Appendix D Decommissioning and Reclamationdeq.wyoming.gov/media/attachments/Industrial...

Appendix D Decommissioning and Reclamation

Appendix D.1 Decommissioning and Reclamation Plan

BOSWELL SPRINGS PROJECT Decommissioning and Reclamation Plan August 2017

BoswellWindLLC.2017.BoswellSpringsProjectDecommissioningandReclamationPlan.August.

Boswell Wind, LLC

Boswell Springs Project

Decommissioning and Reclamation Plan

i August 2017

Contents

Page

Chapter 1 Wind Facility Decommissioning ......................................................................................... 1‐1

1.1 Nature and Location of Facility ........................................................................................ 1‐1

1.2 Facility Decommissioning................................................................................................. 1‐1

Chapter 2 Reclamation ...................................................................................................................... 2‐1

2.1 Noxious Weed Control ..................................................................................................... 2‐1

2.2 Interim Reclamation ........................................................................................................ 2‐1

2.3 Final Reclamation ............................................................................................................. 2‐2

2.4 Reclamation Success ........................................................................................................ 2‐3

Chapter 3 Reclamation Seed Mixes ................................................................................................... 3‐1

3.1 Shallow Loamy Ecological Site Description ...................................................................... 3‐1

3.2 Loamy Ecological Site Description ................................................................................... 3‐2

3.3 Sandy Ecological Site Description .................................................................................... 3‐3

3.4 Shallow Sandy Ecological Site Description ....................................................................... 3‐3

3.5 Coarse Upland Ecological Site Description ...................................................................... 3‐4

Chapter 4 References ........................................................................................................................ 4‐1

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Tables

Table Page

Table 3‐1. Seed Mixes for Bluebunch Weatgrass/Rhizomatous Wheatgrass Plant

Community (Shallow Loamy ESD) .................................................................................... 3‐2

Table 3‐2. Seed Mixes for Rhizomatous Wheatgrass/Needle and Thread Plant Community

(Loamy ESD) ..................................................................................................................... 3‐2

Table 3‐3. Seed Mixes for Needle and Thread/Rhizomatous Wheatgrass Plant Community

(Sandy ESD) ...................................................................................................................... 3‐3

Table 3‐4. Seed Mixes for Mid Bunchgrass Plant Community (Shallow Sandy ESD) ........................ 3‐4

Table 3‐5. Seed Mixes for Mid Bunchgrass/Bitterbrush Plant Community (Coarse Upland

ESD) .................................................................................................................................. 3‐4

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Acronyms

BMPs best management practices

ESDs Ecological Site Descriptions

ISC Industrial Siting Council

MLRA Major Land Resource Area

NRCS Natural Resource Conservation Service

PLS lbs./ac Pure Live Seeds per acre

SWPPP Stormwater Pollution Prevention Plan

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1‐1 August 2017

Chapter 1 Wind Facility Decommissioning

ThissectionprovidesinformationonthemethodologyfordecommissioningtheProject.Asrequiredbyagenciesandlandowner,BoswellWindwillprovideassurancesthattheplanscanbeimplementedintheformofasuretybond,certificateofdeposit,corporateguaranteeorotherformacceptabletotheWDEQandtheIndustrialSitingCouncil(ISC)priortoconstruction.ThevalueofthesecuritywillreflectthegrossdecommissioningandreclamationcostsfortheProject.

Facilitydecommissioningandreclamationwillbeginwithin12monthsafterthefacilityoranindividualwindturbineceasestoproduceelectricity.TheCouncilmayextendthetimeperiodofSection(8)(a)(iii)(B)ifthefacilitydemonstratesgoodcausepriortotheendofthecontinuousperiodof(12)monthsofthefacilityorwindenergygeneratingtowersnotgeneratingelectricity.BoswellWindwillprovideupdatestotheAdministratoreveryfive(5)years.

1.1 Nature and Location of Facility TheproposedProjectislocatedinAlbanyCounty,10milesnorthofRockRiver,WY,and15mileseastofMedicineBow,WY,atelevationsrangingfrom6,713to7,192feet.ThemainaccesstotheProjectwillbeviaInterstate80(locatedabout50milessouthoftheProject),U.S.Highway30,andFettermanRoad,whichbisectstheProjectArea.Thesiteisrelativelyflatandischaracterizedbyrollingplainswithhills,cuestas,mesas,andterraces.Thesiteisdominatedbygrasslandwithpocketsofsagebrushinthenorthwesternandnortheasternportionsofthesite.ThereareafewriparianemergentwetlandsalongSevenmileCreekandSpringCreek,butnolargebodiesofopenwaterexistwithinthesite.TheProjectAreaislargelyundevelopedandmainlyusedforcattleranching.Stockhandlingareas,roadsandfences,andstockpondsandreservoirsaretheprimaryconstructedfeaturescurrentlyonsite.

1.2 Facility Decommissioning Decommissioningisastep‐by‐step,methodicaldeconstructionprocess,whichinvolvesremovinganddisposingoftheProject’sturbinesandassociatedfacilitiesandinfrastructure.Withsomeexceptions,sitedecommissioninginvolvesthereverseofsiteconstruction.DecommissioningoftheBoswellSpringsProjectisexpectedtofollowastandardprocedure,whichtypicallyincludesthefollowing:

Allturbineswillbedismantledandeitherrelocatedtootherwindenergyprojectsorsoldforscrapvalue;

Electronicequipmentwillberecycledwheneverpossible.Ifnot,itwillbedisposedofinlandfillsorproperlylicensedhazardouswastefacilitiesasappropriate(someelectronicsareconsideredhazardouswasteduetothepresenceofheavymetals);

Transformersandelectricalcontroldeviceswillbereusedinotherapplicationsorsoldasscrapafterfluidremoval;

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Turbinefoundationswillberemoveddowntoadepthoffourfeetandbackfilledwithstockpiledsubsoilandtopsoil;

Undergroundcollectorcableswillberemoved;

Accessroads,rockorgravelintheelectricalsubstations,transformerpads,andbuildingfoundationswillberemovedandrecycledifnolongerneededorwantedbythelandowners;

Landareascoveredinrock,gravel,orbuilding/towerfootprintswillberestoredtoanaturalgrade(whichincludesamelioratingsoilcompactionthatmighthaveresultedfromprojectuses)andreseededorreplantedwithnativevegetationorpasturegrassesfollowingconsultationwithcurrentlandowners;

Electricalsubstationsandstoragebuildingwillbedismantled,includinginspectionforandremediationofanyenvironmentalcontamination;

Demolitionorremovalofequipmentfacilitieswillmeetapplicableenvironmentalandhealthregulations,andeconomicallyrecoverablematerialswillbesalvaged;

Alldisturbedareaswillbereclaimedandrestoredsopriorlandusescanberesumed.

Withlandownerapproval,BoswellWindmayleavethemaintenancebuildingonsite.ThiswouldalsorequirewrittennotificationtotheAdministrator.

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2‐1 August 2017

Chapter 2 Reclamation

Followingdecommissioning,interimreclamationwillincluderevegetationoftemporarysurfacedisturbancewithseedmixesagreeduponwiththelandowner.

Afterdecommissioningthedisturbedareaswillbereclaimedandreturnedtopre‐Projectlanduses(grazing).Asrequiredbylandowneruseagreement,finalreclamationwillincluderegradingorre‐contouring,soilamendments,andreseedingdisturbedareaswithagreeduponseedmixes,andcontrollingnoxiousweeds.RefertoChapter3,EcologicalSiteDescriptions,forthepreferredseedmixesforbothinterimandfinalreclamationdependingonthevariousecologicalsiteconditionsthroughouttheProjectArea.

2.1 Noxious Weed Control BoswellWindwillcontrolnoxious,non‐native,andinvasiveweedsintheProjectArea.Asappropriate,BoswellWindwillimplementthefollowingbestmanagementpractices(BMPs):

Onlyapproved,certifiedweed‐freeseedswillbeused.

MonitoringthroughouttheProjectAreafornoxiousandinvasiveweedswilloccurregularly.

Weedswillbecontrolledasneededandwithappropriatecontrolmethods.

Contractorswillwashconstructionequipmenttoensurethatitisfreetopotentialweedseeds.

Weedoccurrenceswillbemarkedduringdecommissioning.

2.2 Interim Reclamation InterimreclamationwillcomplywithapplicablepermittingrequirementsoftheDEQWaterQualityDivisionstormwaterprogram.Oncevegetationiscleared,BoswellWindwillsalvagesoilduringconstructionactivitieswhichwillberemovedascut,usedasfill,orstockpiledforfutureinterimoffinalreclamation.Followingdecommissioning,temporaryworkareas(e.g.,parkingandlaydownareas,accessroadshoulders,cabletrenches,etc.)willbereclaimedandrevegetatedwithlandowner‐approved,habitat‐appropriateseedmixesincludedinthisplan.Temporaryworkareaswillbepreparedforseedingbyusingmethodsincludingbynotlimitedtosoilconditioning,decompaction,andtopsoilprotectionmeasurestoreestablishtopsoilpropertiesandtoprotecttheseedingsurface.Seedbedpreparationmayincludetopsoilreplacement,discing,mulching,hydro‐seeding,targetedfertilization,watering,andothersurfacerougheningtechniquesasappropriatewhichwillhelpensuresuccessfulestablishmentofvegetation.Initialseedingwillbeusedtoachievetemporaryvegetationcoverageorstabilizationofsoilstockpilesuntilinterimreclamationmeasurescanbeimplemented.

RecommendedseedmixesbasedonEcologicalSitespresentwithintheProjectAreaareprovidedbelowinChapter3.ReclamationSeedMixes.Seedmixeswillbedevelopedincoordinationwithlandownersandwillbetailoredtoestablishspeciescomposition,structure,andtotalgroundcover

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appropriateforthedesiredplantcommunity.Seedingwillbeimplementedduringallphasesofdevelopmentdependingoninterimorfinalreclamationobjectives.Whenpossible,seedingwilloccurpriortoprecipitationeventstoincreasethelikelihoodofgerminationandvegetationestablishment.SeedingofaffectedlandwillbeconductedduringthefirstnormalperiodforfavorableplantingconditionsafterfinalpreparationunlessanalternativeplanisapprovedbyISC.

BoswellWindwillcontrolnoxious,non‐native,andinvasiveweedsintheProjectAreaincooperationwithlandowners.Areasmostsusceptibletonoxiousandinvasiveweedinfestations(e.g.,disturbedsoils,roadsides,drainages)willbemonitoredregularlyforthepresenceofnoxiousandinvasiveweeds.

2.3 Final Reclamation

2.3.1 Existing Site Conditions

TheProjectsiteislocatedinAlbanyCounty,10milesnorthofRockRiver,WY,and15mileseastofMedicineBow,WY,atelevationsrangingfrom6,713to7,192feet.Thesiteisrelativelyflatandischaracterizedbyrollingplainswithhills,cuestas,mesas,andterraces.Thesiteisdominatedbygrasslandwithpocketsofsagebrushinthenorthwesternandnortheasternportionsofthesite.ThereareafewriparianemergentwetlandsalongSevenmileCreekandSpringCreek,butnolargebodiesofopenwaterexistwithinthesite.TheProjectsiteislargelyundevelopedandmainlyusedforcattleranching.

VegetationcoveristypicaloftheLaramieBasinandFoothillShrublandsandLowMountainsecoregions,whichisdominatedbysagebrushsteppeandmixed‐grassprairie.TheFoothillShrublandischaracterizedbymontaneshrublandconsistingofmountainbigsagebrush(Artemisiatridentata),rabbitbrush(Chrysothamnusspp.),bluebunchwheatgrass(Pseudoroegneriaspicata)andIdahofescue(Festucaidahoensis)atlowerelevationsandbyRockyMountainjuniper(Juniperusscopulorum)andponderosapine(Pinusponderosa)athigherelevations.Utahjuniper(Juniperusosteosperma)andmountainmahogany(Cercocarpusledifolius)woodlandsoccuronrockoutcrops.TheLaramieBasinisdominatedbybluegrama(Boutelouagracilis),Indianricegrass(Achnatherumhymenoides),westernwheatgrass(Pascopyrumsmithii),rabbitbrush,fringedsage(Artemisiafrigida),andavarietyofotherforbandshrubspecies.

2.3.2 Reclamation Methods

Afterturbinedecommissioningandremoval,thedisturbedareaswillbereclaimedandreturnedtopre‐Projectlanduses(grazing)andwillfollowlandowneruseagreements.Disturbedareaswillbefilledinwithnativesoilandcompacted.Thesurfacewillbegradedandre‐contouredtoblendinwithexistingtopographyandsurroundingterrain.Majordisturbancefromdecommissioningactivitieswillberepairedandroadswillbeleftinplaceforlandowneruse.Thesubstationareawillbefilledinwithnativesoilandwillbegradedandreturnedtonaturalcontours.

Themethodsoffinalreclamationwillfollowmethodsdiscussedaboveforinterimreclamationincludingsoilandseedbedpreparation,seeding,andinvasiveweedcontrol.

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2‐3 August 2017

2.4 Reclamation Success Reclamationwillbeimplemented,managed,androutinelymonitoredbyBoswellWindwithoversight/approvalfromISC.SuccessstandardswilltiertothosesuccessstandardsidentifiedintheStormwaterPollutionPreventionPlan(SWPPP)thatwillbedevelopedfortheWyomingPollutantDischargeEliminationSystem–LargeConstructionPermit.

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3‐1 August 2017

Chapter 3 Reclamation Seed Mixes

ThedominantvegetationhabitattypesarederivedfromNaturalResourceConservationService(NRCS)EcologicalSiteDescriptions(ESDs)presentintheProjectArea.ESDsprovideguidelinesforwhichspeciesshouldoccurinplantcommunitiesindifferentrainfallzonesandsoiltypes(Miller2010).TheProjectAreaislocatedwithintheCoolCentralDeserticBasinsandPlateaus(HighPlainsSoutheast)MajorLandResourceArea(MLRA),whichreceivesanaverageof10to14inchesofrainfallperyear.ThedominantESDsarecomposedofShallowLoamy(6,652acres;30.8percentoftheProjectArea);Loamy(5,766acres;26.7percentoftheProjectArea);Sandy(3,401acres;15.8percentoftheProjectArea);ShallowSandy(1,868;8.7percentoftheProjectArea);andCourseUpland(1,119;5.2percentoftheProjectArea).Combined,theseESDscompriseapproximately17,687acres,or87percentoftheProjectArea.

Thetablesinthissection(listedbydominanthabitattype)areproposedspeciestobeseededduringreclamationandrestorationeffortsassociatedwiththeBoswellSpringsWindProject.Speciesproposedforseedingarebasedonexistinghabitattypes,commercialavailability,andcurrentlanduses.Speciessubstitutionscanbefurthertailoreddependingonlong‐termandcurrentlanduseobjectivesbythelandownerandonthedesiredhabitatsfollowingprojectrestoration.Thespecieslistedbelowareappropriatefortemporaryreclamationfollowingconstructionactivities,andforpermanentreclamationfollowingdecommissioningoftheProject.

TheapplicationrateofeachspeciesismeasuredaspoundsofPureLiveSeedsperacre(PLSlbs./ac.).NRCSrecommendsaminimumof20PLSlbs./ac.persquarefootfordrillseedingsofmostspecies.Thetablesbelowassumedrilledapplications.NRCSfurtherrecommendsdoublingtherateforbroadcastseedingandforseedingcriticalareaswheregerminationisinhibitedbylowsoilqualityorotherfactors.Theratesincludedinthetablesbelowarebetween20–30PLSlbs./ac.

Speciessubstitutionscanandshouldbeadjustedbasedonspecificsitecharacteristicssuchassoiltexture,slopeaspect,moistureavailability,andspecificlanduses.Speciessubstitutionscanbefurthertailoreddependingonlong‐termandcurrentlanduseobjectivesbythelandownerandonthedesiredhabitatsfollowingprojectreclamation.

3.1 Shallow Loamy Ecological Site Description Potentialvegetationisapproximately70percentgrassorgrass‐likeplants,10percentforbs,and20percentwoodyplants.Themajorgrassesincludebluebunchwheatgrass,westernwheatgrass,neadleandthread,andIndianricegrass.Othergrassesinclude,Sandbergandmuttonbluegrass,prairiejunegrass,bottlebrushsquirreltail,plainsreedgrass,andthreadleafsedge.Blacksagebrush,bigsagebrush,andgreenrabbitbrusharethemajorwoodyplants.

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Table 3‐1. Seed Mixes for Bluebunch Weatgrass/Rhizomatous Wheatgrass Plant Community (Shallow Loamy ESD)

ScientificName CommonName PLSlbs./ac

Pseudoroegneriaspicata Bluebunchwheatgrass 2.7

Pascopyrumsmithii Westernwheatgrass 2.5

Hesperostipacomata Needleandthread 2.6

Koeleriamacrantha Prairiejunegrass 1.5

Achnatherumhymenoides Indianricegrass 3.6

Artemisiafrigida Fringedsagewort 2.0

Achilleamillefolium Commonyarrow 1.0

Chrysothamnusviscidiflorus Greenrabbitbrush 2.0

Artemisianova Blacksagebrush 3.0

Artemisiatridentata Basinbigsagebrush 3.0

Total 23.9

3.2 Loamy Ecological Site Description Potentialvegetationincludesapproximately80percentgrassesorgrass‐likeplants,10percentforbs,and10percentwoodyplants.Themajorgrazesincluderhizomatouswheatgrass,needdleandthread,bluebunchwheatgrass,andgreenneedlegrass.Bigsagebrushandrubberrabbitbrusharethemajorwoodyplants.

Table 3‐2. Seed Mixes for Rhizomatous Wheatgrass/Needle and Thread Plant Community (Loamy ESD)





Nassellaviridula Greenneedlegrass 4.2



Boutelouagracilis Bluegrama 2.0

Sphaeralceacoccinea Scarletglobemallow 1.1


Artemisiatridentata Basinbigsagebrush 3.0

Total 25.2

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3.3 Sandy Ecological Site Description Potentialvegetationincludes75percentgrassesorgrass‐likeplants,10percentforbs,and15percentwoodyplants.Themajorgrassesincludeneedleandthread,Indianricegrass,andrhizomatouswheatgrass.Bigandsilversagebrusharethemajorwoodyplants.

Table 3‐3. Seed Mixes for Needle and Thread/Rhizomatous Wheatgrass Plant Community (Sandy ESD)



Elymuslanceolatus Thickspikewheatgrass 3.5




Poasecunda Sandbergbluegrass 2.0


Penstemonangustifolius Broadleafbeardtongue 7.2

Artemisiacana Silversagebrush 2.0

Artemisiatridentata Wyomingbigsagebrush 3.0

Total 29.0

3.4 Shallow Sandy Ecological Site Description Potentialvegetationincludes75percentgrassesorgrass‐likeplants,10percentforbs,and15percentwoodyplants.Themajorgrassesincludeneedleandthread,Indianricegrass,andbluebunchwheatgrass.Othergrassesandgrass‐likespeciesincludethickspikewheatgrass,Sandbergandmuttonbluegrass,prairiejunegrass,bottlebrushsquirreltail,plaisnreedgrass,andthreadleafsedge.Wyomingbigsagebrushandgreenrabbitbrusharethemajorwoodyplants.

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3‐4 August 2017

Table 3‐4. Seed Mixes for Mid Bunchgrass Plant Community (Shallow Sandy ESD)





Poasecunda Sandbergbluegrass 2.0


Elymuslanceolatus Thickspikewheatgrass 3.5



Chrysothamnusviscidiflorus Greenrabbitbrush 2.0

Artemisiatridentata Wyomingbigsagebrush 3.0

Total 22.9

3.5 Coarse Upland Ecological Site Description Thisvegetationcommunityevolvedwithgrazingbylargeherbivoresandiswellsuitedforgrazingbydomesticlivestock.Potentialvegetationincludes60percentgrassesorgrass‐likeplants,15percentforbs,and25percentwoodyplants.Themajorgrassesincludebluebunchwheatgrass,littlebluestem,andwesternwheatgrass.OthergrassesmayincludeIndianricegrass,prairiejunegrass,Sandbergbluegrass,andgreenneedlegrass.Bitterbrushandblacksagebrusharethedominantwoodyplants.Otherwoodyspeciesmayincludebigsagebrush,greenrabbitbrush,andserviceberry.

Table 3‐5. Seed Mixes for Mid Bunchgrass/Bitterbrush Plant Community (Coarse Upland ESD)



Schizachyriumscoparium Littlebluestem 6.0





Achilleamillefolium Commonyarrow 1.0

Amelanchieralnifolia Saskatoonserviceberry 1.0

Purshiatridentata Antelopebitterbrush 0.5

Artemisianova Blacksagebrush 3.0

Total 23.8

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4‐1 August 2017

Chapter 4 References

Miller,S.L.2010.Successfulrestorationofseverelydisturbedlands:seedingessentialforreclaimingdisturbedlands.B‐1204,April2010.UniversityofWyoming,CollegeofAgricultureandNaturalResources.

NaturalResourcesConservationService.2011.EcologicalSiteDescriptionSystemforRangelandandForestland.U.S.DepartmentofAgriculture,NaturalResourcesConservationService.Availableonline:https://esis.sc.egov.usda.gov/Welcome/pgESDWelcome.aspx.

NaturalResourcesConservationService.2008.SeedMixtureCalculatorSpreadsheet,ElectronicFieldOfficeTechnicalGuide.U.S.DepartmentofAgriculture,NaturalResourcesConservationService.

Appendix D.2 Decommissioning Cost Estimate

Project Decommission Report

Intermountain Wind LLC– Boswell Springs A 400 MW Wind farm project

Albany County, WY

June 26, 2017

Intermountain Wind , LLC| Boswell Springs Project Project Decommissioning Report

Table of Contents DECOMMISSIONING ESTIMATE GENERATL DESCRIPTION: ....................................................................... 2

DECOMMISSIONING ACTIVITIES ............................................................................................................... 3

RECLAMATION ACTIVITIES ........................................................................................................................ 4

CONCLUSION ............................................................................................................................................. 4

APPENDIX: DECOMMISIONING COST ESTIMATE ..................................................................................... 5

1


DECOMMISSIONING ESTIMATE GENERATL DESCRIPTION: The Boswell Springs project consists of 170 Wind turbine generators (WTG) with 34.5kV collection system, four power substations and 230kV transmission line system. Salvage and recycling value was not taken into consideration for this estimate. Decommissioning cost estimates were based on several sources of cost information. When possible, contractor bids from previous projects were used for equipment removal. When costs from previous projects were not available, industry standard publications, such as RSMeans cost data were used to estimate cost of decommissioning activities.

Decommissioning duration will depend on the time of year, number of crews, and equipment available. The biggest activity dictating decommissioning duration is the removal of the turbines. It is estimated that this will take a total of 8 to 9 months of this decommission the project. This estimate is based on one crane removing one turbine per day on a five day work week.

Below is description of major equipment on the project. • 25,000 Sq. ft O&M Building • 4 Substations

o 230kV metering equipment, switches and SF6 breakers. o 230/34.5kV main power transformers o 34.5kV Switchgear with vacuum breakers and 34.5 kV capacitor bank o Steel structures and equipment foundations o Fencing, grounding, and conduit o Station service power is provided by local utility and this estimate does not include the

station service transformer or utility circuit. • 34.5kV collection system

o Approximately 53 miles of 34.5kV underground collection buried 3’ deep o Approximately 9.9 miles of 34.5kV overhead collection. Assumed single wood pole

structures with 500’ between poles. • 230KV Intertie transmission line

o Approximately 13.25 miles of 230kV transmission line. Assumed wood Pole H frames structures with 750’ between structures.

• 230KV Gen-tie Line o Approximately 33.75 Miles of 230kV Transmission line. Assumed wood pole H frame

structures with 850 feet between structures. • Wind Turbine Generator

o 170 GE -2.3-116 Turbines. o 170 34.5kV/690V pad mount Generator step-up transformers (GSUs) o Assumed 55’ diameter spread footing turbine foundation 7 feet deep o Assumed 55’ by 80’ crane pad (crane pad surface 6” thick) o Assumed 40’ road section between main wind farm road and the turbine crane pad

(road surface 6” thick) o 45.5 Miles of 16’ wide (6” base and 6” surface aggregate) wind farm roads

2


DECOMMISSIONING ACTIVITIES Disconnection of the 230kV Gen-tie line at the PacifiCorp’s Freeze Out substation will be completed by PacifiCorp. The rest of the 230kV line removal will be conducted by the project decommissioning contractor. The line conductors and static wire will be removed along with the static wire and pole hardware. 230kV poles will be cut at ground level and removed from the site. The removal of the line, hardware and poles can be conducted using typical utility equipment.

Wind turbine generator (WTG) interior small electrical equipment and cabling would be removed by hand. The oil in the gear boxes will be pumped out and hauled off site for proper disposal. A large crane will be required to remove the three turbine blades, blade hub, nacelle and three tower sections per WTG. The blades will be hauled to a land fill and the towers hauled to a recycling center. The nacelles and pad mount GSU transformers will be hauled to a salvage yard or a recycling center. Conduit and grounding around the WTGs will be removed. The WTG foundations will be removed 4 feet below the surface. The rest of the foundation will be left in place. The WTG foundation areas will be filled with soil and compacted. The surface material from the turbine roads, turn ins and crane pads will be removed after the turbine have been torn down and removed.

The 34.5kV underground collection system will be dug up and removed. This estimate assumes an automated trenching devise that excavates the trench, removes the cables, and backfills the trench will be used for this work. The cables will be cut to manageable sizes and hauled to a recycling center. Fiber optics cable and conduit will be hauled to a land fill. The 230kV intertie transmission conductor, the 34.5kV overhead conductor and pole hardware will be removed using utility bucket trucks. This material will be hauled to recycling center with the underground cable. The wood poles will be cut at ground level and left for the land owner’s use or hauled to a land fill along with the non recyclable pole hardware.

Substation decommissioning will start with disconnection and removal of the substation bus and conductors. This material will be taken to a recycling center. Power transformers will be drained of oil with an oil tank truck and the oil will be hauled off site for proper disposal. The SF6 breakers gas will be vacuumed out with a gas cart and the gas bottles will be hauled off site for proper disposal or re-use. Substation steel structures, power transformers and switchgear will be removed with a small crane and loaded on trucks for removal. The substation fence will be removed and hauled to recycling center. Substation gravel will be removed and hauled off site. Concrete foundations will be removed to 4 feet below grade with the remaining foundation abandoned in place. Below grade conduits, grounding, and cabling will be completely removed and hauled off site.

Substation station service power is provided by the local utility will be responsible for removal of this equipment. This will not be part of the project decommissioning activities. Cost for removal of main wind farm roads and O&M building is not included in total cost. These are intended to be left in place for land owner use.

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