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Home My WebLink AboutCertificate of Exemption_Black River Pump Station SRP_15-000557DEPARTMENTOFCOMMUNITYANDECONOMICDEVELOPMENT—“Renton0PLANNINGDIVISIONCERTIFICATEOFEXEMPTIONFROMSHORELINESUBSTANTIALDEVELOPMENTDATE:August21,2015PROJECTNUMBER:LUA15-000557,SMEPROJECTNAME:KingCountyBlackRiverPumpStationSedimentRemovalProjectPROJECTMANAGER:ClarkH.Close,SeniorPlannerPROPERTYOWNER:CityofRenton,1055SGradyWay,Renton,WA98057APPLICANT:TomBean,KingCountyWaterandLandResourcesDivision,RiverandFloodplainManagementSection,2015.JacksonSt,Seattle,WA98104CONTACT:GeorgeRitchotte,HerreraEnvironmentalConsultants,Inc.,2200SixthAvenue,Suite1100,Seattle,WA98121PROJECTLOCATION:550MonsterRoadSWPROJECTDESCRIPTION:TheapplicanthasrequestedaShorelineExemptionfortheremovalofapproximately2,900cubicyardsofsedimentthathasaccumulatedontheconcreteforebayapronlocatedimmediatelyupstreamoftheBlackRiverPumpStation(BRPS).The10-acrestudyareaislocatedinSections13,Township23North,Range4EastoftheWillametteMeridianandisinthelowerreachesofWaterResourceInventoryArea(WRIA)9Green-DuwamishWatershed.TheprojectislocatedintheBlackRiver/SpringbrookCreekReaches(BRSC-A)whichisdesignatedShorelineNatural.Thepumpstationisawater-dependentusethatconsistsofaconcretedamthatspanstheBlackRiverchannel,witheightpumpstoconveyflowfromtheforebaybehindthedamtothedownstreamBlackRiverchannel.PlantpumpscanhandleBlackRiverflowuptoanestimated2,945cubicfeetpersecond(cfs)capacity,whichexceedsaonepercentfloodcondition.TheBRPSprovidesfloodcontrolforthelowerGreenRiverValley,andsedimentthathasaccumulatedbehindthepumpstationsinceitsconstructioninthe1970shasbecomeanoperationalconcernforthefacility.Sedimentwouldberemovedbydewateringtheworkareaandexcavatingdirectlyfromtheriverbed.Excavatedmaterialwouldbedecantedinatemporary,water-tightfacilityonthesouthriverbank.DecantedwaterwouldmeetwaterqualitystandardsbeforebeingdischargedbackintotheBlackRiver.Excavatedsedimentwouldbedisposedofatanapproveddisposalfacility. BlackRiverPumpStationSedimentRemovalProjectPage2of17August21,2015Projectworkislikelytotaketwoseasons.Constructionisscheduledtobegininspringof2016andwouldlastabout10weeksin2016and2017.In-waterworkwouldtakeplaceduringtheapprovedin-waterworkwindowofiuly1sttoAugust31standwouldlastaboutsixweeks.Thestagingareaandaccessroadconstructionwouldtemporarilyclearstreamandwetlandbuffersonthenorthandsouthsidesoftheriver,andoneshorepinewouldberemoved.Oncetheprojectiscomplete,existinggradeswouldberestoredandthestagingareawouldberevegetatedwithnativeplants.Therewouldbenopermanentalterationtohydrologyorstreambanks.Minorvegetationimpactsareaddressedinthebuffermitigationreport.KingCountyissuedaSEPAdeterminationofnon-significance(DNS)forthisproposalunderWAC197-11-340(2)onMarch5,2015.Formoreinformation,pleaseseetheattachedNoticeofActiondocument.Inadditiontothedredging,theprojectalsoincludesthefollowing:a)stagingandsitepreparation,whichwouldincludeconstructingasedimentstockpiling,decantandtreatmentareaandcranepad;b)mobilizingequipmentintheworkarea;c)isolatingthein-waterworkareawithturbiditycurtains,cofferdams,temporaryflowdiversionstructures,orotherbestmanagementpractices(BMPs);d)excludingfishfromthein-waterworkarea;e)pumpingtheBlackRiverthroughatemporarybypasspipeonthenorthsideoftheriver;f)placingsedimentremovalequipmentintheworkareausingthecrane;g)removingandstockpilingsedimentadjacenttotheriver;h)decantingstockpiledsedimentandtreatingthewastewater;i)removingin-waterBMPs;j)haulingsedimentoffsite;andk)restoringandreplantinganyclearedareas.HerreraEnvironmentalConsultants,Inc.completedaWetlandandStreamDelineationReportonMay16,2014.HerrerabiologistsdelineatedfourwetlandsandtheBlackRiverwithinthestudyarea’(Table1-attached).WetlandAandDarelocatedonthenorthsideoftheBlackRiverandWetlandBandCarelocatedonthesouthsideoftheriver.TheBlackRiverisaperennialsalmonid-bearingstreamandisthereforedesignatedbytheCityasaTypeSwater(RMC4-3-050)aswellasaShorelineoftheState(RMC4-3-090).WetlandAisariverinewetlandthatishydrologicallyinfluencedbytheBlackRiver;WetlandBisadepressionalwetlandthatgetsmostofitshydrologyfromgroundwater,aswellasstormwaterfromMonsterRoad.WetlandBdrainsintoWetlandCthroughaculvertandWetlandCisaslopewetlandthatdrainsintotheBlackRiver.Finally,WetlandDisadepressionalwetlandthatiscomprisedofprimarilyreedcanarygrass(Phalarisarundinacea),andsitsupslopeofWetlandA.Thefourwetlandsinthestudyareaarefurtherdescribedintheattachedtable(Table1).Priortodredging,astagingandsedimentstockpiling,decant,andwatertreatmentareawouldbeconstructedonthesouthsideoftherivertoavoidimpactstowetlandsandtheheronrookerynorthoftheriver.Thesizeofthestagingareaisapproximately13,359squarefeetandincludesanaccessroadtotheBlackRiver.ThestagingareaoverlapswithportionsofthebuffersofWetlandsBandC,andfallsalmostentirelywithinthe200-footregulatorybufferof1Thestudyareaisdesignatedas“NaturalEnvironment”undertheShorelineMasterProgrambecauseitmeetsthecriteriaofashorelinethatretainsthemajorityofnaturalshorelinefunctions,representsecosystemsofparticularscientificandeducationalinterest,haslargeareasofrelativelyundisturbedwetlands,andsupportsimportantwildlifehabitat,suchasheronrookeries.Page2of17 BlackRiverPumpStationSedimentRemovalProjectPage3of17August21,2015theBlackRiver.Approximately8,766squarefeetoftotalvegetationwouldberemoved:528squarefeetofcombinedWetlandCandstreambuffer;1,171squarefeetofstreambufferonly;3,825squarefeetofcombinedWetlandBandstreambuffer;2,856squarefeetofWetlandBbufferonly;and386squarefeetofcombinedWetlandB,C,andstreambuffer.Theremainingportionofthestagingarea(4,593squarefeet)wouldbelocatedonthepumpstationparkinglot.WetlandBisaCategoryIllemergentandscrub-shrubwetlanddominatedbyreedcanarygrassandHimalayanblackberry.WetlandCisaCategoryIVemergent,scrub-shrub,andforestedwetland.Thebufferforbothwetlandsisprimarilydisturbedupland,adjacenttotheparkinglotpumpstation,consistingalmostentirelyofKentuckybluegrass.Oneshorepine,whichis15inchesdiameteratbreastheight(dbh),isinthemiddleofthegrassyareaandwouldberemoved.Vegetationwithintheproposedaccessroadalignmentconsistsofseveralsmall(2-to4-inchdbh)aldersandtwosmall(2-inchdbh)Douglas-firswithanunderstoryofreedcanarygrassandHimalayanblackberry.TheBlackRiverwouldbepumpedthroughabypasspipeforthedurationofin-waterwork.FlowswouldbereroutedthroughpipesthatwouldrunalongthenorthbankoftheriverthroughportionsofthebufferofWetlandDandtheBlackRiver.Theremaybesomeminorvegetationclearinginthebypasspipealignment,resultinginasmuchas13,757squarefeetofcombinedWetlandD/streambufferimpact,androughly3,738squarefeetofstreambufferimpact.Almostallthevegetationwithinthisareaconsistsofnonnativeweedyspecies2.Notrees,shrubs,ornativewoodyvegetationwouldberemovedonthenorthsideoftherivertolaythepipe.Asaconditionofapproval,theapplicantshallclearlydelineatethelocationofthetemporarybypasspipeonthenorthsideoftheriveranditsrelationshiptotheexistingpropertyboundaries.Shouldtheroutingofthebypasspipeencroachontotheneighboringparceltothenorth(APN377920-0119),atemporaryconstructioneasementwouldberequiredbythecontractor.Sedimentwouldberemovedbydewateredmechanicalexcavation,whichwouldinvolveisolatingthesedimentremovalareafromtheriverbyconstructingatemporaryflowdiversionstructure(e.g.,cofferdam)spanningtheentirewidthoftheriver,installingtemporarypumpsandpipingtodiverttheriver,anddewateringthesedimentremovalarea.Installationofaflowdiversionstructurewouldnotrequireimpact/piledrivingtoreducenoiseimpactsonfishandwildlife.Wherepossible,pipeswouldbeplacedonexistingfillpadsandgravelaccessroads.Theworkareawouldbepartiallydewateredusingthepumpstationpumpsuntilwaterlevelsaretooloworturbiditylevelsaretoohigh,atwhichpointportablepumpswouldbeusedtoremovetheremainingwater.Theportablepumpswouldremainonsiteduringexcavationtoremovewaterthatmayseeppastthecofferdam.Waterwouldbepumpeddownstreamofthepumpstation,unlessitistooturbidtomeetEcologySurfaceWaterQualityCriteria,inwhichcaseitwouldbepumpeddirectlytotheonsitedecantfacilityfortreatmentpriortobeingdischargedbackintotheBlackRiver.2Reedcanarygrass,tansy(Tanacetumvulgare)andHimalayanblackberry.Ontheshoreline,yellowflagiris(Irispseudacorus)dominates.Page3of17 BlackRiverPumpStationSedimentRemovalProjectPage4of17August21,2015Fishcaptureandremovalwouldbeconductedbyaqualifiedbiologistandkepttotheminimumnecessarytoremovefishfromthearea.Fishwouldberemovedfromthein-waterworkzonepriortoandduringdewateringusingacombinationofseineanddipnetting.Electrofishingmaybeusedonceadultandsub-adultfishhavebeenremovedfromtheworkarea.AnyportablepumpsusedtodewatertheareawouldbefittedwithscreenstopreventfishfrombeingsuckedintothepumpsperRCW77.57.070.Netswouldbecomposedofnon-abrasivenylonmaterial.Waterthatdrainsfromthesedimentwouldbecontained,testedandtreatedpriortobeingdischargedbackintotheBlackRiver.Ifthewaterdoesnotmeetsurfacewaterqualitycriteriaitwouldbedischargedtothesanitarysewersystemorhauledoffsitefordisposal.Previoustestingindicatesthatthesedimentiscontaminated,whichmayimpactwaterdrainingfromstockpilesandthesurroundingenvironment.Dryingagentsmaybeusedtodewaterthesediment;theBlackRiverwouldnotbeexposedtodryingagents.Dewateredsedimentwouldalsobehauledoffsitefordisposalatafacilityapprovedtoacceptsuchwaste.Sediment3wouldberemovedfromtheriverbedusingconventionalexcavationequipmentsuchasclamshellbucketsorbackhoes,andstockpiledinthedewateringarea.Acranepadwouldbebuiltinthestagingareatosupportacranethatwouldliftandremoveequipmentintoandfromtheriverbed.Hydraulicdredging(usingsuctionpumpstoremovesedimentandentrainedwater)mayalsobeusedtoremovesedimentswithinthepumpbayareabehindthetrashracks.Oncedredgingiscomplete,acleansandcapapproximately1footthick(280cubicyards)wouldbeplacedoverexcavatedareasoutsidetheconcreteaprontominimizethepotentialforsedimentdisturbanceandmobilizationoffinesedimentwhentheareaisrewatered.Thisworkwouldbecompletedusingtraditionaluplandearthworkequipmenttoplacethesandcapwhiletheworkareaisdewatered.Also,alltemporaryconstructionimpactstoclearedareaswouldberevegetatedwithnativespeciesonceconstructioniscomplete.RefertotheWetlandandStreamBufferMitigationReport(AppendixB)fordetails.Theapplicantsubmittedthefollowingreports:WetlandandStreamDelineationReport(datedMay16,2015);WetlandandStreamBufferMitigationReport(datedJune23,2015);WaterQualityMonitoringPlan(datedFebruary2,2015);BiologicalEvaluation(datedMay2012);andHabitatDataReport(March12,2015).Eachreport(attached)waspreparedbyHerreraEnvironmentalConsultants,Inc.Thethreereportsdescribethesubjectprojectandtheproposedmitigationingreatdetails,includingproposedBMPs4andmethodologiesforcompletionoftheprojectmaintenancedredge.TheprojecthasalsocompletedaCulturalResourcesReport(datedApril3,2014,revisedAugust5,2014).3Basedontheprovidedreports,analyticaltestresultsonsedimentsamplesinthepumpstationforebaycontainelevatedlevelsofarsenic,cadmium,andtotalpetroleumhydrocarbons(TPH)concentrationsthatexceedtheModelToxicsControlAct(MTCA)MethodAorBcleanuplevelsforunrestrictedlanduse.Inaddition,sedimentexceedsfreshwatersedimentqualitycriteriaforTPH,bis(2-ethyihexyl)phthalate,polychlorinatedbiphenyls(PCB5),arsenic,cadmium,andnickel.Duringdredging,theworkareawouldbeisolatedusingsiltcurtains,acofferdam,orotherBMPstominimizethespreadofcontaminatedsedimentsasmuchaspossible.4BestManagementPractice(BMP)installationandremovalwouldoccurwhenthepumpstationpumpsareturnedoff,topreventpumpingturbidwaterdownstream.Page4of17 BlackRiverPumpStationSedimentRemovalProjectPage5of17August21,2015TheprojectwouldresultinunavoidableimpactstotheBlackRiver,theregulatorybufferoftheBlackRiver,andwetlandbuffers.Thestagingandstockpilingarea,andanaccessroadextendingfromthestagingareatothestreambank,wouldbelocatedwithintheregulatorybuffersofboththeBlackRiverandwetlandslocatedonthesouthsideoftheriver,resultingincombinedstreamandwetlandbufferimpactsonthesouthside.ThebypasspipewouldneedtocrossthebuffersoftheBlackRiverandawetlandonthenorthsideoftheriver.Minorclearingtosetthepipemaycausecombinedwetlandandstreambufferimpactsonthenorthside.AccordingtotheWetlandandStreamBufferMitigationReport,allimpactswouldbetemporary,andclearedareaswouldberevegetatedwithnativevegetationonceconstructioniscomplete.IncludedwithinthemitigationreportareCityofRentonregulatoryrequirements,avoidanceandminimizationmeasuresthatwereincorporatedintoprojectdesignandconstructionmethods,unavoidablebufferimpacts,andcompensatorymitigationforthoseimpacts.Forexample,theapplicantisproposingtorevegetateclearedareasata1:1ratio.NonnativevegetationsuchasHimalayanblackberry(Rubusarmeniacus),reedcanarygrass(Phalarisarundinacea,)andKentuckybluegrass(Poapratensis)wouldbereplacedwithappropriatenativespecies,resultinginnonetlossofbufferareaorecologicalfunction.Theapplicantisproposingtoestablishadiversityofnativeemergentandshrubspeciesinbufferrestorationareasthatwoulddevelopintoamaturevegetationcommunitywithadequatecoverandcomprisedofnativeplantspecies.Herreraengineersstatethatinordertoaccomplishthegoalandobjectivesofthemitigationplan,a5-yearmonitoringandmaintenanceplanwouldberequired.Theproposedmaintenancesedimentremovalprojectincludesdredgingaswellasshorelineandwetlandbufferimpacts.BelowisStaff’sanalysisoftheproject’scompliancewiththeShorelineMasterProgramrelatedtotheaboveportionsoftheproposedmaintenanceproject.Dredging:PursuanttoRMC4-3-090F.3.b.DredgingLimited,dredgingispermittedonlyincaseswheretheproposal,includinganynecessarymitigation,wouldresultinnonetlossofshorelineecologicalfunctionsandwhenproposedforfloodcontrolpurposes,andwhenapartofapubliclyadoptedfloodcontrolplan.Themaintenancedredgingisrequiredtoprotectpropertiesdownstream.ThestationisnotrunatfullcapacitywhentheGreenRiverisnearleveecapacity;excessinflowisheldinchannelstoragebehindthedam.Floodcontrolisaccomplishedbystartingthelargepumpsatanearlystageofastorm.Duringnormal,nonstormflowconditions,onlypumpP-iisusedtoregulatedischargepastthedam,typicallycyclingonandoffforafewhoursaday(usinganautomatedstagecontrolsystem).Fishmigrationfacilitiesarealsoincludedforupstreamanddownstreamfishpassagearoundthepumpstation.ConstructionwouldbeconductedduringtheJulyandAugustfishwindowwhenfishpassagefacilitiesarenotrun.ThedamisdesignedtopreventGreenRiverbackflowintotheBlackRiveranditstributaries;ithasfreeboardoverbestavailableestimatesof1percent(1%)annualexceedancefloodconditionsontheGreenRiver.AllflowpastthedamispumpedtowardtheGreenRiver.Waterlevelsdownstreamofthedamrangefrom-4.0to+21.5feetmeansealevel(MSL),dependingontidalconditionsandwaterleveloftheGreenRiver.Watersurfaceelevationsupstreamofthedamarenormallyheldintherangeof0.0to+2.0feetMSL.FlowratesbelowthedamarePage5of17 BlackRiverPumpStationSedimentRemovalProjectPage6of17August21,2015notmeasured,butvaryatanyparticulartimebasedonacombinationofBRPSpumping,GreenRiverflow,andtidalfluctuation.Assuch,itisdifficulttopredicttheflowrateofwatermovingfromthedamtowardtheGreenRiveratanypointintime.ThemonthlyaverageflowratesmeasuredatastreamgaugelocatedonSpringbrookCreekapproximately1mileupstreamoftheBRPSforJulyandAugustover4yearsofavailablerecordsare13.1and7.8cfs,respectively.Sedimentthathasaccumulatedupstreamofthepumpstationsinceitsconstructioninthe1970sisnowanoperationalconcernforthefacility.TheKCWLRDproposestoremoveabout2,900cubicyardsofsedimentfromtheriverchannel,extendingabout100feetupstreamofthepumpstation.Aspreviouslymentioned,iftheproposedmitigationplanisimplemented,theprojectwouldresultin“nonetloss”ofshorelineecologicalfunctions.RMC4-3-090F.3.d,establishesreviewcriteriafordredgingprojects;theapplicablecriteriaisaddressedbelow:1)AllproposeddredgingoperationsshallbedesignedbyanappropriateState-licensedprofessionalengineer.AstampedengineeringreportandanassessmentofpotentialimpactsonecologicalfunctionsshallbepreparedbyqualifiedconsultantsandshallbesubmittedtotheRentonPlanningDivisionaspartoftheapplicationforashorelinepermit.StaffComment:Projectiscompliantwiththeabovestandard,seeattachedreportsanddrawings.2)Theresponsibilityrestssolelywiththeapplicanttodemonstratethenecessityoftheproposeddredgingoperation.StaffComment:TheproposedmaintenancedredgingprojectisrequiredontheBRPSduetoanoperationalconcernforthefacility.Enoughsedimenthasaccumulatedupstreamofthepumpstationoverthepast44yearsthatitisnownecessarytoremovethesedimentfromtheriverbedinordertomaintainthepumpstation’sfloodcontrolcapacity.KingCountyproposestoremoveabout2,900cubicyardsofsedimentfromtheriverchannel,extendingfromthepumpstationtoapproximatelylOOfeetupstream.TheBRPSprovidesfloodcontrolprotectionforthelowerGreenRiverValley,aswellaspreventingGreenRiverbackflowintotheBlackRiveranditstributaries.3)Theresponsibilityrestssolelywiththeapplicanttodemonstratethat:(a)Therewillbenonetlossofecologicalfunctionsincludingbutnotlimitedtoadverseeffectonaquaticspeciesincludingfishmigration.StaffComment:Thebiologicalevaluationdeterminationofeffectstatesthattheprojectmayaffect,butisnotlikelytoadverselyaffect,PugetSoundChinooksalmon,PugetSoundsteelhead,andCoastal-PugetSoundbulltrout.TheprojectmayaffectPugetSoundChinook,PugetSoundsteelhead,andCoastal-PugetSoundbulltroutbecause:a)Thesespecieshavebeendocumentedinorneartheactionareaandcouldbepresentduringin-waterwork;b)Theprojectwouldcausetemporaryincreasesinsuspendedsedimentandturbidity;c)Sedimentsamplescollectedin2008containedelevatedlevelsofTPHs,metals,andothercontaminants;andd)DewateringPage6of17 BlackRiverPumpStationSedimentRemovalProjectPage7of17August21,2015thein-waterworkzonewouldrequirecaptureandrelocationoffishspecieswithinthedewateredarea.TheprojectisnotlikelytoadverselyaffectPugetSoundChinook,PugetSoundsteelhead,andCoastal-PugetSoundbulltroutforthefollowingreasons:a)Workwouldtakeplaceduringtheapprovedin-waterworkwindowwhenlistedsalmonidsareleastlikelytobepresentintheactionarea;b)Probableelevatedsummerwatertemperaturesandlowdissolvedoxygenwouldlikelydiscouragesalmonidpresenceandprecludebulltroutpresence;c)ImplementationofappropriateBMPswouldminimizeturbidityandthespreadofpotentiallycontaminatedsediments;andd)Fishremovalandhandlingwouldbeconductedinsuchawayastominimizeimpactsonanylistedspeciesthatmightbecaptured.ThebiologicalevaluationconcludesthattheproposedprojectwouldadverselyaffectEssentialFishHabitat(EFH)forPacificsalmonidsbygeneratingturbidityduringin-waterworkanddisturbingpotentiallycontaminatedsedimentsthatcouldbecomere-suspendedinthewatercolumn.Impactswouldbeshort-termandlimitedtothedurationofin-waterwork(approximately8weeksineachconstructionseason).Moreover,theapplicanthasproposedseveralproject-specificmeasuresintotheprojectdesigntoreduceimpactstofishandtheircriticalhabitat,andtheproposedmitigationplanconcludestheprojectwouldresultin“nonetloss”ofshorelineecologicalfunctions;therefore,theprojectisnotanticipatedtoresultinpermanentimpactstofishmigration.(b)Therewillbenoadverseimpactonrecreationalareasorpublicrecreationenjoymentofthewater.StaffComment:Theproposeddredgingprojectwouldnotchangepublicaccessordisplaceanyexistingrecreationaluses.TheprojectislocatedimmediatelyadjacenttotheBlackRiverRiparianForest,whichstraddlestheBlackRivernorthandeastofMonsterRdSW.TheMetroWaterworksParkislocatedsouthofMonsterRdSWwithinabout%mileoftheprojectsite.BoththeBlackRiverRiparianForestandMetroWaterworksParkprovideinformalandformalpassiverecreationopportunities.Theproposalwouldnotsignificantlyimpactrecreationopportunities,inpartbecauseanyeffectswouldbetemporary;therefore,nomeasurestoreduceorcontrolimpactsonrecreationareproposed.Inaddition,theprojectareaisclosedtothepublicandscreenedwitha6-foothighchainlinkfenceonlandandafloatingboomwithintheriver.Therefore,theprojectwouldnotresultinadverseimpactsonrecreationalareasorpublicrecreationandenjoymentofthewater.4)AdjacentBankProtection:(a)Whendredgingbottommaterialofabodyofwater,thebanksshallnotbedisturbedunlessabsolutelynecessary.Theresponsibilityrestswiththeapplicanttoproposeandcarryoutpracticestoprotectthebanks.StaffComment:ProjectactivitieswouldoccuronthenorthandsouthsidesoftheBlackRiver,aswellaswithintheBlackRiverchannel.OnthesouthsideoftheriverintheprojectareaanarrowstripofriparianvegetationapproximatelyfOfeetwideextendsalongthebank,whichrisessteeplyfromtherivertoaflatgrassyareaimmediatelyeastofthepumpstationparkinglot.ThePage7of17 BlackRiverPumpStationSedimentRemovalProjectPage8of17August21,2015proposedaccessroadwouldextendfromthepumpstationparkinglottotheriverbankthroughthevegetatedstrip(AccessRoadMap).Theaccessroutewouldincludeaminoramountofgrading,aswellas1.6cubicyardsofcutand1.8cubicyardsoffill(ElevationProfile).Plantspeciesinthislocationareprimarilywillows(Salixspp.),redosierdogwood(Cornussericea),redalder(Alnusrubra),Douglas-fir(Pseudotsugamenziesii),shorepine(Pinuscontorta),andblackcottonwood(Populusbalsamifera).Himalayanblackberry(Rubusarmeniacus)andreedcanarygrass(Phalarisarundinacea)dominatetheunderstory.Thestagingandstockpilingarea,andanaccessroadextendingfromthestagingareatothestreambank,wouldbelocatedwithintheregulatorybuffersofboththeBlackRiverandwetlandslocatedonthesouthsideoftheriver,resultingincombinedstreamandwetlandbufferimpactsonthesouthside.ThebypasspipewouldneedtocrossthebuffersoftheBlackRiverandawetlandonthenorthsideoftheriver.Minorclearingtosetthepipemaycausecombinedwetlandandstreambufferimpactsonthenorthside.Allimpactswouldbetemporary,andclearedareaswillberevegetatedwithnativevegetationonceconstructioniscomplete.(b)Ifitisabsolutelynecessarytodisturbtheadjacentbanksforaccesstothedredgingarea,theresponsibilityrestswiththeapplicanttoproposeandcarryoutamethodofrestorationofthedisturbedareatoaconditionminimizingerosionandsiltation.StaffComment:Bankimpactsareproposedbothforaccessandtemporaryimpactstoaccessforconstructionimpactswithinthedredgingarea.Aminoramountofgrading,aswellasbalanceofcutandfillwouldoccuronthesouthsideofriverbank.Theprovidedmitigationplanidentifiesimpactsfrombothreducedripariancoverfromaccessandstagingonthesouthsideoftheriveratapproximately13,359squarefeet.However,ofthattotalarea,4,593squarefeetofthatareaisgravelparkinglot;thustherewouldbe8,766squarefeetofvegetationclearing.Mostoftheclearedareaiswithinthe200-footregulatorybufferoftheBlackRiver,andoverlapswithportionsofthebuffersofWetlandsBandC(WetlandandStreamBufferMitigationReport,Figure2;Table1).Theapplicanthassubmittedafive-yearmitigationplanthatwouldrectifytemporarybufferimpactsbyrestoringbufferfunctionthroughrestorationofbuffervegetation,resultinginnonetlossofbufferareaorecologicalfunction.Theobjectiveistoestablishadiversityofnativeemergentandshrubspeciesinbufferrestorationareasthatwoulddevelopintoamaturevegetationcommunitywithadequatecoverandcomprisedofnativeplantspecies.Becausestreamaccessmaybeneededforfuturedredgingprojects,onlyshrubsandherbaceousspeciesareproposedforplanting,tominimizeremovalofwoodyvegetationinthefuture.Shrubswouldbeplanted4feetoncenter,andherbaceousspecieswouldbeplanted18inchesoncenter.Plantswouldbe,atminimum,in1-galloncontainers.Asaconditionofapproval,staffrecommendsthattheapplicantsubmitarevisedsedimentremovalprojectbufferrevegetationplanthatincludestrees,inadditiontoshrubsandherbaceousspecies,withintheproposedaccessroadalignmentandwithinthewetlandandstreambufferimpactsonthenorthsideoftheriver.Page8of17 BlackRiverPumpStationSedimentRemovalProjectPage9of17August21,2015Theapplicantstatesthattheplantmaterial5wouldbeinspectedbytheprojectbiologist,botanist,orhorticulturistbeforeacceptance,andthatpersonwouldbeon-siteduringreplacementoftopsoilandplantinstallationtoensurethattopsoilandplantsareinstalledproperly.5)AvoidanceofAdverseEffects:Theresponsibilityrestswiththeapplicanttodemonstratetheproposeddredgingwillavoidconditionsthatmayadverselyaffectadjacentpropertiesincluding:(a)Creatinganuisancetothepublicornearbyactivity.StaffComment:Overall,thedredgeprojectwouldbetemporaryinnature,withconstructionbeingconductedduringtheJulyandAugustfishwindowwhenfishpassagefacilitiesarenotrun.Theapplicanthasindicatedthatworkwouldoccurduringdaylighthours;generallyfrom7amto6pm.AllconstructionmustadheretoworkinghoursasspecifiedinRentonMunicipalCode(RMC)andhaulrouteswouldberestrictedtoarterialstreets.Thesubjectsiteisprimarilysurroundedbycommercialandindustrialdevelopmentincluding,butnotlimitedto,theBlackRiverQuery,RentonConcreteRecyclers,RepublicServices,K/PCorporation,andGraphicPackaging.Duetothelandusesinthearea(industrialandcommercial),theconstructionnoiseandpossibleextendedhaulhoursarenotanticipatedtoadverselyaffectadjacentproperties.HeronsForever,aWashingtonincorporatednonprofit,hasexpressedconcernaboutprojectimpactstoaGreatBlueHeronrookerylocatedintheBlackRiverRiparianForestnortheastoftheprojectsite.Theprojecthasbeenmovedfromthenorthsideoftherivertothesouthside,avoidingwetlandimpactsandminimizingpotentialdisturbancetotheheronrookery.TheLaketoSoundTrailislocatednearthepumpstationandusersmaybeconcernedaboutaccessanddisturbanceduringtheprojectconstruction.KingCountyParksplanstoextendaportionofthistrailnorthofthepumpstation,thetimingofwhichmaycoincidewiththissedimentremovalproject.TheprojectteamisproposingtocoordinateconstructiontimingwithKingCountyParks.Asaconditionofapproval,staffisrecommendingthattheapplicant’scontractorcoordinatewithKingCountyLaketoSoundTrailimprovementprojectmanagerduringthedurationofthedredgingproject.PortionsofthewetlandbufferofWetlandBwouldbeusedasstagingandsitepreparation,whichwouldincludeconstructingasedimentstockpiling,decantandtreatmentarea.Theflatgrassyarea,westofWetlandB,isoftenoccupiedwithtentsusedbyhomelesspeople.Thisareawouldbefencedtoprohibittrespassingintheworkzone.Basedontheexistinglanduses,compliancewithRMCconstructionhours,anticipatedcoordinationwiththeHeronsForever,KingCountyParks,regulatoryagencies,andlimitedimpactstorecreation,themaintenancedredgeisnotanticipatedtocreateanuisancetothepublicand/ornearbyactivities.5Nativeemergentandshrubspecieswouldbeplantedinthebuffers(WetlandandStreamBufferMitigationReport,Table2).Page9of17 BlackRiverPumpStationSedimentRemovalProjectPage10of17August21,2015(b)Damagingpropertyinornearthearea.StaffComment:Theprojecthasbeendesignedbyaprofessionalengineeranditisnotanticipatedthatthedredgingwouldresultinanydamagetopropertyinornearthearea.(c)Causingsubstantialadverseeffecttoplant,animal,aquaticorhumanlifeinornearthearea.StaffComment:Seeresponsesto3a.and5a.(d)Endangeringpublicsafetyinornearthearea.StaffComment:Projectconstructionwouldentail:Stagingandsitepreparation,whichwouldincludeconstructingasedimentstockpiling,decantandtreatmentarea,aswellasacranepadsouthoftheforebay;mobilizingequipmenttotheworkarea;isolatingthein-waterworkareaturbiditycurtainsorusingotherbestmanagementpractices(BMPs);installingacofferdamtoallowfordewateringofthesedimentremovalarea;placingsedimentremovalequipmentintotheworkareausingthecrane;sedimentremovalusingdredgingbucketsdeployedfromcranes,excavators,andfrontloadersandstockpiling;decantingstockpiledsedimentandtreatingthewastewater;removingin-waterBMPs;haulingsedimentoffsite;anddemobilizingequipmentandrestoringandreplantingthestagingarea.Themaintenancedredgingoperationswouldoccurbothintheriverandalongtheshoreline.Sitepreparationwouldconsistofthefollowing:flaggingtheconstructionlimits;placinghigh-visibilityfencingaroundsensitiveareas;installingTemporaryErosionandSedimentControl(TESC)measurestolimittheamountofsedimentleavingtheconstructionsite,asrequiredbytheapprovedTESCplan;flaggingtreestobeprotected;removingtreesasnecessarytomobilizeequipmentaspermittedbytheconstructionplansandspecifications;gradingandlevelingthestagingarea;andinstallingtheturbiditycurtain.Stagingwouldoccuronthesouthsideoftherivertoavoidimpactstowetlandsandtheheronrookerynorthoftheriver.6)Theapplicantshalldemonstratecontrolofcontaminationandpollutiontowater,air,andgroundthroughspecificoperationandmitigationplans.StaffComment:ThesubmittedBiologicalEvaluationaddressedBestManagementPractices(BMPs)thatareintendedtoreducetheenvironmentaleffectsofthemaintenancedredgingproject.SpecificallyPage7,dealingwithavoidanceandminimizationmeasures,suchastheuseofturbiditycurtainsandaflowdiversionstructuretoisolatethein-waterworkareaandcontrolthespreadofturbidityandcontaminatedsediments.TheContractorwoulddevelopandimplementaDredgingandDisposalPlanthatwouldaddressrequirementstomeetwaterqualitycriteria.Oncedredgingiscompleteasandcapapproximately1footthickwouldbeplacedoverthedredgedareatominimizethepotentialforsedimentmobilizationwhentheareaisrewatered.AllwaterremovedfromtheriverduringdredgingorexcavationanddecantactivitieswouldbetreatedforturbidityandtoxicsbeforebeingdischargedintotheBlackRiverdownstreamofthepumpstation.ThewaterthatisproposedtobedischargedwouldbetestedPage10of17 BlackRiverPumpStationSedimentRemovalProjectPage11of17August21,2015beforebeingreleaseddownstream;ifitdoesnotmeetsurfacewaterqualitycriteria,itwouldbedisposedofoff-site.Furthermore,itshouldbenotedthataTESCplanwouldbeimplementedduringconstructiontoreducethepotentialforerosion,a401WaterQualityCertificationisrequiredforthesubjectproject,andcompliancewiththewaterqualitystandardswouldbemonitoredduringconstructionasspecifiedintherequiredstatepermits.TheWashingtonDepartmentofFishandWildliferequireaHydraulicProjectApproval(HPA)foranyalterationofthebedorbanksoftheBlackRiverbelowtheOHWM.Receiptofthispermitiscontingentonseveralmandates,includingcoordinatingrestoration,maintainingfishstocks,andpreservingbaldeaglepopulations.BasedontheproposedBMP’SintheBiologicalEvaluationandtherequitedstateandfederalpermits,theapplicanthasdemonstratedthattheprojectwouldcontrolpollutiontowater,air,andground.7)DisposalofDredgeMaterial:Theapplicantshalldemonstratethatthedisposalofdredgedmaterialwillnotresultinnetlossofecologicalfunctionsoradverseimpactstopropertiesadjacenttothedisposalsite.(a)Theapplicantshallprovideplansforthelocationandmethodofdisposingofalldredgedmaterial.StaffComment:Theapplicanthasindicatedthatthedisposaloftheexcavatedsedimentwouldbetransportedanddisposedofoffsiteatanapproveddisposalfacility.Theapplicanthasnotidentifiedadisposallocationasitwouldbethebidwinningcontractor’sresponsibilitytoensurethatthedisposalsiteispermittedandcompliantwithanynecessaryregulations.(b)Dredgedmaterialshallnotbedepositedinalake,stream,ormarinewater,exceptifapprovedashabitatenhancementorotherbeneficialenvironmentalmitigationaspartofecologicalrestoration,acontaminationremediationprojectapprovedbyappropriateStateand/orFederalagencies,orisapprovedinaccordancewiththePugetSoundDredgedDisposalAnalysisevaluationproceduresformanagingin-water-disposalofdredgedmaterialbyapplicableagencies,whichmayincludetheU.S.ArmyCorpsofEngineerspursuanttoSection10(RiversandHarborsAct)andSection404(CleanWaterAct)permits,andWashingtonStateDepartmentofFishandWildlifeHydraulicProjectApproval.StaffComment:Seecomment7a.(c)Innoinstanceshalldredgedmaterialbestockpiledinashorelandareathatwouldresultintheclearingofnativevegetation.Temporarystockpilingofdredgedmaterialislimitedtoonehundredeighty(180)days.StaffComment:Minorclearingtosetthebypasspipe,clearingofnativevegetationwithintheaccessroad,ortemporaryimpactsforthestockpilingofdredgedmaterialmaycausecombinedwetlandandstreambufferimpactswithintheprojectarea.Allimpactswillbetemporary,andclearedareaswouldbemitigatedthroughrevegetatingtheprojectareawithnativevegetationonceconstructioniscomplete.TheprojecthasincorporatedavoidanceandminimizationPage11of17 BlackRiverPumpStationSedimentRemovalProjectPage12of17August21,2015measuresintothedesignandconstructionmethodsorincludedcompensatorymitigationforunavoidableimpactstotheBlackRiver,theregulatorybufferoftheBlackRiver,andwetlandbuffers.Constructionisscheduledtobegininspringof2016andwouldlastabout10weeksin2016and2017.Temporarystockpilingofdredgedmaterialwouldalsobelimitedtoonehundredeighty(180)days.Theapplicanthasindicatedthatonsitestagingareaconstructionwouldtemporarilyfillabout8,632squarefeetofstreamand/orwetlandbufferonthesouthsideoftheriver.Theexcavatedsedimentmaycontainupto70percent(70%)waterbyvolumeandwouldneedtobedewateredpriortodisposal.Theprojectwouldcreateasedimentstockpiling,decant,andwatertreatmentareathatwouldrequirelevelingasectionofgroundsouthoftheriver,layingdownanimperviousliner,andconstructingabermaroundtheperimetertocontainthesedimentanddecantwater.Anadditionalareawouldlikelyberequiredfortreatmentoffreewaterthatdrainsbygravityfromthesediment.Decantwaterwouldcontainarelativelyhighturbidityandmayhaveelevatedlevelsofcontaminants.Turbidwaterwouldbepumpeddirectlytotheon-sitedecantfacultyfortreatmentpriortobeingdischargedbackintotheBlackRiver.Waterwouldlikelybetreatedthroughacombinationofpumpingandsettlingintanks,sandfultrationtoremovesuspendedsolids,and,ifnecessary,carbonfultratuontoremovetoxics.Dryingagentsmaybeusedtospeedthedewateringprocess.DryingagentswouldnotbeallowedtocomeintocontactwithWatersoftheStateandanywaterdischargedtotheriverwouldmeetStateSurfaceWaterQualityStandardsforturbidityandtoxics.WaterthatdoesnotmeetwaterqualitystandardswouldbedischargedtotheseweranddirectedtothenearbyKingCountySouthTreatmentPlantfortreatmentorhauledtoapermitteddisposalfacility.Dewateredsedimentwouldbedisposedofatanapproved,off-sitepermitteduplandfacility.InadditiontothisShorelineExemption,theapplicantwouldberequiredtoobtainaconstructionpermitfromtheCityofRenton.ThispermitshallincludedetailsrelatedtoTESCPlanandStormwaterPollutionPreventionPlan.(d)Ifthedredgedmaterialiscontaminantorpollutantinnature,theapplicantshallproposeandcarryoutamethodofdisposalthatcomplieswithallregulatoryrequirements.StaffComment:TheBlackRivetislistedasimpairedonthestate303(d)listforfecalcoliformandislistedasawaterofconcernfordissolvedoxygen,temperature,andbus(2ethylhexyl)phthalate(Ecology2012).SedimentsamplescollectedbyKingCountyindicatethatthesedimentcontainslevelsofarsenic,cadmium,andTPHthatexceedtheModelToxicsControlAct(MTCA)MethodAorBcleanupleveisforunrestrictedlanduse(KingCounty2008).Inaddition,sedimentexceedsfreshwatersedimentqualitycriteriaforTPH,bis(2-ethylhexyl)phthalate,PCBs,arsenic,cadmium,andnickel.Roadrunoffovertheyearsisthelikelysourceofmostcontaminants.Backgroundturbiditylevelsareapproximately10nephelometricturbidityunits(NTU),basedonmeasurementstakenbyKingCountyupstreamofthepumpstation(KingCounty2010a,b).WaterthatdrainsfromthedredgedsedimentwouldbecontainedandtreatedpriortobeingdischargedbackintotheBlackRiver.Theextractedwaterwouldalsobetestedpriortodischarge;ifitdoesnotmeetsurfacewaterqualitycriteria,itwouldbedischargedtothePage12of17 BlackRiverPumpStationSedimentRemovalProjectPage13of17August21,2015sanitarysewersystemorhauledoff-sitefordisposal.Dewateredsedimentwouldbehauledoff-sitefordisposalatanapprovedfacility.Hydraulicdredging(usingsuctionpumpstoremovesedimentandentrainedwater)mayalsobeusedtoremovesedimentswithinthepumpbayareabehindthetrashracksduetodifficultyaccessingthatarea.Seeadditionalcommentsunder7a.(e)Permanentlanddisposalshalldemonstratethat:(1)Shorelineecologicalfunctionswillbepreserved,includingprotectionofsurfacewaterandgroundwater.(2)Erosion,sedimentation,floodwatersorrunoffwillnotincreaseadverseimpactstoshorelineecologicalfunctionsorproperty.(3)Siteswillbeadequatelyscreenedfromviewoflocalresidentsorpassersbyonpublicrights-of-way.(4)Thesiteisnotlocatedwithinachannelmigrationzone.StaffComment:StaffComment:Seecommentunder7a.Wetlands(RMC4-3-090D.2.d.x.):Activitiesthatadverselyaffectwetlandsand/orwetlandbuffersshallincludemitigationsufficienttoachievenonetlossofwetlandfunctionandvalues.Compensatorymitigationshallbeprovidedforallwetlandalteratiànandshallre-establish,create,rehabilitate,enhance,and/orpreserveequivalentwetlandfunctionsandvalues.1)MitigationsequencingshalltakeplaceintheprioritizedorderprovidedforinsectionRMC4-3-090D.2.a.iii.StaffComment:TheapplicantprovidedananalysisofmitigationsequencingintheprovidedWetlandandStreamMitigationReport,preparedbyHerreraEnvironmentalConsultants,Inc.,datediune23,2015(seepage3).Theapplicantstatesthatthisprojecthasmadeallreasonableeffortstoprovidesufficientmitigationsuchthattheprojectwouldnotresultinnetlossofbufferfunctions.Theapplicantliststheseveralwaysinwhichthiscanbeaccomplished,includingbutnotlimitedtothefollowing:theprojectcompletelyavoidedwetlandimpactsbymovingtheproposedstagingareafromthenorthsidetothesouthsideoftheBlackRiver;avoidingstreamandwetlandbufferimpactswasnotfeasibleduetotheamountofspaceneededforthestagingandsedimenttreatmentarea;accumulatedsedimentsarewithinthestreamchannel,completelyavoidingstreamimpactswouldbeunavoidable;thestagingareawassizedandlocatedtominimizebufferimpactstotheextentpossible;thestagingareawassitedtoavoidthedriplineofanylargetrees;treeclearinghasbeenavoidedtotheextentpossible;stagingandstockpilingwouldtakeplaceontheparkinglotandmaintainedlawnimmediatelyeastofthelot;bypassinganddewateringtheexcavationareawouldminimizeturbidity;allareasdisturbedbyprojectactivitieswouldberevegetatedwithnativeplantspeciesaspartoftheBufferMitigationandVegetationManagementPlan;theprojectwouldminimizeadverseimpactsonbufferareasovertimebyrevegetatingdisturbedareasimmediatelyfollowingconstruction;andlawnthatiscurrentlydominatedbynonnativegrasswouldberevegetatedwithnativeshrubandemergentvegetation.BecausetheprojectwouldcauseunavoidablePage13of17 BlackRiverPumpStationSedimentRemovalProjectPage14of17August21,2015temporarybufferimpacts,abuffermitigationandvegetationmanagementplanwasincludedintheWetlandandStreamMitigationReport.2)Wetlandalterations:Compensationforwetlandalterationsshalloccurinthefollowingorderofpreference:(A)Re-establishingwetlandsonuplandsitesthatwereformerlywetlands.(B)Rehabilitatingwetlandsforthepurposesofrepairingorrestoringnaturaland/orhistoricfunctions.(C)Creatingwetlandsondisturbeduplandsitessuchasthoseconsistingprimarilyofnonnative,invasiveplantspecies.(D)Enhancingsignificantlydegradedwetlands.(E)PreservingCategoryIorIIwetlandsthatareunderimminentthreat;provided,thatpreservationshallonlybeallowedincombinationwithotherformsofmitigationandwhentheAdministratoroftheDepartmentofCommunityandEconomicDevelopmentordesigneedeterminesthattheoverallmitigationpackagefullyreplacesthefunctionsandvalueslostduetodevelopment.StaffComment:Seecommentsundersection1-MitigationSequencing.3)MitigationRatioforWetlandBuffetImpacts:Compensationforwetlandbufferimpactsshalloccurataminimum1:1ratio.Compensatorymitigationforbufferimpactsshallincludeenhancementofdegradedbuffersbyplantingnativespecies,removingstructuresandimpervioussurfaceswithinbuffers,andothermeasures.StaffComment:TheMonitoring,SiteMaintenance,andContingencyPlanwouldensurethatperformancestandardsforbufferplantingareasareachievedandbufferfunctionsarerestored.Theclearedareaswouldberevegetatedata1:1ratiowithappropriatenativespecies.4)Location:Compensatorymitigationshallbeprovidedon-siteoroff-siteinthelocationthatwillprovidethegreatestecologicalbenefitandhavethegreatestlikelihoodofsuccess;provided,thatmitigationoccursascloseaspossibletotheimpactareaandwithinthesamewatershedsub-basinasthepermittedalteration.StaffComment:Seecommentsundersection1-MitigationSequencing.5)Protection:Allmitigationareaswhetheronoroff-siteshallbepermanentlyprotectedandmanagedtopreventdegradationandensureprotectionofcriticalareafunctionsandvaluesintoperpetuity.PermanentprotectionshallbeachievedthroughdeedrestrictionorotherprotectivecovenantinaccordancewithRMC4-3-050E4.Page14of17 BlackRiverPumpStationSedimentRemovalProjectPage15of17August21,2015StaffComment:TheprojectareaandsurroundingparcelsoftheBRPSareownedbyCityofRenton.KingCountyisresponsibleforprotectionandmaintenanceoftheBRPSandwouldalsoberesponsiblefortheestablishmentofmitigationplantsfromthesecondthroughthefifthyear,withthegoalofmeetingallapplicableperformancestandardslistedintheWetlandandStreamBufferMitigationReport.Ifpercentcoverrequirementsarenotmet,maintenanceactivitiesmayinclude,butarenotlimitedto,plantreplacement,plantsupplement,plantsubstitution,adjustmentofplantinglayouttoreflectspecificorchangingsiteconditions,weedcontrol,andinstallationandadjustmentofplantprotectiondevices.6)Timing:Mitigationactivitiesshallbetimedtooccurintheappropriateseasonbasedonweatherandmoistureconditionsandshalloccurassoonaspossibleafterthepermittedalteration.StaffComment:TheBufferMitigationandVegetationManagementPlanwouldincludeafive-yearmaintenanceandmonitoringplan.Thetimingoftheplantingwouldbescheduledtooccurduringthedormant,ornon-growing,season.Thereplacementplantingwouldoccurinyear0andfollowinginitialplanting,theplantingcontractorwouldberesponsibleformaintaining100percent(100%)plantsurvivalwithinthewetlandandbufferenhancementareasforaminimumof1yearaspertheplantingcontractplans.Theapplicant,KingCountyWaterandLandResourcesDivision,wouldberesponsibleformanagingtheestablishmentofplantsfromthesecondthroughthefifthyear.7)WetlandMitigationPlansRequired:WetlandmitigationplansshallbepreparedinaccordancewithRMC4-3-050M16.Allcompensatorymitigationprojectsshallbemonitoredforaperiodnecessarytoestablishthatperformancestandardshavebeenmet,butgenerallynotforaperiodlessthanfive(5)years.Reportsshallbesubmittedquarterlyforthefirstyearandannuallyforthenextfive(5)yearsfollowingconstruction,andsubsequentreportingshallberequiredifapplicabletodocumentmilestones,successes,problems,andcontingencyactionsofthecompensatorymitigation.TheAdministratoroftheDepartmentofCommunityandEconomicDevelopmentordesigneeshallhavetheauthoritytomodifyorextendthemonitoringperiodandrequireadditionalmonitoringreportsforuptoten(10)years.StaffComment:Theapplicanthasprovidedbothamitigationplanandassociatedplansets(JARPA)thataredesignedtoresultinnonetlossofshorelineecologicalfunctions.ThesubjectprojectalsorequiresbothFederalandStatepermits.BasedonpastexperiencethemitigationmonitoringrequirementsemployedbyboththeFederalandStatelevelaremorerestrictiveandforalongerdurationthenRentonMunicipalCodewouldrequire.Itisadvantageoustoallowtheprojecttoconductonemaintenanceandmonitoringscheduleforalllevelsofpermittingforthesubjectproject(i.e.Local,State,andFederal).Assuch,staffrecommendsasaconditionofapprovalthattheCityofRentonPlanningDivisionreceiveacopyofanyandallmitigationmaintenancemonitoringreportsthataretobeprovidedtoeithertheStateand/orFederalpermittingagencies.SECTION-TOWNSHIP-RANGE:SWYofSection13,Township23N,andRange4EW.M.Page15of17 JUNCTIONADDPORTRS21-22-23-24&25A&PORTRS26&29RENTONSHORELANDS2ND.SUPLADDBEGSWCORSEC13-23-04THE1271.74FTTHNTAPONBDRYLNBETTRS2$&29OFSDRENTONSHORELANDS2NDSUPLADD&TPOBTHCONTGN275FTTHW280.69FTTHS59-53-47W377.52FTTHS74-13-19WTOELYMGNOFCORDTHSELYALGSDELYMGNTOSLYBDRYOFSDTR29THELYALGSDSLYBDRYTOTPOBALSOBEGTPOBABOVEDESCTHN250FTTHONTANGENTCURVETORGTRADOF627.46FTTAPONBDRYLNBEGTRS26&27OFSDRENTONSHLDS2NDSUPLADDTHSWLYALGSDBDRYLNTOBEGLESSPORTIONFORCOROAD—SeeVicinityMap(attached).WATERBODYIWETLAND:BlackRiverIFour(4)WetlandsAnexemptionfromaShorelineManagementSubstantialDevelopmentPermitisherebyapprovedwithconditionsontheproposedprojectinaccordancewithMaintenanceandRepair:Normalmaintenanceorrepairofexistingstructuresordevelopments,includingdamagebyaccident,fireorelements.a.“Normalmaintenance”includesthoseusualactstopreventadecline,lapse,orcessationfromalawfullyestablishedcondition.b.“Normalrepair”meanstorestoreadevelopmenttoastatecomparabletoitsoriginalcondition,includingbutnotlimitedtoitssize,shape,configuration,locationandexternalappearance,withinareasonableperiodafterdecayorpartialdestruction,exceptwhererepaircausessubstantialadverseeffectstotheshorelineresourceorenvironment.c.Replacementofastructureordevelopmentmaybeauthorizedasrepairwheresuchreplacementisthecommonmethodofrepairforthetypeofstructureordevelopmentandthereplacementstructureordevelopmentiscomparabletotheoriginalstructureordevelopmentincluding,butnotlimitedto,itssize,shape,configuration,locationandexternalappearanceandthereplacementdoesnotcausesubstantialadverseeffectstoshorelineresourcesorenvironmentandforthefollowingreasons:Thesubjectprojectisamaintenancedredgeandthereforewouldbeconsideredregularmaintenanceandrepair.ConditionsofApproval:1.TheapplicantshallprovidetheCityofRentonPlanningDivisioncopiesofanyandallmitigationmaintenancemonitoringreportsthataretobeprovidedtoeithertheStateand/orFederalpermittingagencies.2.Theapplicantshallclearlydelineatethelocationofthetemporarybypasspipe(s)onthenorthsideoftheriverinrelationshiptotheexistingpropertyboundaries.Shouldtheroutingofthebypasspipeencroachontotheneighboringparceltothenorth(APN377920-0119)atemporaryconstructioneasementwouldberequiredbythecontractor.AsiteplanclearlyshowingthepropertyboundariesandthepathofthebypasspipePage16of17BlackRiverPumpStationSedimentRemovalProjectPage16of17August21,2015LEGALDESCRIPTION: BlackRiverPumpStationSedimentRemovalProjectPage17of17August21,2015shallbesubmittedto,andapprovedby,theCurrentPlanningProjectManagerpriortoconstructionpermitapproval.3.Theapplicantshallberequiredtosubmitarevisedsedimentremovalprojectbufferrevegetationplanthatincludestrees,inadditiontoshrubsandherbaceousspecies,withintheproposedaccessroadalignmentandwithinthewetlandandstreambufferareasimpactedbythebypasspipeonthenorthsideoftheriver.Therevisedrevegetationplanshallbesubmittedto,andapprovedby,theCurrentPlanningProjectManagerpriortoconstructionpermitapproval.4.Theapplicant’scontractorshallcoordinatewithKingCountyLaketoSoundTrailimprovementprojectmanagerduringthedurationofthedredgingproject.TheproposeddevelopmentisConsistentorInconsistentwith:ConsistentPoliciesoftheShorelineManagementAct.ConsistentTheguidelinesoftheDepartmentofEcologywherenoMasterProgramhasbeenfinallyapprovedoradaptedbytheDepartment.ConsistentTheCityofRentonShorelineMasterProgram.SIGNATURE&DATEOFDECISION:c%\)eAdkA&gi/uI%JenniferHenning,PlanningDireorDateDepartmentofCommunity&EconomicDevelopmentAttachments:.Vicinity/NeighborhoodDetailMap.WashingtonStateJointAquaticResourcesPermitApplication(JARPA)Form.HabitatDataReport,BlackRiverPumpStationSedimentRemovalProject,preparedbyHerreraEnvironmentalConsultants,Inc.(datedMarch12,2015)..WaterQualityMonitoringPlan(BlackRiverPumpStationSedimentRemovalProject),preparedbyHerreraEnvironmentalConsultants,Inc.(datedFebruary2,2015)..WetlandandStreamBufferMitigationReport(BlackRiverPumpStationSedimentRemovalProject),preparedbyHerreraEnvironmentalConsultants,Inc.(datedJune23,2015)..WetlandandStreamDelineationReport(BlackRiverPumpStationSedimentRemovalProject),preparedbyHerreraEnvironmentalConsultants,Inc.(datedMay16,2014).BiologicalEvaluation(forBlackRiverPumpStationSedimentRemovalProject),preparedbyHerreraEnvironmentalConsultants,Inc.(datedFebruary2015)..CulturalResourcesReport(datedApril3,2014,revisedAugust5,2014)..DeterminationofNon-SignificancemStockpile,Decant,waterTreatment,andStagingAreas(PathAlternatives).ElevationProfile.Table1—WetlandsDelineatedintheStudyAreafortheBlackRiverPumpStationSedimentRemovalProjectaFigure2—BlackRiverPumpStationSedimentRemovalProjectStreamandWetlandBufferImpactsUNoticeofAction—BlackRiverPumpStationForebaySedimentRemovalProjectcc:CityofRenton/OwnerPage17of17 I ...,...4..<.‘. ..:••:•••: ....“/4 c RD SW 6 sN > Black River 3779200090 r 4 :;k/ c/ I 0z :C 2 0 100 200 Q:. % N400 Feet I -Ij :Datereceived:WASHINGTONSTATEIJointAquaticResourcesPermitAgQnCreference#:_______________Application(JARPA)Form1’2Parcel#(s):___________________USEBLACKORBLUEINKTOENTERANSWERSINTHEWHITESPACESBELOWL_IPart1—ProjectIdentificationI.ProjectName(Anameforyourprojectthatyoucreate.Examples:Smith’sDockorSeabrookLaneDevelopment)[çjBlackRivetPumpStationSedimentRemovalPtoject(USACEProject#NWS-2014-1025)Part2—ApplicantThepersonand/ororganizationresponsiblefortheproject.[p]2a.Name(Last,First,Middle)TomBean2b.Organization(Ifapplicable)KingCountyWaterandLandResourcesDivision2c.MailingAddress(StreetorP0Box)201S.JacksonStreet,Room6002d.City,State,ZipSeattle,WA98104-38552e.Phone(J)2f.Phone(2)2g.Fax2h.E-mail(206)477-4638()(.)Tom.Beankingcounty.gov1Additionalformsmayberequitedforthefollowingpermits:SIfyourprojectmayqualifyforDepartmentoftheArmyauthorizationthroughaRegionalGeneralPermit(RGP),contacttheUS.ArmyCorpsofEngineersforapplicationinformation(206)764-3495..IfyourprojectmightaffectspecieslistedundertheEndangeredSpeciesAct,youwillneedtofilloutaSpecificProjectInformationForm(SPIF)orprepareaBiologicalEvaluation.Formscanbefoundathftp:HwwnwsusacegrmymilfMIssions/CvilWorks/Requlatory/PermItGuidebook/EndangeredSpecies.aspx..NotallcitiesandcountiesaccepttheJARPAfortheirlocalShorelinepermits.IfyouneedaShorelinepermit,contacttheappropriatecityorcountygovernmenttomakesuretheyaccepttheJARPA.2ToaccessanonlineJARPAformwith[help]screens,gotohttpi/wwwepermittinqwaqov/sIte/aliasresourcecenter/jarpajarpaformf9984/jarpaformp.Forotherhelp,contacttheGovernor’sOfficeforRegulatoryInnovationandAssistanceat(800)917-0043orhelp©orawa.gov.JARPARevision2012.2Page1of15 HABITATDATAREPORTBlackRivetPumpStationSedimentRemovalPtojectPreparedforKingCountyDepartmentofNaturalResourcesandParksWaterandLandResourcesDivisionKingStreetCenter-DNRP201SouthJacksonStreet,Room700Seattle,Washington981043855byHerreraEnvironmentalConsu[tants,Inc.2200SixthAvenue,SuiteII00Seattle,Washington98121Telephone:2064419080March12,2015 WATERQUALITYMONITORINGPLANBLACKRIvERPUMPSTATIONSEDIMENTREMOVALPROJECTPreparedforKingCountyDepartmentofNaturalResourcesandParksWaterandLandResourcesDivisionKingStreetCenterDNRP201SouthJacksonStreet,Room700Seattle,Washington981043855byHerreraEnvironmentalConsu[tants,nc.2200SixthAvenue,Suite1100SeatUe,Washington98121Telephone:206A419080February2,2015 WETLANDANDSTREAMBUFFERMITIGATIONREPORTBlackRiverPumpStationSedimentRemovalProjectPreparedforKingCountyDepartmentofNaturaLResourcesandParksWaterandLandResourcesDivisionKingStreetCenter-DNRP201SouthJacksonStreet,Room700Seattte,Washington98104-3855byHerreraEnvironmentalConsultants,Inc.2200SixthAvenue,Suite1100SeattLe,Washington98121Telephone:206-441-9080June23,2015DRAFT.7\,[1 WETLANDANDSTREAMDELINEATIONREPORTBlackRivetPumpStationSedimentRemovalProjectPreparedforKingCountyDepartmentofNaturalResourcesandParksWaterandLandResourcesDivisionRiverandFloodplainManagementSection201SouthJacksonStreet,Suite600Seattle,Washington98104byHerreraEnvironmentalConsultants,Inc.2200SixthAvenue,SuiteI100Seattle,Washington98121Telephone:206/441-9080Mayi6,2014Draft4:33 LBIOLOGICALEVALUATIONusArmyCorpsFORINFORMALESACONSULTATIONFor:BlackRiverPumpStationSedimentRemovalProject(CorpsReferenceNumber)Version:May2012**Thisformisforprojectsthathaveinsignificantordiscountableimpactsonlistedspecies.Itcontainsalltheinformationrequiredforabiologicalevaluation,butinabbreviatedformandwithminimalinstructionsonhowtofillitout.formoredetailedinstructions,aformatfordevelopmentofabiologicalassessmentorbiologicalevaluationcanbefoundontheSeattleDistrictCorpswebsite(www.nws.usace.army.mil—clickonregulatoryandthenonendangeredspecies,BATemplate).YoumayalsocontacttheCorpsat206-764-3495forfurtherinformation.DrawingsandPhotographs—Drawingsandphotographsmustbesubmitted.Photographsmustbesubmittedshowinglocalarea,shorelineconditions,existingoverwaterstructures,andlocationoftheproposedproject.Drawingsmustincludeavicinitymap;plan,profile,andcross-sectiondrawingsoftheproposedstructures;andover-andin-waterstructuresonadjacentproperties.(Forassistancewiththepreparationofthedrawings,pleaserefertoourDrawingChecklistlocatedonourwebsiteatww’vnwsusace.anny.milSelectRegulatory—Regulatory/Permits—Forms.)Submittheinformationto:U.S.ArmyCorpsofEngineers,RegulatoryBranch,P.O.Box3755,Seattle,Washington98124-3755.Date:February52015SECTIONA—GeneralInformation1.Applicantname:TomBean,KingCountyWaterandLandResourcesDivisionMailingaddress:201SJacksonSt.,Rm600,Seattle,WA98104-3855Workphone:Cellphone:Email:Fax:206-477-4638206-979-8270tom.beankingcounty.gov206-205-51342.Joint-useapplicantname(ifapplicable):Mailingaddress:Workphone:Homephone:Email:Fax:3.Authorizedagentname:GeorgeRitchotte,HerreraEnvironmentalConsultants,Inc.Mailingaddress:22006thAvenue,Suite1100,SeattleWA98121Workphone:Cellphone:Email:Fax:(206)787-8288206-356-0511gritchottehc1Tcrainc.com(206)441-91084.Locationwhereproposedworkwilloccur:Address(streetaddress,city,county):550MonsterRd,Renton,KingCounty,WAParcel#377920-0090Locationofjoint-useproperty(streetaddress,city,county):sameasaboveWaterbody:BlackRiver,tributarytotheGreenRiver(WRIA9;FIUC171100130001)1/4Section:SWSection:13Township:23NIRange:4ELatitude:47°28’31.34”NLongitude:l22°144l.39”W KingCountyHistoricPreservationProgramCulturalResourcesReviewProjectName:BlackRiverPumpStationForebaySedimentRemovalProjectNo.:1120590TaskNo.:AwardNo.:114194DateRequested:2/7/14Reviewer(s):PhilippeLeTourneau,CharlieSundbergReviewDate:4/3/14(revised8/5/14)FederalUndertaking?Yes—USACEpermitDepartment/Division/Section:DNRP/WLRD/RFMSContact:ErikPetersProjectLocationStreetAddress:II10MonsterRoadSW,Renton,WA98055.Parcels:3779200119,3779200090.SummaryProjectDescriptionKingCountyWLRDplanstodredgeintheconcrete-linedforebayoftheBlackRiverPumpStationandadjacentconcrete-linedriverchannel(dredgingarea)toremoveaccumulatedsedimentsincethechannelwasconstructedintheearly1970s.Dredgedsedimentswillbedewateredandprocessedinajust-over-i-acreareanorthandadjacenttothepumpstation(dewateringarea).Thedewateringareawillbedisturbedforsitepreparation(includinggradingandtreeremovalandgrubbing)andrestorationtoadepthoflessthan2feet.KingCountyHPPreviewedtheBlackRiverPumpStationFuelUpgradesProjectinparcel3779200090inMarch2013.Grounddisturbancefortheprojectwas18msouthwestofthecurrentproject’sdredgingarea.Becauseallgrounddisturbanceforthatprojectwaswithinartificialfill,werecommendedthatnoarchaeologicalworkwasnecessarypriortoconstruction.KnownCulturalResourcesWithinorAdjacenttoAreaofPotentialEffects(APE)HistoricRes.Inventory:SouthWaterTreatmentPlant(3056),230mto5,willnotbeaffected.NoneinAPE.OtherAbove-GroundHistoricResources:TheBlackRiverPumpStationwasconstructedintheearly1970s,butdoesnotappeartobeindividuallyeligibleforNationalRegisterlisting.ArchaeologicalSites:Onehistoricsite(45Kl538)15m,twoprehistoricsites(45Kl267,45Kl438)480m;noneinAPE.UBurkeMuseumReportedSites:None.EthnographicPlaces:Villagesite(7047)120m,threegeographicfeatureswithethnographicnames(7048,7160,7161)65-250m,mythologicalplace(7049)355m;noneinAPE.GLOMap(1862,1863)Features:TheAPEisintheC.E.BrownellDonationLandClaim.LIOtherDAHPSites(cemeteries,etc.):None.InformationfromHistoricMaps,AerialPhotographs,OtherSources:TheAPEhasbeenloggedatleastonce:the1897TacomaLandClassificationMapshowstheAPEas“Cut...notrestocking”.AccordingtoWLRD,thepumpstation,itsconcrete-linedforebayandchannel,andexcavationofanewriverchannelwascompletedintheearly1970s.Comparisonof1969engineeringdrawingsforconstructionofthepumpstationand2012drawingsforthecurrentprojectshowsthat8.5-16.5ftofartificialfillwasplacedinthecurrentdewateringareaaspartofpumpstationconstruction.The1969drawingsshowexistingelevationsof12-14ftandplanned1 KingCountyWaterandLandResourcesDivisionDepartmentofNaturalResourcesandParksKingStreetCenter201SouthJacksonStreet,Suite600Seattle,WA98104-3855206-296-6519Fax206-296-0192flYRelay:711DeterminationofNonSignificanceNameofProposal:BlackRivcrPumpStationForcbaySedimentRemovalDescriptionofProposal:KingCountyplanstoremoveabout2,900cubicyardsofsedimentthathasaccumulatedontheconcreteforebayapronlocatedimmediatelyupstreamoftheBlackRiverPumpStation.SedimentthathasaccumulatedupstreamofthepumpstationsinceitsconstructionintheI970sisnowanoperationalconcernforthefacility.Sedimentwillheremovedbydewateringtheworkareaandexcavatingdirectlyfromtheriverbed.Excavatedmaterialwillhedecantedinatemporary,water-tightfacilityonthesouthriverbank.DecantedwaterwillmeetwaterqualitystandardsbeforebeingdischargedbackintotheBlackRiver.Excavatedsedimentwillbedisposedofatanapproveddisposalfacility.LocationofProposal:lieprojectsiteislocatedat550MonsterRoadSWintheCityofRenton.ThepropertyislocatedintheSW¼ofSection13,Township23N,andRange4Efl.ResponsibleOfficial:MarklsaacsonPosition/Title:DivisionDirector.WaterandLandResourcesDivision4ddress201SouthJacksonSiltSSuite6OSeattleW%9%lOyl-3855DATEI_SIGNAlU1th//&!t_ProponentandLeadAgency:KingCountyDeparimcntofNaturalResourcesandParksWaterandLandResourcesDivisionContactPerson(s):KerryBaumanEnvironmentalScientistIII206-477-4637 SOUTH AREA CONSTRUCflON NOTES: 1 .SEE SHEEr C_?FOR EROSION CONTROL REQUIREMENTS.2.CLEAR AND GRADE AS NEEDED TO STOCKPILE, DECANT,TREAT WATER,AND STAGE ALL EQUIPMENT,SUPPLIES AND MATERIALS W1THIN ThEuurrsOFWORKSHOWN.UPON COMPLETION OF WORK,RE—VEGETATE ALL DISTURBED GROUND,SEE SHEET CS. 3.CONSTRUCT A UNED AND COVERED SEDIMENT STOCKPILE/DECANT AREA,SEE SHEEr C4. COLLECT AND TREAT ALL WATER ThAT DRAINSFROMThESEDIMENTSTOCKPILETOMEETThE SPECIFIED WATER OUAU(REQUIREMENTS PRIOR TO DISCHARGE TO THE BLACK RIVER. 4.ALLOW SUFFiCIENT liME IN ThE CONSTRUCTION SCHEDULE TO SAMPLE STOCKPILED SEDIMENT AND COMPLETE LABORATORY TES11NG FOR DISPOSALFACIUTfCHARACTERIZATIONANDACCEPTANCE,AS INDICATED IN ThE SPECIFICATiONS. 5.REMOVE SEDIMENT/MATERIAL DROPPED,WASHED OR TRACKED BY VEHICLES OUTSIDE OF THE PROJECT WORK UMGS.6.UPON COMPLETION OF WORK.EXISTING GRAVEL ACCESS ROADS SHALL BE GRADED AND RESTORED TO PRE—CONSTRUCGON CONDS1ONS. WORK UIMIT AND WEILAND CONTROL POINTS I NORTHING EASTINGCONTROLPOINT I •:See AttachEd •:..• Pr AA .........V • ACCESS ••• ._—-1 —.II V // V _z -AND STANC AREA /..-‘SOUTH OF PUMP STATION Tfl(VPII F flEflANT I...——I[20 0 20 40 10 z 1’’ ,.,.V V •V •,:.,..‘V \.•,\\../ V •,‘\fr ...-.\• \\,\VV../.•V \.V.,.\\Vs.._z ...‘V....5 V.\\V 5 / —— RD \\ o7 NORTH AREA CONSTRUCTION NOTES: 1.AREA SOUTH OF CONSTRUCTION LIMSS/WEILRND CAN BE USED FOR STAGING.BYPASS PIPE/PUMP SYSTEM.AND CONTAINED WATER TREATMENT SYSTEM.ACCORDING TO SPECIFICATiONS.2.SEE SHEEt C_?FOR EROSION CONTROL REQUIREMENTS.3.UPON COMPLETION OF WORK.EXISTING GRAVELACCESSROADSSHALLBEGRADEDANDRESTORED TO PRE—CONSTRUCTiON CONDITIONS. LEGEND: ———UMGS OF WORK ,V V••5 :WSTLEND BOUNSARY .CONTROL POINT STAGING AREA NORTH OF PUMP STATION ‘G.D BOOK:XX—SSXX1 APPR0!D: =ZL.•:=T.BEHN,E.PETERS 2/2015 KC:1044885 L King County STA11ON HEGKIO SASS o:::::2/2015 AROJECT N HC 1709457 DRAFT 1 007 1;7oBOwS ?rDd 8ED4T AOVAL NUM REWSION BY BOD • E UNDQUIST 2/201.X WATER IWAT4T’,SHESTS M4SFA4NE*2 Profile A-A Along Access Route Centerline Existing Grade t Proposed Temporary Grade Approx.Cut =4.lsfx 10/27 —1.6 CY Approx.Fill =5 sfx 10/27 1.8 CY Cut/Fill Area =25 x 10 -250 sf Approx.Area of Disturbance 48’x 10 —480 sf Table1.WetlandsDeifleatedintheStudyAreafortheBlackRiverPumpStationSediment1.3acresI7O3s0.03acres1,220sq.0.04acresi,945sq.0.93acresI40,300sq.ft.a....usFishandWildlifeServiceclassificationisbasedonCowatdmnetal.(1979)palU5treforested(PFO),palustrinescrub-shr(PSS),andpalustrineergent(PEM).byrogeomOrPhicclassificationisbasedonBrinson(1993).CWetlandcategorY15basedonthesh1ngt0nStateDepartmentofEcology(Ecology)wetlandratingsystem(Hruby2004),whichisrequiredforwetlandsinRentonwithinShorelinejurisdicti0I(RMC4-3-090).UWetlandbufferwidthsarebasedonRMC4-3-090. V.-LegendStagingareaWetlandandstreambufferimpactStreambufferimpactWetlandbufferimpactz:!WetlandbufferDelineatedwetland;•c’•SLrFigure2.BlackRiverPumpStationSedimentRemovalProjectStreamandWetlandBufferImpacts.03060120HERRERABing,Aerial(2014) KingCountyWaterandLandResourcesDivisionDepartmentofNatur&ResourcesandParksKingStreetCenter201SouthJacksonStreet,Suite600Seattle,WA98104-3855206-477-4800Fax206-296-0192YrYRe!ay:711NoticeofActionBlackRiverPumpStationForebaySedimentRemovalProjectNoticeisherebygivenunderSEPA,RCW43.%IC.080,thattheWaterandLandResourcesDIvision(WLRD),KingCountyDepartmentofbaturalResourcesandParks,CapitalProjectsSection,tooktheactiondescribedinitem2belowonMarch31,2015.1.Anyactiontosetaside,enjoin,review,orotherwisechallengesuchactiononthegroundsofnon-compliancewiththeprovisionsofChapter43.21CRCWshallbecommencedonorbeforeMay8,2015.2.TheagencydecisionistoproceedonfinaldesignandconstructionoftheBlackRiverPumpStationForebaySedimentRemovalProject.3.Theproposedprojectislocatedat550MonsterRoadSWintheCityofRenton.TheproperlyislocatedintheSW¼ofSection13,Township2%N,andRange4BW.M.. .4,ADeterminationofNon-SignificancewaspublishedandopenedforreviewandpubliccommentfromMarch10,2015throughMarch24,2015.ProjectsupportdocumentationandprojectsitemapsareavailableforreviewatWLRDOfficesfrom8:30a,m.to4:30p.m.weekdays.TheofficesarelocatedatKingStreetCenter,201SouthJacksonStreet,Suite600,Seattle,Washington98104.KerryBaumanistheProjectEcologistandmaybecontactedat206477-4637.5,ADecisiontoProceedwassignedonMarch31,2015byMarkIsaacson,WLRDDivisionDirector.ThisNoticeofActionwasfiledonApril10,2015andwillcontinueineffectthroughMay8,2015.