Loading...
HomeMy WebLinkAbout_Cliffside Unit 5 CBE - Appendix E_20200107Duke Energy Coal Combustion Residuals Management Program December 18, 2019 Cliffside Steam Station— Inactive Unit 5 Ash Basin CAMA Closure Plan (Closure by Excavation) Revision 0 Wood E&IS Project No. 7812190194 APPENDIX E: EXCAVATION AND SAMPLING PLAN FOR CLOSURE BY EXCAVATION AREAS wood. EXCAVATION SOIL SAMPLING PLAN ROGERS ENERGY COMPLEX (CLIFFSIDE) FOR ASH BASIN EXCAVATION NORTH CAROLINA ASH BASIN CLOSURE DUKE ENERGY CAROLINAs, LLC. 526 SOUTH CHURCH STREET/ECI3K CHARLOTTE, NORTH CAROLINA 28202 � DUKE ENERGY Waste & Groundwater Programs Revision 2 December 2019 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) TABLE OF CONTENTS Revision 2 SECTION PAGE 1.0 PURPOSE..........................................................................................................................1 2.0 DOCUMENTATION SUMMARY...............................................................................1 TABLE 1 - Post Ash Basin Excavation Soil Data Collection......................................1 3.0 SOIL SAMPLING METHODOLOGY......................................................................... 2 3.1 Method Summary........................................................................................................ 2 3.1.1 Equipment...............................................................................................................2 3.1.2 Sample Locations................................................................................................... 3 3.1.3 Collection of Representative Samples................................................................. 3 3.1.4 Sample Preservation, Containers, Handling and Storage ................................ 4 3.1.5 Decontamination.................................................................................................... 4 4.0 VISUAL CONFIRMATION OF ASH REMOVAL .................................................... 5 4.1 Pre -Excavation Documentation................................................................................. 5 4.2 Ash Removal Verification Protocol........................................................................... 5 4.2.1 Field Documentation............................................................................................. 5 4.2.2 Fill Evaluation Criteria.......................................................................................... 6 4.3 Visual Removal Not Applicable................................................................................ 6 5.0 SOIL SAMPLING AND ANALYSIS........................................................................... 7 5.1 Soil Sampling................................................................................................................ 7 5.1.1 Scenario 1................................................................................................................ 7 5.1.2 Scenario 2................................................................................................................ 7 5.2 Fate and Transport Modeling..................................................................................... 8 TABLE 2 - Soil Parameters and Analytical Methods Totals and SPLP Analysis North Carolina Ash Basins to be Closed Via Excavation ........................................... 9 FIGURE 1 — Rogers Energy Complex (Cliffside) Sample Grid ................................ 10 Page i Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) 1.0 PURPOSE Revision 2 The purpose of this Excavation Soil Sampling Plan is to provide a standardized method for collecting soil samples at Duke Energy North Carolina ash basins where areas of excavation are included in the approved Closure Plan.. Soil samples described in this Excavation Soil Sampling Plan will be collected following visible ash removal from excavation areas identified in the approved Closure Plan. This Excavation Soil Sampling Plan is applicable to the collection of representative soil samples. Analysis of soil samples may be chemical or physical in nature and may be used to determine the following: • Extent and magnitude of constituent occurrence • Input concentrations for groundwater fate and transport model The methodologies discussed in this Excavation Soil Sampling Plan are applicable to the sampling of soil in ash basin excavation areas. For the purposes of this plan, soils are those mineral and organic materials remaining after all visible ash has been removed. 2.0 DOCUMENTATION SUMMARY TABLE 1 - Post Ash Basin Excavation Soil Data Collection Task Description Test Depth Visual Inspection on 100' X 100' grid Visually confirm primary source node removal at nodes (Figure 1) and N/A N/A document with photographs. Soil sample analysis on 100' X 100' Collect representative samples at 0 - 6 inches' grid node nodes (Figure 1) the appropriate PLM 2 2 5' depths. 0 - 6 inches' Soil Sample Analysis on an acre grid Collect representative samples at the Total Metals 2 2.5 7 7.5 systemz appropriate depths. SPLP 12' - 12.5' 17' - 17.5' Notes: 'If a certain six-inch sample interval does not yield sufficient soil volume to fill five 8-ounce sample bottles, the sample interval may be expanded to twelve inches to allow for sufficient soil sample volume. The revised sample interval should be appropriately documented. 2Excavation is complete once confirmed by visual inspection and PLM analysis per Section 4.0. Page 1 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) Revision 2 3.0 SOIL SAMPLING METHODOLOGY 3.1 Method Summary This Excavation Soil Sampling Plan has been adapted from Environmental Protection Agency (EPA) Standard Operating Procedures (SOPs) #2012 and #2006 and North Carolina Department of Environmental Quality (NC DEQ) Attachment 1 Coal Combustion Residuals Surface Impoundment Closure Guidelines for Protection of Groundwater, November 4, 2016. Soil samples are collected directly using stainless steel or plastic trowel, spade, shovel, or scoops. Following collection, soil is transferred from the sampling device to a stainless steel or plastic bowl to be homogenized. Once homogenized, the soil is 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 2. Ash presence is quantitatively determined by polarized light microscopy (PLM) by Duke Lab or state approved vendor. PLM analysis passes visible light through a pair of polarizing filters to create optical effects used in identifying unknown materials. This method is commonly used in asbestos and coal ash identification. 3.1.1 Equipment • Stainless steel or plastic trowel, scoop, spade or shovel — Used for collecting soil samples from surface locations. • Sample containers — To be supplied by Duke Energy Laboratory with appropriate cooler(s). Estimated that five 8-ounce sample bottles with Teflon -lined lids will be required for each sample location and sample depth. 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 during sampling. • 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. Page 2 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) Revision 2 • Stainless steel or plastic spoon — Used for homogenizing soil samples within a stainless steel or plastic bowl. • Stainless steel or plastic bowl — Used for homogenizing soil samples, when applicable. • Camera — Used for photo -documentation of sample locations and samples. • GPS — Device used to obtain elevation, latitude and longitude of sample location. • Trash bag — Used to dispose of gloves and any other non -hazardous waste generated during sampling. • Decontamination supplies and equipment. 3.1.2 Sample Locations General locations for soil sampling are determined by the soil scientist in the field at a rate of one soil sample for every 1 acre of ash basin area excavated. Actual sampling locations on site may vary to account for site conditions and to allow collection of representative samples. Representative samples reflect areas where all ash has been visually excavated and natural soil is observed. 3.1.3 Collection of Representative Samples For the purpose of this plan, surface soil is considered to range from 0 to 6 inches in depth, while deeper samples will be collected at a range of 2 to 2.5 feet below ground surface (bgs), 7 to 7.5 feet bgs, 12 to 12.5 feet bgs, and 17 to 17.5 feet bgs (Table 1) unless bedrock, refusal, or the water table are encountered. A surface soil sample and deeper samples will be collected at each location for every 1 acre of ash basin excavated. A new pair of nitrile gloves is worn at each sampling location and each depth. Each sampling location is recorded on the site map prior to collecting the sample, if location is not already noted on the map. The GPS location of each sampling location (i.e. elevation, latitude and longitude), sample descriptions, and area photographs are also recorded. All sampling equipment is decontaminated prior to use irrespective of depth. The following procedure will be used to collect representative soil samples with a scoop, shovel, trowel, geoprobe, or excavator: • Locate general sampling locations. • Determine suitability of sampling location for a representative sample. • If sampling location appears to reflect representative conditions that would allow collection of a representative sample, proceed with sampling procedure. If location is not indicative of conditions that would allow collection of a representative sample, notify the project manager so an alternate location can be identified. • Using a decontaminated sampling instrument, remove the desired thickness and volume of soil from the sampling area. The sampler must obtain enough soil to fill five 8-ounce sample bottles. If a certain six-inch sample interval does not Page 3 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) Revision 2 yield sufficient soil volume to fill five 8-ounce sample bottles, the sample interval may be expanded to allow for sufficient soil sample volume. The revised sample interval should be appropriately documented. • Transfer the sample into an appropriate sample or homogenization bowl. Non - dedicated containers should be adequately decontaminated. Stir for approximately one minute until there appears to be a uniform color and consistency. • Transfer homogenized sample to a labeled container(s) of appropriate size and construction for the analyses requested. • Secure sample container tightly. 3.1.4 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 2 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 2, 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 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. 3.1.5 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. Detergent wash and brush cleaning 2. Tap water rinse 3. De -ionized water rinse 4. Air dry 5. Wrap sampling tools with plastic Page 4 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) Revision 2 4.0 VISUAL CONFIRMATION OF ASH REMOVAL 4.1 Pre -Excavation Documentation Closure by excavation is defined herein as removing the primary source (primary source of potential constituents of interest) to the point that ash is not visible to the unaided eye at the ground surface. Closure by Excavation in this Excavation Soil Sampling Plan, can refer to areas of excavation occurring under any closure scenario, however Closure by Excavation might not apply to the full basin. Primary source ash is the main body of ash that was deposited in the basin. This method is intended solely to verify and document primary source ash removal, and is not intended to validate environmental quality standards of the subsurface (considered the secondary source of potential constituents of interest). Pre -excavation documentation would consist of: • Review topographic mapping, aerial photography, construction drawings, and boring logs to estimate the pre -ash placement topography and/or ash/soil interface • Preparation of an ash basin figure illustrating a grid spacing of 100 feet (Figure 1). Each grid point (node) will be assigned a unique identifier. Each node of the grid spacing (grid point) will represent a visual verification location. 4.2 Ash Removal Verification Protocol Ash excavation will be considered complete based on visual and PLM confirmation that all ash has been removed. Ash removal will be based on sampling of the ash/soil interface and analysis by PLM. Soil samples will be examined utilizing methods outlined in American Society for Testing and Materials (ASTM) D2488, Standard Practice for Description and Identification of Soils (Visual -Manual Procedure). Vertical and horizontal excavation of ash can terminate when the remaining material is documented using PLM to contain less than 50% ash. Project will excavate ash until a visible change in color or texture confirms removal of all ash. This location shall be referred to as the ash/soil interface. If visual evaluation is inconclusive, then request additional evaluation to confirm ash removal. 4.2.1 Field Documentation Evaluate the excavated surface elevation relative to the pre -ash placement topography. Periodically check bottom elevation to evaluate if fill is present above historic bottom elevation. Visual confirmation will be performed on a 100-foot grid system (Figure 1) unless conditions prevent such confirmation, as described in Section 4.3. Soil sampling will be performed on a 100-foot grid system and will be analyzed using PLM. • Personnel will locate each node by GPS or survey control, determine elevation, and evaluate whether that point is above or below the historic bottom elevation. Personnel will then observe the surface area represented by the node, to note if visible ash is present at the surface. If present, the location should be documented and excavation will need to continue. If the evaluation indicates the surface soils are residuum or bedrock, then hand auger to two feet below surface (or refusal) and perform visual -manual classification of the soils at the surface and depth according to Page 5 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) Revision 2 ASTM method D2488. Submit sample from surface and depth (or shallower if refusal) for PLM analysis. The conditions shall be documented by taking photographs. The classification indicator for fly ash will be grey to black silt -sized particles with no plasticity. The classification indicator for bottom ash will be grey to black sand to gravel sized particles and porous. If the node point elevation is near the historic bottom elevation then personnel can conclude the primary source is removed when the following criteria are met: 1. Residuum is indicated by observation 2. Soil is confirmed by visual manual classification (ASTM D2488) and PLM analysis less than 50% 4.2.2 Fill Evaluation Criteria The following procedure provides an approach that can be used to ascertain if the fill can remain in place. The procedure specified is based on the fill material and depth. If the elevation is less than eight feet above the historic bottom elevation of the ash basin and residuum is not observed, test pits may be excavated to historic bottom elevation or until residuum or bedrock is encountered, but no more than eight feet below the surface. o Personnel will evaluate existing information to determine if the test pits are necessary. If necessary, personnel may recommend excavating test pits at a frequency no tighter than 100 feet by 100 feet. o If visible ash is not discovered based on information defined above, the primary source removal may be confirmed. o If visible ash is discovered, continue excavation. • If the elevation is more than eight feet above historic bottom elevation of the ash basin and residuum is not observed, discuss with CCP Closure Personnel. o CCP Closure Personnel will confirm historic information and recommend a drilling and sampling program at a frequency no tighter than 100 feet by 100 feet to evaluate the presence of ash below the fill in accordance with the information defined above. If unusual features are revealed by the drilling, CCP Closure Engineering may request/recommend additional borings. Exploration is to be performed by continuous sampling during drilling. o If visible ash is not discovered based on information defined above, then the primary source removal may be confirmed. o If visible ash is discovered, continue excavation. 4.3 Visual Removal Not Applicable If possible, excavation of ash should continue even if groundwater is encountered. Visual documentation is challenging to complete when removal occurs in saturated conditions. Excavation of ash could be required in areas below the water table or ponded ash intended for removal by dredging. Page 6 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) Revision 2 A plan will be submitted to NC DEQ by Duke Energy pertaining to the removal of ash if these conditions or other restricting factors occur. 5.0 POST EXCAVATION SOIL SAMPLING AND ANALYSIS 5.1 Soil Sampling Analytical evaluation of s the remaining soils (less than 50% ash per PLM analysis) will be necessary to evaluate the extent of potential secondary source impacts depending on the depth of the water table and any proposed institutional or engineering controls that may be used in the area of excavation. Soil sampling will not be required if refusal or the top of bedrock are encountered, or the remaining soils are below the water table. Soil samples for laboratory analysis must be collected in a manner that will ensure a relatively uniform distribution of particles throughout the six inch sample. The systematic approach and design for soil sampling and analysis is dependent upon two scenarios: • Scenario 1: Remaining soil (containing less than 50% ash per PLM analysis) is located above the seasonal high water table and final constructed institutional and/or engineering controls will restrict infiltration from the surface reaching the water table (e.g. installation of a liner system). Scenario 2: Remaining soil (containing less than 50% ash per PLM analysis) is located above the seasonal high water table and infiltration from the surface would continue to reach the water table. 5.1.1 Scenario 1 Confirmation sampling will include discrete surface samples collected from the first six inches of the soil. Sampling will be performed on an acre grid system. This sample collection methodology shall be sufficient to characterize the horizontal extent of any remaining potential secondary source impacts for comparison with the NC DEQ Preliminary Soil Remediation Goals (PSRG). The samples shall be analyzed by a North Carolina certified laboratory for total concentrations for the parameters defined in Table 2. No SPLP testing is required. 5.1.2 Scenario 2 Confirmation sampling will include collection of both discrete surface and subsurface soil samples performed on an acre grid system. Discrete surface samples will be collected from the first six inches of the soil and a subsurface soil sample will be collected at 2 to 2.5 feet below ground surface (bgs), 7 to 7.5 feet bgs, 12 to 12.5 feet bgs, and 17 to 17.5 feet bgs unless refusal, bedrock or the water table are encountered. The use of a geoprobe or excavator is anticipated. This sample collection methodology shall be sufficient to characterize both the horizontal and vertical extent of any remaining potential secondary source impacts for comparison with the NC DEQ PSRGs and/or input into the soil leachate model. The samples shall be analyzed by a North Carolina certified laboratory for both total concentrations and SPLP for the parameter defined in Table 2. Page 7 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) Revision 2 5.2 Fate and Transport Modeling Contingency for stabilization of remaining amounts of potential secondary source impacts in a manner that will meet the intent of North Carolina Groundwater 2L Rules and closure requirements shall be considered as site conditions dictate. Provisions to develop groundwater flow and transport models to evaluate protection of groundwater criteria if potential secondary source material are left in place shall be considered. In addition, the possibility of metals leaching from a potential change in pH and geochemical conditions related to dewatering and excavation shall be considered along with plans for groundwater models to assess resulting site conditions. Page 8 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) Revision 2 TABLE 2 - Soil Parameters and Analytical Methods Totals and SPLP Analysis North Carolina Ash Basins to be Closed Via Excavation 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 6020B Barium mg/kg or µg/I EPA 6010D Beryllium mg/kg or µg/I EPA 6020B 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 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 µg/I EPA Method 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 6020E 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) if Scenario 2 is applicable. Page 9 Excavation Soil Sampling Plan December 2019 Rogers Energy Complex (Cliffside) FIGURE 1— Rogers Energy Complex Sample Grid Revision 2 Page 10 FIGURE 1 REV .____ F ljIII III IIII IIII / l/IIIII II 111 lfft�ll � I �l 11 / I II JI I Jill I((`�� /r\ IQ, 111�\1\\1�1111�II11IIII II IIII lllllJill l �Illlllllllllllllllllllll�11111111�1 IIIIIIIIJIlIII Ill/ Il �3040 � /\Ill\� Il IIII lll(� Illll \\�\\\\�\\ I l 111 /J I III l till (III 1 II I I II ° 1111�\\\\�1111 III )UI 1\\\ \III I(fl a°o I0,,��11,111 7s0_\�%y��wv\� %J�1111 IIIIIIII Illh'1111AA\\\ \�VA�II�IIII�IIII�IIII \ / l,�/ /�_ �vv� ,,vy �yI/IIIII) IIIII IIIIIll IIIII / II 111 II III IIII IIII II ll l /i/ /% , yv` = '<s l//y �/ ll I II III IIII�IIII�IIIIIII IIIII/ll/I/l/// v \ \ I I I l \ v I111�\\� ��\l\I�I(IJlllll�VAvVv\\\\\\\\IIIIVII\VA\vvv ����, — / �IJJI II C3, I of/Imo 1 /IIII I \ I �IIIIIIIIIIIIII IIII Ill / I l l I � l l I�) / \II ,^ I I do ///�%,'/ �'///� ='/'�/%lllrll'iI1�� 1I °IIII ° I ' I I I 11 atiF V � \ V I Ill // / I�� IIIII 1V A A� I 1 )( l 111 l/ l l l l 1 I \\II�IIl1�1I1�//�/////�/ Ill/ \ > — �I�II 1C vpN 0_r All, fAl // X C� I I \\\\\ \\\\ I — II/ / / / �i // >0�0 \0 IIIIII/IIIl I/III�I IIIl I�I /I�III' IIIlI/�IIIl(IIII/IIII�I/I/lIII�lII/jlII/I/IIIl/II/II//Il/I/lI/I/IIl// llll/J/�lll�1l/l1� llAl/1l/\I/\�l1l1 uI1l/\AI 1l�\l�1llllV\I lAI�lI1vI\ ��I\ I�\\11'\l\ll \/\l v\\l V-11l \ \I�l�°v 1 I1 IIIvI1II II�I IljI I� IIIlII IIllIlI vl1lIIl1l1I I/III 1//II�I/III°I I1• \ I .V �1i1 \ -oo_com�2e0s 0 y/ v0 20\0 \ \v \ 400 FT/lls° v Jill / / lI1I IIIIu llIl770IIIIlIIIIII1 ¢ \v v A— C) 7 VIllIIIIIlI � lI /ti0IIIlA'IItlII llIII \ ��i/ / \��a 1 �a — I 1� IIIIIIIIIII II I I IIIII�� / ° I IIII I) I IIII II Q\\\ �� AlIllll\ \ 1 1 v rT///// // // /II� ° it/i I Il JJ I 1 �I I Illlll�llll �11 70o s0 ^ 1 1� A / / \\ 111 III \ \ V v / I I �1 / / / / / / /l / ll Ill/ II l 7101 / 1 / /i � 73U %i� 1 III III 11/l//���— llllll I�I 11)111 74 A IIII I\\1 IIII l�i — A \ g I / l // IIIIIIIIIIIIIIIIIIIIIIlll111113I1/ 780 — �IIIIIIIII C �Il 1 IIIIII \ �a — ll� ��_---_--- Il/ /—v— 1 AC NO\ X7/ vA\ \� / — (�1/1 />78n ) �-- oo� A Ill///i =� �• /"= _= y_—_ _ � \\ — \ I �\ v\\\V � / / 1 f 001\,� � � / j / /j \ / //— � „ \ V _ � — vA /� j / A / � � � � / Ate/ / � \� �— — %(�k 7so — \ TITLE - ,76o > III I CLOSURE BY EXCAVATION -CLOSURE PLAN //— 1 wood.ROGERS ENERGY COMPLEX - CLIFFSIDE STEAM STATION ����\\��A\\w�\\�V�\A\�\\�\�\ \� ��II I \�\\�AV�\yA\v\\\�vv�\��� / \�A\ / � AVA�// 1 // �/II I /I I/1 11 / I ll 1 �\��/v/�vv ���vv � —�--- � / �+I � / �\ VAS\\1V�A1111\\ A I 11A11� \\ \ ywvvv vvv�A\v y�v��w��w������� � __ y/ �—; �% —/ ;yam/_ ���/ �y���� /✓r//// //r ////ll �'e/(l / /% �_ =--7 0 —__ — /// IIII II I\11IA1 1V A l \ II II 1I1 I l I I I I lIII1I1I ll1 l// 1 l / IlJ 1 I 11 F \\ L\LWood Environment & ACTIVE ASH BASIN EXCAVATION GRID Infrastructure Solutions Inc. \\\ _\\\\ = I , I I / / 2801 YORKMONT ROAD, SUITE 100 II\\ � Illy 1 s 1\\\ \������ � /� /� // \ 1 \ I I I I I / �\ \ ( / /// / 1 I I I 11 /ll )\\ \ \\ CHARLOTTE, INC 28208 FOR TEL: (704) 357-8600 FAX: (704) 357-8638 ENSURE: INC ENG: F-1253 INC GEOLOGY: C-247 ISSUED FOR PERMITTING - NOT RELEASED FOR CONSTRUCTION � � \ � ��//ii� / / v 4 — SEAL SCALE AS SHOWN DES' VMO NOTE:/// / x 1 I / 1. THE "APPROXIMATE LIMITS OF ASH BASIN FACILITY BOUNDARY" AND THE "APPROXIMATE LIMITS OF CCR BOUNDARY ARE BASED ON AERIAL PHOTOGRAPHY, // /� \ r\ J DUKE DWG TYPE: DWG DFTR : VMO/ANE TOPOGRAPHIC MAPPING, AND OTHER HISTORICAL DRAWINGS AND INFORMATION AND SHOULD BE CONSIDERED APPROXIMATE. THE "APPROXIMATE LIMITS OF /%�/ x \ / RGYJOB NO: 7812-19-0194 CHKD: KRD ASH BASIN FACILITY BOUNDARY' INCLUDES THE CONTAINMENT DAMS AND DIKES WHILE THE "APPROXIMATE LIMITS OF CCR BOUNDARY" EXCLUDES THOSE STRUCTURES AND IS BASED ON UPDATED TOPOGRAPHIC MAPPING, REPORTED OPERATIONAL LEVELS, AND SUBSURFACE DATA COLLECTED WITHIN THE BASIN. ENE® IT SHOULD BE NOTED THAT THE DETERMINATION OF THE ACTUAL LATERAL EXTENT OF THE CCR MATERIALS WILL TAKE PLACE PRIOR TO, AND/OR DURING, '1 \ \ I l / \ DATE: OCTOBER 15, 2019 ENGR: JB IMPLEMENTATION. NOT FOR 2. EXPLORATIONS PERFORMED IN ASH STORAGE AREA 2 INDICATED NO PRESENCE OF ASH, THEREFORE ASH STORAGE AREA 2 IS NOT INCLUDED IN THE ASH BASIN J �\ / \ I FILENAME: RemovalGrid ActiveBasin.dw APPD: JB , / / CONSTRUCTION CLOSURE PLAN. - g REFERENCES: \ — — ��� 1 ! I / DWG SIZE DRAWING NO. REVISION 1. ASH BASIN FACILITY BOUNDARIES, BORING LOCATIONS, PIEZOMETER LOCATIONS, AND WETLAND AND SEEP LOCATIONS PROVIDED BY DUKE ENERGY. —� 11` �// 2. EXISTING TOPOGRAPHIC INFORMATION WAS PRODUCED FROM PHOTOGRAMMETRIC METHODS FROM AERIAL PHOTOGRAPHY OBTAINED ON JULY 31, 2015 BY WSP. / _\�� 1111111�� \\ // 22 ANSI FIGURE 1 ---- REV DATE JOB NO. PROJECT TYPE DES DIFTR CHKD ENGR DESCRIPTION INCHES 1 2 3 TENTHS 10 20 30 4 I I I I 5 1 1 I I 8 1 1 0 I Plotted By: Bell, Josh Sheet Set: 7812190194 — Active Ash Basin Layout:.011 EXCAVATION PLAN December 18, 2019 03: 45: 02pm Q:\Duke\CliffSide\7812190194 — Cliffside Closure Plan \Exhibit\Rem oval Grid_ActiveBasin.dwg FIGURE 2 IREV -- — — — Il\\_\�I/—!'�/ �/a�///�I�/\ \ /\� �I1�iI l �'� /l�%j\ _/1\ //� i\ v 1/Il/ /�/i,\�/\/�\//l\l��1/\ — �////�/\l_/v/\—� \//� /—l//\��I\ / '/_//`�/Iv/lIV\\ \\�Il/ =v\ �a Il1ll I/i/lI 1��A\ l�l� �I l<�—I�/l//IvIIlvIl/III_il Il/ �III/ /'i�/ll\III II///IIl% v \II� / \"\/llIIIIIIIIII\ /I/� \ \\ I(vi II/IIlIIIIiI I�/ I/I\I II —II\ III�I\ v/l�Iv\�vA\ II—�III�\//I�Iir \ /%I//I`I�\\ rIII IlI// /I�I / �/IIIv AIIIl/�I \/I/ II ///I \///I/I/I I—\Il\ �\/II \ II\/�; i,/I/l'IIl\/I I%1AIII/�/lIv\IVIA\ 'Il//aIIiII I1/\/Il/ II/ \/ II �III��//II I\l�_iII/Ij� /II / Ii/\I %/II �I�IIII_ /I l_/ l� i\Il/ /tiIl �v// /IIo/I I'— \\vl/ :i�I//I////I///II�! I1/I�I 1 /I\i/\I/I/ � � C/,l/'��'/ /i//;//(\ /!/fII/-/-�l�\ —_/ jI i//l\///7/ l �\-� // !I\��J l//\/�//1//_l/ �✓/r/Il � f I \ V � I / v///\Hvl v \� I �! /\--�\-0—\/ -�--v\ \i/ � V\\— A/(— — \—�I\v\\ v\ \\ \/�\ /\v\ I )\v—\ \—/v \ —_ /v1\\A\\/\I\\v� I \\i\ \\—�\ V/_iiV \�\\ /—/ \/\o\—y\ /v\o\ V\r\\ /� \I\ �i�\\\ \1� _\_ (A__r\/\ \ \V/ w v/i \o_� \v- \' i/\—��/v_� V\�10 1\\v%i \\ � v/\vv � /� 1 /\— A� .✓ \A v\ /\v'�/ �/- \��V\/ I/�j / I/\"\\/ /+ I/ \V/\\�/ /IXr A/ / \II�/I//�,/�� \'� \//� �V 1/I\ /I/� I\ /A/\i/\/�\��+�/H/\Ii IIIIX// AV /\ /v/ / /v_ 1—v/ �- A�\_��= �/ 1vI — /I %I� M v\�� \ I—\\��—�( II\vv\w/ /y—1�1/ \\ � �� v �\\/��� \X1\1�// v � /\\ / � \ � \\ � \v/x�\\\/ ` / I /8 \) / ,� �\l /\v/ �/ /f os \\8\l/ov1v/v1v\/1/ /_ \\ 1 °\\1-\ , ///vv\vv_/ °v � / 1 > �\/v�vl11\ 1 / /\l � v/l\ ��� l�\/\ v/_\\/)\/, —1 \ �Iv�/l_\ /vv \�/ ��1/v��\%—\\l) i I 1\ \_ /\ _)/ \/� /\I i\ \ _ \ /\/ ,/ vv—' —� vo-/�\�_H\/vv � _—/_/_/ ��— \\,\ \Yi/\--/// AL_ \ /\ Hce ��_/I �v H1v/ /E �I� I \_�v_— \\/—\\_/ ,\vv/�\ _ /_v\� \ //Avv— v\/ =l\/I� \ _ ` / �/ \/ \vv�— _/1\\ \�\ \—\I1 /tev I —/ 1 \r1�JIIC I /�vI_\v1�/I\�V\ I /IJ\1I�Iv �I/v\�J IIII1IIII W/ / 3HE 750 ///3 1/ / /—� 1\_2� 0' \0 I \\\/ / �\/\\1V �-� //r2/Xy\0 \ \ 2o—// vx 4 0 / \/ F T 760 w /�//// > 11111111IIIII/ x II //// X "0'o 91 co// / / \\/I / v\�< � I//F F8/ 1�4IIIIIII 1 _U //� //714 7000/0YF UNT 5 NACTIv / 0 / \ / v 1/ / � / / ti / N_BB H BA 11/10I 16 WI 680 / 690 ok, / 71 A/ D je%z 160 Qo 1TI 770 / /17m:< 8p ' _Aso p \ TITLE CLOSURE BY EXCAVATION - CLOSURE PLAN v\\\wood. ROGERS ENERGY COMPLEX - CLIFFSIDE STEAM STATION F Wood Environment &/ UNIT 5 INACTIVE BASIN EXCAVATION GRID Infrastructure Solutions, Inc. 2801 YORKMONT ROAD, SUITE 100 TEL: (704) 357-8800 FAX: (704) 357-8638CHARLOTTE, NC 28208 FOR ISSUED FOR PERMITTING -NOT RELEASED FOR CONSTRUCTION -1253 7LICENSURE: NCENG:F/ /v/ // 8 SEAL SCALE: AS SHOWN DES: VMO DWG TYPE: DWG DFTR: VMO/ANEI DUKE 810 YJOB NO: 7812-19-0194 CHKD: KRDENEK O DATE: OCTOBER15,2019 ENGR: JBNOTFOR CONSTRUCTION FILENAME: RemovalGrid_Unit5.dwg APPD: JB REFERENCES: DWG SIZE DRAWING NO. REVISIONI/I 1. BOTTOM OF ASH CONTOURS TAKEN FROM AMEC FOSTER WHEELER, WASTE STRATEGY ANALYSIS, CLIFFSIDE STEAM STATION, APRIL 17, 2015. 2. BORING LOCATIONS, PIEZOMETER LOCATIONS, AND SEEP LOCATIONS PROVIDED BY DUKE ENERGY. CO / 3. EXISTING TOPOGRAPHIC INFORMATION WAS PRODUCED FROM PHOTOGRAMMETRIC METHODS FROM AERIAL PHOTOGRAPHY OBTAINED ON JULY 31, 2015 BY WSP. �\\ \ /ll I / I 77 � I / 22 ANSI D' FIGURE 2 ---- REV DATE JOB NO. PROJECT TYPE DES DFTR CHKD ENGR DESCRIPTION INCHES 1 2 3 TENTHS 10 20 30 4 5 6 7 8 9 10 I I I I I I I Plotted By: Bell, Josh Sheet Set: 7812190194 — Unit 5 Inactive Ash Basin Layout:.010 EXCAVATION PLAN November 06, 2019 09: 44: 18am Q:\Duke\CIiffSide\7812190194 — Cliffside Closure Plan \Exhibit\RemovalGrid_Unit5.dwg