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5.a 6 Appendix E - Decomissioning PlanWoolford Community Solar Garden Decommissioning Plan and Site Reclamation April 11, 2017 City of Scandia Ordinance No. 174 Section 4.33(3)(F): Decommissioning Plan. The applicant shall submit a decommissioning plan to ensure that facilities are properly removed after their useful life. If the solar energy system remains nonfunctional or inoperative for a continuous period of one year, the system shall be deemed to be abandoned and shall constitute a public nuisance. The plan shall include provisions for removal of all structures and foundations, restoration of soil and vegetation, and a plan ensuring financial resources will be available to fully decommission the site. The City may require the posting of a bond, letter of credit or the establishment of an escrow account to ensure decommissioning. Decommissioning and Reclamation Upon the expiration of the site permit, or the end of commercial operations, MSC will be responsible for removing solar facilities at the site to a depth of 36 inches and to restore and reclaim the site to pre -construction topography and topsoil quality to the extent feasible. MSC reserves the right to extend the Project instead of decommissioning at the end of the Site Permit term (or sooner) by applying for an extension of the Site Permit. If MSC seeks to extend the life of the Project, MSC will decide whether to continue operation with existing equipment or to retrofit solar panels and power system with upgrades based on new technologies. Decommissioning includes removing the solar panels, solar panel racking, steel foundation posts and beams, inverters, transformers, overhead and underground cables and lines, equipment pads and foundations, equipment cabinets, and ancillary equipment to a depth of 36 inches. The civil facilities, access road, security fence, and any drainage structures are included in the scope. Standard decommissioning practices would be utilized, including dismantling and repurposing, salvaging/recycling, or disposing of the solar energy improvements. After all equipment is removed, any holes or voids created by poles, concrete pads and other equipment will be filled in with soil to the surrounding grade and seeded with a previously approved seed mix. All access roads and other areas compacted by equipment will be decompacted to a depth of 18 inches from finished grade prior to fine grading and seeding. This may include re -vegetation as native prairie, returning the site to agricultural use consistent with MSG's Agricultural Impact Mitigation Plan, or re -development of the land for other beneficial uses. Decommissioning and Site Reclamation Plan Narrative Page 2 of 6 List of Decommissioning Activities Timeline Decommissioning is estimated to take three to four weeks to complete and the decommissioning crew will ensure that all equipment and materials are recycled or disposed of properly. Removal and Disposal of Site Components The removal and disposal details of the site components are found below. Modules: Modules will be inspected for physical damage, tested for functionality, and disconnected and removed from racking. Functioning modules will be packed and stored in an offsite facility for reuse or resale by MSC. Non-functioning modules will be packed, palletized and shipped to the manufacturer or a third party for recycling. Racking: Racking and racking components will be disassembled and removed from the steel foundation posts, sorted, processed to appropriate size, and sent to a metal recycling facility. Steel Foundation Posts: All structural foundation steel posts will be pulled out to full depth, removed, processed to appropriate size, and shipped to a recycling facility. During decommissioning the area around the foundation posts may be compacted by equipment and, if compacted, the area will be de -compacted in a manner to adequately restore the topsoil and sub -grade material to a density consistent with native prairie or agricultural uses. Overhead and Underground Cables and Lines: The cables and conduits contain no materials known to be harmful to the environment. As part of the decommissioning of the project, these items will be removed up to a depth of 36 inches and shipped to a recycling facility. Topsoil will be segregated and stockpiled for later use prior to any excavation and the subsurface soils will be staged next to the excavation. Following the removal of the cable and conduits the excavation will be back-filled with the spoils previously removed. The subgrade will be compacted to a density similar to native prairie or agricultural uses. Topsoil will be redistributed across the disturbed area. All cable and conduit buried deeper than 36 inches will be left in place and abandoned. Inverters, Transformers, and Ancillary Equipment: All electrical equipment will be disconnected and disassembled. All parts will removed from the site and reconditioned and reused, sold as scrap, recycled, or disposed of appropriately, at MSC's sole discretion, consistent with applicable regulations and industry standards. Decommissioning and Site Reclamation Plan Narrative Page 3 of 6 Equipment Pads and Ancillary Foundations: Topsoil will be removed from an area surrounding the foundation and stockpiled for later use/replacement, as applicable. Foundations will be excavated to a depth sufficient to remove all conduits, cables, aggregate and concrete to a depth of 48 inches below grade. The remaining excavation will be filled with clean subgrade materials of quality comparable to the immediate surrounding area. All unexcavated areas compacted by equipment used in decommissioning will be de - compacted in a manner to adequately restore the topsoil and sub -grade material to a density consistent and compatible with native prairie or agricultural uses. All materials will be removed from the site and reconditioned and reused, sold as scrap, recycled, or disposed of appropriately, at MSC's sole discretion, consistent with applicable regulations and industry standards. Fence: All fence parts and foundations will be removed from the site and reconditioned and reused, sold as scrap, recycled, or disposed of appropriately, at MSC's sole discretion, consistent with applicable regulations and industry standards. The surrounding areas will be restored to pre -construction conditions to extent feasible. Computers, monitors, hard drives, and other components: All parts will removed from the site and reconditioned and reused, sold as scrap, recycled, or disposed of appropriately, at MSC's sole discretion, consistent with applicable regulations and industry standards. Access Roads: Facility access roads will be used for decommissioning purposes, after which removal of roads will be discussed with the Landowner, using the following process: 1) After final clean-up, roads may be left intact through mutual agreement of the Landowner and MSC unless otherwise restricted by Federal State or Local Regulations. 2) If a road is to be removed aggregate will be removed and shipped from the site to be reused, sold, or disposed of appropriately, at MSC's sole discretion, consistent with applicable regulations and industry standards. Ditch crossings connecting access roads to public roads will be removed unless the landowner requests they remain. The subgrade will be de -compacted to a density similar to surrounding sub -grade material. Topsoil will be distributed across the open area. The access roads and adjacent areas that are compacted by equipment will be de -compacted in a manner to adequately restore the topsoil and sub -grade material to a density consistent with native prairie or agricultural uses. Land Leveling: As part of site decommissioning, to the extent commercially reasonable, MSC will restore the area disturbed by construction to pre -construction elevation and contour to extent feasible. If uneven settling occurs or surface drainage problems develop, as a result of Project decommissioning, MSC will provide additional land leveling services, or compensation, within 45 days of receiving a Landowner's written notice, weather permitting. Decommissioning and Site Reclamation Plan Narrative Page 4 of 6 Restoration/Reclamation of Site MSC will restore and reclaim the site based upon the property use intended by the landowner after decommissioning. MSC assumes that most site will be utilized for agriculture after decommissioning and will implement appropriate measures to facilitate agricultural use. If no specific use is identified, MSC will vegetate the site with a native prairie seed mix. The goal of restoration will be to restore natural hydrology and plant communities to the greatest extent practicable while minimizing new disturbance and removal of native vegetation. The decommissioning best management practices (BMP's) to minimize erosion and contain sediment that will be employed on the Project to the extent practicable with the intent of meeting this goal include: 1. Minimize new disturbance and removal of native vegetation to the greatest extent practicable. 2. Removal of solar equipment and access roads up to three (3) feet below surrounding grade, backfill with subgrade material and cover with suitable topsoil to allow adequate root penetration for native plants, and so that subsurface structures do not substantially disrupt ground water movements. 3. Any topsoil that is removed from the surface for decommissioning will be stockpiled to be reused when restoring plant communities. Once decommissioning activity is complete, topsoil will be restored to assist in establishing and maintaining plant communities. 4. Stabilize soils and re -vegetate with native prairie plants appropriate for the soil conditions and adjacent habitat and use local seed sources where feasible, consistent with landowner objectives. Reseeding with native plants will not be performed for site that will be returned to agricultural use or other more intensive beneficial uses. 5. During and after decommissioning activities, install erosion and sediment control measures in all disturbance areas where potential for erosion and sediment transport exists, consistent with storm water management objectives and requirements. 6. Remediate any petroleum product leaks and chemical releases prior to completion of decommissioning. Decommissioning and restoration activities at each site will be completed within 12 months after the date the site ceases to operate. Post -Restoration Monitoring Decommissioning of the site will not require new permits or approvals except a NPDES/SDS CSW Permit and SWPPP, if grading activities are necessary and exceed applicable permit thresholds. Decommissioning should include post -restoration monitoring as required by the NPDES/SDS CSW Permit and SWPPP or other applicable requirements. In addition, the MSC Field Representative assigned to decommissioning monitoring will stay in contact with landowners, including onsite check -ins until the NPDES/ SDS CSW permit is closed. In situations where additional restoration is necessary, the compliant procedure will be followed to determine the need for additional restoration (Fertilizing or reseeding). Decommissioning and Site Reclamation Plan Narrative Page 5 of 6 As part of the post restoration monitoring, the MSC Field Representative will also survey for excessive noxious weeds and address if this is an issue. This may involve consulting an agronomist or biologist if revegetation is not sufficient or if there are problems with noxious weeds during the first growing season, or until MSC no longer has control over the land. Decommissionin,a Costs MSC will be responsible for all costs to decommission the project and associated facilities. Decommissioning cost is expected to be approximately $142,348. Based on current scrap material prices, the estimated salvage value of the decommissioned components is anticipated to equal approximately $77,293. Therefore the resulting decommissioning costs less the salvage value is $65,055. Since no solar photovoltaic projects have been decommissioned to date, the costs are based on estimated time, equipment, disposal costs, and recycling prices. A detailed breakdown of this updated cost estimate is attached as Exhibit A. Decommissioning Financial Resource Plan To ensure MSC can adequately fund the obligations of this plan, MSC will enter into either a mutually acceptable agreement (the "Escrow Agreement") establishing an escrow (the "Escrow") to secure MSC obligations for decommissioning or will offer a "Letter of Credit" or equivalent form of security to the Landowner. The mutually agreed upon form of security will be established in Year 10 of the Project's operational life in an amount equal to the total decommissioning cost, less the estimate salvage value of the materials. Providing flexibility in the form of the escrow or security allows MSC to evaluate the cost of obtaining the security at the time of issuance in Year 10 and to move forward with the most cost effective solution for the project given market conditions. The exact amount to be allocated for decommissioning will be determined by a 3rd party and updated every 10 years after Year 10 to reassess the difference between the estimated commissioning costs and salvage value. MSC believes that reassessing the decommissioning and salvage values every 10 years is prudent as technology, costs and market conditions may change. The escrow or security shall be held, administered, and disbursed by a title company, bank or other qualified escrow agent mutually satisfactory to MSC and the applicable landowner. If MSC does not remove the solar facilities within twelve (12) months after the expiration of the lease or earlier termination of the lease, the landowner may draw from the Escrow or security an amount sufficient to reimburse Landowner for the difference between lessor's out-of-pocket costs of removing the solar facilities, less the salvage value of the solar facilities. Estimated Decommissioning Costs Westwood Including Dismantling/Revmoval Costs and Salvage Value Project Name: Woolford Community Solar, LLC Date: April 5, 2017 By: JTW Project Size 1 MW -AC Quantity Unit Unit Cost Total Cost Cost Per MW Mobilization/Demobilization 1 Lump Sum $20,000.00 $20,000 $20,000 Permitting State Permits 1 Lump Sum $5,000.00 $5,000 N/A Subtotal Permitting $5,000 Civil Infastructure Based on road quantities shown on plans Removal Gravel Surfacing from Road 52 Cubic Yards $4.00 $208 $208 based on 2802Ft of Road x 0.50' gravel surface thickness Haul Gravel Removed from Road 52 Cubic Yards $6.00 $311 $311 based on 2802Ft of Road x 0.50' gravel surface thickness Disposal of Gravel Removald from Road 52 Cubic Yards $10.00 $519 $519 based on 2802Ft of Road x 0.50' gravel surface thickness Removal Geotextile Fabric from Road Area 0 Square Feet $0.10 $0 $0 based on 2802 Sq Ft of Road Removal Culvert from Beneath Road 0 Each $1,200.00 $0 $0 Based on plan drainage schedule (other culverts in facility plans) Haul Culvert Removed from Road 0 Each $100.00 $0 $0 Based on plan drainage schedule (other culverts in facility plans) Disposal of Culverts 0 Each $0.00 $0 $0 Based on plan drainage schedule (other culverts in facility plans) Removal Low Water Crossing from Road 0 Each $3,400.00 $0 $0 Based on plan drainage schedule Haul Low Water Crossing Materials Removed from Road 0 Each $1,800.00 $0 $0 Based on plan drainage schedule Disposal of Low Water Crossing Materials 0 Each $500.00 $0 $0 Based on plan drainage schedule Grade Road Corridor 2,802 Square Feet $0.25 $701 $701 based on 2802 Sq Ft of Road Erosion and Sediment Control Along Road 150 Linear Feet $2.00 $300 $300 Based on road quantities shown on plans Topsoil and Turf Establishment on Removed Road Area 0.1 Acres $11,000.00 $1,061 $1,061 Based on road larea x 1.5 to allow for work area Removal of Security Fence 2,418 Linear Feet $6.00 $14,508 $14,508 Subtotal Civil Infastructure $17,608 Structural Infastructure Based on post quantities provided on plans Removal Tracker Array Steel Foundation Post Full Depth 648 Each $13.00 $8,424 $8,424 Based on post quantities provided on plans Haul Tracker Array Steel Post 58 Ton $6.75 $394 $394 Based on $0.15 per ton -mile and 45 mile round trip, average post length 15', p Removal PCU Station Post to a 4' Depth 8 Each $65.00 $520 $520 Based on post quantities provided on plans Haul PCU Station Post 8 Each $3.00 $24 $24 Based on post quantities provided on plans Removal Array Racking 78 Ton $200.00 $15,680 $15,680 Based on square feet of rack size times 1 pound per Sq Ft Haul Array Racking 78 Ton $6.75 $529 $529 Based on $0.15 per ton -mile and 45 mile round trip, average post length 15', p Subtotal Structural Infastructure $25,571 Westwood Electrical Collection/Transmission System Removal of PV Moduals Removal of String Inverters Removal of Panelboards Removal of PCU Station (Inverter/Transformer) Removal of Riser Pole and Overhead Cable Removal of SCADA Equipment Removal of Underground Collector System Cables Removal of Fiber Optic Cable Subtotal Electrical Collection/Transmission System Site Restoration Stabilzied Construction Entrance Perimeter Controls Topsoil and Turf Establishment on area within Removed Array Subtotal Site Restoration Subtotal Demolition/Removals Salvage Fencing Steel Posts Module Racking PV Modules String Inverters Transformer Scada Equipment Collection Lines Subtotal Slavage Total Demolition Minus Salvage Estimated Decommissioning Costs Including Dismantling/Revmoval Costs and Salvage Value 4,320 Each $10.00 $43,200 $43,200 Based on 72 modules per rack (Pricing based on production rate of disconnecti 20.0 Each $60.00 $1,200 $1,200 Quanitites Provided on Plan 4.0 Each $40.00 $160 $160 Quanitites Provided on Plan 1.0 Each $2,000.00 $2,000 $2,000 Quanitites Provided on Plan, Includes Equipment Pad 1.0 Each $1,000.00 $1,000 $1,000 Quanitites Provided on Plan 1.0 Each $1,000.00 $1,000 $1,000 Quanitites Provided on Plan 2,140.0 Linear Feet $5.00 $10,700 $10,700 Quanitites Provided on Plan 1.0 Per MW $500.00 $500 $500 Quanitites Provided on Plan $59,760 1.0 Each $1,700.00 $1,700 $1,700 Quanitites Provided on Plan 1,209 Linear Feet $2.00 $2,418 $2,418 Quanitites Provided on Plan 7.9 Acres $1,300.00 $10,292 $10,292 Quanitites Provided on Plan $14,410 $142,348 2,418 Linear Feet $0.00 $0 $0 58 Tons $240.00 $13,997 $13,997 78 Tons $240.00 $18,816 $18,816 4,320 Each $10.00 $43,200 $43,200 20 Each $3.69 $74 $74 1 Each $123.69 $124 $124 1 Each $0.00 $0 $0 4,708 Pounds $0.23 $1,083 $1,083 Notes: 1. Prices used in analysis are estimated based on research of current average costs and salvage values. 2. Prices provided are estimates and may fluctuate over the life of the project. 3. Contractor means and methods may vary and price will be affected by these. $77,293 $65,055 Subtotal Demolition/Removals per MW $142,348.41 Included in the unit price for Removal of Security Fence Assumed (12 Ib/ft with approximately 15 feet of salvageable post), HMS #1 prig Based on HMS #2 price $240/ton Based on recent solar decommissioning plans Based on 123 pounds per inverter, Metro Metals Recycling Quote for transfom Based on 4123 pounds per transfomer, Metro Metals Recycling Quote for trans Price Based on mixed Aluminum EC Scrap 2.2 pounds per foot, Metro Metals R Subtotal Salvage Per MW $77,293.13 Total Demolition Minus Salvage Per MW $65,055.28 Westwood March 29, 2017 Solar Farm Decommissioning Assumptions To develop a cost estimate for the decommissioning of the Community Solar Garden, Westwood engineers made the following assumptions and used the following pricing references. Costs are estimated based on current pricing, technology, and regulatory requirements. The assumptions are listed in order from top to bottom of the estimate spreadsheet. When publicly available bid prices, or MnDOT bid summaries were not available for particular work items, we developed time and material based estimates, considering composition of work crews and equipment and material required. When materials may have a salvage value at the end of the project life the construction activity costs and from the hauling/freight cost are separated from the disposal costs or salvage value to make revisions to salvage values more transparent. 1. Decommissioning year is based on the 25 year projected life of the project. 2. A project of this size and complexity does not require a full time project manager or support staff. It can be managed by a field supervisor. 3. Common labor will be used for the majority of task except for heavy equipment operation. Since MNDOT unit prices are used where possible the labor rates will reflect union labor rates. 4. Mobilization was estimated at approximately 8% of total cost of other items. 5. Permit applications will require the preparation of a Storm Water Pollution Protection Plan (SWPPP) and a Spill Prevention Control and Countermeasure (SPCC) Plan. 6. Road gravel removal matches the MnDOT item Subgrade Excavation. Since the material will not remain on site a hauling cost is added to the MnDOT cost. The recycling costs for road aggregate are volatile varying from approximately $10 per ton for disposal to $10 per ton for recycling. 7. A cost for removal of geotextile under the road has been added to be conservative, as use of geotextile is an option, but may not be used. 8. Low water crossings are composed primarily of aggregate without salvage value because of mixing with other soils. Pricing used is higher than MnDOT unit prices for Channel excavation to reflect equipment mobilization costs spread over a small volume of material, sediment and runoff control, and the replacement materials required to restore the area. 9. Grade Road Corridor reflects the cost of mobilizing and operating light equipment to spread and smooth the topsoil imported to replace the aggregate removed from the road.. 10. Erosion and sediment control along road reflects the cost of silt fence on the downhill side of the road. 11. Topsoil cost for 360 cu yds is approximately $9500 for topsoil required is to replace the road aggregate. Subsoiling cost to decompact roadway areas is $500 per acre, and Turf Establishment, which includes seed, fertilizer, mulch and care until grass is established is $1000 per acre. 12. The MnDOT pay item, remove Chain Link Fence includes disposal of the material which has a salvage value. Westwood March 29, 2017 13. Tracker array posts are lightweight "I" beam sections installed with a backhoe like piece of specialized equipment. Crew productivity is approximately 150 posts per day, and the same crew and equipment should have a similar productivity removing the posts, resulting in a per post cost of approximately $13.00. 14. Several steel recycling facilities are located near Minneapolis, the posts weigh approximately 200 pounds each, and we estimate the hauling costs at approximately $0.15 per ton mile. 15. Based on the review of a manufacturer's details of the array support structures the structure weigh approximately one pound per square foot. Each solar panel has an area of four square feet. The facility has approximately 54,540 modules, 218,160 square feet of array, 110 tons. The frames are made of light weight steel extrusions so a crew with hand tools can disassemble and cut the pieces to sizes for recycling at a rate of about 400 pounds per person per hour, or about $200 per ton. 16. Hauling the steel to Minneapolis at $0.15 per ton mile costs about $30 per ton. 17. The solar panels for this project measure approximately two feet by four feet and weigh 26 pounds so they can easily be disconnected, removed, and packed by a two person crew at a rate we estimate at 20 panels per hour. 18. Combiner boxes and junction boxes are relatively small enclosures (similar in size to household circuit breaker panels) that are pole mounted and can be disconnected and lifted by a single person. 19. Inverter/transformers for this size project are pad mounted. The transformers weigh approximately 4000 pounds and contain either copper, or more commonly aluminum windings that have significant salvage value. The estimated costs include removal of the concrete pads and conduits feeding the equipment. 20. Medium voltage (MV) equipment and SCADA equipment are mounted on the same concrete pads and enclosed in weather proof cabinets. Their size requires light equipment to remove them. The costs shown include the removal of the concrete pads. 21. The underground collector system cables are placed in trenches about four feet deep. Several cables/circuits are placed side by side in each trench. Removal of the cables does not require trenching for the entire length as the cables are strong enough to be pulled out of the ground with a small bulldozer or other equipment. 22. To reduce tracking of sediment off site by trucks removing materials we have included a rock construction entrance priced based on MnDOT data. 23. Perimeter control pricing is based on silt fence placed on the project perimeter and protecting wetlands and drainage swales within the project area. Pricing is based on MnDOT unit prices. 24. No topsoil was planned to be removed from the site during construction and most of the site will not have been compacted by heavy truck or equipment traffic so the site Turf Establishment cost is based on MnDOT unit prices of $1000 per acre plus an allowance for some areas to be decompacted. Westwood March 29, 2017 25. Metal salvage prices (steel, aluminum, copper) are based on quotes from www.scrapmonster .com for the U.S. Mid -West. These prices are based on delivery to the recycling facility with the material prepared to meet size, thickness, cleanliness and other specifications. 26. The salvage value for fencing is already reflected in the MnDOT unit price, so no credit is taken under salvage value. 27. The steel posts and array racking are priced based on #1 HMS (high melt steel). 28. Modules degradation is approximately 0.50% per year, or 88% after25 years. There is currently a robust market for used solar panels and pricing can be found on ebay and other sites. We have assumed that as long as the modules are producing power they will have economic value. To avoid unconservative pricing for the used modules we used the minimum pricing of $0.04 per watt found in the published paper, "Salvage Value of Photovoltaic Systems" 29. There is an active market for reselling and recycling electrical transformers and inverters with several national companies specializing. We have assumed that the electrical equipment will be obsolete at the time of decommissioning so we have based the pricing on a percentage of the weight that reflects the aluminum windings that can be salvaged. 30. The collection lines are priced assuming aluminum conductor wire (e.c. aluminum wire) prices reduced to reflect the insulation and other materials that must be stripped from direct burial wire so that the aluminum can be recycled. 31. Care to prevent damage and breakage of equipment, PV modules, inverters, capacitors, and SCADA will be exercised but removal will be by unskilled common labor under supervision. 32. All salvage will be for bulk material or equipment