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HomeMy WebLinkAbout6512_Duke_Sutton_OpsPlan_DIN25548_20160922Prepared for Duke Energy Progress, LLC 526 South Church Street Charlotte, North Carolina 28202 OPERATIONS PLAN L.V. SUTTON ENERGY COMPLEX ONSITE COAL COMBUSTION RESIDUALS LANDFILL Wilmington, North Carolina Prepared by Geosyntec Consultants of NC, PC 1300 South Mint Street, Suite 410 Charlotte, North Carolina 28203 License No. C-3500 Project Number GC5770 December 2015 (Rev.1) ____________________________ Victor M. Damasceno, Ph.D., P.E. North Carolina Registration No. 042284 Date: _______________ ___________________________________________________________________________ ViViViViViViViViVViViViViViViViViVictttorooooooooooooooooo M. Damasce Carolina Registrati 8 December 2015 er 20155555 (R(R(R(R(Revevevev.1.111) ))) ____ P.E..... io 222222222284848484844 __________________________________ __________________________ ennnnno,o,o,o,o,o,o,,o,o,,,,,PPPPPPPPPPPPPPPPPPh.hhhh D.DDDD , P ioooooooooooooon nnnnnnn NoNoNoNoNoo. ...040404040422222 D bb 202020151515155 Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx i December 2015 (Rev.1) DESCRIPTION OF REVISIONS The following table provides a brief description of revisions to the Operations Plan. The Operations Plan was originally submitted to the North Carolina Department of Environment and Natural Resources (NCDENR) in August 2015 and modified as shown in the following table: Revision Date of Document Description of Revisions Initial Issue August 2015 Initial issuance of document. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx ii December 2015 (Rev.1) TABLE OF CONTENTS 1 GENERAL FACILITY OPERATIONS ........................................................................ 1 1.1 Overview .................................................................................................................... 1 1.2 Contact Information .................................................................................................... 1 1.3 Safety .......................................................................................................................... 2 1.4 Access and Security Requirements ............................................................................. 2 1.5 Operating Hours ......................................................................................................... 2 1.6 Signs ........................................................................................................................... 2 1.7 Training ...................................................................................................................... 2 1.8 Record Keeping .......................................................................................................... 3 1.9 Design Drawings ........................................................................................................ 3 2 OPERATIONS MANAGEMENT .................................................................................. 5 2.1 Waste Handling and Landfill Sequencing .................................................................. 5 2.1.1 Landfill Capacity .............................................................................................. 5 2.1.2 Waste Acceptance, Disposal, and Screening Requirements ............................ 6 2.1.3 Construction and Demolition (C&D) Waste and Land Clearing and Inert Debris (LCID) ............................................................................................................. 7 2.1.4 Vacuum Truck Waste ....................................................................................... 7 2.1.5 Dust, Litter, Odor, and Vector Control ............................................................ 8 2.1.6 Fire Control ...................................................................................................... 8 2.1.7 Landfill Sequencing ......................................................................................... 9 2.1.8 Waste Placement .............................................................................................. 9 2.1.9 Compaction Requirements and Testing ........................................................... 9 2.1.10 Cover Requirements ....................................................................................... 11 2.2 Leachate and Contact Water Management ............................................................... 12 2.2.1 Contact Water Source 1 ................................................................................. 12 2.2.2 Contact Water Source 2 ................................................................................. 12 2.2.3 Contact Water Source 3 ................................................................................. 12 2.3 Leachate Collection System (LCS) .......................................................................... 13 2.3.1 LCS Maintenance ........................................................................................... 14 2.3.2 LCS Record Keeping and Sampling .............................................................. 14 2.3.3 Leak Detection System (LDS) ....................................................................... 14 2.3.4 LDS Maintenance........................................................................................... 15 2.3.5 LDS Record Keeping and Monitoring ........................................................... 15 2.3.6 LDS Response Action Plan ............................................................................ 15 2.3.7 Contingency Plan ........................................................................................... 17 2.4 Stormwater Collection Conveyance ......................................................................... 18 Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx iii December 2015 (Rev.1) 2.4.1 Stormwater Discharge .................................................................................... 18 2.5 Surface Water Basin Maintenance Requirements .................................................... 19 2.6 Groundwater Monitoring Well Access Requirements .............................................. 19 2.7 Landfill Gas Management ........................................................................................ 19 3 EROSION AND SEDIMENTATION CONTROL ..................................................... 20 3.1 E&SC Measures Monitoring and Maintenance ........................................................ 20 3.2 Surface Erosion Monitoring ..................................................................................... 21 4 VEGETATION MANAGEMENT ............................................................................... 22 4.1 Temporary Seeding ................................................................................................... 22 4.2 Permanent Seeding ................................................................................................... 23 5 LANDFILL CLOSURE ................................................................................................. 24 6 REQUIRED REGULATORY SUBMITTALS ........................................................... 25 LIST OF TABLES Table 1. Design Drawings ....................................................................................................... 3 Table 2. Landfill Expansion Life Estimation .......................................................................... 6 LIST OF APPENDICES Attachment 1 Dust Control Plan Attachment 2 Closure/Post-Closure Plan Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 1 December 2015 (Rev.1) 1 GENERAL FACILITY OPERATIONS 1.1 Overview The purpose of this Operations Plan is to provide a plan for the safe and efficient operations of the L.V. Sutton Energy Complex (Sutton) Onsite Coal Combustion Residuals (CCR) Landfill. This Operations Plan presents the operational requirements for: (i) General Facility Operations; (ii) Operations Management; (iii) Erosion and Sedimentation Control; and (iv) Vegetation Management along with guidance for Landfill Closure and Required Regulatory Submittals. The Operations Plan also includes Tables for Design Drawings, Landfill Life Estimation, and Appendices for Dust Control Plan, Phasing Drawings, and Closure/Post-Closure Plan. The Operations Plan was prepared consistent with 15A NCAC 13B .0505 Operational Requirements for Sanitary Landfills rules. Sutton is located in an approximately 3,308-acre property in New Hanover County, near Wilmington, North Carolina and is situated between the Cape Fear River to the West and the Northeast Cape Fear River to the east and is located approximately 1.9 miles south of the New Hanover County Municipal Solid Waste (MSW) Landfill. The Sutton plant is owned by Duke Energy Progress, LLC (DEP) and formerly operated as a three-unit, 575-megawatt coal-fired plant from 1954 until retirement in November 2013. Upon retirement of the coal- fired units in November 2013, a new 625-megawatt gas-fired combined-cycle unit began operating. The coal-fired units of the Sutton Plant are currently undergoing decommissioning and demolition. The Sutton property is classified within the I-2 (heavy industrial) District by the Zoning Ordinance, as defined by the County of New Hanover. 1.2 Contact Information Correspondence and questions concerning the operation of the Sutton CCR Landfill should be directed to the appropriate entity as follows: Owner Duke Energy Progress, LLC — L.V. Sutton Energy Complex 801 Sutton Steam Plant Road, Wilmington, NC 28401 (910) 341-4754 Facility Contact: Station Sponsor for Landfill Operations or Environmental Professional State Regulatory Agency North Carolina Department of Environment and Natural Resources Division of Waste Management, Solid Waste Section Asheville Regional Office 2090 US Highway 70, Swannanoa, North Carolina 28778 (828) 296-4500 Permitting Engineer: Larry Frost Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 2 December 2015 (Rev.1) 1.3 Safety Landfill operations at the Sutton CCR Landfill were developed considering the health and safety of the facility’s operating staff. The operating staff is provided with site-specific safety training prior to landfill operations, and onsite activities are to be conducted according to the applicable sections of Duke’s Safe Work Practices. 1.4 Access and Security Requirements The Sutton CCR Landfill is located entirely within Duke property limits. Security for the site shall consist of fencing, gates, berms, wooded buffers, and security check stations. Unauthorized vehicle access to the site shall be prevented around the landfill property by security check stations, woods, fencing, gates, and stormwater conveyance features. The access road to the site is of all-weather construction and will be maintained in good condition. Potholes, ruts, and debris on the road(s) will receive immediate attention in order to avoid damage to vehicles. 1.5 Operating Hours The Sutton Onsite CCR Landfill shall be operated seven days a week, as needed. 1.6 Signs A sign providing the landfill permit number and a statement reading “NO HAZARDOUS OR LIQUID WASTE PERMITTED” shall be posted at the site entrance and shall be maintained in good condition. Edge-of-waste markers shall be installed to delineate the edge of waste. These markers shall be maintained in good condition and remain visible at all times. 1.7 Training Due to the diversity and nature of job tasks required at the Sutton CCR Landfill, personnel shall be adequately trained to handle facility operations and maintenance. The Station Sponsor for Landfill Operations shall have a general understanding of all the tasks required for site operations. Individuals performing the various tasks shall have adequate training for the site-specific tasks they are assigned. Duke shall provide a site- specific training program for facility personnel. Noteworthy operations and maintenance tasks to be addressed in training include: • Maintaining accurate records of waste loading (quantitative and qualitative); • Operating requirements for stormwater segregation from exposed waste areas; and • Operating and maintaining the leachate collection system (LCS). Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 3 December 2015 (Rev.1) All training will be documented and training records will be kept on-site. The Station Sponsor for Landfill Operations will conduct operator training courses in accordance with the permit requirements. 1.8 Record Keeping An operating record is to be maintained on-site, including but not limited to the following records: • Leachate Collection System (LCS) – Periodic Maintenance Documentation; • Leachate monitoring; • Stormwater Maintenance and Inspection Logs; • Erosion and Sedimentation Control Inspection Logs; • Periodic Landfill Inspection Reports; • Dust Control Plan Monitoring Worksheets (included in the Dust Control Plan); • Groundwater Monitoring (and Sampling) Documentation; and • Operations Plan. The above records are to be kept in the operating record for the active life of the Sutton CCR Landfill and the post-closure care period. Information contained in the operating record must be furnished upon request to the North Carolina Department of Environment and Natural Resources (NCDENR) Division of Waste Management, Solid Waste Section (Division) or be made available for inspection by the Division. Additional records kept on site should include: • Solid waste facility permits; • Record of the amount of solid waste received summarized on a monthly basis based on scale records; • Regulatory agency inspection reports; • Permit-to-Construct Application; • Employee training program and records; and • Landfill drawings and specifications. 1.9 Design Drawings A list of the landfill engineering and facility plan design drawings developed for the Sutton CCR Landfill is provided in Table 1. The design drawings provide the location of landfill features, landfill construction details, and technical design and construction notes. Table 1. Design Drawings Drawing No. Title Drawing 1 Title Sheet Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 4 December 2015 (Rev.1) Drawing 2 Topographic Map Drawing 3 Existing Conditions Plan Drawing 4 Site Characterization Plan Drawing 5 Site Development Plan Drawing 6 Top of Subgrade Grading Plan Drawing 7 Top of Liner Grading Plan Drawing 8 Top of Leachate Collection System Grading Plan Drawing 9 Final Cover System Grading Plan Drawing 10 Leachate Storage Plan Drawing 11 Phasing Plan 1 Drawing 12 Phasing Plan 2 Drawing 13 Phasing Plan 3 Drawing 14 Groundwater Monitoring Plan Drawing 15 Construction Sequencing Plan I Drawing 16 Construction Sequencing Plan II Drawing 17 Construction Sequencing Plan III Drawing 18 Surface Water Management Plan Drawing 19 North Storm Water Pond Plan and Details Drawing 20 South Storm Water Pond Plan and Details Drawing 21 Erosion and Sediment Control Phasing Plan 1 Drawing 22 Erosion and Sediment Control Phasing Plan 2 Drawing 23 Erosion and Sediment Control Phasing Plan 3 Drawing 24 Landfill Cross Sections Drawing 25 Perimeter Berm Cross Sections Drawing 26 Liner and Final Cover System Details I Drawing 27 Liner and Final Cover System Details II Drawing 28 Leachate Sump Plan Drawing 29 Secondary Sump Cross Sections Drawing 30 Primary Sump Cross Sections Drawing 31 Leachate Collection System Details I Drawing 32 Leachate Collection System Details II Drawing 33 Leachate Management System Schematic Design Drawing 34 Surface Water Management Details I Drawing 35 Surface Water Management Details II Drawing 36 Surface Water Management Details III Drawing 37 Erosion and Sediment Control Details I Drawing 38 Erosion and Sediment Control Details II Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 5 December 2015 (Rev.1) 2 OPERATIONS MANAGEMENT The primary objective of operations management at the Sutton Onsite CCR Landfill is to dispose of CCR in compliance with permit conditions while operating in a safe manner. Landfilling operations will begin in Phase 1 (Cells 3 – 8) followed by Phase 2 (Cells 1 and 2) and Phase 3 (Cells 9 – 11), after which Phases 1, 2, and 3 will be filled to final grade. During landfill operations the working face in the cell will be limited to as small an area as practical, at the owner’s discretion, with waste in other areas covered with appropriate material. Contact water from the active face will be directed to chimney drains interior to the landfill footprint. Additionally, the landfill has been designed to provide separation of contact water from non- contact water. Contact water is defined as water that contacts waste, including exposed waste within the landfill, operational haul roads surfaced with bottom ash generally located within the limit of waste, and perimeter access roads between the point of landfill egress and the CCR Basins. Contact water will be managed as leachate while non-contact water will be managed as stormwater. Contact water and non-contact water separation are further described in subsequent subsections of this plan. 2.1 Waste Handling and Landfill Sequencing 2.1.1 Landfill Capacity The Sutton Onsite CCR Landfill is designed to receive waste at an annual disposal rate of approximately 1,040,000 cubic yards (cy) per year (or 1,250,000 tons per year) for the first 4 years of operation (once approximately 5,000,000 tons of CCR have been disposed), decreasing to 420,000 cy per year (approximately 500,000 tons per year) thereafter. The resulting landfill life for Phases 1, 2, and 3 is estimated to be approximately 12 years as represented in Table 2 below. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 6 December 2015 (Rev.1) Table 2. Landfill Expansion Life Estimation Construction Sequence Approximate Waste Footprint (acres)1 Estimated Airspace Available for Waste Disposal (cy)2 Estimated Lifetime (years) Ph a s e 1 Cell 3 10.1 840,787 0.9 Cell 4 9.2 810,807 0.8 Cell 5 8.9 766,286 0.7 Cell 6 9 806,715 0.7 Cell 7 9 818,223 0.8 Cell 8 9.9 902,372 0.9 Ph a s e 2 Cell 1 7.1 457,857 1.2 Cell 2 7.9 549,967 1.3 Ph a s e 3 Cell 9 10 916,989 1.5 Cell 10 9.5 1,038,598 1.5 Cell 11 10.5 840,385 1.6 Totals 101.1 8,748,987 11.9 Notes: 1. Within the limit of waste of the respective phase and rounded to the nearest tenth of an acre. 2. Rounded to the nearest 1,000 cy. 2.1.2 Waste Acceptance, Disposal, and Screening Requirements The Sutton CCR Landfill is permitted to accept the following on-site waste types: • Coal combustion residuals (CCRs) (including fly and bottom ash, pyrites and coal mill rejects, and boiler slag); • Waste water treatment sludge (WWTS); • Petroleum Contaminated site soils; and • Plant decommissioning-related materials. The landfill owner or operator shall notify the Division within 24 hours of attempted disposal of any wastes the landfill is not permitted to receive. At a minimum, hazardous waste, yard trash, liquid wastes (except as noted in section 2.1.6), regulated medical waste, sharps not properly packaged, polychlorinated biphenyls (PCB) waste as defined in 40 Code of Federal Regulations (CFR) 761, and wastes banned from Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 7 December 2015 (Rev.1) disposal in North Carolina by General Statute 130A-309.10(f), must not be accepted at the landfill. Asbestos waste will not be disposed of in the landfill. The removal of waste from the landfill is prohibited without owner approval. Waste will be hauled and disposed of by dedicated and consistent operators from the waste source to the landfill. Access to the interim waste storage location(s) (e.g., fly ash stockpiles, etc.), haul routes, and landfill are restricted; therefore, no screening of waste is recommended. 2.1.3 Construction and Demolition (C&D) Waste and Land Clearing and Inert Debris (LCID) The Sutton CCR Landfill may receive construction and demolition waste, land clearing waste, inert debris, untreated wood, and yard trash (leaves, sticks) resulting from operations at Sutton. These materials shall not be placed within 25 ft of the exterior slopes. Waste will be placed on the smallest active face as practical and compacted with a dozer as densely as practical. Specific monitoring and in-place density testing of C&D waste and LCID is not required. Compacted C&D waste and LCID will be covered as described in Section 2.1.8.1. 2.1.3.1 Operation Cover – C&D Waste When the C&D waste disposal area exceeds one-half acre, and at least weekly, the compacted C&D waste will be covered with a minimum of 6 inches of earthen material (e.g., soils, CCR) 2.1.3.2 Operational Cover – Other Wastes For wastes other than asbestos waste and C&D waste, operational cover consisting of soil will be applied as needed for dust control and stormwater management. The operations cover may be applied at a thickness suited to its purpose. For example, the operational soil cover may be applied in thinner layers to provide dust control and it may be applied in thicker layers where protection from surface erosion is desired. Dust control measures shall be provided in accordance with the Dust Control Plan. 2.1.4 Vacuum Truck Waste Vacuum truck waste shall consist of permitted waste materials as described in Section 2.1. The consistency of the vacuum truck waste may vary from a relatively dry state to a relatively wet, fluid-like state. Vacuum truck waste material shall be moisture conditioned by initial decanting of excess moisture from the waste or by mixing the waste with fly ash, bottom ash, or gypsum materials depending on its consistency. The vacuum truck waste shall be placed and spread in maximum 6-inch lifts near the center of the operational area. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 8 December 2015 (Rev.1) The vacuum truck waste shall not be placed within 50 feet horizontally from exterior landfill slopes or within 50 feet of chimney drain structure locations. The vacuum truck waste material shall be thoroughly mixed with fly ash or bottom ash during waste placement using a dozer or other similar grading equipment to provide additional moisture conditioning prior to compaction. In-place density testing of the vacuum truck waste materials is not required. Vacuum truck waste shall only be placed within the landfill during landfill operating hours when landfill operator personnel are present. The vacuum contractor shall coordinate vacuum truck waste placement with landfill operator personnel. A Vacuum Truck Waste Disposal Log shall be used to document vacuum waste placement within the landfill. A Vacuum Truck Waste Disposal Log shall be used to verify the origin of vacuum truck waste and will include the date, time, weather conditions, estimated waste volume, visual waste screening and non-permitted waste removal, and Operator representative approval. The Vacuum Truck Waste Disposal Log may be modified as needed by the Owner or Operator to provide additional site specific operations information. The estimated volume of vacuum truck waste generated will be documented by the landfill operator along with monthly truck scale log records to estimate the cumulative vacuum truck waste transported and placed within the landfill. Dust control measures shall be provided for the vacuum truck waste in accordance with the Dust Control Plan. 2.1.5 Dust, Litter, Odor, and Vector Control Litter, odors, and vectors are not anticipated to be concerns at the Sutton CCR Landfill. The waste placed in the landfill does not attract vectors, and wind-blown material is not anticipated to be a problem. Odors are typically not a problem at CCR waste landfills. Dust control is addressed in the Dust Control Plan included as Attachment 1. Generally, dust control measures will be implemented when necessary, and will include at a minimum watering of dusty roads and exposed work areas. Other measures include physical measures such as fencing and/or berms, temporary covers like tarps, spraying dust suppressants, and modifying the active work area. Additionally, interim cover will be seeded within 7 days in accordance with Erosion and Sediment Control requirements. 2.1.6 Fire Control No open burning shall be permitted at the Sutton Onsite CCR Landfill. There are no explosive gas concerns with CCR, ash waste/sludge, or mill rejects; therefore, the threat of fire is considered to be minimal. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 9 December 2015 (Rev.1) Although it is unlikely, if a fire occurs at the landfill, the Station Control Room (phone number: 910-341-4754) shall be notified, and equipment and stockpiled soil shall be provided to control accidental fires. Sutton personnel will notify the local fire department which will be immediately dispatched to assist with fire control. Any fire that occurs at the landfill shall be reported to the Division within 24 hours and a written notification will be submitted within 15 days by the Station Sponsor for Landfill Operations. 2.1.7 Landfill Sequencing The Sutton Onsite CCR Landfill will be developed in phases, from Phase 1 through Phase 3. The three phases are subdivided into 11 cells which could be constructed sequentially (e.g., Cell 3 then Cell 4), in alternate order (e.g., Cell 3 then Cell 2 then Cell 4), or at the same time. 2.1.8 Waste Placement Waste generated at Sutton is transported from the CCR Basins and interim CCR stockpile areas to the landfill by using dump trucks and/or conveyor systems. C&D and LCID waste shall be stockpiled separate from CCR and will transported to the landfill using dump trucks. Upon reaching the active face of the landfill, the waste is dumped from the trucks which then exit the landfill returning to the interim waste storage areas. The interim waste storage areas, haul roads, and landfill are located within secured areas at Sutton. The landfill surface shall be graded to promote separation between surface water and contact water. The landfill surface shall be graded to promote contact water drainage to the contact water collection system (e.g., chimney drains). No waste shall be placed in standing water. 2.1.9 Compaction Requirements and Testing After the waste is placed on the active face, the waste will be placed in consecutive, approximate 1-foot thick lifts that do not exceed a 10-foot operational lift. Prior to compaction of an existing lift, the existing and new material should be adequately blended. In-Place Density and Moisture Content Testing In-place density and moisture content testing shall be performed at a minimum frequency of one test per 10,000 cubic yards (or one test per 270,000 square feet per 12-inch thick lift). Waste shall be compacted to a minimum 95 percent of its Standard Proctor (ASTM D 698) maximum dry density. Compacted moisture content shall be within 5 percent of the material’s optimum moisture content as determined by ASTM D 698. If field density tests indicate that the relative compaction or moisture content requirements are not met, the material shall be moisture conditioned and/or re-worked and re-tested until the compaction density and moisture requirements are met. The field density testing report should document any failing tests and re-work required to meet testing requirements. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 10 December 2015 (Rev.1) In-place density tests shall be performed using the Sand Cone Method (ASTM D 1556), Drive-Cylinder Method (ASTM D 2937), or Nuclear Method (ASTM D 6938). If the nuclear method is selected, a minimum of one comparison density test using the Sand Cone or Drive Cylinder method shall be performed for every five nuclear density tests, and correlations between the test methods shall be developed and reviewed by the Engineer. A sample of ash material shall be collected from each density test location and placed in a sealed container for subsequent field and laboratory moisture testing. A family of Proctor curves shall be developed for the on-site ash material as standard Proctor moisture-density tests are performed as a reference for the field density testing. A minimum of one (1) one-point field Proctor test shall be performed for each day of field density testing. Additional one-point field Proctors shall be performed if the material changes. A material change is defined when the maximum dry density of the referenced standard Proctor test varies by more than 2 pounds per cubic foot (pcf). If the estimated standard Proctor maximum dry density based on the results of one-point Proctor testing indicates that the maximum dry density varies by more than 5 pcf from the nearest representative standard Proctor moisture-density relationship, an additional bulk sample of ash material shall be obtained and standard Proctor testing shall be performed for the sample as a reference for the field density testing. Field moisture content testing shall be performed for each density test using the Direct Heating Method (ASTM D 4959). The Nuclear Method (ASTM D 6938) shall not be used for moisture content testing on the ash material. Comparison laboratory moisture content testing shall be performed using the Oven Method (ASTM D 2216), at an oven temperature of 60 degrees Celsius. The laboratory moisture content shall control in the event of a discrepancy between laboratory moisture content and in-place moisture content. Laboratory Testing Laboratory moisture content testing shall be performed in conjunction with the field density testing as described above. The laboratory moisture content testing shall be performed using the Oven Method (ASTM D 2216), at an oven temperature of 60 degrees Celsius. Standard Proctor moisture-density relationship (ASTM D 698) testing shall be performed at a minimum frequency of one test for every 50,000 cubic yards of material placed. As previously mentioned, additional standard Proctor samples shall be obtained and tested if one-point Proctor testing indicates that the estimated maximum dry density of the material varies by more than 5 pcf from the nearest representative standard Proctor moisture-density relationship as determined by the one-point Proctor method. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 11 December 2015 (Rev.1) 2.1.10 Cover Requirements 2.1.10.1 Operational Cover Operational soil cover should be applied, as needed, for dust control and stormwater management. If needed, operational soil cover should be applied at a thickness suited to its purpose. For example, operational soil cover may be applied thinner to provide dust control and it may be applied thicker to tolerate erosion. Operational covers to provide dust control shall be as described in the Dust Control Plan in Attachment 1. Downdrains, tack-on benches, and chimney drains will be installed and extended as appropriate. Soil diversion berms will be used to direct water as appropriate. Waste will be covered with interim and final cover as applicable, in accordance with the following sections in this plan. Operational soil cover is not required, provided the Dust Control Plan included as Attachment 1 is followed. 2.1.10.2 Interim Cover A 12-inch thick interim cover layer shall be placed on exterior slopes and areas where final grades have been reached and/or areas where waste placement will be inactive for 12 months or more. Interim cover will be seeded within 7 days in accordance with Erosion and Sediment Control requirements. Vegetation shall be removed and the interim cover soil shall be scarified or removed prior to placing any overlying waste. 2.1.10.3 Final Cover The final cover system for the Sutton Onsite CCR Landfill will be completed within 180 days following the beginning of closure activities unless otherwise approved by the Division. The final cover will consist of (from top to bottom): (i) 6-in thick vegetative cover; (ii) 18-in thick cap protective layer; (iii) geocomposite drainage layer; (iv) 40-mil thick double-sided textured linear low density polyethylene (LLDPE) geomembrane; and (v) 6-in thick intermediate soil cover/bedding layer. Should grading be required prior to closure, the final cover system (beginning with LLDPE geomembrane) may be installed directly on waste. The vegetative layer will consist of on-site soil suitable for maintaining grass cover and controlling erosion. Surface water that percolates through the vegetative layer and 18-inch thick compacted soil layer will be collected by the geocomposite drainage layer. The cover system stormwater management structures will collect both infiltration and surface water runoff. The final cover will be vegetated with native grasses within six months following closure. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 12 December 2015 (Rev.1) Refer to the Closure/Post-Closure Plan for final cover specifications and maintenance and operations requirements (Attachment 2). 2.2 Leachate and Contact Water Management As previously described, the landfill has been designed to provide separation of contact water from non-contact water. Contact water will be treated as leachate; however, the method of conveyance varies depending on the contributing source of the contact water. Generally, leachate can be described as liquid which has percolated through the waste mass and is collected by the geocomposite drainage layer along the bottom of the landfill. Contact water can be described as being generated from the following sources: • Exposed waste within the landfill (Source 1); • Slope access roads surfaced with bottom ash (Source 2); and • Perimeter access roads between the point of landfill egress and the CCR Basins (Source 3). 2.2.1 Contact Water Source 1 Contact water source 1 consists of water which has contacted exposed waste within the landfill. Exposed waste within the landfill will be graded to drain towards vertical chimney drains which will then convey the contact water into the leachate collection system. 2.2.2 Contact Water Source 2 Contact water source 2 consists of water which has contacted the slope access roads. Slope access roads provide access from the perimeter access road to the active landfill face. The slope access roads will be used as haul roads during operations and will be located at the final buildout slope access road locations. During operations, slope access roads may be surfaced with CCR; therefore, water runoff from the slope access roads will be treated as contact water. The slope access roads which terminate at the perimeter access road will convey contact water to contact water conveyance zones. Tack-on benches will extend parallel to the slope access road ditches to intercept non-contact water from up-gradient slopes. 2.2.3 Contact Water Source 3 Contact water source 3 consists of water which has contacted perimeter access roads between the point of landfill egress and the Sutton CCR basins. This definition of contact water addresses the potential for waste to be tracked onto perimeter access roads as trucks leave the active face of the landfill between the point of egress and the CCR Basins. CCR to be disposed of in the Sutton CCR Landfill will primarily originate from the onsite CCR basins; therefore, a wheel wash is not deemed necessary for landfill operations. However, Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 13 December 2015 (Rev.1) care will be exercised to minimize CCR tracking outside of the landfill and CCR basins footprint. Additionally, upon closure of the Sutton CCR basins, haul roads and perimeter access roads will be mitigated accordingly. 2.3 Leachate Collection System (LCS) The leachate collection system has been designed to meet the performance criteria of providing less than 1 foot of leachate head on the liner system under normal operating conditions and conveying contact water run-off generated by the 25-year, 24-hour storm event. The leachate collection system generally consists of the following components: • Leachate collection system pipes and drainage layers within the landfill; • Sumps at the low points of each phase of the landfill; • Force main and appurtenant structures (pumps, valves, etc.); • Leachate storage tanks; and • Leachate load out facility. Each landfill cell is equipped with leachate collection system (LCS) pipes located directly above the geocomposite drainage layer that collect infiltration, chimney drain flows, and contact water flows. The LCS pipes convey leachate and contact stormwater flows by gravity to collection sumps for removal. Clean-outs have been provided at the ends of the leachate header pipes in the event that the leachate collection and removal pipes become clogged. Sumps are located at the low point of the landfill cells. Cells 1 through 11 will have one sump each, which will convey leachate to the leachate force main via side slope risers and pumps. Sutton CCR Landfill was designed with one dually contained leachate force main connecting each cell to the leachate storage area. Leachate from the landfill will be stored temporarily at the on-site leachate storage area. The on-site leachate storage area will consist of temporary or permanent above-ground leachate storage tanks with secondary containment. The leachate storage tanks will provide enough capacity to store 3 days of leachate generation, at the peak daily leachate generation rate for the landfill. Tanker trucks will transport leachate from Sutton to a wastewater treatment plant periodically for off-site treatment and disposal. The leachate storage area is located to the northeast corner of the Sutton CCR Landfill. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 14 December 2015 (Rev.1) 2.3.1 LCS Maintenance The maintenance of the leachate management system's physical facilities (e.g., high-density polyethylene (HDPE) piping, leachate storage area) and records will be performed by or under the direct supervision of the Owner. Visual observations of the LCS system performance will be made monthly to verify that the LCS is performing properly. Clean-out pipes are located on the LCS leachate lateral and header pipes. LCS pipes will be cleaned out by the use of a clean-out snake or high-pressure water flushing at least once a year, and the LCS piping will be camera-inspected on a 5-year frequency or sooner if cleaning indicates a blockage in the leachate collection system pipes. A request to modify the frequency of clean-out and camera inspections may be granted by the Division based on consecutive inspection results and observed operating conditions. 2.3.2 LCS Record Keeping and Sampling Records will be maintained documenting the leachate line maintenance. A composite sample of untreated leachate will be sampled and analyzed at least semi-annually. The composite sample will be collected from the leachate storage area and analyzed for the same constituents in the approved monitoring plan. Results will be submitted to the Section concurrent with groundwater test results. 2.3.3 Leak Detection System (LDS) A leak detection system (LDS) has been incorporated into the design of the landfill. The LDS consists of a secondary 60 mil HDPE liner system overlain by a secondary geocomposite drainage layer connected to a LDS sump. Flow collected in the sump will be transferred to the leachate storage area via the leachate force main. The LDS sump shall be equipped with a dedicated pump system. The LDS pump system contains one low-flow pump. The LDS pump system shall operate automatically based on level switches with a low level cutoff and high level run-start activation. Additionally, a high level alarm shall be in place which will also have a high level activation. See the table below for LDS specific sump operations levels. The LDS system control panels will be equipped with visual and audible alarms programmed to identify sump liquid levels. The alarms will be equipped with a test function. The management of the leak detection system’s physical facilities (consisting of piping and flow meters) and records of monitoring will be performed by or under the direct supervision of Duke. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 15 December 2015 (Rev.1) 2.3.4 LDS Maintenance Periodic equipment maintenance shall be performed as recommended by the equipment manufacturer. Equipment maintenance will consist of checking pumps, flow meters, valves, connections, and other system equipment for leaks, corrosion, wear, scale buildup, improper functioning, and other improper operations. Appropriate corrective measures shall be taken when equipment is not operating properly. Observations shall be made weekly to confirm the proper LDS system performance. Weekly observations shall include, but not be limited to, checking pump function, verifying flow meter function, testing visual and audible alarms, and monitoring for leaks. Cleanout pipes are located at the ends of the LDS leachate header pipes. Leachate collection pipes can be cleaned by flushing with high-pressure water from a hose or by snaking in the case of severe blockages. 2.3.5 LDS Record Keeping and Monitoring Flow will be measured at the discharge of the LDS sump by a totalizing flow meter. The facility shall maintain records of monthly flow rate data from the LDS sump from the activation of the cell drainage system and until the waste height reaches approximately 40 feet. From that point, flow rate data shall be collected on a quarterly basis until landfill closure. Annual monitoring is required during the post-closure care period. If the liquid levels in the sump stays below the pump high level run-start (no pump flow) for more than 1 year, then flow rates can be recorded annually. However, if at any time during post-closure care the pump high level run-start level is exceeded on the semi-annual or annual schedules, the facility must return to monthly monitoring, until such time as the liquid level remains below the pump high-level run start activation level for two consecutive months. The purpose of LDS monitoring is to monitor if the leakage rates have been exceeded. To determine if exceedances of the leakage rates have occurred, the facility must convert monitored data to an average daily flow rate for the cell (in gallons per acre per day, gpad). For example, the average daily flow rate in gpad is equal to the total monthly flow rate divided by the number of days in the month, divided by the area of the cell in acres. If a leakage rate is exceeded, then the Division must be notified. 2.3.6 LDS Response Action Plan The purpose of the response action plan is to describe the necessary course of action in the event the Initial Response Leakage Rate (IRLR) and/or the Action Leakage Rate (ALR) are exceeded. In the event either the Initial Response Leakage Rate and or Action Leakage Rate is exceeded, the following actions will be completed. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 16 December 2015 (Rev.1) 2.3.6.1 Initial Response Leakage Rate Exceedance The Initial Response Leakage Rate (IRLR) is 108 gallons per acre per day (assuming two 2- mm diameter holes per acre); for the approximately 10-acre cells of the Sutton CCR Landfill. Should the ILR be exceeded, the following steps shall be taken: 1. Review physical equipment (pump and flow meter) function and data to confirm flow readings. Review operations to evaluate where operating equipment may have contacted the landfill liner or how landfill operations may have influenced the exceedance. If the exceedance is confirmed, the cell LDS flow shall be recorded daily. Should the daily monitored LDS flow exceed the IRLR or ALR after the initial exceedance, operational responses may include: the reduction of active face area; grading to provide improved drainage; and/or, the addition of interim soil cover. 2. Within 14 days of identifying that a leakage rate has been exceeded, the facility shall contact the Division in writing. Daily LDS flow recording shall continue. Should none of the daily measured LDS flow rates exceed the leakage rate within 14 days of initial identification of the exceedance, monthly LDS flow averaging shall resume. 3. Within 30 days of identifying that a leakage rate has been exceeded, the facility shall submit to the Division a written preliminary assessment which shall include at a minimum: • the amount of the liquid exceedance including initial measurement and daily measurements, if necessary, to date; • likely sources of the liquids; • the possible leak location; • the possible leak size; • the probable cause of the leak; and • an outline of the short-term actions being taken and planned. 4. To the extent practicable, evaluate the location, size and cause of the leak; and assess the potential for leakage escaping into the environment and its mobility. Leachate quality shall be sampled, including a chemical analysis of LDS fluids, to evaluate potential hazards (pH and RCRA metals). 2.3.6.2 Action Leakage Rate Exceedance The Action Leakage Rate (ALR) is 216 gallons per acre per day (assuming two 2-mm diameter holes per acre); for an approximately 10-acre cells at the Sutton CCR Landfill. Should the ALR be exceeded, the following steps shall be taken: 1. Review physical equipment (pump and flow meter) function and data to confirm flow readings. Review operations to evaluate where operating equipment may have contacted the landfill liner or how landfill operations may have influenced the Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 17 December 2015 (Rev.1) exceedance. If the exceedance is confirmed, the cell LDS flow shall be recorded daily. Should the daily monitored LDS flow exceed the IRLR or ALR after the initial exceedance, operational responses may include: the reduction of active face area; grading to provide improved drainage; and/or, the addition of interim soil cover. 2. Within 14 days of identifying that a leakage rate has been exceeded, the facility shall contact the Division in writing. Daily LDS flow recording shall continue. Should none of the daily measured LDS flow rates exceed the leakage rate within 14 days of initial identification of the exceedance, monthly LDS flow averaging shall resume. 3. Within 30 days of identifying that a leakage rate has been exceeded, the facility shall submit to the Division a written preliminary assessment which shall include at a minimum: • the amount of the liquid exceedance including initial measurement and daily measurements, if necessary, to date; • likely sources of the liquids; • the possible leak location; • the possible leak size; • the probable cause of the leak; and • an outline of the short-term actions being taken and planned. 4. To the extent practicable, evaluate the location, size and cause of the leak; and assess the potential for leakage escaping into the environment and its mobility. Leachate quality shall be sampled, including a chemical analysis of LDS fluids, to evaluate potential hazards (pH and RCRA metals). 5. When the ALR is exceeded, establish whether or not the unit should be closed or receipt of waste should be curtailed; and conclude whether waste should be removed from the unit for inspection, engineered controls, or repair of the liner and drainage system. Evaluate and prepare to implement what other short-term or long-term measures shall be taken to mitigate or stop any leaks according to the stage (early operations, middle operations, or closed) of landfill development. Within 60 days of identifying that the ALR has been exceeded, submit to the Division the results of the evaluation performed and any actions taken as described above, and any further measures planned. For as long as there is an exceedance of the action leakage rate, the owner or operator shall submit monthly reports to the Division summarizing the results of the remedial actions taken and further actions planned. 2.3.7 Contingency Plan The leachate storage tanks will be provided with water level instrumentation and controls in order to monitor and maintain sufficient storage capacity at all times. the design leachate storage capacity (i.e., 5-day storage contingency) combined with operational actions taken in Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 18 December 2015 (Rev.1) advance of major storm events will provide for adequate leachate storage capacity under most conditions. Operational actions will include drawing down the levels in the leachate storage tanks as much as practical in advance of an anticipated storm or large rainfall event to maximize the dry storage volume available during the event. During and immediately after a storm event, leachate removal and storage tank drawdown will be maximized to obtain low leachate levels within the storage area until leachate production levels return to normal. Other Contingencies, such as lining up alternate leachate transporters, alternate treatment facilities, installation of temporary cover systems to minimize infiltration, procurement of frac tanks for temporary storage, etc. will be maintained in the operational record. 2.4 Stormwater Collection Conveyance Stormwater that does not come in contact with waste will be treated as non-contact water. Non-contact water will be managed separately from contact water and may be used for dust control or other operational purposes. The stormwater collection system has been designed to pass the 25-year, 24-hour storm event, and generally consists of the following components: • Surface water swales; • Downdrains; • Perimeter ditches; and • Surface water basins. Interim cover will be placed over waste at the exterior side slopes. Swales will be graded into the side slopes to convey non-contact surface water from the exterior side slopes to downdrains. The swales and downdrains will be constructed and extended as operations progress. The downdrains discharge to perimeter ditches, which convey surface water to surface water basins located north and south of the Sutton CCR Landfill. An interim surface water basin will be constructed with Phase 2 along the southern portion of the landfill. Stormwater collection and conveyance measures will be inspected every 7 days and within 24 hours of rainfall events of 0.5 inches or greater, and maintained such that necessary repairs can be made as early as practical. 2.4.1 Stormwater Discharge The stormwater system at the landfill was designed to assist in prevention of the discharge of pollutants. Landfill operation shall not cause a discharge of pollutants into waters of the United States, including wetlands, that violates any requirement of the Clean Water Act, including, but not limited to NPDES requirements, pursuant to Section 402. In addition, Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 19 December 2015 (Rev.1) under the requirements of Section 404 of the Clean Water Act, the discharge of dredged or fill material into waters of the state that would be in violation of the requirements shall not be allowed by landfill operations. Operations at the landfill shall not cause the discharge of a non-point source of pollution to waters of the United States, including wetlands, that violates any requirement of an area- wide or statewide water quality management plan that has been approved under Section 208 or 319 of the Clean Water Act, as amended. 2.5 Surface Water Basin Maintenance Requirements All stormwater features (e.g., diversion ditches, berms, risers, discharge pipes, contact water conveyance zones) will be inspected every 7 days and within 24 hours of rainfall events of 0.5 inches or greater, and documented monthly for signs of damage, settlement, clogging, silt buildup, or washouts. If necessary, repairs to stormwater control features will be made as early as practical. 2.6 Groundwater Monitoring Well Access Requirements Groundwater monitoring wells are located around the landfill perimeter. A readily accessible, unobstructed path shall be maintained so that monitoring wells may be accessed using four-wheel drive vehicles. Care must be taken around the wells to prevent any damage to the wells. 2.7 Landfill Gas Management Because of the nature of the waste to be placed in the Sutton CCR Landfill, the Owner does not anticipate that methane or hydrogen sulfide gas will be generated or that odor will be an issue during operations. Therefore, landfill gas monitoring and management is not proposed. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 20 December 2015 (Rev.1) 3 EROSION AND SEDIMENTATION CONTROL Erosion and sedimentation control (E&SC) during landfill operations will consist of monitoring and repairing E&SC stormwater conveyance features and surface erosion as defined in this Operations Plan and the active Erosion and Sediment Control Plan. 3.1 E&SC Measures Monitoring and Maintenance Erosion control principles include: • Disturbing as little area as practical at any one time for landfilling operations. • Seeding/mulching of disturbed areas commencing as soon as practically possible. Employing erosion control matting or seeding and mulch on steep slopes and other erosion prone areas. • Use of earthen berms, hay bales, wattles, silt fences, riprap, or equivalent devices downgradient of disturbed areas, stockpiles, drainage pipe inlets and outlets, and at intervals along grassed waterways, until such time as permanent vegetation is established. • Placement of riprap at the inlets and outlets of stormwater piping. Erosion and sedimentation control structures include stormwater best management practice (BMP) systems, sediment basins, ash runoff basins, contact water conveyance zones, and channels. Stormwater BMP’s, sediment basins, and ash runoff basins shall be inspected every 7 days and within 24 hours of rainfall events of 0.5 inches or greater. Sediment shall be removed from each structure when sediment accumulates to one half of the design depth. Sediment removal shall bring BMP’s to their original design depth. The BMP’s, sediment basins, embankments, spillways and outlets shall also be observed for erosion damage. Necessary repairs shall be made immediately. Trash or debris within the riser structures or outfalls shall be removed. Channels shall be observed for damage every 7 days and within 24 hours or rainfall events of 0.5 inches or greater. Riprap-lined channels and outlet protection aprons used to prevent damage to channel vegetation shall be observed for washouts. Riprap shall be added to these areas, as needed, to maintain the integrity of the structure. Embankment slopes shall be inspected for erosion every 7 days and within 24 hours of rainfall events of 0.5 inches or greater. The embankment slopes shall be mowed at least four times a year. The embankment slopes shall be refertilized in the second year unless vegetation growth is fully adequate. Damaged areas shall be reseeded, fertilized and mulched immediately. Seeding, fertilizing, and mulching shall be in accordance with the Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 21 December 2015 (Rev.1) North Carolina Erosion and Sedimentation Control Guidelines and in accordance with the active Erosion and Sediment Control Permit. Ground stabilization shall be performed within 7 calendar days on perimeter areas and slopes greater than 3H:1V. Ground stabilization shall be performed within 14 calendar days in other areas. Seedbed preparation, seeding, soil amendments, and mulching for the establishment of vegetative ground cover will be applied in accordance with North Carolina Erosion and Sedimentation Control Guidelines. 3.2 Surface Erosion Monitoring Adequate erosion control measures shall be established to help prevent sediment from leaving the site. Channels will be observed once every seven days and within 24 hours after any rainfall event of 0.5 inches or greater. Slopes will be periodically checked for erosion and vegetative quality, fertilized, and mowed. A slope or portion thereof shall be identified as needing maintenance if it meets any one of the following conditions: • Exposed waste on exterior slopes; • Areas of cracking, sliding, or sloughing; or • Areas of seepage. Slopes identified as needing maintenance shall be repaired as soon as practical and as appropriate to correct deficiencies. Repair activities may include re-dressing the slope, filling in low areas, and/or seeding. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 22 December 2015 (Rev.1) 4 VEGETATION MANAGEMENT Within six months after final termination of disposal operations at the site, the area shall be stabilized with vegetation as required by design drawings and Closure/Post-Closure Plan. Temporary seeding will be applied, as required. Temporary erosion control measures may be required until permanent cover is established. Mulching, until a vegetative cover is established, can stabilize areas where final grades have been reached. Soil mulching can be achieved using wood chips, straw, hay, asphalt emulsion, jute matting, and synthetic fibers. Mulches allow for greater water retention; reduce the amount of runoff; retain seeds, fertilizer, and lime in place; and improve soil moisture and temperature conditions. 4.1 Temporary Seeding Temporary seeding and soil amendments will be applied as follows: Common Name Botanical Name Rate Purpose Optimal Planting Dates Warm Season German Millet Setaria Italica 10 Nurse Crop 4/15 - 8/15 Cool Season Rye Grain Secale Cereale 10 Nurse Crop 8/15 - 4/15 Big Bluestem Andropgon Geradii / Earl 7 Primary Stabilization 12/1 - 5/1 Switchgrass Panicum Virgatum / Blackwell, Shelter, Or Carthage 3.5 Primary Stabilization 12/1 - 4/1 Virginia Wild Rye Elymus Virginicus 6 Primary Stabilization 2/15 - 3/20 And 9/1 - 11/1 Indian Woodoats Chasmanthium Latifolium 2.5 Primary Stabilization 2/15 - 3/20 And 9/1 - 11/1 Soil Amendments Pounds Per Acre Agricultural limestone 2,000 Fertilizer (10-10-10) 1,000 Mulch 4,000 Note: Soil amendments are for all-season temporary seeding applications. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 23 December 2015 (Rev.1) 4.2 Permanent Seeding Permanent seeding will be utilized to reduce erosion and decrease sediment yield from disturbed areas, to permanently stabilize such areas in a manner that is economical, adapts to site conditions, and allow selection of the most appropriate plant materials. Seeding recommendations from Tables 6.11a, 6.11b, and 6.11c (NCESC Design Manual, 2013) list herbaceous plants recommended for use as nurse crops for immediate stabilization and primary crops for initial and long-term stabilization. Nurse crops are expected to develop in two to five weeks and, with adequate maintenance, be an effective method of soil stabilization for a period of six months to one year. Primary crops develop over a three- week to one-year period and are effective up to three years with a well-defined maintenance program. These tables were utilized to select a nurse crop and primary crop seed mix best suited for site conditions. Permanent seeding may be applied to landfill side slopes, drainage channels, as indicated on the Permit Drawings and in accordance with the Technical Specifications. Soil Amendments Pounds Per Acre Agricultural limestone 4,000 Fertilizer (10-10-10) 1,000 Mulch 4,000 Note: Perform soil test to determine proper soil amendments; if not available, use the quantities above. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 24 December 2015 (Rev.1) 5 LANDFILL CLOSURE The Sutton CCR Landfill will be closed in accordance with the design drawings and Closure/Post-Closure Plan. The Closure/Post-Closure Plan outlines the sequence for closing the landfill and the post-closure maintenance activities. Closure is designed to minimize the need for long-term maintenance and to control the post-closure release of contaminants. Closure activities may be revised as appropriate for materials, specifications, technology advancements, or changes in regulations at the time the landfill is closed or in post-closure. In general, the landfill development is designed so that final cover can be established as soon as possible. Operations Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Operations Plan -Sutton LF-TR-01.docx 25 December 2015 (Rev.1) 6 REQUIRED REGULATORY SUBMITTALS Submittal Requirement Reporting/Action Frequency Groundwater Monitoring Reports Maintain a record of all monitoring events and analytical data in accordance with the Groundwater Monitoring Plan. Reports of the analytical data for each water quality monitoring sampling event shall be submitted to DENR Division of Waste Management (DWM) in a timely manner. Semiannually Annual Tonnage Reports Tons of waste received and disposed of in the landfill shall be reported to the DWM and to all counties from which waste was accepted on forms prescribed by the DWM. Refer to the Permit to Operate for annual reporting requirement information. Annually Must submit no later than August 1 each year 10-Year Waste Management Plan Per North Carolina G.S. 130A-309.09D (c): • A 10-year waste management plan shall be developed for this landfill and submitted to DWM. • The plan shall be updated and submitted to DWM at least every three years. • A report on the implementation of the plan is required to be submitted to DWM by August 1 of each year. 10-year plan prepared every 10 years 10-year plan updated every 3 years Implementation report annually ATTACHMENT 1 Dust Control Plan Prepared for Duke Energy Corporation, LLC 526 South Church Street Charlotte, North Carolina 28202 DUST CONTROL PLAN L.V. SUTTON ENERGY COMPLEX ONSITE COAL COMBUSTION RESIDUALS LANDFILL Wilmington, North Carolina Prepared by 1300 South Mint Street, Suite 410 Charlotte, North Carolina 28203 Authorization No. 4321 Project Number GC5770 August 2015 ____________________________ Victor M. Damasceno, Ph.D., P.E. North Carolina Registration No. 042284 Date: _______________ Dust Control Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Attachment 1 - Dust Control Plan.docx i August 2015 TABLE OF CONTENTS 1 INTRODUCTION AND SITE DESCRIPTION ........................................................ 1 2 DUST CONTROL METHODS ................................................................................... 2 3 MONITORING AND CORRECTIVE ACTION RESPONSE ................................ 4 3.1 Monitoring ............................................................................................................. 4 3.2 Corrective Action ................................................................................................... 4 LIST OF ATTACHMENTS Attachment A – Template: Monitoring Worksheet Dust Control Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Attachment 1 - Dust Control Plan.docx 1 August 2015 1 INTRODUCTION AND SITE DESCRIPTION This Dust Control Plan is for the L.V. Sutton Energy Complex (Sutton) Onsite Coal Combustion Residuals (CCR) Landfill. This Plan provides dust control methods for managing dust emissions at the landfill. This Plan also provides a monitoring program and corrective action response procedure to help contain CCRs on site and to prevent dust nuisances to employees and the public. The monitoring program will aid Duke Energy Progress (Duke) and the landfill operator in evaluating the dust control methods, or combination of dust control methods, that prove effective for the site specific conditions. This Dust Control Plan addresses operations of Phases 1, 2, and 3 of the Sutton CCR Landfill. The landfill has an approximate 140-acre footprint of which approximately 100- acres is for waste containment. The Sutton CCR Landfill is used for CCR management. CCRs primarily consist of fly ash, bottom ash, pyrites and coal mill rejects, boiler slag, wastewater treatment sludge, sand blast material, and coal waste. This Plan is included as an Attachment to the landfill Operations Plan. Dust Control Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Attachment 1 - Dust Control Plan.docx 2 August 2015 2 DUST CONTROL METHODS The primary potential sources of dust emissions at the landfill are at the top deck area and at the active area of waste placement. These areas are at a higher risk for producing dust due to vehicular and equipment traffic and earthwork-related construction. Exterior landfill slopes are less of a dust control concern, as they have intermediate or operational soil covers which are vegetated as described in the Operations Plan. Dust emissions from the landfill can be controlled through a variety of dust control methods. Possible dust control methods are identified herein. Dust control methods may be characterized as products and/or applications, structural wind breaks and/or covers, and operational methods. Dust control methods for the landfill area include:  Watering;  Establishing vegetative cover;  Mulching;  Structural controls consisting of: • Wind breaks (e.g., fencing and/or berms), and • Temporary coverings (e.g., tarps);  Spray applied dust suppressants consisting of, but not limited to: • Anionic asphalt emulsion, • Latex emulsion, • Resin in water, • Polymer based emulsion, and • Mineral mortar coatings (i.e. posi-shell);  Calcium chloride;  Soil stabilizers (i.e. soil cements);  Operational soil cover;  Modifying the active working area; and  Modifying operations during dry and windy conditions. The operator may use, and is not limited to, combinations of these dust control methods or any method that maintains safety and is technically sound to control dust for the specific site conditions. If the operator intends to use a dust control method not presented above, the proposed dust control method will be evaluated on a case by case basis to assess the effectiveness with specific site conditions. For the purposes of this Plan, operational soil cover will be defined as soil material applied at a suitable thickness to provide dust control. Dust Control Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Attachment 1 - Dust Control Plan.docx 3 August 2015 The effectiveness of the dust control methods implemented should be evaluated through a dust monitoring program as described in Section 3. Operational equipment is generally anticipated to include dump trucks, vibratory smooth drum rollers, sheepsfoot compactors, bulldozers, water trucks, spray trailers, track hoes, and service trucks. Operational equipment will be used to construct, install, apply, and/or repair dust control methods. The operator will make provisions to alleviate any on-site issues that arise when primary equipment is being maintained or is inoperable. The landfill operator will make provisions to have the necessary equipment to control multiple fugitive CCR dusting emission events. Dust Control Plan L.V. Sutton Energy Complex Onsite CCR Landfill GC5770\Attachment 1 - Dust Control Plan.docx 4 August 2015 3 MONITORING AND CORRECTIVE ACTION RESPONSE This section describes a dust monitoring program and suggests corrective action responses should fugitive emissions be observed. 3.1 Monitoring During landfill operations, a dust monitoring program will be implemented to evaluate the dust control measure performance and observe the areas for dust emissions. The dust monitoring program consists of performing visual observations of dust prone areas, dust control measures, and monitoring existing and forecasted weather conditions. Dust emissions can occur under many weather conditions. For the purposes of this Plan, dust emissions are characterized as fugitive emissions, where CCR dust is located outside the limits of the landfill waste. This is most likely to occur during windy, dry, and hot weather conditions; therefore, the operator will monitor both existing and forecasted weather conditions and use dust control measures suited to the weather conditions. The dust control measures shall be implemented prior to the forecasted weather conditions. Equipment operators shall continuously observe the active face and other areas within the landfill limit for dust emissions. In addition, preventative dust control measures should be observed and documented at least twice daily (morning and afternoon) when the landfill is in operation to evaluate the dust control measure performance. Additional observations may be necessary as site and weather conditions dictate. Observations will be documented on the attached “Monitoring Worksheet,” online database/worksheet, etc. Due to the continual maintenance necessary on moisture conditioned and spray-applied areas, the operator shall pay particular attention to these areas. Structural controls shall be observed to monitor that they are achieving their intended purpose. Monitoring will be conducted during times when the landfill is in operations. The operator shall continue to provide necessary dust control measures during periods when operations are inactive (e.g., outages, weekends, and holidays). Operators are to establish appropriate measures so that dust emissions are not reasonably likely to occur during inactive operations periods when monitoring is not being conducted. 3.2 Corrective Action If fugitive dust emissions are observed, and observations indicate that dust control measures are not achieving their intended purpose, then appropriate corrective actions will be taken. Dust control measures should be reapplied, repaired, or added, as necessary, to control dust emissions. The operator will construct, install, apply, and/or repair dust control measures prior to the end of the work day to control dust emissions during non-operating hours. The operator will implement dust control measures as preventative controls rather than in response to fugitive dust emissions. ATTACHMENT A Template: Monitoring Worksheet Dust Control Plan L.V. Sutton Energy Complex Onsite CCR Landfill Month: Year: Site Name: Actively working? 1 Weather 2, 7, 8 Method(s) Used to Control Dust 3 *Is dust present? 4 *Is erosion present? 5 Preventative or Corrective Action Taken Initials Yes/No Temperature range, rainfall data, wind speeds, dry/damp,etc. Currently Percipitating (Y/N) Water Truck Active (Y/N) Alternative Cover Material in Place Other Examples: Added more water, applied additional alternative cover material, contacted Plant DR, etc.* Yes No Yes No AM PM AM PM AM PM AM PM AM PM AM PM AM PM Notes: 1. Actively working indicates several factors at the site. YES: indicates the waste cell is receiving ash for disposal or material and/or equipment is operational on the day of inspection NO: indicates the waste cell is not operational, no maintenance work or equipment movement is occurring on the day of inspection. 2. Weather data should be secured from the weather station that is operating at the job trailer. Take readings from the display panel just before the inspection is conducted and make a note of it for the time and date the inspection is being performed. If the weather station is inoperable at the time of inspection, observed conditions should be entered with a note that the weather station was inoperable. 3. Indicate actual method actively being utilized for dust control and frequency if applicable. (ie: EcoUltimate in place, EcoUltimate applied in am, water truck running, rainfall sufficient for moisture, etc) 4. Is dust present? YES: indicates that dust is visible at time of inspection. If yes is indicated, there should be preventative/corrective action noted. NO: indicates that dust is not visible at the time of inspection. 5. Is erosion present?: YES: indicates erosion (or new erosion) is present at the time of inspection. If yes is indicated, there should be preventative/corrective action noted.(existing erosion should be noted as corrective action until complete) NO: indicates that no erosion is present at the time of inspection. 6. Each date has two lines for input data. The morning inspection is to be placed in the top row for that date and the afternoon inspection results should be placed in the second. 7. Make sure all data placed in the inspection report above, lines up with any other daily reports you may be completing for your operations, such as erosion and sediment control inspection forms, waste acceptance forms, daily reports and/or logs, etc. 8. Reference the erosion and sediment control inspection forms for rainfall event totals. ATTACHMENT 2 Closure/Post-Closure Plan (Submitted under separate cover) Prepared for Duke Energy Progress, LLC 526 South Church Street Charlotte, North Carolina 28202 CLOSURE AND POST-CLOSURE CARE PLAN L.V. SUTTON ENERGY COMPLEX ONSITE COAL COMBUSTION RESIDUALS LANDFILL Wilmington, North Carolina Prepared by Geosyntec Consultants of NC, PC 1300 South Mint Street, Suite 410 Charlotte, North Carolina 28203 Licence No. C-3500 Project No. GC5770 August 2015 _____________________________ Victor M. Damasceno, Ph.D., P.E. North Carolina Registration No. 042284 Date:__________________ ____________________________________________________________ iiiiiiiiiiiiiiiiictctctctctctctctctccccccccororrrrrrrrr MMMMMMMMM CaCCCCCCCrolillllna _ P 2 ________________________________________ate: j AuAuAuuguguguststst 220 __________________________________________________________________________ M. DaDaDaDamamamamascscseneoo,,PhPhPhhPhPhPhPhPhPhPhhPhhP.D.DD.D.,,.,PP a RRegegeggisisistrrratatattioioion n n nn nnnnn NoNoNoNNoNNNNNNNNN..0404040422 L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx i August 2015 TABLE OF CONTENTS 1 INTRODUCTION....................................................................................................................2 2 PROJECT DESCRIPTION ....................................................................................................2 3 CLOSURE SCHEDULE .........................................................................................................2 3.1 Introduction .....................................................................................................................2 3.2 Placement of Final Cover ................................................................................................3 3.3 Closure Certification .......................................................................................................4 3.4 Record Keeping ...............................................................................................................4 4 FINAL COVER SYSTEM DESIGN ......................................................................................4 4.1 Introduction .....................................................................................................................4 4.2 Final Cover System Components ....................................................................................4 4.3 Final Cover System Materials .........................................................................................5 4.3.1 Vegetation .............................................................................................................5 4.3.2 Vegetative and Protective Soil Layers ..................................................................5 4.3.3 Geocomposite Drainage Layer .............................................................................5 4.3.4 Geomembrane .......................................................................................................6 4.4 Final Cover System Construction Procedure ..................................................................6 4.5 Final Cover System Stability ...........................................................................................6 4.6 Final Cover Settlement ....................................................................................................7 4.7 Final Cover Drainage System ..........................................................................................7 4.8 Surface Water Drainage System ......................................................................................7 4.9 Erosional Stability ...........................................................................................................8 5 POST-CLOSURE ACTIVITIES ............................................................................................8 5.1 Contact .............................................................................................................................8 5.2 Post-Closure Maintenance ...............................................................................................9 5.3 Inspection Plan ................................................................................................................9 5.4 Cap System Integrity .....................................................................................................10 5.5 Monitoring Plan .............................................................................................................10 5.6 Post Closure Land Use ..................................................................................................10 5.7 Completion of Post Closure Care ..................................................................................10 6 FINANCIAL ASSURANCE .................................................................................................10 L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 2 August 2015 1 INTRODUCTION This Closure and Post-Closure Care Plan (Plan) is submitted as part of the Permit Application Report to Construct and Operate (Permit Application Report) the Onsite CCR Landfill at L.V. Sutton Energy Complex (Sutton), located in Wilmington, North Carolina. This plan has been prepared for Duke Energy Progress, LLC. (DEP) pursuant to Rule 15A of the North Carolina Administrative Code (NACA), Subchapter 13B. 2 PROJECT DESCRIPTION The proposed onsite CCR landfill will be operated in support of closure activities of the existing CCR basins at Sutton and includes the installation of a liner and leachate collection system for the landfill. The landfill development plan includes the construction of 11 disposal cells to be constructed in three phases. The final, build-out landfill footprint will encompass approximately 140 acres of which approximately 100 acres are for waste disposal. Ancillary facilities will support the operation of the landfill and provide storm water management throughout the life of the facility. It is estimated that Phase 1 of the proposed 100-acre landfill will provide approximately 4.2 million cubic yards (approximately 5 million tons) of disposal capacity. Under final build out conditions, the landfill (i.e., Phases 1, 2, and 3) is expected to provide approximately 8.3 million cubic yards (approximately 10 million tons) of disposal capacity over a period of about 12 years. The maximum elevation of the proposed landfill will be approximately 112 ft National Geodetic Vertical Datum (NAVD88) with an average top-deck elevation equal to 108 ft NAVD88. 3 CLOSURE SCHEDULE 3.1 Introduction Following the completion of waste placement, a final cover system will be constructed. The primary purpose of a final cover system is to minimize infiltration into the waste. The proposed final cover system cross section is presented in the Construction Permit Application Drawings submitted as Appendix A of the Permit Application Report. Final closure of the landfill will commence once final design grades are achieved, DEP declares that no more waste will be accepted, or as directed by the North Carolina Department of Environment and Natural Resources (NCDENR) Division of Waste Management – Solid Waste Section (Division). DEP may elect to close the landfill incrementally during landfill operations once an area large enough to warrant cover system construction has reached final grades. Prior to beginning closure of the proposed landfill, the Owner or Operator shall notify the Division that a notice of intent to close the landfill has been placed in the operating record. Closure activities for the landfill shall begin no later than 30 days after final receipt of waste unless otherwise approved by the Division or, if the landfill has remaining capacity and there is a L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 3 August 2015 reasonable likelihood that the landfill will receive additional wastes, no later than one year after the most recent receipt of wastes. Extensions beyond the one-year deadline for beginning closure may be granted by the Division if the Owner or Operator demonstrates that the landfill has the capacity to receive additional wastes and the Owner or Operator has taken and will continue to take the steps necessary to prevent threats to human health and the environment from the unclosed landfill. The final cover system will be finished within 180 days following the beginning of closure activities unless otherwise approved by the Division. Extensions of the closure period may be granted by the Division if the Owner or Operator demonstrates that closure will, of necessity, take longer than 180 days and they have taken and will continue to take the necessary steps to prevent threats to human health and the environment from the unclosed landfill unit. The final cover system for the closed phase will be certified by a professional engineer as being completed. DEP shall record a notation on the deed to the landfill property stating that the property has been used as a landfill and its use is restricted under the Closure/Post-Closure Plan approved by the Division. The Division will be notified by DEP of the closure completion, certification, deed notation, and placement of these records into the landfill’s operating record. Following cover system construction, the landfill will be vegetated with grass and maintained. If the landfill must be closed prior to reaching the final contours, the surface of the landfill will be sloped to a minimum grade of 5 percent and maximum grade of 28.6 percent (3.5H:1V) within the footprint, or a maximum grade of 33.33 percent (3H:1V). A final cover will be established over the landfill unit being closed. The maximum waste-filled area of the proposed landfill that would require closure operations at any one time is approximately 100 acres. This closure/post- closure plan is for the closure of Phases 1, 2, and 3. 3.2 Placement of Final Cover DEP will notify the Division prior to beginning closure activities that a notice of intent to close the facility or a portion of the facility has been placed in the operating record. The following is an itemized list of activities proposed during closure and estimated timeframe following reaching design grades. Activity Proposed Timeframe (following final grades) Grade Intermediate Cover 0 - 45 Survey 20 - 60 Place Soil Cap / Geosynthetic Barrier Layer 45 - 135 Place Erosion Layer 75 - 150 Seeding/Sodding (Permanent)1 100 - 180 Prepare and Submit Closure Certification 150 - 210 Notes: 1. Depending on the time of year, seeding/sodding may need to be delayed up to three months. Temporary seeding shall be placed within the specified time frame L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 4 August 2015 3.3 Closure Certification Following closure of each disposal unit or portions of units, the owner and operator shall notify the Division that a Certification, signed by the project engineer verifying that closure has been completed in accordance with the closure plan, has been placed in the operating record. This Certification will state that the site was closed in accordance with the Closure Plan and applicable solid waste regulations and laws. 3.4 Record Keeping Following final closure of the landfill, the owner and operator shall record a notation on the facility property deed to this effect, or some other instrument that is normally examined during a title search, and notify the Division that the notation has been recorded and a copy has been placed in the operating record. The notation on the deed shall in perpetuity notify any potential purchaser of the property that the land has been used as a CCR disposal facility and its future use is restricted under the Closure Plan. 4 FINAL COVER SYSTEM DESIGN 4.1 Introduction The final cover system of the Sutton onsite CCR landfill will be constructed after final waste elevations are achieved. The landfill will have side slopes graded at 3H:1V, and top slopes graded at 5 percent to maximize runoff and minimize erosion. Drainage swales will be constructed on the final cover system to collect and divert surface water run-off via downdrain pipes to a perimeter swale at the toe of the landfill, and then to the storm water management areas (i.e., storm water ponds). This will help minimize erosion at the surface of the final cover system. The maximum final elevation of the landfill will be 112 ft NAVD88. The plans and details for the proposed final cover system are provided in the permit drawings (Appendix A of the Permit Application Report). The various components of the final cover system are discussed in the remainder of this section. 4.2 Final Cover System Components The proposed final cover system on the landfill side slopes and top slopes is presented on the permit drawings (Appendix A of the Permit Application Report). The final cover system for the proposed landfill will be constructed using industry standard construction practices, a CQA program, and quality materials. The technical specifications and CQA procedures for the cover system are included in Appendices K and L of the Permit Application Report, respectively. The proposed final cover system on the landfill top slopes is indicated on the permit drawings and consists of, from top to bottom:  0.5-ft thick vegetative layer; L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 5 August 2015  1.5-ft thick protective soil layer;  40-mil thick textured PE geomembrane; and  0.5-ft thick bedding layer/interim cover (liner can be directly on waste material if grading is not needed). The final cover system on the 3H:1V side slopes of the landfill consists of, from top to bottom:  0.5-ft thick vegetative layer;  1.5-ft thick protective soil layer;  double-sided geocomposite lateral drainage layer;  40-mil thick textured PE geomembrane; and  0.5-ft thick bedding layer/interim cover The thickness of the bedding layer/interim cover will be a function of grading activities and may be completely removed during grading activities for final cover placement. 4.3 Final Cover System Materials 4.3.1 Vegetation The surface of the final cover system will be vegetated either by seeding or sodding. The grass seed will have a high tolerance to drought. The sod will be of firm texture, having a compacted growth and good root development. The minimum requirements of the grass seed and sod are presented in the Technical Specifications (Appendix K of the Permit Application Report). 4.3.2 Vegetative and Protective Soil Layers The upper 6 inches of the final cover system will consist of loosely placed vegetative layer and will be vegetated to minimize erosion. The protective soil layer below the vegetative layer will consist of 18 inches of on-site soil (or approved equal). The protective soil layer will be compacted in the upper 6 inches during construction to inhibit root penetration into the lateral drainage layer underlying the protective soil layer on the side slopes. The minimum requirements of vegetative and protective soil layer are presented in the Technical Specifications (Appendix K of the Permit Application Report). 4.3.3 Geocomposite Drainage Layer The geocomposite lateral drainage layer on the side slopes consists of a geotextile filter, a geonet drainage layer, and a geotextile friction layer that will be placed beneath the protective soil layer on the 3H:1V side slopes. The geotextile filter, geonet drainage layer, and geotextile friction layer are bonded together to form the double-sided geocomposite drainage layer. The function of the proposed geotextile filter is to prevent soil particles of the overlying protective soil layer from penetrating and clogging the underlying geonet drainage layer. The purpose of the lateral drainage layer is to remove the infiltrated storm water that reaches the geonet and to minimize L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 6 August 2015 the potential of pore water pressure build-up in the overlying protective soil layer. The purpose of the geotextile friction layer is to increase the interface friction between the geomembrane and the geonet and thereby increase the stability of the final cover system. The requirements for the geomembrane specified for this design are included as Section 31 05 19.16 of the Technical Specifications attached as Appendix K of the Permit Application Report. 4.3.4 Geomembrane A geomembrane is proposed as a component of the final cover system to reduce infiltration of storm water through the final cover system into the waste. The specified geomembrane is a 40- mil thick textured LLDPE geomembrane. The textured surface is necessary to increase the stability of the final cover system. Specified property values for the final cover system geomembrane are provided in the Technical Specifications (Appendix K of the Permit Application Report). 4.4 Final Cover System Construction Procedure The surface of the final cover system bedding layer will be graded and compacted to prepare a smooth base for installation of the final cover geomembrane. The bedding layer/interim cover layer may be comprised of soil and/or CCR. The geomembrane and the lateral drainage layer will be terminated at the toe of the waste slope along the landfill perimeter. At the termination point, the final cover geomembrane will be welded to the geomembrane of the bottom liner system to seal the landfill. The geocomposite drainage layer will discharge into the drainage swales. The details of the final cover termination are presented in the permit drawings (Appendix A of the Permit Application Report). 4.5 Final Cover System Stability A potential failure surface within the final cover system on the side slopes of the landfill was evaluated using the veneer slope stability analysis discussed in the calculation package titled “Final Cover Veneer Slope Stability Analysis” included in Appendix M of the Permit Application Report. A parametric or sensitivity analysis was performed to establish the minimum interface friction angle () such that the calculated veneer stability FS is equal to or greater than 1.5, an acceptable requirement in accordance with the state-of-practice for landfill covers. The parametric analysis was performed by calculating the FS for various values of interface friction angle. The results of the parametric stability analyses indicate that the minimum interface friction angle required to achieve a FS of 1.5 is typical of the soil-geosynthetic and geosynthetic-geosynthetic interface friction angles reported in the literature. Prior to construction of the final cover system, the interface friction angles between the actual soil and geosynthetic materials will be verified by performing site-specific interface shear strength testing. L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 7 August 2015 4.6 Final Cover Settlement The soil components of the final cover system act as a surcharge for the underlying waste. Under this surcharge, the waste compresses and settles. Uneven total and differential settlements of the waste may adversely affect the drainage of storm water from the landfill top slopes of the final cover system. A waste settlement analysis was performed to evaluate the adequacy of the slopes and ensure positive drainage (i.e., drainage towards the top slope diversion berms or swales) along the top slopes. The calculations are presented in the calculation package titled “Final Cover Waste System Settlement Analysis” included in Appendix N of the Permit Application Report. The results of the calculations indicate that drainage is not expected to be adversely impacted due to waste settlements. Similarly, the calculated average strain values in the final cover geomembrane indicate that the geomembrane is not expected to be adversely impacted due to waste settlements. 4.7 Final Cover Drainage System The final cover drainage system on the side slopes is designed to control seepage forces in the vegetative layer and is necessary for the stability of the vegetative layer. The final cover drainage system primarily consists of a lateral drainage layer placed on top of the geomembrane barrier layer of the final cover system. This lateral drainage layer collects the water that percolates through the overlying vegetative layer and conveys the water to the drainage swales. Details of the final cover drainage system are presented in the permit drawings (Appendix A of the Permit Application Report). Computations for maximum hydraulic head in the lateral drainage layer are discussed in the calculation package titled “Final Cover System Performance Evaluation” attached as Appendix O of the Permit Application Report to this Permit Application Report. 4.8 Surface Water Drainage System The permit drawings (Appendix A of the Permit Application Report) present a storm water management plan for the proposed landfill. Drainage swales will be incorporated in the final cover system on the side slopes of the landfill as indicated in the permit drawings to collect and convey surface water run-off at non-erosive velocities and limit the length of sheet flow on the final cover to minimize the formation of erosion rills and gullies in the vegetative layer. The drainage swales will be incorporated in the final cover system approximately every 50-ft in elevation. These drainage swales will convey storm water to the downdrain pipes, and will be approximately 12.5-ft wide with a variable depth ranging from 0.5-ft (at its shallowest point) to 2.25-ft deep (at the downdrain pipes). The downdrain pipes will convey storm water from the landfill side slopes and top slopes to a perimeter swale at the toe of the landfill, and then to the storm water management areas (i.e., storm water ponds) for the site. The downdrain pipes will be 18-inch diameter double-wall L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 8 August 2015 corrugated HDPE pipes (smooth inside) buried within the 2 ft thick soil layer of the final cover system. Design calculations confirming the adequacy of the drainage swales and the downdrains to convey the storm water run-off are presented in the calculation package entitled “Final Cover Storm Water Management System Design” attached as Appendix P of the Permit Application Report. 4.9 Erosional Stability A calculation to predict erosion soil loss in the cover is presented in the calculation package titled “Final Cover System Performance Evaluation” (Appendix O of the Permit Application Report). The results of this calculation indicate that the landfill side slope and top slope vegetation adequately controls erosion of the cover. 5 POST-CLOSURE ACTIVITIES Post-closure activities will be conducted at the facility in accordance with Rule .0510 for a period of 30 years following final closure of the facility. The Division may decrease the length of the post-closure period if the owner or operator demonstrates that the reduced period is sufficient to protect human health and the environment, and the Division approves this demonstration. The period might be increased by the Division if the Division determines that the lengthened period is necessary to protect human health and the environment. The end of the closure-post closure period must be certified by a registered professional engineer. To accomplish certification over the required 30-year duration, a registered professional engineer will prepare annual certifications. The annual certifications will document that the cover system has been monitored and maintained in accordance with the Post-Closure Plan. The annual certifications shall be based on observations and results documented on regular post-closure monitoring reports, maintenance records, and compliance monitoring reports maintained in the Operating Record. 5.1 Contact The person responsible for the facility during the post-closure care period is: On-Site Environmental Professional Duke Energy Progress, LLC L.V. Sutton Energy Complex 801 Sutton Steam Road Wilmington, North Carolina (910) 341-4754 L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 9 August 2015 5.2 Post-Closure Maintenance Post-closure maintenance will be conducted at the Sutton CCR landfill for a period of 30 years after final closure. Maintenance activities will be required for the final cover system to remain functional. The vegetative cover shall be mowed a minimum of once each year. The vegetative cover shall be amended and fertilized as needed to maintain healthy vegetation. Depressions in the cover that pond water or otherwise impair the function of the final cover will be filled and/or regraded. Areas subject to regrading will be revegetated. Animal burrows and eroded areas should be filled in with compacted soil and reseeded. If vegetative cover is not adequate in a particular area, fertilizer or other soil amendments should be applied and the area reseeded in order to re-establish vegetation. Insecticides may be used to eliminate insect populations that are detrimental to the vegetation. Any deep-rooted or woody vegetation that may have established itself on the cover soil will be removed. In addition to maintenance of the vegetative cover, any items noted as requiring maintenance in Section 5.3 Inspection Plan would also require maintenance. Maintenance will include mowing at least two times per year as well as needs identified through the monitoring program will be initiated no later than 60 days after the discovery or within 24 hours if a danger or imminent threat to human health or the environment is indicated. 5.3 Inspection Plan Routine inspections will be conducted throughout the post-closure care period and documented accordingly. These inspections will be carried out quarterly unless issues are detected that indicate that more frequent visits are required. Potential impacts to the public and environment will be considered in determining the inspection frequency. Items to be included in the quarterly inspection will be as follows:  Access and security control such as fences, gates, locks, and other measures that control site and facility access  Cap system for signs of erosion, settlement, or subsidence  Condition and/or presence of vegetation (for distressed or dying vegetation or woody vegetation with potential to penetrate the low permeability barrier)  Storm water management  Leachate collection and leak detection system  Erosion and sediment control  Groundwater monitoring system  Integrity of site benchmarks  Vector control L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 10 August 2015 5.4 Cap System Integrity DEP shall maintain the integrity and effectiveness of the cap system including repairing the cover as necessary to correct the effects of settlement, subsidence, erosion, or other events, and preventing run-on and run-off from eroding or otherwise damaging the cap system. 5.5 Monitoring Plan Post-closure monitoring will be conducted at the Sutton CCR landfill for a period of 30 years after final closure. Monitoring will include: (i) semi-annual sampling of groundwater and surface water; and (ii) monthly inspection of the final cover systems for the first year and quarterly inspections thereafter. A monitoring plan which addresses groundwater monitoring has been prepared and is included as the Water Quality Monitoring Plan (Appendix J of the Permit Application Report). Groundwater monitoring shall continue throughout the post-closure care period in accordance with the Plan. 5.6 Post Closure Land Use The primary land use for the site after closure will be open dormant green space. Post-closure use of the property shall not affect the integrity of the cap system, base liner system, or any other components of the containment system, or the function of the monitoring systems unless necessary to comply with the requirements in the Solid Waste Management Rules. The Division may approve disturbance if the owner or operator demonstrated that disturbance of the cap system, base liner system, or other component of the containment system, including removal of waste, will not increase the potential threat to human health or the environment. 5.7 Completion of Post Closure Care The Division shall be notified following certification of completion of the post-closure care period for the facility and that a certification signed by a registered professional engineer licensed in the state of North Carolina, verifying that post-closure care has been completed in accordance with the post-closure plan has been placed in the operating record. 6 FINANCIAL ASSURANCE In accordance with the North Carolina Solid Waste Management Rules (15A NCAC 13B.1628) and North Carolina Session Law S.L. 2011-262, financial assurance will be provided by DEP in the form of the Corporate Financial Test (40 C.F.R. §258.74(e)). Documentation as required by 40 C.F.R. §258.74(e)(2) shall be placed in the facility operating record before the initial receipt of waste. The Director will be notified when the documentation of financial assurance has been placed in the operating record. L.V. Sutton Plant, Onsite Landfill Closure and Post-Closure Care Plan GC5770/Closure and Post-Closure Care Plan.docx 11 August 2015 After the initial placement of documentation of financial assurance as required by 40 C.F.R. §258.74(e)(2) in the facility operating record, DEP will annually update the information and place updated information in the operating record within 90 days following the close of their fiscal year. The Director may provide up to an additional 45 days if DEP can demonstrate that 90 days is insufficient time to acquire audited financial statements. Facility Name: L.V. Sutton Energy Complex, Onsite CCR Landfill Date: 11/23/15 Phase 1 (Cells 3-8)Calculated By: VMD Permit No.: Checked By: JC 1300 South Mint Street, Suite 410 Facility Address: Sutton Steam Plant Road Charlotte, North Carolina 28203 Wilmington, North Carolina Revision No.: 0 phone - 704.227.0861 Facility Owner: Duke Energy Progress, LLC Project No.: GC5770 Phase No.: 02 www.geosyntec.com CLOSURE COSTS: I. Native Soil for Slope and Fill (Site Preparation) a. Area to be capped 56.1 acre 56.1 acre b. Unit cost for recompacting and grading 750 / acre 750.00 / acre c. Cost for recompacting and grading (a x b)$42,075 d. Unit cost for subgrade preparation 500 / acre 500.00 / acre e. Cost for subgrade preparation (a x d)$28,050 o. Total native soil cost (c + e)$70,125.00 II. Topsoil a. Area to be capped 56.1 acres x 4840 yd2/acre = 271,524 yd2 b. Depth of topsoil needed 6 inches x 1 yd/ 36 inches = 0.17 yd c. Quantity of topsoil needed (a x b)45,254 yd3 d. Percentage of soil from off-site 100%100% e. Excavation unit cost (on-site material)$5.00 $5.00 /yd3 f. Purchase unit cost (off-site material)$13.00 $13.00 /yd3 g. Delivery Cost (off-site material)$12.00/yd3 for 5 mil RT $12.00 /yd3 h. Placement/Spreading unit cost included in e.included in e./yd3 i. Compaction unit cost included in e.included in e./yd3 j. Total on-site topsoil unit cost (e + h + i) $5.00 /yd3 k. Total off-site topsoil unit cost (f + g + h + i)$25.00 /yd3 l. Total on-site topsoil cost [j x (1-d) x c]$0 m. Total off-site topsoil cost (c x d x k)$1,131,350 n. Percent compaction 10%10% o. Total topsoil cost (l + m) * (1 + n)$1,244,485.00 III. Drainage Layer a. Area to be capped 56.1 acres x 4840 yd2/acre = 271,524 yd2 b. Depth of sand or gravel needed 0 inches x 1yd/ 36 inches = 0.00 yd c. Quantity of sand or gravel needed (a x b)0 yd3 d. Purchase unit cost $6.90 $6.90 /yd3 e. Delivery cost (for off-site material)$7.85/yd3 for 10 mil RT $7.85 /yd3 f. Spreading unit cost $1.39 $1.39 /yd3 g. Compaction unit cost $0.12 $0.12 /yd3 h. Percent compaction sand = 10%, gravel = 5%10 % i. Total drainage layer unit cost (d + e + f + g)$16.26 /yd3 j. Total drainage layer cost [c x i x (1+h)]$0.00 IV.On-Site Clay a. Area to be capped 56.1 acres x 4840 yd2/acre = 271,524 yd2 b. Depth of clay needed 0 inches x 1 yd/ 36 inches = 0.00 yd c. Quantity of clay needed (a x b)0 yd3 d. Excavation unit cost $2.50 $2.50 /yd3 e. Placement/Spreading unit cost $1.25 $1.25 /yd3 f. Compaction unit cost $0.85 $0.85 /yd3 g. Total on-site clay unit cost (d + e + f + g)$4.60 /yd3 h. Percent compaction 25%25 % i. Total on-site clay cost [c x g x (1 + h)]$0.00 V. Off-Site Clay a. Area to be capped (1acre=4840yd²)acres x 4840 yd2/acre = 0 yd2 b. Depth of clay needed (6" = 0.16 yd)inches x 1yd/ 36 inches = 0.00 yd Facility Name: L.V. Sutton Energy Complex, Onsite CCR Landfill Date: 11/23/15 Phase 1 (Cells 3-8)Calculated By: VMD Permit No.: Checked By: JC 1300 South Mint Street, Suite 410 Facility Address: Sutton Steam Plant Road Charlotte, North Carolina 28203 Wilmington, North Carolina Revision No.: 0 phone - 704.227.0861 Facility Owner: Duke Energy Progress, LLC Project No.: GC5770 Phase No.: 02 www.geosyntec.com c. Quantity of clay needed (a x b)(a x b)0 yd3 d. Purchase unit cost $5.35 $5.35 /yd3 e. Delivery cost (for off-site material)$7.85/yd3 for 10 mil RT $7.85 /yd3 f. Spreading unit cost $1.39 $1.39 /yd3 g. Compaction unit cost $0.82 $0.82 /yd3 h. Total off-site clay unit cost (d + e + f + g)$15.41 /yd3 i. Percent compaction 25%25 % j. Total on-site clay cost [c x h x (1 + i)]$0.00 VI. Drainage Pipe a. Length of pipe needed 4958.2 4958.2 LF b. Pipe unit cost $4.22 $4.22 /LF c. Trenching and backfilling cost $0.99 $0.99 /LF d. Total drainage pipe unit cost (b + c)$5.21 /LF e. Total drainage pipe cost (a x d)$25,832.22 VII. Synthetic Membrane a. Area to be capped with 60-mil HDPE 56.1 acres x 43560 ft2/acre = 2,443,716 ft2 b. Purchase unit cost $0.65 $0.65 /ft2 c. Taxes unit cost $0.03 $0.03 /ft2 d. Installation unit cost $0.16 $0.16 /ft2 e. Total synthetic membrane unit cost (b + c + d)$0.84 /ft2 f. Total synthetic membrane cost (a x e)$2,052,721.44 VIII. Geotextile Filter Fabric a. Quantity of filter fabric needed 0.0 acres x 43560 ft2/acre = 0 ft2 b. Purchase unit cost $0.25 $0.25 /ft2 c. Taxes unit cost $0.00 $0.00 /ft2 d. Installation unit cost $0.00 $0.00 /ft2 e. Total synthetic membrane unit cost (b + c + d)$0.25 /ft2 f. Total geotextile filter fabric cost (a x e)$0.00 VIII-a. Geonet Composite Notes & Guidance Values a. Quantity of Geonet Composite needed 56.1 acres x 43560 ft2/acre = 2,443,716 ft2 b. Purchase unit cost $0.64 $0.64 /ft2 c. Taxes unit cost $0.03 $0.03 /ft2 d. Installation unit cost $0.16 $0.16 /ft2 e. Total geonet composite unit cost (b + c + d)$0.83 /ft2 f. Total geonet composite cost (a x e)$2,028,284.28 VIII-b. Geosynthetic Clay Liner a. Quantity of GCL needed 0.0 acres x 43560 ft2/acre = 0 ft2 b. Purchase unit cost $0.48 $0.48 /ft2 c. Taxes unit cost $0.03 $0.03 /ft2 d. Installation unit cost $0.15 $0.15 /ft2 e. Total GCL unit cost (b + c + d)$0.66 /ft2 f. Total GCL cost (a x e)$0.00 IX. Soil Admixture a. Area to be capped 56.1 acres x 4840 yd2/acre = 271,524 yd2 b. Soil admixture unit cost $2.57 $2.57 /yd2 c. Total soil admixture cost (a x b)$697,816.68 Facility Name: L.V. Sutton Energy Complex, Onsite CCR Landfill Date: 11/23/15 Phase 1 (Cells 3-8)Calculated By: VMD Permit No.: Checked By: JC 1300 South Mint Street, Suite 410 Facility Address: Sutton Steam Plant Road Charlotte, North Carolina 28203 Wilmington, North Carolina Revision No.: 0 phone - 704.227.0861 Facility Owner: Duke Energy Progress, LLC Project No.: GC5770 Phase No.: 02 www.geosyntec.com X. Protective Soil Cover / Vegetative Cover a. Area to be capped 56.1 acres x 4840 yd2/acre = 271,524 yd2 b. Depth of soil needed 24 inches x 1yd/ 36 inches = 0.67 yd c. Quantity of soil needed (a x b)181,016 yd3 d. Percentage of soil from off-site 100%100% e. Excavation unit cost (on-site material)$5.00 $5.00 /yd3 f. Purchase unit cost (off-site material)$13.00 $13.00 /yd3 g. Delivery Cost (off-site material)$12.00/yd3 for 5 mil RT $8.00 /yd3 h. Placement/Spreading unit cost included in e.included in e./yd3 i. Compaction unit cost included in e.included in e./yd3 j. Total on-site soil unit cost (e + h + i) $5.00 /yd3 k. Total off-site soil unit cost (f + g + h + i)$21.00 /yd3 l. Total on-site soil cost [j x (1-d) x c]$0 m. Total off-site soil cost (c x d x k)$3,801,336 n. Percent compaction 10%10% o. Total protective soil cover cost (l + m) * (1 + n)$4,181,469.60 XI. Soil Testing / Construction Quality Assurance a. Number of acres to be capped 56.1 56.1 acres b. Testing unit cost (Includes density & permeability tests and technician)$10,000.00 $10,000.00 /acre c.Total Soil Testing Unit Cost (a x b)$561,000.00 XII. Vegetative Cover a. Number of acres to be vegetated 56.1 56.1 acres b. Unit cost for preparation, seeding, and fertilization $1,500.00 $1,500.00 /acre c.Total Vegetative Cover Cost (a x b)$84,150.00 XIII. Landfill Gas (LFG) Management System a. Number of acres of landfill to be closed 56.1 56.1 acres b. Number of LFG detection probes to be installed 0 0 probes c. Average number of LFG vents required per acre 0 0/acre d. Length of LFG detection probe in linear feet 0 100 LF e. Average cost per LFG vent $5,000.00 $5,000 /event f. LFG detection probe unit cost $40.00 $40.00 /LF g. Total cost for LFG vents (a x c x e)$0 h. Total cost for LFG detection probes (b x d x f)$0 i. Total gas management cost (g + h)$0.00 XIV. Groundwater monitoring system a. Hydrogeologic study $10,000 or as needed $0 b. Monitoring well construction/well $1,225 per well $1,225.00 /well c. Number of wells to be installed 0 0wells d. Additional well length of 50'0 0LF e. Unit cost for additional well length over 50'$22.00 $22.00 /LF f. Total additional cost for well length over 50'(e x d)$0 g. Total monitoring well construction cost (b x c)$0 h. Total Groundwater monitoring system cost (a + e + f)$0.00 XV. Mobilization/demobilization a. Cost for mobilization/demobilization assumes 1 event $75,000.00 XVI. Survey and deed notation a. Cost for survey and deed notation assumes $2,500/acre $140,250.00 Facility Name: L.V. Sutton Energy Complex, Onsite CCR Landfill Date: 11/23/15 Phase 1 (Cells 3-8)Calculated By: VMD Permit No.: Checked By: JC 1300 South Mint Street, Suite 410 Facility Address: Sutton Steam Plant Road Charlotte, North Carolina 28203 Wilmington, North Carolina Revision No.: 0 phone - 704.227.0861 Facility Owner: Duke Energy Progress, LLC Project No.: GC5770 Phase No.: 02 www.geosyntec.com XVII. Closure Certification a. Closure certification costs $35,500 or as needed $35,000.00 XVIII. Miscellaneous Costs to Close a. Erosion Control $50,000 or as needed $50,000.00 b. Storm Water Control (diversion berms and drainage ditches)$50,000.00 c. Drainage Layer Piping $0.00 d. Anchor Trench $0.00 e. Tie-in Seams $0.00 f. Geosynthetic Boots $0.00 Total Construction Closure Costs Total Unadjusted Closure Costs $10,945,884 City Cost Index (CCI)96.4 Total Adjusted Closure Costs $10,551,832 CCI x (I..XIV) Closure Cost-Estimate Subtotal $10,902,082 (Total adj. closure costs +XV + XVI + XVII + XVIII) Contingency (10%)$1,090,208 Engineering Fees Permitting and Construction Documents $109,021 Total Closure Cost $12,101,311 (Phase 1) Total Area to be capped 56.1 acres Approximate closure cost per acre $215,710 /acre Notes: Guidance values attained from similar projects. Material Costs for Geosynthetics include Delivery. Facility Name: L.V. Sutton Energy Complex, Onsite CCR Landfill Date: 11/23/15 Phase 1 Calculated By: VMD Permit No.: Checked By: JC 1300 South Mint Street, Suite 410 Facility Address: Sutton Steam Plant Road Charlotte, North Carolina 28203 Wilmington, North Carolina Revision No.: 0 phone - 704.227.0861 Facility Owner: Duke Energy Progress, LLC Project No.: GC5770 Phase No.: 02 www.geosyntec.com POST-CLOSURE COSTS: I. Groundwater Monitoring Notes & Guidance Values a. Total number of monitoring wells 9 9 wells b. Number of sampling events per year 2 sampling events per year 2 events c. Monitoring and analysis costs per sample $1,750 $1,750 /sample d. Miscellaneous Engineering Fees $10,000 or as required $10,000 /year e. Total annual monitoring costs [(a x b x c) + d]$41,500 /year f. Post-closure period 30 30 years g. Total cost for post-closure period (e x f)$1,245,000.00 II. Landfill Gas Monitoring a. Frequency of testing (4 events per year) 0 events/year b. Cost of sampling per event $1,000.00 $1,000.00 /event c. Total LFG Monitoring unit cost per year (a x c)$0.00 /year d. Post-closure period 30 30 years e. Total cost for post-closure period (d x e)$0.00 III. Leachate Management a. Private disposal unit cost $0.00 $0.00 /gal b. POTW disposal unit cost $0.10 $0.10 /gal c. Direct discharge to a POTW unit cost $0.00 $0.00 /gal d.Amount of leachate generated 50,000 50,000 gal/yr e. Load/unload unit cost $150 $150.00 /truck f. Capacity of truck 5,500 5,500 gallons g. Number of trucks required per year (d ÷ f) 9 trucks/year h. Distance over 5 miles of hauling (one way) 10 10 miles i. Cost of hauling per mile $1.50 $1.50 /mile j. Total cost for loading / unloading and hauling [(e x g) + (h x i)]$1,378.64 /year k. Total annual cost for Private Disposal (a x d) $0.00 /year l. Total annual cost for POTW Disposal (delivered)[(b x d) + j]$6,378.64 /year m. Total annual cost for POTW Disposal (direct)(c x d)$0 /year n. Total leachate management cost (k or l or m)$6,378.64 /year o. Post-closure period 30 30 years p. Total cost for post-closure period (n x o)$191,359.09 IV. Routine Maintenance and Repairs a. Mowing frequency 2 2 visits/year b.Area to be maintained (acres) 56.1 56.1 acres c. Mowing unit cost per visit $80 $80 /acre/visit d. Total mowing cost per year (a x b x c)$8,976 /year e. Fertilizer unit cost $500 $500 /acre f. Total fertilizer cost per year (b x e)$28,050 /year g. Number of years to reseed (max 3 years) 3 3 years h.Area to reseed (acres) 18.70 18.70 acres i. Reseeding unit cost $1,786 $1,786 /acre j. Total reseeding cost (g x h x i) $100,195 k. Mobilization/demobilization cost per year $150 $150 /year l. Total maintenance and repairs cost per year (d + f + k)$37,176.00 /year m. Post-closure period 30 30 years n.Total cost for post-closure period [(m x l) +j]$1,215,475 V. Vector and Rodent Control a. Total vector and rodent control costs per year $2,000 or as required $2,000.00 /year b. Post-closure period 30 30 years c.Total cost for post-closure period (a x b)$60,000 Total Post-Closure Costs Total Unadjusted Post-Closure Costs $2,711,833.69 City Cost Index (CCI) 96.4 Total Adjusted Post-Closure Costs $2,614,207.68 CCI x (I..V) Contingency (10%) $261,420.77 Total Post-Closure Cost-Estimate (Phase 1)$2,875,628