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Home My WebLink About6512_BasinDamSoilSamplingPlan_FID1339436_20190818�•� DUKE ENERGY, August 14, 2019 Ms. Elizabeth Werner NC DEQ Solid Waste Section 1646 Mail Service Center Raleigh, NC 27699-1646 RE: Ash Basin Dam Soil Sampling Work Plan - L.V. Sutton Energy Complex Dear Ms. Werner: 410 S. Wilmington Street Raleigh, NC 27601 Mailing Address Mail Code NC 15 Raleigh, NC 27601 919-546-7863 Duke Energy (Duke) submits the Ash Basin Dam Soil Sampling Work Plan for the L.V. Sutton Energy Complex. The majority of the soil comprising the former 1984 and 1971 ash basin dams will be regraded within the footprint of the former ash basins. However, there is excess soil and Duke proposes to use the soils from a portion of the dams as fill in the existing transmission corridor located onsite between the former basin and existing landfill. Per prior discussions via telephone, Duke proposes to collect 10 composite soil samples from 10 different dam cross -sections for analysis. If you have any questions or need any clarification regarding the information provided, feel free to contact me at john.toepfer@duke-energy.com or at 919-546-7863 at your convenience. Respectfully submitted, "pf Lead Engineer, Duke Energy EHS CCP Waste & Groundwater Programs cc: Dan Atkinson — Duke Energy Ricky Stroupe —Duke Energy Kent Tyndall —Duke Energy Mr. James McNash, P.E. — Geosyntec Consultants of North Carolina, P.C. Mr. Perry Waldrep— SynTerra Corp. Enc: Ash Basin Dam Soil Sampling Work Plan A►Sh Basin Dam SOIL SAMPLING WORK PLAN L.V. Sutton Energy Complex Duke Energy Progress, LLC. 526 SOUTH CHURCH STREET CHARLOTTE, NORTH CAROLINA 28202 � DUKE ENERGY: Waste & Groundwater Programs August, 2019 Ash Basin Dam Soil Sampling Plan August, 2019 L.V. Sutton Energy Complex TABLE OF CONTENTS SECTION PAGE 1.0 PURPOSE..........................................................................................................................1 2.0 SOIL SAMPLING METHODOLOGY.........................................................................1 2.1 Method Summary........................................................................................................1 2.1.1 Collection of Representative Samples................................................................. 2 2.1.2 Sample Preservation, Containers, Handling and Storage ................................ 2 2.1.3 Decontamination.........................................................................................................3 3.0 SOIL SAMPLING AND ANALYSIS........................................................................... 3 3.1 Soil Sampling................................................................................................................ 3 3.2 Sample Analysis........................................................................................................... 4 4.0 DOCUMENTATION...................................................................................................... 4 5.0 TABLES/FIGURES...........................................................................................................5 TABLE 1- SOIL PARAMETERS AND ANALYTICAL METHODS ......................... 5 FIGURE 1 - SOIL STOCKPILE SAMPLING MAP ...................................................... 6 i Ash Basin Dam Soil Sampling Plan August, 2019 L.V. Sutton Energy Complex 1.0 PURPOSE The purpose of this Soil Sampling Work Plan is to provide a method for collecting and analyzing soil samples from the 1984 and 1971 ash basin dams at the L.V. Sutton Energy Complex. All ash has been removed from the 1984 and 1971 ash basins and the dams are in process of decommissioning. The majority of the dams will be regraded within the footprint of the former ash basins. However, there is approximately 120,000 cubic yards of excess soils that will be used as fill within the existing transmission corridor located between the former ash basins and the existing landfill. As Duke Energy plans to utilize this excess soil onsite, sampling is necessary to ensure the soil will not present secondary source contamination. This Soil Sampling Work Plan is applicable to the collection of representative soil samples and analysis of soil samples will be used to determine the presence or absence of constituents. 2.0 SOIL SAMPLING METHODOLOGY 2.1 Method Summary This Soil Sampling Work Plan has been adapted from Environmental Protection Agency (EPA) Standard Operating Procedures (SOPS) #2012 and #2006. Soil samples are collected using a plastic trowel, spade, shovel, or scoops along with hand auger and drill rig for samples collected at depths below 6 inches. Following collection, soil is transferred from the sampling device to a plastic bowl to be homogenized. Once homogenized, the soils (composite) will be transferred into Duke Energy Laboratory supplied sample bottles. Soil samples will be submitted under chain of custody for the following analyses: total metals and Synthetic Precipitation Leaching Procedure(SPLP) metals. Analytical methods for total metals and SPLP metals are described in Table 1. Equipment • Sample bottles/containers — To be supplied by Duke Energy Laboratory with appropriate cooler(s). Estimated that up to five 8-ounce sample bottles with Teflon - lined lids will be required for each soil sample. For return of cooler to the lab, ice will be required. • Gloves — used for personal protection and to prevent cross -contamination of samples — nitrile, disposable, powderless. • Field clothing and Personal Protective Equipment— used as specified in the site Health and Safety Plan. • Sampling flags— used for identifying soil sampling locations. • Field notebook —a bound book used to record progress of sampling effort and record any problems and field observations duringsampling. Ash Basin Dam Soil Sampling Plan August, 2019 L.V. Sutton Energy Complex • Three-ring binder/book — used to store necessary forms and record and track samples collected at the site. • Permanent marking pen — used to label sample containers, document field logbooks, data sheets and chain of custody. • Plastic spoon — used for homogenizing soil samples within a plastic bowl. • Plastic bowl —used for homogenizing soil samples, when applicable. • Camera — used for photo -documentation of sample locations and samples. • Trash bag — used to dispose of gloves and any other non -hazardous waste generated during sampling. • Decontamination supplies and equipment. 2.1.1 Collection of Representative Samples All sampling equipment will be decontaminated prior to use. The following procedure will be used to collect each soil sample at each of the ten proposed cross -sections: • Locate general sampling locations and record coordinates with a GPS unit. Collect a soil column at each designated sampling location via drill rig, hand auger or plastic spoon/trowel or shovel. Combine samples from each cross- section location within a sample (Shown in Figure 1) mixing bowl and thoroughly mix. • Transferto the sample bottles and secure sample bottles tightly. 2.1.2 Sample Preservation, Containers, Handling and Storage Chemical preservation of soils is generally not recommended. Cooling to 4°C on wet ice is usually the best approach, supplemented by the appropriate holding time for the analyses requested. The Duke Energy Laboratory will supply the appropriate sample bottles for the collected soil samples. The sample volume is a function of the analytical requirements and the Duke Energy Laboratory will ensure the appropriate number of bottles are supplied. Ensure chain of custody is completed for sample bottle return to the Duke Energy Laboratory. Table 1 contains a list of parameters to be analyzed with corresponding reporting units and analytical methods. If a parameter or group of parameters is not included in Table 1, the laboratory performing the analysis should be contacted to determine the appropriate sample bottles, volumes, and preservatives. All non -dedicated sampling devices should be decontaminated and wrapped in plastic. The sampling device should remain in this wrapping until it is needed. Each sampling device should Ash Basin Dam Soil Sampling Plan August, 2019 L.V. Sutton Energy Complex be used for only one sample and then decontaminated or disposed of. Non -dedicated sampling devices should be cleaned in the field using the decontamination procedure described below. 2.1.3 Decontamination Decontamination procedures can be time consuming; having a sufficient quantity of sampling tools available is recommended. All non -dedicated sampling equipment must be decontaminated prior to reuse. Equipment decontamination consists of: 1. Detergentwash and brush cleaning 2. Tap water rinse 3. De -ionized water rinse 4. Air dry 5. Wrap sampling tools with plastic 3.0 SOIL SAMPLING AND ANALYSIS 3.1 Soil Sampling Sample locations will be collected in a manner similar to UST Guidelines for Sampling. At each of the ten cross -sections, samples will be collected from the mid -point of the upstream face of dam, the center top of dam and the mid -point of the downstream face of the dam. The 1984 ash basin dam is approximately 16 feet in height. The 1971 ash basin dam is not nearly as tall. The below listed sampling depths are based upon the 1984 ash basin. Depths from the 1971 ash basin dam will be determined in the field but will still consist of collecting 3 different sampling depths at each of the 3 sampling locations per cross-section. Mid -point upstream face (8 feet above basin floor) 0-6 inches 4-4.5 feet 7-7.5 feet Center top of dam (16 feet above basin floor) 3-3.5 feet 6-6.5 feet 10-10.5 feet Mid -point downstream face (8 feet above basin floor) 0-6 inches 4-4.5 feet 7-7.5 feet 3 Ash Basin Dam Soil Sampling Plan L.V. Sutton Energy Complex August, 2019 Therefore, at each cross-section, nine individual samples will be collected and homogenized together and result in one composite soil sample for laboratory analysis. There will be 10 cross - sections total as shown in Figure 1. 3.2 Sample Analysis The ten composite samples will be sent to the Duke Energy Laboratory for analysis of total metals and SPLP metals. The lab will test for the inorganic compounds listed in Table 1. The results will be compared to site background levels, along with the current Protection of Groundwater Preliminary Soil Remediation Goals (PSRG) and the Industrial/Commercial PSRG set forth by NCDEQ. If the 10 sample results for total metals do not exceed the Protection of Groundwater PSRG and/or site background (which ever is greater), then NCDEQ Division of Waste Management, Solid Waste Section will be notified and the soil will be used as general fill onsite within the transmission corridor between the former ash basin and landfill. 4.0 DOCUMENTATION A comprehensive report will be submitted to NCDEQ Division of Waste Management, Solid Waste Section and include the associated lab reports. If an exceedance is found when data is compared to background and/or PSRG for Protection of Groundwater, then Duke Energy will discuss further action and/or additional sampling plans with NCDEQ. 4 Ash Basin Dam Soil Sampling Plan L.V. Sutton Energy Complex 5.0 TABLES/FIGURES TABLE 1- SOIL PARAMETERS AND ANALYTICAL METHODS August, 2019 INORGANIC COMPOUNDS UNITS METHOD' Aluminum mg/kg or µg/I EPA 6010D Antimony mg/kg or µg/I EPA 6020B Arsenic mg/kg or µg/I EPA 6020E Barium mg/kg or µg/I EPA 6010D Beryllium mg/kg or µg/I EPA 6020E Boron mg/kg or µg/I EPA 6010D Cadmium mg/kg or µg/I EPA 6020B Calcium mg/kg or µg/I EPA 6010D Chloride mg/kg or µg/I EPA 9056A Chromium (Total) mg/kg or µg/I EPA 6010D Cobalt mg/kg or µg/I EPA 6020B Copper mg/kg or µg/I EPA 6010D Hexavalent Chromium mg/kg or µg/I EPA Method 7199/218.7 Iron mg/kg or µg/I EPA 6010D Lead mg/kg or µg/I EPA 6020B Magnesium mg/kg or µg/I EPA 6010D Manganese mg/kg or µg/I EPA 6010D Mercury mg/kg or µ EPA Methodg/I 7470A/7471B Molybdenum mg/kg or µg/I EPA 6010D Nickel mg/kg or µg/I EPA 6010D Nitrate as Nitrogen mg/kg or µg/I EPA 9056A pH SU EPA 9045D Potassium mg/kg or µg/I EPA 6010D Selenium mg/kg or µg/I EPA 6020E Silver mg/kg or µg/I EPA 6020E Sodium mg/kg or µg/I EPA 6010D Strontium mg/kg or µg/I EPA 6010D Sulfate mg/kg or µg/I EPA 9056A Thallium (low level) (SPLP Extract only) mg/kg or µg/I EPA 6020B Vanadium mg/kg or µg/I EPA 6020E Zinc mg/kg or µg/I EPA 6010D Notes: 1. Soil samples to be analyzed for Total Inorganics using USEPA Methods 6010/6020 and pH using USEPA Method 9045, as noted above (or similar approved methods). Soil samples will also be analyzed for leaching potential using SPLP Extraction Method 1312 in conjunction with USEPA Methods 6010/6020 (or similar approved methods). Ash Basin Dam Soil Sampling Plan August, 2019 L.V. Sutton Energy Complex Is1411:10M111lIW11l014i"AaIM&_T►TiI14IMH►vil_j� d i ff $1 84 Basin LEGEND Dike CresF (-1600 LF� Notes 84 Dike 71 Basin Proposed Sample Bike Crest - Elevation 32' 12' Location Cross Toe of Dike - Elevation 14' 9' Section (Every -230') ILI