debris left from the sampling event. Be sure that investigation -derived wastes are properly containerized and labeled, if applicable. 10)Review sampling records for completeness. Add additional notes as necessary. 3.4.2 Sampling after Volume -Averaging Purge The procedures described below are for the collection of groundwater samples after a volume -averaged purge has been conducted. Volume- averaging purge methods are described in Section 3.3.2. 1) If sampling with a pump, care shall be taken to minimize purge water descending back into the well through the pump tubing. Minimize turbulence when filling sample containers by allowing the liquid to run gently down the inside of the bottle. Fill the labeled sample bottles in the following order: • Metals and Radionuclides, • Filtered Metals and Radionuclides, if required, and then • Other water -quality parameters. 2) If sampling with a bailer, slowly lower a clean, disposable bailer through the fluid surface. Retrieve the bailer and fill the sample bottles as described above. Care shall be taken to minimize disturbing the sample during collection. 3.5 Sample Handling, Packing, and Shipping Samples shall be marked, labeled, packaged, and shipped in accordance with the sections outline below. 3.5.1 Handling The samples will be stored in coolers for transport to the site. Collected samples will be placed on ice in the sampling coolers for pickup or transport to the laboratory for analysis. 3.5.2 Sample Labels All sample containers will be new, laboratory cleaned and certified bottles. The bottles will be properly labeled for identification and will include the following information: • Project Site/ID 11 Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES &,DUKE '*' ENERGY. • Sample identifier (Well ID) • Name or initials of sampler(s) • Date and time of collection • Analysis parameter(s)/method • Preservative 3.5.3 Chain -of -Custody Record Sample transport and handling will be strictly controlled to prevent sample contamination. Chain -of -Custody control for all samples will consist of the following: • Sample containers will be securely placed in coolers (iced) and will remain under the supervision of project personnel until transfer of the samples to the laboratory for analysis has occurred. Upon delivery to the laboratory, the laboratory director or his designee will sign the Chain -of -Custody control forms and formally receive the samples. The laboratory will ensure that proper refrigeration of the samples is maintained. The Chain -of -Custody document contains information which may include: • Client name • Client project name • Client contact • Client address • Client phone/fax number • Sampler(s) name and signature • Signature of person involved in the chain of possession • Inclusive dates of possession • Sample identification • Sample number • Date & time of collection • Matrix • Type of container and preservative • Number of containers • Sample type - grab or composite • Analysis parameter(s)/ method • Internal temperature of shipping container upon opening in the laboratory 3.6 Field Quality Control Samples Field quality control involves the routine collection and analysis of QC blanks to verify that the sample collection and handling processes have not impaired the quality of the samples. 12 Duke Energy I Low Flow Groundwater Sampling Plan 3.0 PROCEDURES ;,f,,DUKE V I ENERGY • Equipment Blank — The equipment blank is a sample of deionized water, which is taken to the field and used as rinse water for sampling equipment. The equipment blank is prepared like the actual samples and returned to the laboratory for identical analysis. An equipment blank is used to determine if certain field sampling or cleaning procedures result in cross -contamination of site samples or if atmospheric contamination has occurred. One equipment blank sample will be prepared per day or per 20 groundwater samples, whichever is more frequent. Field and laboratory QA/QC also involves the routine collection and analysis of duplicate field samples. These samples are collected at a minimum rate of approximately one per 20 groundwater samples per sample event. A field duplicate is a replicate sample prepared at the sampling locations from equal portions of all sample aliquots combined to make the sample. Both the field duplicate and the sample are collected at the same time, in the same container type, preserved in the same way, and analyzed by the same laboratory as a measure of sampling and analytical precision. 3.7 Field Logbook Documentation Field logbooks shall be maintained by the Field Team Leader to record daily activities. The field logbook may include the following information for each well: • Well identification number • Well depth • Static water level depth • Presence of immiscible layers (yes — no) • Estimated well yield, if known • Purge volume and purge pumping rate • Time well purge began and ended • Well evacuation procedure and equipment • Field analysis data • Climatic conditions including air temperature • Field observations on sampling event • Well location • Name of collector(s) • Date and time of sample collection • Sampling procedure • Sampling equipment • Types of sample containers used and sample identification numbers • Preservative used 13 Duke Energy I Low Flow Groundwater Sampling Plan 4.0 REFERENCES ;��aDUKE I I ENERGY. The Field Team Leader shall review the field logbook entries for completeness and accuracy. The Field Team Leader is responsible for completion of the required data collection forms. Example field logs are in Appendix C. 3.8 Decontamination and Waste Management Sampling equipment decontamination shall be performed in a manner consistent with the Decontamination of Equipment SOP (Appendix A). Decontamination procedures shall be documented in the field logbook. Investigation -derived wastes produced during sampling or decontamination shall be managed in accordance with State and Station -specific rules for disposal of wastes. 4.0 REFERENCES American Society for Testing and Materials (ASTM). Standard Practice for Low -Flow Purging and Sampling for Wells and Devices Used for Ground -Water Quality Investigations, D 6771-02. 2011. Test Methods for Evaluating Solid Waste - Physical/Chemical Methods (SW -846), Third Edition. U.S. Environmental Protection Agency. Update I, II, IIA, IIB, III, IIIA, IVA and IVB. United States Environmental Protection Agency (EPA), Office of Research and Development, Office of Solid Waste and Emergency Response. Ground Water Issue, "Low -Flow (Minimal Drawdown Sampling Procedures). Document Number EPA/540/S- 95/504," April 1996. U.S. EPA. Region 4, Groundwater Sampling Operating Procedure. Document Number SESDPROC-301-R3, November 2013. U.S. EPA. Region I, Low Stress (Low Flow) Purging and Sampling Procedure for the Collection of Ground Water Samples from Monitoring Wells, Revision 2, July 1996. 14 Duke Energy I Low Flow Groundwater Sampling Plar Decontamination of Equipment SOP +,L)uKE '*' ENERGY._ go— e0r, hMMMMI&MM Decontamination of Equipment SOP 15 Duke Energy I Low Flow Groundwater Sampling Plar Purpose & Application ;,( DUKE V ENERGY. 1.0 Purpose & Application This procedure describes techniques meant to produce acceptable decontamination of equipment used in field investigation and sampling activities. Variations from this SOP should be approved by the Project Manager prior to implementation and a description of the variance documented in the field logbook. 2.0 Equipment & Materials • Decontamination water, • Alconox detergent or equivalent non -phosphate detergent • Test tube brush or equivalent • 5 -gallon bucket(s) • Aluminum foil • Pump 3.0 Procedure 3.1 Decontamination of Non -Disposable Sampling Equipment Decontamination of non -disposable sampling equipment used to collect samples for chemical analyses will be conducted prior to each sampling as described below. Larger items may be decontaminated at the decontamination pad. Smaller items may be decontaminated over 5 -gallon buckets. Wastewater will be disposed in accordance with applicable State and Station -specific requirements. 1. Alconox detergent or equivalent and water will be used to scrub the equipment. 2. Equipment will be first rinsed with water and then rinsed with distilled/deionized water. 3. Equipment will be air dried on plastic sheeting. 4. After drying, exposed ends of equipment will be wrapped or covered with aluminum foil for transport and handling. 3.2 Decontamination of Field Instrumentation Field instrumentation (such as interface probes, water quality meters, etc.) will be decontaminated between sample locations by rinsing with deionized or distilled water. If visible contamination still exists on the equipment after the rinse, an Alconox (or equivalent) detergent scrub will be added and the probe thoroughly rinsed again. Decontamination of probes and meters will take place in a 5 -gallon bucket. The decontamination water will be handled and disposed in accordance with applicable State and Station -specific requirements. W, Duke Energy I Low Flow Groundwater Sampling Plar 3.0 Procedure ;,f.�,DUKE V' ENERGY. 3.3 Decontamination of Groundwater Sampling Equipment Non -disposable groundwater sampling equipment, including the pump, support cable and electrical wires in contact with the sample will be thoroughly decontaminated as described below: 1. As a pre -rinse, the pump will be operated in a deep basin containing 8 to 10 gallons of water. Other equipment will be flushed with water. 2. The pump will be washed by operating it in a deep basin containing phosphate - free detergent solution, such as Alconox, and other equipment will be flushed with a fresh detergent solution. Detergent will be used sparingly, as needed. 3. Afterwards, the pump will be rinsed by operating it in a deep basin of water and other equipment will be flushed with water. 4. The pump will then be disassembled and washed in a deep basin containing non -phosphate detergent solution. All pump parts will be scrubbed with a test tube brush or equivalent. 5. Pump parts will be first rinsed with water and then rinsed with distilled/deionized water. 6. For a bladder pump, the disposable bladder will be replaced with a new one for each well and the pump reassembled. 7. The decontamination water will be disposed of properly. 3.4 Materials from Decontamination Activities All wastewater and PPE generated from decontamination activities will be handled and disposed in accordance with applicable State and Station -specific requirements. 17 Duke Energy I Low Flow Groundwater Sampling Plar Sampling Equipment Check List — Table 1 ,(�C)UKE 'e' ENERGY. Sampling Equipment Check List — Table 1 Duke Energy I Low Flow Groundwater Sampling Plar Sampling Equipment Check List —Table 1 DUKE '*1 ENERGY Table 1: Suggested Groundwater Sampling Equipment & Material Checklist Item Description Check Health & Safety Nitrile gloves Hard hat Steel -toed boots Hearing protection Field first-aid kit Fire Extinguisher Eyewash Safety glasses Respirator and cartridges (if necessary) SaranexTM/Tyvek® suits and booties (if necessary) Paperwork Health and Safety Plan Project work control documents Well construction data, location map, field data from previous sampling events Chain -of -custody forms and custody seals Field logbook Measuring Equipment Flow measurement supplies (for example, graduated cylinder and stop watch) Electronic water -level indicator capable of detecting non -aqueous phase liquid Sampling Equipment GPS device Monitoring well keys Tools for well access (for example, socket set, wrench, screw driver, T -wrench) Laboratory -supplied certified -clean bottles, preserved by laboratory (if necessary) Appropriate trip blanks and high-quality blank water Sample filtration device and filters Submersible pump, peristaltic pump, or other appropriate pump Appropriate sample and air line tubing (Silastic°, Teflon°, Tygon°, or equivalent) Stainless steel clamps to attach sample lines to pump Pump controller and power supply Oil -less air compressor, air line leads, and end fittings (if using bladder pump) In-line groundwater parameter monitoring device (for example, YSI-556 Multi - Parameter or Horiba U-52 water quality meter) Turbidity meter Bailer Calibration standards for monitoring devices 19 Duke Energy I Low Flow Groundwater Sampling Plar Field Logbook/Data Sheets +,DUKE '*' ENERGY._ Field Logbook/Data Sheets 20 Duke Energy I Low Flow Groundwater Sampling Plar Field Logbook/Data Sheets r+zDuKE *' ENERGY._ Groundwater Potentiometric Level Measurement Log ,fa DUKE �•/•.� DUKE ENERGY Well Number Time Depth to water (ft)* Depth to Bottom (ft)* Water Column Thickness ft Reference Point Elevation ft, Potentiometric Elevation (ft, IL MS Remarks Field Personnel: Checked By: * - Measurements are referenced from the top of the PVC inner casing (TOC) for each respective monitoring well. TOCs shall be surveyed by a Professional Land Surveyor and referenced to NAVD88. 21 Duke Energy I Low Flow Groundwater Sampling Plar Field Logbook/Data Sheets J� DUKE Ir" ENERGY: WellVSampling / MicroPurge Log DUKE ENERGY Project Name: Sheet: of Well Number: Date: Well Diameter: Top of Casing Elevation (ft, MSL): Pump Intake Depth (ft): Total Well Depth (ft): Recharge Rate (sec): Initial Depth to Water (ft): Discharge Rate (see): Water Column Thickness (ft): Controller Settings: Water Column Elevation (ft, MSL): Purging Time Initiated: 1 Well Volume (gal): Purging Time Completed: 3 Well Volumes (gal): ITotal Gallons Purged: WELL PURGING RECORD Volume Time Purged (gallons) Flow Rate (mL/min) Depth to Temperature Water (ft) (°C) pH Specific Dissolved ORP Turbidity (s.u.) Conductance Oxygen (mV) (NTU) Comments (ms/cm) (mg/L) Stabilization Min. I Well Criteria Volume +3°C + 10 15Nruor+10 +0.1 +3% +10% mV i if> s NTu GROUNDWATER SAMPLING RECORD Sample Number Collection Time Parameter Container Preservative. 22 Duke Energy I Low Flow Groundwater Sampling Plar Field Logbook/Data Sheets J� DUKE Ir" ENERGY: DAILY FIELD REPORT% DUKE ENERGY Project Name: Field Manager: Field Personnel: Date: Weather: Labor Hours Equipment Materials l,ieldObservations: Submitted by: lReviewed by: 23