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DrainageReport_20170511_Resub.pdf RECEIVED 05/11/2017 Development Services Ctr. City of Edmonds STORMWATERSITEPLAN DRAINAGEREPORT FOR WESTGATE WOODS 9511-9513EDMONDSWAY EDMONDS,WASHINGTON Based on 2012/2014 Department of Ecology Stormwater Management Manual. STORMWATER SITE PLAN DRAINAGE REPORT FOR WESTGATE WOODS 9511-9513 EDMONDS WAY EDMONDS, WASHINGTON 98020 April 11, 2017 Based on 2012/2014 Department of Ecology Stormwater Management Manual. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc SNOHOMISHCOUNTYISLANDCOUNTYSKAGITCOUNTY th 125EMainSt,Suite104 Ȟ POBox516840SE8Avenue,Suite102603SouthFirstStreet Monroe,Washington98272OakHarbor,Washington98277MountVernon,Washington98273 tel:360.794.7811 Ȟ fax:360.805.9732tel:360.675.5973 Ȟ fax:360.675.7255tel:360.336.9199 Ȟ fax:360.982.2637 ¶¶¶ȁ( ±¬²¤)¢ȁ¢®¬ STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 1 Figure1:VicinityMap PROJECTOVERVIEW ThisStormwaterSitePlanhasbeenpreparedforWestgateWoods,amultifamilyresidential projectlocatedat95119513EdmondsWayinEdmonds,WA.Thistwoparcelparentlothasa an combinedareaof0.58acresandproposestwo,5unitresidentialbuildingswithgaragesand th Frontageas internaldriveaisle.Curb,gutterandsidewalkisalsobeingaddedalongthe228 wellasapproximately2ftoflanewidening. SeeFigure1:VicinityMapforgraphiclocationandFigure3:DevelopedSitefortheproposed siteplan. Thesiteiscurrentlyundeveloped.SeeFigure2:ExistingConditions. METHODOLOGY Per2012/2014DepartmentofEcologyStormwaterManagementManual,allMinimum Requirementsarerequired.Thesiteachieves100%infiltrationofstromwaterrunoff. Thedrainagedesignfortheprojecthasbeenpreparedbasedontherequirementsofthe2012 DepartmentofEcologyStormwaterManagementManual(DOEManual)with2014revisions P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 2 asshallbeadoptedbytheCityofEdmondsinearly2017.Inaddition,thisreportusesdesign guidelinesprovidedbytheLowImpactDevelopmentTechnicalGuidanceManualforPuget Sound.WWHM2012(AKAWWHM4)asprovidedbyDOEhasbeenusedfordeterminingbasin runoffandforsizingofthestormwaterfacilities. BasedontheflowchartinFigureI2.4.1ofDOEManual(attached)andthesiteparameters,the projectissubjecttoallMinimumRequirements(MR19). TheprojectsiteparametersperFigureI2.4.1are: Theexistingsitehaslessthan35%existingimperviouscoverage. Theprojectdoesresultin5,000sforgreaterofnewhardsurfacearea. Thereforeallminimumrequirementsapplytothenewandreplacedhardsurfacesand convertedvegetationareas. MR1:PREPARATIONOFSTORMWATERSITEPLANS DRAINAGEPLANDESCRIPTION Directprecipitationisthesourceofonsitestormwaterandallexistingstormwaterappearsto completelyandrapidlyinfiltrateonsite.Geotechsiteanalysisconfirmsinfiltrationcapablesoils withnohydricsoilspresentandnoindicationofwetlandorothersensitiveareasareknownon site. Proposedstormwaterrunoffshallberoutedfortreatmentandcompleteinfiltrationviaonsite bioretentioncellwithoverflowconnectivitytothepublicstormsystembeneaththeadjacent 9ķƒƚƓķ͸ƭWay.AninfiltrationtrenchisalsoprovidedtoaccommodateThisprojectexpectsno contributionofstormrunoffintothepublicstormconveyancesystem. WATERQUALITYMEASURES FollowingisalistoftheproposedconstructionwaterqualityBMPs.Thesearediscussedfullyin theProjectSurfaceWaterPollutionPreventionNarrativeunderseparatecover.Theproposed BMPsareasfollows: BMPC101,PreservingNaturalVegetation BMPC103,HighVisibilityFence BMPC105,ConstructionEntrance BMPC106,WheelWash BMPC107,ConstructionRoad/ParkingAreaStabilization BMPC120,TemporaryandPermanentSeeding BMPC121,Mulching BMPC123,PlasticCovering BMPC125,Topsoiling/Composting BMPC130,SurfaceRoughening P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 3 BMPC140,DustControl BMPC150,MaterialsOnHand BMPC151,ConcreteHandling BMPC152,SawcuttingandSurfacingPollutionPrevention BMPC153,MaterialDelivery,StorageandContainment BMPC154,ConcreteWashoutArea BMPC160,CertifiedErosionandSedimentControlLead BMPC200,InterceptorDikeandSwale BMPC201,GrassLinedChannels BMPC207,Checkdams BMPC209,OutletProtection BMPC220,StormInletProtection BMPC233,SiltFence BMPC241TemporarySedimentPond PostConstructionBMPswouldinclude: MaintenanceofStormwaterDrainageandTreatmentSystems Parkinglotsweeping DETENTIONSIZING WWHM12fromtheDepartmentofEcologywasusedfortreatmentanddetentionsizing. CalculationsandsizingarediscussedfurtherinMR7.Roofdischargeforunits15isperBMP T5.10A. CONVEYANCECALCULATIONS ConveyancecalculationsareprovidedinMR5. STORMWATERTREATMENT.at͸{ TherunofffromthenewPGISonsitewillflowtoabioretentioncellsizedinMR6. PROTECTIONOFWETLANDS Therearenocriticalareaslocatedonthesite. OPERATIONSANDMAINTENANCE Thespecificrequirementsfortheongoingoperationandmaintenanceoftheproposedstorm watersystemsisdetailedinMinimumRequirement#10. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 4 EXISTINGCONDITIONSSUMMARY DESCRIPTION WestgateWoodsisproposedtospantwoadjacent,undevelopedparcelslocatedat95119513 Edmonds,WayinEdmonds,WA.Thesiteisboundonthreesidesbyexistingstreetswithstorm thth drainsystems.Alongthenorthsidelies228StreetSW,theshorteastsideisboundby95 PlaceWest,andthesouthedgeisfacedEdmondsWay/SR104.Thefourthsideabutsa developedresidentiallot.Althoughthesiteisatopographicallyalocallowpoint,thereisno evidenceonsheet,shalloworchannelflowonsitefromadjacentpropertiesnoristhereany evidenceofdamporpondingareas.Thewesthalfofthesite,approximately,hasaratherflat floorwithsidesthatclimbwestandnorthandeast.Theeasthalfofthesitecontainsasecond flatfloorthatrisesagainalongtheeasternedge.Thesouthsideofthesiteabutsthetoeofa2 to4fttallrockerythatretainsEdmondsWay.Thesiteiscurrentlyvegetatedwithtreesand understoryoveracombinedareaof0.58acres. SeeFigure1:VicinityMapforgraphiclocationandFigureFigure2:ExistingConditions. Figure2:ExistingConditionsperSnohomishCountySnoSCAPE SOILSDESCRIPTION Geotest,Inchaspreparedageotechnicalreportforthesitetitled DĻƚƷĻĭŷƓźĭğƌ9ƓŭźƓĻĻƩźƓŭ LƓǝĻƭƷźŭğƷźƚƓ,datedJune10,2016andisattachedasappendixB.Fivetestpitswereexplored todepthsof7.5to10ftdeepviaanexcavator.Depthsnear4.5to8ftdeepencounteredgravelly sandandadvancedoutwashsoils.SoilsampleswerealsoclassifiedviatheUSDAsoil P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 5 classificationsystemandincludeloamysandandsandandratedatЋͼperhourinfiltrationrates inthevicinityoftheproposedbiocell.TheWWHM12calculationswereconducted conservativelywithaninfiltrationrateof2in/hrandaKsatfactorof4. CationExchangeCapacity(CEC)testswerealsoconductedfornearsurfacematerialsandfound tomeetorexceedDOEcriteriaforCECandorganiccontentforuseinstormwatertreatment processes.Thenearsurfacematerialmaybeusedforwaterqualitytreatment,and/orbe amendedfurthertomeetamendedsoilcriteriaasperDOE. EXISTINGBASIN thth Theexistingbasinisboundtothenorthby228SW,totheeastby95PlaceW,andtothe southbyEdmondsWay.Thewestedgeisboundbyatopographicbreakapproximately500ft westsouthwestandapproximates2.5acres.Thebasiniswellvegetatedandcontainsamixof emptyparcelsandsinglefamilyresidences. UPSTREAMANALYSIS Thebasinhasnoapparentwatercoursesthatleadtothesubjectsite.Allstormwaterappears tobeoriginatedasdirectrainfallandalsoinfiltratesorisconsumedbythevegetation. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 6 DOWNSTREAMANALYSIS Thissiteisatopographiclocallowandnoflowcurrentlyleavesthesite.Withnoapparent watercoursesonsite,theexistingstormwaterappearstoinfiltratorandorbeabsorbedbythe vegetationsuchthatnofloweverleavesthesite. Proposedconditionscontainabiocellforwaterqualitytreatmentandinfiltration.Calculations show100%infiltrationonsite.Anoverflowviatightlineintothepublicstormsystembeneath EdmondsWayisalsoproposed.Treecreditsforstormwaterabsorptionhavenotyetbeen applied. ThissitedoesnotanticipateanycontributionstotheCitystormsystemandtodownstream flow. TheCitystormsystemfollowsEdmondsWaytoastormwateroutfallintoPugetSoundnearthe southsideoftheEdmondsMarina. CAPACITY TheexistingstormsystembeneathEdmondsWayisaЌЏͼdiaconcretestormpipethat th eventuallyconnectstoaЍЋͼcmp,whichbecomesЍБͼconcretepipeatthe100street crossing.Theexistingstormsystemhasnocapacityconstraints. MR2:CONSTRUCTIONSTORMWATERPOLLUTIONPREVENTION ADepartmentofEcologySurfaceWaterPollutionPreventionPlanwillbepreparedunder separatecoverandsuppliedwithconstructionplansanddrainagereport. MR3:WATERPOLLUTIONSOURCECONTROL CONSTRUCTIONSTORMWATERBMPs ConstructionsourcecontrolsarecoveredundertheSWPPP PERMANENTSOURCECONTROLBMPs Thefollowingsourcecontrolsapply: Containerstorageofwastes; Vegetationmanagement; Cleaningofpavedsurfaces; Stormdrainagemaintenance; P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 7 MR4:PRESERVATIONOFNATURALDRAINAGE Naturaldrainageispreserved. Thepredevelopedachievescompleteinfiltrationandthedevelopedconditionsachieves completeinfiltrationaswell.Nodrainagecoursesarealtered. MR5:ONSITESTORMWATERMANAGEMENT Per2014DOE,Volume1,Table2.5.1,thisisanewdevelopmentinsidetheUGAandisrequired tomeetMinimumRequirements#19.Assuch,thesiteshallmeettheLowImpact DevelopmentPerformanceStandardandBMPT5.12;oruseList#2attheğƦƦƌźĭğƓƷ͸ƭoption. ThisprojectisoptingtomeettheLowImpactDevelopmentPerformanceStandardanduse BMPT5.13. LowimpactDevelopmentStandardsareachievedbyinfiltrating100%ofthestormwaterrunoff, thuspostdevelopmentdischargeratesofzeroarelessthan8%ofthe2yearpeakflowandless thanallofthe50yearflow. BMPT5.13PostConstructionSoilQualityandDeptharerequiredfordisturbedsoilsthatshall bevegetated. BMPT5.10ADownspoutFullInfiltrationisusedforbuildings15. BMPT7.30Bioretentioncellisusedtomanagebuildings610andallotheronsitehardscape, withahorizontalsurfaceareaofatleast5%ofthecontributingareatothatbiocell. Additionally,shouldList#2bedesired: LawnandLandscapedAreas: 1)PostConstructionSoilQualityandDepth:BMPT5.13willbeimplementedondisturbed andlandscapedareas. RoofAreas: 1)FullDispersionisnotpracticalonthissitedueflowpathlengthsandproximityto boundariesorstructures; 2)BMPT5.10ADownspoutFullInfiltrationSystemsmaybeusedinMediumSandat30LF (of2ftwidetrenchorareaequivalent)forevery1000SFofcontributingroofarea.Theuse ofdownspoutinfiltrationmaybeusedtoaugmentabioretentionfacilityforrooftop stormwatermanagement.RooftopsmayalsobedirectedtoaBMPT7.30Bioretention facility. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 8 3)BMPT7.30BioretentionCellwillbeused.Theprojectedareaofthecellsmusttotalat least5%ofthetributaryroofarea. PavementAreas: 1)FullDispersionisnotpracticalonthissitedueflowpathlengthsandproximityto boundariesorstructures; 2)PermeablePavementisanoptionofequalsignificancetobioretention.Abioretention facilityhasbeenchosenratherthantheuseofpermeablepavement. 3)Bioretention:Asinglebiocellisproposedforthissite.Theprojectedareaofthecell musttotalatleast5%ofthetributarypavedarea. th Theproposedfrontagesidewalkalong228hasalongitudinalgradethatvariesfrom5%to nearlyflatandshallhaveanadversecrossslopetodirectsidewalksheetflowontotheproject site.Thesheetflowshallnaturallydisperseintonativevegetationand/orBMPT5.13treated soilwithaflowpathof1520ftoveranA/Bnativebaseandachievetotalinfiltration.This sidewalkdoesnotreceiveflowfromanypollutiongeneratingsurface. th Aproposedcatchbasinlocatedin228isproposedtocatchanareaequivalenttothenewly widenedpavementarea.Theproposedcatchbasinshalldirectitsdischargeintotheonsite bioretentionfacilityforwaterqualitytreatmentandinfiltration. Becausethebiocellhasasurfacearearequirementof5%ofthecontributingarea,andthe biocellhaslimitedspaceavailable,rooftops15weredirectedtoaninfiltrationtrench calculatedperBMPT5.10ARoofInfiltrationforMediumSandysoil(30Lfof2fttrenchper1000 SFofcontributingroofarea).AnequivalenttrenchareashallmeetorexceedBMPT5.10A requirements. Thefollowingcontributingareasaretabulatedasfollows: FacilityContributingAreaRequiredAreaProvidedArea (SF)(SF)(SF) BMPT7.30Biocell12,861(min5%)643690 BMPT5.10ARoofInfiltration4,050135150 P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 9 MR6:RUNOFFTREATMENT Withmorethan5,000sfofpollutiongeneratingimpervioussurfacethesiterequiresrunoff treatment. OilControl:Thesitedoesnotmeetthethresholdof100vehiclesperday/1,000sfofbuilding area;oilcontrolisnotrequired. PhosphorousControl:Wehavereviewedthe303dlistingandtherearenowaterbodieslisted inthelocalarea. EnhancedTreatment:Enhancedtreatmentisrequiredwhenacommercialsitedischarges directlytofreshwatersorconveyancesystemstributarytofreshwatersdesignatedforaquatic lifeuseorthathaveanexistingaquaticlifeuse.Thissiteproposedcompleteinfiltrationand emergencyoverflowdischargetotheCitysystem.Bioretentionistheproposedmethodof runofftreatmentanddoesmeettherequirementsforEnhancedTreatment. However,EnhancedTreatmentisprovidedandachievedbytheuseofaBMPT73.0 Bioretentioncell.ThebiocellcontainsimportedsoilmixandprovidesEnhancedTreatmentif 91%oftherunoffrequiringtreatmentpassesthroughthemix.AllPGISisdirectedtothebiocell and100%ofthatflowpassesthroughthemedia. BIORETENTIONCELLS RunoffTreatmentwillbeaddressedthroughthedesignandinstallationofaBMPT7.40 Bioretentioncell.Bioretentioncellsincorporateamendedsoilsandvegetationthatusethe chemical,biological,andphysicalpropertiesofplants,microbes,andsoilstoremove,orretain, pollutantsfromstormwaterrunoffpriortoinfiltration. The2012/2014SWMMhasͻźƓŅĻğƭźĬźƌźƷǤĭƩźƷĻƩźğͼforbioretentionandraingardenfacilities, whichrequirestheuseofdoublenegativedescriptionstoallowtheuseofsuchproducts.The followingisincludedper2012/2014SWMM,butessentiallystatesthattheuseofbioretention isnotinfeasible(Bioretentionisthereforefeasible). IfitpleasestheCity,thisinfeasibilitysectionwillgladlybeomittedfromfuturepublicationsof thisreport. BioretentionInfeasibilitycriteria Thefollowingcriteriadescribeconditionsthatmakebioretentionorraingardensnotrequired. IfaprojectproponentwishestouseabioretentionorraingardenBMPthoughnotrequiredto becauseofthesefeasibilitycriteria,theymayproposeafunctionaldesigntothelocal government.Note:Criteriawithsetbackdistancesareasmeasuredfromtheedgeofthe bioretentionsoilmix. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 10 Citationofanyofthefollowinginfeasibilitycriteriamustbebasedonanevaluationofsite specificconditionsandawrittenrecommendationfromanappropriatelicensedprofessional (e.g.,engineer,geologist,hydrogeologist): Whereprofessionalgeotechnicalevaluationrecommendsinfiltrationnotbeuseddue toreasonableconcernsabouterosion,slopefailure,ordowngradientflooding. Noissue.Geotechsupportstheuseofinfiltration. Withinanareawhosegroundwaterdrainsintoanerosionhazard,orlandslidehazard area. Noissue. Wheretheonlyareaavailableforsitingwouldthreatenthesafetyorreliabilityofpre existingundergroundutilities,preexistingundergroundstoragetanks,preexisting structures,orpreexistingroadorparkinglotsurfaces. Noissue. Wheretheonlyareaavailableforsitingdoesnotallowforasafeoverflowpathwayto themunicipalseparatestormsewersystemorprivatestormsewersystem. Anoverflowisprovidedthatconnectstoanexistingdischarge. Wherethereisalackofusablespaceforraingarden/bioretentionfacilitiesatre developmentsites,orwherethereisinsufficientspacewithintheexistingpublicrightof wayonpublicroadprojects. Noissue. Whereinfiltratingwaterwouldthreatenexistingbelowgradebasements. bƚƉƓƚǞƓźƭƭǒĻ͵ Whereinfiltratingwaterwouldthreatenshorelinestructuressuchasbulkheads. Noissue. Thefollowingcriteriacanbecitedasreasonsforafindingofinfeasibilitywithoutfurther justification(thoughsomerequireprofessionalservices): Withinsetbacksfromstructuresasestablishedbythelocalgovernmentwith jurisdiction. Thereisadequateclearance. Wheretheyarenotcompatiblewithsurroundingdrainagesystemasdeterminedby thelocalgovernmentwithjurisdiction(e.g.,projectdrainstoanexistingstormwater collectionsystemwhoseelevationorlocationprecludesconnectiontoaproperly functioningbioretentionfacility). Notanissue. Wherelandforbioretentioniswithinareadesignatedasanerosionhazard,or landslidehazard. Notanissue. Wherethesitecannotbereasonablydesignedtolocatebioretentionfacilitieson slopeslessthan8%. bƚƷğƓźƭƭǒĻ͵ Within50feetfromthetopofslopesthataregreaterthan20%andover10feetof verticalrelief. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 11 Therearemanmadeslopeswithin50feetbutnonaturalslopesthatmeetthatcriteria forsteepnessorforheight. Forpropertieswithknownsoilorgroundwatercontamination(typicallyfederal SuperfundsitesorstatecleanupsitesundertheModelToxicsControlAct(MTCA)): oWithin100feetofanareaknowntohavedeepsoilcontamination; oWheregroundwatermodelingindicatesinfiltrationwilllikelyincreaseorchangethe directionofthemigrationofpollutantsinthegroundwater; oWhereversurfacesoilshavebeenfoundtobecontaminatedunlessthosesoilsare removedwithin10horizontalfeetfromtheinfiltrationarea; oAnyareawherethesefacilitiesareprohibitedbyanapprovedcleanupplanunderthe stateModelToxicsControlActorFederalSuperfundLaw,oranenvironmentalcovenant underChapter64.70RCW. Noissue. Within100feetofaclosedoractivelandfill. Doesnotapply. Within100feetofadrinkingwaterwell,oraspringusedfordrinkingwatersupply. Nowellswithin100feet. Within10feetofsmallonsitesewagedisposaldrainfield,includingreserveareas,and greywaterreusesystems.ForsetbacksfromaͻƌğƩŭĻonsitesewagedisposalƭǤƭƷĻƒͲͼsee Chapter246272BWAC. Noissue. Within10feetofanundergroundstoragetankandconnectingundergroundpipes whenthecapacityofthetankandpipesystemis1100gallonsorless.(Asusedinthese criteria,anundergroundstoragetankmeansanytankusedtostorepetroleumproducts, chemicals,orliquidhazardouswastesofwhich10%ormoreofthestoragevolume (includingvolumeintheconnectingpipingsystem)isbeneaththegroundsurface. Notanissue. Within100feetofanundergroundstoragetankandconnectingundergroundpipes whenthecapacityofthetankandpipesystemisgreaterthan1100gallons. Notanissue. Wheretheminimumverticalseparationof1foottotheseasonalhighwatertable, bedrock,orotherimperviouslayerwouldnotbeachievedbelowbioretentionorrain sq.ft.ofpollution gardensthatwouldserveadrainageareathatis:1)lessthan5,000 generatingimpervioussurface,and2)lessthan10,000sq.ft.ofimpervioussurface;and,3) lessthan¾acresofpervioussurface. N/A Wheretheaminimumverticalseparationof3feettotheseasonalhighwatertable, bedrockorotherimperviouslayerwouldnotbeachievedbelowbioretentionthat:1)would serveadrainageareathatmeetsorexceeds:a)5,000squarefeetofpollutiongenerating impervioussurface,orb)10,000squarefeetofimpervioussurface,orc)threequarter(3/4) acresofpervioussurfaces;and2)cannotreasonablybebrokendownintoamountssmaller thanindicatedin(1). BasedonareviewofthegeotechnicalreportthereismorethanА͵Ў͸togroundwater. * P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 12 Wherethefieldtestingindicatespotentialbioretention/raingardensiteshavea measured(a.k.a.,initial)nativesoilsaturatedhydraulicconductivitylessthan0.30inches perhour.Ifthemeasurednativesoilinfiltrationrateislessthan0.30in/hour,thisoption shouldnotbeusedtomeettherequirementsofMR#5.Intheseslowdrainingsoils,a bioretentionfacilitywithanunderdrainmaybeusedtotreatpollutiongeneratingsurfaces tohelpmeetMinimumRequirement#6,RunoffTreatment.Iftheunderdrainiselevated withinabasecourseofgravel,thebioretentionsystemwillalsoprovidesomemodestflow reductionbenefitthatwillhelpachieveMinimumRequirement#7. Notanissue.Geotechsupportsinfiltrationratesof2inlhr,theWWHM12calculations wereconductedwith2in/hr. Othersitesuitabilityfactors Utilityconflicts:ConsultSnohomishCountyrequirementsforhorizontalandverticalseparation requiredforpubliclyownedutilities,suchaswaterandsewer.Consulttheappropriate franchiseutilityownersforseparationrequirementsfromtheirutilities,whichmayinclude communicationsandgas.Whenseparationrequirementscannotbemet,designsshould includeappropriatemitigationmeasures,suchasimpermeablelinersovertheutility,sleeving utilities,fixingknownleakyjointsorcrackedconduits,and/oraddinganunderdraintothe bioretention. Noissue. Transportationsafety:Thedesignconfigurationandselectedplanttypesshouldprovide adequatesightdistances,clearzones,andappropriatesetbacksforroadwayapplicationsin accordancewithSnohomishCountyrequirements. Noissue. Pondingdepthandsurfacewaterdrawdown:Flowcontrolneeds,aswellaslocationinthe development,andmosquitobreedingcycleswilldeterminedrawdowntiming.Forexample, frontyardsandentrancestoresidentialorcommercialdevelopmentsmayrequirerapidsurface dewateringforaesthetics. Noissue. Impactsofsurroundingactivities:Humanactivityinfluencesthelocationofthefacilityinthe development.Forexample,locatebioretentionareasawayfromtraveledareasonindividual lotstopreventsoilcompactionanddamagetovegetationorprovideelevatedorbermed pathwaysinareaswherefoottrafficisinevitable.Providebarriers,suchaswheelstops,to restrictvehicleaccessinroadsideapplications. Curbing,wheelstopsandseparationwillprotectthefacilities. Visualbuffering:Bioretentionfacilitiescanbeusedtobufferstructuresfromroads,enhance privacyamongresidences,andforanaestheticsitefeature. N/A. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 13 Sitegrowingcharacteristicsandplantselection:Appropriateplantsshouldbeselectedforsun exposure,soilmoisture,andadjacentplantcommunities.Nativespeciesorhardycultivarsare recommendedandcanflourishintheproperlydesignedandplacedBioretentionSoilMixwith nonutrientorpesticideinputsand23yearsirrigationforestablishment.Invasivespecies controlmaybenecessary. Thelandscapingwillselectappropriateplantingsforthesiteconditions. BIORETENTIONCELLDESIGN Theunderlyingsoilsaresandygravel.PerGeotest,thelongtermsinfiltrationratemeetsor exceedsЋͻΉŷƩwhichexceedsthatofthepercolationrateoftheamendedsoilandunderdrains arenotneeded.DĻƚƷĻƭƷ͸ƭsoillogsshowthatnogroundwater,orevidenceofgroundwaterwas observedinanyoftheexplorationpitswhichrangeddeeperthanА͵Ў͸͵Thebioretentioncell floorisapproximately7.5ftabovetheshallowesttestpitinthatvicinity. The\[ƚǞLƒƦğĭƷ5ĻǝĻƌƚƦƒĻƓƷĻĭŷƓźĭğƌDǒźķğƓĭĻağƓǒğƌŅƚƩtǒŭĻƷ{ƚǒƓķ wasreferencedto designthespecificfacilitiesforthissite.Thefollowingitemsarecommonforallbioretention cells: Sideslopes(retained)0.1:1 AmendedSoilDepthЊБͼ AmendedSoilInfiltrationRateЋ͵ЉͼΉŷƩ MaximumSurfaceStorageDepthЊБͼ SubdrainageNativesoilexceedsЋͼΉŷƩͲnoadditionalmaterial addedforstorage. Theamendedsoilswillhelpsupportplantandmicrobialgrowthandprovideadditional stormwaterstoragecapacitywithadesignedvoidsratioof40%asrecommendedbythedesign manuals.Tomeettreatmentrequirements,anexcessof91%oftherunoffmustfilterthrough theamendedsoils.100%oftherunofftothebiocellpassesthroughthemedia,100%ofthe flowisinfiltrated. TREATMENTFACILITYSUMMARY Therebioretentioncellprovidestreatmentandinfiltrationoftheparkingandvehicular circulationroutes,includingasmallamountofrunofffrom228th. ContributingArea(SF)Required5%Area(SF)ProvidedArea(SF) BMPT7.30Biocell12,861643690 SeeattachedWWHM12screenshotsinAppendixBforsizingcalculations.With100percent filteredthroughtheamendedsoil,thesitemeetstreatmentrequirements. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc STORMWATER SITE PLAN April 11, 2017 WESTGATE WOODS PAGE 14 EMERGENCYOVERFLOW Anoverflowwillbeprovidedforthecellthatconnectstothepublicstormsystembeneath 9ķƒƚƓķ͸ƭWay.AType1catchbasinfittedwithatrashrackwillserveasaweirinletandan emergencyoverflow.Thisstructureisconveyedtothepublicstormsystemviaanexisting Type2locatedonthenearcurbofEdmondsWay.Theproposedstormwaterfacilitiesare expectedtoinfiltrate100%,nooverflowisexpected. MR7:FLOWCONTROL Runofffromthesiteis100%infiltratedviathecombinedeffortsofaBMPTT.30Bioretention CellandBMPT5.10ADownspoutInfiltration.NoadditionalFlowControlisnecessary,see discussioninprevioussectionofreport. MR8:WETLANDSPROTECTION Therearenowetlandsonornearthesitetoprotect. MR9:BASIN/WATERSHEDPLANNING Thissiteachieves100%infiltrationonsite.Nobasinorwatershedsareimpacted.Additional basinorwatershedplanningisnotnecessary. MR10:OPERATIONANDMAINTENANCE AnOperationsandMaintenanceManualshallbeprovidedunderseparatecoverwiththe Constructionplansanddrainagemanual. P:\\Work (Sharefile)\\Projects\\2016\\16-241 Westgate\\CE\\DOCS\\Drain\\2017 04 11 16-241 Westgate Drainage Report.doc RECEIVED 05/11/2017 Development Services Ctr. City of Edmonds 2012/2014DOEFlowChart FIGURES&BASINMAPS Start Here Yes Does the site have 35%See Redevelopment Minimum or more of existing Requirements and Flow Chart impervious coverage? (Figure I-2.4.2). No 3 Does the project convert 4 acres or more of vegetation to lawn or landscaped areas, or Does the project result in No convert 2.5 acres or more of 5,000 square feet, or native vegetation to pasture? greater, of new plus replaced hard surface area? No Yes Yes Does the project result in 2,000 square feet, or greater, of new plus replaced hard surface area? All Minimum Requirements apply to the new and replaced hard surfaces and converted No Yes vegetation areas. Does the project have land disturbing activities of 7,000 Minimum Requirements #1 square feet or greater? through #5 apply to the new Yes and replaced hard surfaces and the land disturbed. No Minimum Requirement #2 applies. Figure I-2.4.1 Flow Chart for Determining Requirements for New Development DEPARTMENTOF Revised June 2015 ECOLOGY http://www.ecy.wa.gov/copyright.html Please see for copyright notice including permissions, limitation of liability, and disclaimer. StateofWashington FIGURE3:DEVELOPEDSITEMAP NottoScale APPENDIXA WWHM12SCREENSHOTS SITELOCATION PREDEVELOPEDBASIN DEVELOPEDBASINS INFILTRATINGBIOCELL APPENDIXB GEOTECHREPORT RECEIVED 05/11/2017 Development Services Ctr. City of Edmonds WWHM2012 PROJECT REPORT General Model Information Project Name:16-241 Westgate Site Name:Westgate Woods Site Address:9511 Edmonds Way City:Edmonds Report Date:4/10/2017 Gage:Everett Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:0.800 Version Date:2016/11/18 Version:4.2.13 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year 16-241 Westgate4/10/2017 5:08:04 PMPage 2 Landuse Basin Data Predeveloped Land Use Existing+ Frontage Bypass:No GroundWater:No Pervious Land Useacre A B, Forest, Flat0.561 A B, Forest, Steep0.058 Pervious Total0.619 Impervious Land Useacre Impervious Total0 Basin Total0.619 Element Flows To: SurfaceInterflowGroundwater 16-241 Westgate4/10/2017 5:08:04 PMPage 3 Mitigated Land Use Developed Bypass:No GroundWater:No Pervious Land Useacre A B, Pasture, Flat0.328 Pervious Total0.328 Impervious Land Useacre ROADS FLAT0.015 ROOF TOPS FLAT0.093 DRIVEWAYS FLAT0.183 Impervious Total0.291 Basin Total0.619 Element Flows To: SurfaceInterflowGroundwater Surface Biocell 1Surface Biocell 1 16-241 Westgate4/10/2017 5:08:04 PMPage 4 Routing Elements Predeveloped Routing 16-241 Westgate4/10/2017 5:08:04 PMPage 5 Mitigated Routing Biocell 1 Bottom Length: 70.00 ft. Bottom Width: 9.90 ft. Material thickness of first layer: 1.5 Material type for first layer: SMMWW 12 in/hr Material thickness of second layer: 0 Material type for second layer: Sand Material thickness of third layer: 0 Material type for third layer: GRAVEL Infiltration On Infiltration rate:2 Infiltration safety factor:1 Total Volume Infiltrated (ac-ft.):35.359 Total Volume Through Riser (ac-ft.):0 Total Volume Through Facility (ac-ft.):35.359 Percent Infiltrated:100 Total Precip Applied to Facility:2.119 Total Evap From Facility:1.02 Underdrain not used Discharge Structure Riser Height:1.5 ft. Riser Diameter:12 in. Element Flows To: Outlet 1Outlet 2 Bioretention Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.00000.01650.00000.00000.0000 0.04400.01650.00020.00000.0000 0.08790.01640.00030.00000.0001 0.13190.01640.00050.00000.0001 0.17580.01640.00060.00000.0002 0.21980.01640.00080.00000.0004 0.26370.01640.00100.00000.0007 0.30770.01640.00110.00000.0010 0.35160.01630.00130.00000.0013 0.39560.01630.00140.00000.0018 0.43960.01630.00160.00000.0023 0.48350.01630.00180.00000.0029 0.52750.01630.00190.00000.0036 0.57140.01630.00210.00000.0044 0.61540.01620.00230.00000.0053 0.65930.01620.00240.00000.0062 0.70330.01620.00270.00000.0073 0.74730.01620.00310.00000.0085 0.79120.01620.00340.00000.0098 0.83520.01620.00370.00000.0112 0.87910.01620.00400.00000.0127 0.92310.01610.00440.00000.0144 0.96700.01610.00470.00000.0161 1.01100.01610.00500.00000.0180 1.05490.01610.00540.00000.0201 1.09890.01610.00570.00000.0222 16-241 Westgate4/10/2017 5:08:04 PMPage 6 1.14290.01610.00600.00000.0245 1.18680.01600.00630.00000.0269 1.23080.01600.00670.00000.0294 1.27470.01600.00700.00000.0321 1.31870.01600.00730.00000.0321 1.36260.01600.00770.00000.0321 1.40660.01600.00800.00000.0321 1.45050.01590.00830.00000.0321 1.49450.01590.00860.00000.0321 1.50000.01590.00870.00000.0321 Bioretention Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)To Amended(cfs)Infilt(cfs) 1.50000.01650.00870.00000.1981 0.0000 1.54400.01650.00940.00000.1981 0.0000 1.58790.01650.01010.00000.2038 0.0000 1.63190.01650.01090.00000.2094 0.0000 1.67580.01650.01160.00000.2151 0.0000 1.71980.01650.01230.00000.2207 0.0000 1.76370.01660.01300.00000.2263 0.0000 1.80770.01660.01380.00000.2320 0.0000 1.85160.01660.01450.00000.2376 0.0000 1.89560.01660.01520.00000.2433 0.0000 1.93960.01660.01600.00000.2489 0.0000 1.98350.01660.01670.00000.2546 0.0000 2.02750.01670.01740.00000.2602 0.0000 2.07140.01670.01820.00000.2658 0.0000 2.11540.01670.01890.00000.2715 0.0000 2.15930.01670.01960.00000.2771 0.0000 2.20330.01670.02040.00000.2828 0.0000 2.24730.01670.02110.00000.2884 0.0000 2.29120.01680.02180.00000.2940 0.0000 2.33520.01680.02260.00000.2997 0.0000 2.37910.01680.02330.00000.3053 0.0000 2.42310.01680.02400.00000.3110 0.0000 2.46700.01680.02480.00000.3166 0.0000 2.51100.01680.02550.00000.3222 0.0000 2.55490.01690.02630.00000.3279 0.0000 2.59890.01690.02700.00000.3335 0.0000 2.64290.01690.02770.00000.3392 0.0000 2.68680.01690.02850.00000.3448 0.0000 2.73080.01690.02920.00000.3504 0.0000 2.77470.01690.03000.00000.3561 0.0000 2.81870.01700.03070.00000.3617 0.0000 2.86260.01700.03150.00000.3674 0.0000 2.90660.01700.03220.00000.3730 0.0000 2.95050.01700.03300.00000.3787 0.0000 2.99450.01700.03370.00000.3843 0.0000 3.03850.01700.03440.08000.3899 0.0000 3.08240.01700.03520.25010.3956 0.0000 3.12640.01710.03590.47120.4012 0.0000 3.17030.01710.03670.72550.4069 0.0000 3.21430.01710.03740.99660.4125 0.0000 3.25820.01710.03821.26760.4181 0.0000 3.30220.01710.03901.52170.4238 0.0000 3.34620.01710.03971.74450.4294 0.0000 3.39010.01720.04051.92550.4351 0.0000 3.43410.01720.04122.06200.4407 0.0000 16-241 Westgate4/10/2017 5:08:04 PMPage 7 3.47800.01720.04202.16140.4463 0.0000 3.52200.01720.04272.27550.4520 0.0000 3.56590.01720.04352.36940.4576 0.0000 3.60990.01720.04422.45970.4633 0.0000 3.65380.01730.04502.54680.4689 0.0000 3.69780.01730.04582.63100.4746 0.0000 3.74180.01730.04652.71260.4802 0.0000 3.78570.01730.04732.79180.4858 0.0000 3.82970.01730.04802.86890.4915 0.0000 3.87360.01730.04882.94390.4971 0.0000 3.91760.01740.04963.01700.5028 0.0000 3.96150.01740.05033.08850.5084 0.0000 4.00000.01740.05103.15830.5133 0.0000 16-241 Westgate4/10/2017 5:08:04 PMPage 8 Surface Biocell 1 Element Flows To: Outlet 1Outlet 2 Biocell 1 16-241 Westgate4/10/2017 5:08:04 PMPage 9 Analysis Results POC 1 + Predevelopedx Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.619 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:0.328 Total Impervious Area:0.291 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return PeriodFlow(cfs) 2 year0.000436 5 year0.000505 10 year0.000536 25 year0.000564 50 year0.000579 100 year0.000591 Flow Frequency Return Periods for Mitigated. POC #1 Return PeriodFlow(cfs) 2 year0 5 year0 10 year0 25 year0 50 year0 100 year0 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 YearPredevelopedMitigated 19490.0000.000 19500.0000.000 19510.0000.000 19520.0000.000 19530.0000.000 19540.0000.000 19550.0000.000 19560.0000.000 19570.0000.000 19580.0000.000 16-241 Westgate4/10/2017 5:08:04 PMPage 10 19590.0000.000 19600.0000.000 19610.0000.000 19620.0000.000 19630.0000.000 19640.0000.000 19650.0000.000 19660.0000.000 19670.0000.000 19680.0000.000 19690.0000.000 19700.0000.000 19710.0000.000 19720.0000.000 19730.0000.000 19740.0000.000 19750.0000.000 19760.0000.000 19770.0000.000 19780.0000.000 19790.0000.000 19800.0000.000 19810.0000.000 19820.0000.000 19830.0000.000 19840.0000.000 19850.0000.000 19860.0000.000 19870.0000.000 19880.0000.000 19890.0000.000 19900.0000.000 19910.0000.000 19920.0000.000 19930.0000.000 19940.0000.000 19950.0000.000 19960.0000.000 19970.0000.000 19980.0000.000 19990.0000.000 20000.0000.000 20010.0000.000 20020.0000.000 20030.0000.000 20040.0000.000 20050.0000.000 20060.0000.000 20070.0000.000 20080.0000.000 20090.0000.000 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 RankPredevelopedMitigated 10.00050.0000 20.00050.0000 30.00050.0000 16-241 Westgate4/10/2017 5:16:04 PMPage 11 40.00050.0000 50.00050.0000 60.00050.0000 70.00050.0000 80.00050.0000 90.00050.0000 100.00050.0000 110.00050.0000 120.00050.0000 130.00050.0000 140.00050.0000 150.00050.0000 160.00050.0000 170.00050.0000 180.00050.0000 190.00050.0000 200.00050.0000 210.00050.0000 220.00050.0000 230.00050.0000 240.00050.0000 250.00050.0000 260.00050.0000 270.00050.0000 280.00050.0000 290.00050.0000 300.00040.0000 310.00040.0000 320.00040.0000 330.00040.0000 340.00040.0000 350.00040.0000 360.00040.0000 370.00040.0000 380.00040.0000 390.00040.0000 400.00040.0000 410.00040.0000 420.00040.0000 430.00040.0000 440.00040.0000 450.00040.0000 460.00040.0000 470.00040.0000 480.00040.0000 490.00040.0000 500.00040.0000 510.00040.0000 520.00040.0000 530.00040.0000 540.00040.0000 550.00030.0000 560.00030.0000 570.00030.0000 580.00030.0000 590.00030.0000 600.00030.0000 610.00010.0000 16-241 Westgate4/10/2017 5:16:04 PMPage 12 16-241 Westgate4/10/2017 5:16:04 PMPage 13 Duration Flows The Facility PASSED Flow(cfs)PredevMitPercentagePass/Fail 0.000288300Pass 0.000286900Pass 0.000283800Pass 0.000281400Pass 0.000277900Pass 0.000275700Pass 0.000273700Pass 0.000270800Pass 0.000268100Pass 0.000366000Pass 0.000363200Pass 0.000360100Pass 0.000358400Pass 0.000356700Pass 0.000354600Pass 0.000352400Pass 0.000350200Pass 0.000348700Pass 0.000346600Pass 0.000344400Pass 0.000343000Pass 0.000340600Pass 0.000339000Pass 0.000338200Pass 0.000336400Pass 0.000335300Pass 0.000334500Pass 0.000333200Pass 0.000331700Pass 0.000330900Pass 0.000329800Pass 0.000328300Pass 0.000327300Pass 0.000325900Pass 0.000324800Pass 0.000324100Pass 0.000322900Pass 0.000422300Pass 0.000421400Pass 0.000420800Pass 0.000420100Pass 0.000419400Pass 0.000418500Pass 0.000418300Pass 0.000417300Pass 0.000417100Pass 0.000416300Pass 0.000415600Pass 0.000414900Pass 0.000414300Pass 0.000413900Pass 0.000413400Pass 0.000412200Pass 16-241 Westgate4/10/2017 5:16:04 PMPage 14 0.000411900Pass 0.000411300Pass 0.000410700Pass 0.000410100Pass 0.00049800Pass 0.00048900Pass 0.00048500Pass 0.00047900Pass 0.00047200Pass 0.00046500Pass 0.00046100Pass 0.00055700Pass 0.00055100Pass 0.00054900Pass 0.00054200Pass 0.00053900Pass 0.00053500Pass 0.00053100Pass 0.00052900Pass 0.00052100Pass 0.00051500Pass 0.00051400Pass 0.0005900Pass 0.0005100Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0005000Pass 0.0006000Pass 0.0006000Pass 0.0006000Pass 0.0006000Pass 0.0006000Pass 0.0006000Pass 0.0006000Pass 0.0006000Pass 16-241 Westgate4/10/2017 5:16:04 PMPage 15 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. 16-241 Westgate4/10/2017 5:16:04 PMPage 16 LID Report 16-241 Westgate4/10/2017 5:16:04 PMPage 17 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. 16-241 Westgate4/10/2017 5:16:24 PMPage 18 Appendix Predeveloped Schematic 16-241 Westgate4/10/2017 5:16:24 PMPage 19 Mitigated Schematic 16-241 Westgate4/10/2017 5:16:24 PMPage 20 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 16-241 Westgate.wdm MESSU 25 Pre16-241 Westgate.MES 27 Pre16-241 Westgate.L61 28 Pre16-241 Westgate.L62 30 POC16-241 Westgate1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 1 PERLND 3 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Existing+ Frontage MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 1 A/B, Forest, Flat 1 1 1 1 27 0 3 A/B, Forest, Steep 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 1 0 0 1 0 0 0 0 0 0 0 0 0 3 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 16-241 Westgate4/10/2017 5:16:24 PMPage 21 1 0 0 4 0 0 0 0 0 0 0 0 0 1 9 3 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 1 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 1 0 5 2 400 0.05 0.3 0.996 3 0 5 2 400 0.15 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 1 0 0 2 2 0 0 0 3 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 1 0.2 0.5 0.35 0 0.7 0.7 3 0.2 0.5 0.35 0 0.7 0.7 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 1 0 0 0 0 3 1 0 3 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC END IWAT-PARM2 IWAT-PARM3 16-241 Westgate4/10/2017 5:16:24 PMPage 22 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Existing+ Frontage*** PERLND 1 0.561 COPY 501 12 PERLND 1 0.561 COPY 501 13 PERLND 3 0.058 COPY 501 12 PERLND 3 0.058 COPY 501 13 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES 16-241 Westgate4/10/2017 5:16:24 PMPage 23 SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 0.8 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 0.8 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 501 OUTPUT MEAN 1 1 48.4 WDM 501 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 END MASS-LINK END RUN 16-241 Westgate4/10/2017 5:16:24 PMPage 24 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 16-241 Westgate.wdm MESSU 25 Mit16-241 Westgate.MES 27 Mit16-241 Westgate.L61 28 Mit16-241 Westgate.L62 30 POC16-241 Westgate1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 4 IMPLND 1 IMPLND 4 IMPLND 5 GENER 2 RCHRES 1 RCHRES 2 COPY 1 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Surface Biocell 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** 2 24 END OPCODE PARM # # K *** 2 0. END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 4 A/B, Pasture, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 16-241 Westgate4/10/2017 5:16:24 PMPage 25 4 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 4 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 4 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 4 0 5 1.5 400 0.05 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 4 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 4 0.15 0.5 0.3 0 0.7 0.4 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 4 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 1 ROADS/FLAT 1 1 1 27 0 4 ROOF TOPS/FLAT 1 1 1 27 0 5 DRIVEWAYS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 1 0 0 1 0 0 0 4 0 0 1 0 0 0 5 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 1 0 0 4 0 0 0 1 9 4 0 0 4 0 0 0 1 9 5 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** 16-241 Westgate4/10/2017 5:16:24 PMPage 26 # - # CSNO RTOP VRS VNN RTLI *** 1 0 0 0 0 0 4 0 0 0 0 0 5 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 1 400 0.01 0.1 0.1 4 400 0.01 0.1 0.1 5 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 1 0 0 4 0 0 5 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 1 0 0 4 0 0 5 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Developed*** PERLND 4 0.328 RCHRES 1 2 PERLND 4 0.328 RCHRES 1 3 IMPLND 1 0.015 RCHRES 1 5 IMPLND 4 0.093 RCHRES 1 5 IMPLND 5 0.183 RCHRES 1 5 ******Routing****** PERLND 4 0.328 COPY 1 12 IMPLND 1 0.015 COPY 1 15 IMPLND 4 0.093 COPY 1 15 IMPLND 5 0.183 COPY 1 15 PERLND 4 0.328 COPY 1 13 RCHRES 1 1 RCHRES 2 8 RCHRES 2 1 COPY 501 17 RCHRES 1 1 COPY 501 17 END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 GENER 2 OUTPUT TIMSER .0011111 RCHRES 1 EXTNL OUTDGT 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** 16-241 Westgate4/10/2017 5:16:24 PMPage 27 1 Surface Biocell -007 3 1 1 1 28 0 1 2 Biocell 1 2 1 1 1 28 0 1 END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** 1 1 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* 1 4 0 0 0 0 0 0 0 0 0 1 9 2 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** 1 0 1 0 0 4 5 6 0 0 0 1 0 0 0 2 1 2 2 2 2 0 1 0 0 4 5 0 0 0 0 0 0 0 0 2 2 2 2 2 END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** 1 1 0.01 0.0 0.0 0.5 0.0 2 2 0.01 0.0 0.0 0.5 0.0 END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> 1 0 4.0 5.0 6.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2 0 4.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 END HYDR-INIT END RCHRES SPEC-ACTIONS *** User-Defined Variable Quantity Lines *** addr *** <------> *** kwd varnam optyp opn vari s1 s2 s3 tp multiply lc ls ac as agfn *** <****> <----> <----> <-> <----><-><-><-><-><--------> <><-> <><-> <--> *** UVQUAN vol2 RCHRES 2 VOL 4 UVQUAN v2m2 GLOBAL WORKSP 1 3 UVQUAN vpo2 GLOBAL WORKSP 2 3 UVQUAN v2d2 GENER 2 K 1 3 *** User-Defined Target Variable Names *** addr or addr or *** <------> <------> *** kwd varnam ct vari s1 s2 s3 frac oper vari s1 s2 s3 frac oper <****> <----><-> <----><-><-><-> <---> <--> <----><-><-><-> <---> <--> UVNAME v2m2 1 WORKSP 1 1.0 QUAN UVNAME vpo2 1 WORKSP 2 1.0 QUAN UVNAME v2d2 1 K 1 1.0 QUAN *** opt foplop dcdts yr mo dy hr mn d t vnam s1 s2 s3 ac quantity tc ts rp <****><-><--><><-><--> <> <> <> <><><> <----><-><-><-><-><--------> <> <-><-> GENER 2 v2m2 = 357. *** Compute remaining available pore space GENER 2 vpo2 = v2m2 GENER 2 vpo2 -= vol2 *** Check to see if VPORA goes negative; if so set VPORA = 0.0 IF (vpo2 < 0.0) THEN 16-241 Westgate4/10/2017 5:16:24 PMPage 28 GENER 2 vpo2 = 0.0 END IF *** Infiltration volume GENER 2 v2d2 = vpo2 END SPEC-ACTIONS FTABLES FTABLE 2 36 5 Depth Area Volume Outflow1 Outflow2 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.016461 0.000000 0.000000 0.000000 0.043956 0.016459 0.000160 0.000000 0.000013 0.087912 0.016443 0.000320 0.000000 0.000052 0.131868 0.016427 0.000480 0.000000 0.000127 0.175824 0.016411 0.000641 0.000000 0.000249 0.219780 0.016394 0.000802 0.000000 0.000423 0.263736 0.016378 0.000962 0.000000 0.000656 0.307692 0.016362 0.001123 0.000000 0.000954 0.351648 0.016346 0.001284 0.000000 0.001322 0.395604 0.016330 0.001446 0.000000 0.001765 0.439560 0.016313 0.001607 0.000000 0.002287 0.483516 0.016297 0.001769 0.000000 0.002893 0.527473 0.016281 0.001930 0.000000 0.003587 0.571429 0.016265 0.002092 0.000000 0.004373 0.615385 0.016249 0.002254 0.000000 0.005253 0.659341 0.016232 0.002417 0.000000 0.006234 0.703297 0.016216 0.002742 0.000000 0.007316 0.747253 0.016200 0.003067 0.000000 0.008505 0.791209 0.016184 0.003392 0.000000 0.009802 0.835165 0.016168 0.003718 0.000000 0.011212 0.879121 0.016151 0.004044 0.000000 0.012737 0.923077 0.016135 0.004370 0.000000 0.014381 0.967033 0.016119 0.004697 0.000000 0.016146 1.010989 0.016103 0.005024 0.000000 0.018034 1.054945 0.016087 0.005352 0.000000 0.020050 1.098901 0.016071 0.005680 0.000000 0.022195 1.142857 0.016054 0.006008 0.000000 0.024473 1.186813 0.016038 0.006336 0.000000 0.026885 1.230769 0.016022 0.006665 0.000000 0.029434 1.274725 0.016006 0.006994 0.000000 0.032083 1.318681 0.015990 0.007323 0.000000 0.032083 1.362637 0.015974 0.007653 0.000000 0.032083 1.406593 0.015957 0.007983 0.000000 0.032083 1.450549 0.015941 0.008313 0.000000 0.032083 1.494505 0.015925 0.008644 0.000000 0.032083 1.500000 0.015909 0.018239 0.000000 0.032083 END FTABLE 2 FTABLE 1 58 6 Depth Area Volume Outflow1 Outflow2 outflow 3 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.015909 0.000000 0.000000 0.000000 0.000000 0.043956 0.016478 0.000724 0.000000 0.198141 0.000000 0.087912 0.016494 0.001449 0.000000 0.203782 0.000000 0.131868 0.016510 0.002174 0.000000 0.209423 0.000000 0.175824 0.016526 0.002900 0.000000 0.215064 0.000000 0.219780 0.016543 0.003627 0.000000 0.220705 0.000000 0.263736 0.016559 0.004354 0.000000 0.226346 0.000000 0.307692 0.016575 0.005083 0.000000 0.231987 0.000000 0.351648 0.016592 0.005812 0.000000 0.237628 0.000000 0.395604 0.016608 0.006541 0.000000 0.243269 0.000000 0.439560 0.016624 0.007272 0.000000 0.248910 0.000000 0.483516 0.016640 0.008003 0.000000 0.254551 0.000000 0.527473 0.016657 0.008734 0.000000 0.260193 0.000000 0.571429 0.016673 0.009467 0.000000 0.265834 0.000000 0.615385 0.016689 0.010200 0.000000 0.271475 0.000000 0.659341 0.016706 0.010934 0.000000 0.277116 0.000000 0.703297 0.016722 0.011669 0.000000 0.282757 0.000000 16-241 Westgate4/10/2017 5:16:24 PMPage 29 0.747253 0.016738 0.012404 0.000000 0.288398 0.000000 0.791209 0.016754 0.013140 0.000000 0.294039 0.000000 0.835165 0.016771 0.013877 0.000000 0.299680 0.000000 0.879121 0.016787 0.014615 0.000000 0.305321 0.000000 0.923077 0.016803 0.015353 0.000000 0.310962 0.000000 0.967033 0.016820 0.016092 0.000000 0.316603 0.000000 1.010989 0.016836 0.016832 0.000000 0.322244 0.000000 1.054945 0.016852 0.017572 0.000000 0.327885 0.000000 1.098901 0.016869 0.018313 0.000000 0.333526 0.000000 1.142857 0.016885 0.019055 0.000000 0.339167 0.000000 1.186813 0.016901 0.019797 0.000000 0.344808 0.000000 1.230769 0.016918 0.020541 0.000000 0.350449 0.000000 1.274725 0.016934 0.021285 0.000000 0.356090 0.000000 1.318681 0.016950 0.022029 0.000000 0.361731 0.000000 1.362637 0.016967 0.022775 0.000000 0.367372 0.000000 1.406593 0.016983 0.023521 0.000000 0.373013 0.000000 1.450549 0.016999 0.024268 0.000000 0.378654 0.000000 1.494505 0.017016 0.025015 0.000000 0.384295 0.000000 1.538462 0.017032 0.025764 0.079976 0.389936 0.000000 1.582418 0.017049 0.026513 0.250137 0.395577 0.000000 1.626374 0.017065 0.027263 0.471194 0.401218 0.000000 1.670330 0.017081 0.028013 0.725495 0.406859 0.000000 1.714286 0.017098 0.028764 0.996598 0.412500 0.000000 1.758242 0.017114 0.029516 1.267570 0.418141 0.000000 1.802198 0.017131 0.030269 1.521742 0.423782 0.000000 1.846154 0.017147 0.031022 1.744468 0.429423 0.000000 1.890110 0.017163 0.031776 1.925525 0.435064 0.000000 1.934066 0.017180 0.032531 2.061968 0.440705 0.000000 1.978022 0.017196 0.033286 2.161385 0.446347 0.000000 2.021978 0.017213 0.034043 2.275546 0.451988 0.000000 2.065934 0.017229 0.034800 2.369422 0.457629 0.000000 2.109890 0.017245 0.035557 2.459718 0.463270 0.000000 2.153846 0.017262 0.036316 2.546815 0.468911 0.000000 2.197802 0.017278 0.037075 2.631029 0.474552 0.000000 2.241758 0.017295 0.037835 2.712631 0.480193 0.000000 2.285714 0.017311 0.038595 2.791849 0.485834 0.000000 2.329670 0.017327 0.039357 2.868880 0.491475 0.000000 2.373626 0.017344 0.040119 2.943896 0.497116 0.000000 2.417582 0.017360 0.040881 3.017047 0.502757 0.000000 2.461538 0.017377 0.041645 3.088466 0.508398 0.000000 2.500000 0.017391 0.042313 3.158271 0.513334 0.000000 END FTABLE 1 END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 0.8 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 0.8 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP WDM 2 PREC ENGL 0.8 RCHRES 1 EXTNL PREC WDM 1 EVAP ENGL 0.5 RCHRES 1 EXTNL POTEV WDM 1 EVAP ENGL 0.76 RCHRES 2 EXTNL POTEV END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** RCHRES 2 HYDR RO 1 1 1 WDM 1004 FLOW ENGL REPL RCHRES 2 HYDR O 1 1 1 WDM 1005 FLOW ENGL REPL RCHRES 2 HYDR O 2 1 1 WDM 1006 FLOW ENGL REPL RCHRES 2 HYDR STAGE 1 1 1 WDM 1007 STAG ENGL REPL RCHRES 1 HYDR STAGE 1 1 1 WDM 1008 STAG ENGL REPL RCHRES 1 HYDR O 1 1 1 WDM 1009 FLOW ENGL REPL COPY 1 OUTPUT MEAN 1 1 48.4 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 48.4 WDM 801 FLOW ENGL REPL END EXT TARGETS 16-241 Westgate4/10/2017 5:16:24 PMPage 30 MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 2 PERLND PWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 2 MASS-LINK 3 PERLND PWATER IFWO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 3 MASS-LINK 5 IMPLND IWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 5 MASS-LINK 8 RCHRES OFLOW OVOL 2 RCHRES INFLOW IVOL END MASS-LINK 8 MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 MASS-LINK 17 RCHRES OFLOW OVOL 1 COPY INPUT MEAN END MASS-LINK 17 END MASS-LINK END RUN 16-241 Westgate4/10/2017 5:16:24 PMPage 31 Predeveloped HSPF Message File 16-241 Westgate4/10/2017 5:16:24 PMPage 32 Mitigated HSPF Message File 16-241 Westgate4/10/2017 5:16:24 PMPage 33 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions Inc. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2017; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com 16-241 Westgate4/10/2017 5:16:24 PMPage 34 741 Marine Drive PHONE Bellingham, WA 98225 360 733_7318 th 20611-67Avenue NE FAX TOLL FREE 360 733_7418 Arlington, WA 98223 888 251_5276 RECEIVED June 10, 2016 Project No. 16-0234, REVISION 1 05/11/2017 Westgate Woods, LLC Development Services Ctr. C/O Bill Booth City of Edmonds th 2817 NW 94Street Seattle, Washington 98117 Re:Geotechnical Engineering Investigation Edmonds Townhouses 9511 Edmonds Way Edmonds, Washington Dear Mr. Booth: As requested, GeoTest Services, Inc. is pleased to submit this report summarizing the results of our geotechnical evaluation for the proposed Edmonds Townhouses Development, located at 9511 Edmonds Way in Edmonds, Washington.(see Vicinity Map, Figure 1). This report has been prepared in general accordance with the terms and conditions established in our services agreement, dated April 22, 2016. PROJECT DESCRIPTION The project site consists of two adjacent, moderately vegetated parcelsin an existing residential neighborhood. GTS anticipates that the properties will be cleared of native vegetation and that new construction will consist of multi-story townhomes utilizing wood-frame construction. GTS anticipates the use of shallow conventional foundations and slab-on-grade floors. GTS has not been provided structural loading, but we anticipate that structural loads will be relatively light. GTS anticipates minimal lot setbacks, reduced parking areas, and below-grade tanks or covered infiltration facilities to maximize the allowable area of development. GTS currently anticipates multiple units distributed across the property. GTS understands that the project site contains several feet of previously placed, uncontrolled fill materials. SITE CONDITIONS This section discusses the general surface and subsurface conditions observed at the project site during the time of our field investigation. Interpretations of the site conditions are based uponthe results of our review of available information, site reconnaissance, subsurface explorations, laboratory testing, and our experience in the project vicinity. Surface Conditions th The project site is bordered by Edmonds Way to the south, 95Place West along the eastern th property boundary, and 228Street SW along the northern property boundary. Regional topography consists of a large gully-like depression that drops to the west, with Edmonds Way following the center of this gullyand slopesrising to the north and south to either sideof the site. Page 1of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 The eastern half of thesubjectproperty is at or near the surrounding roadway grades, while the western half of the project site is approximately5 feet lower and generally depressedrelative to roadways to the northand southof the site.An approximately 5 foot high modular block retaining wall with railing separates the Edmonds Wayright-of-way from the property. GTS understands that historic grading activities may have lowered portions of thesite, possibly with the intent of removing sand and gravel from the site to be used as an exported material. Asidefrom the moderatlysteep 5 foot drop between the eastern and western portions of the property, thesite is relatively flat with less than a few feet of elevation differential. The west property shows indications of previous site development that include a concrete foundation. The previous structure has been largely removed from the site. Other indicators of previous site development remain, such as concrete foundation remnants, cleared areas of vegetation,and uncontrolled fill on the property. The site supports a moderate to dense growth of vegetation that consists of evergreen and deciduous trees, as well as typical forest undergrowth. GTS is aware that a drainagesystem was historically installed by the City along 228th Street SW with an outlet pipe draining onto the subject property without the previous property Owner's permission.GTS understands that the previous property Owner notified the City on or around 2010 of negative impacts to the propertyand that the drainage system was immediately removed,sealed,and/or decommissioned by the City. Since the removal of theCity’sdrainage systemover 5 years ago and property ownership being taken by the current Owner, GTS is not aware of surface drainage, wetland, or similar drainage-related issues being present on the site. Subsurface Soil Conditions Subsurface conditions were explored by advancing 5explorationtest pits (TP-1 though TP-5) onMay 6, 2016.The explorations were advanced to depths of between 7.5 and 10 feet below ground surface (BGS) using a subcontracted excavator. The approximate locations of the explorations are shown on the Site and Exploration Plan, Figure 2. The subsurface soils on the east half of the site generally consisted of a thin section of topsoil and/or forest duff, underlain by approximately 4 to 7 feet of previously placed, uncontrolled fill with variable amounts of cobbles, boulders, brick, concrete, and similar construction debris. Underlying the fill at depths of between 4.5 to 8 feet was native, medium dense to dense gravelly sand that was interpreted to be representative of Advance Outwash. On the west half of the site,GTS encountered a thin section of topsoil and/or forest duff underlain by loose, trending to dense,gravelly sand that was interpreted to be representative of Advance Outwash. See the attached Site and Exploration Map (Figure 2) and the Log of Test Pits (Figures 5 through 7) for more information regarding the approximate locations of the exploration pits and subsurface soil conditions encountered. General Geologic Conditions Geologic information for the project site was obtained from the “Geologic Map of the Edmonds East and part of the Edmonds West Quadrangles, Washington”(Minard, 1983), published by the United States Geological Survey. According to Minard, surficial soils in the vicinity of the project site consist of Advance Outwash (Qva), with Till (Qvt)in close proximity to the site.Till is recorded as being a more recent deposit and consisting of a non-sorted mixture of clay, silt, sand, pebbles, cobbles, and boulders. Till is a denseto very dense, glacially consolidated Page 2of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 material deposited directly by and overridden by glacial ice.Advance Outwash is mapped below the Till and is described as a mostly clean pebbly sand with increasing amounts of gravel higher in the section. The Advance Outwash was deposited by the meltwater before being overridden during the advance of the glacier. Advance Outwash is typically dense to very dense due to the glacial consolidation that it experienced. Subsurface soils encountered within the exploration test pitsweregenerally consistent with Advance Outwash. Groundwater At the time of our subsurface investigation in April of 2016, groundwater seepage was not observed in any of our explorations.The groundwater conditions reported on the exploration logs are for the specific locations and dates indicated, and therefore may not necessarily be indicative of other locations and/or times. Groundwater levels and/or seepage rates are not static and it is anticipated that groundwater conditions will vary depending on local subsurface conditions, season, precipitation, changes in land use both on and off site and other factors. The dense to very dense nature of the subsurface soils, combined with generally looser materials encountered in the upper 2 to 3 feet suggest that perched groundwater conditions may develop during extended periods of rainfall. Perched groundwater conditions are encountered when looser or more granular materials overlie denser or siltier materials, thus preventing groundwater seepage from adequately draining. CONCLUSIONS AND RECOMMENDATIONS It is our opinion that subsurface conditions at the site are suitable for the proposed improvements, provided the recommendations contained herein are incorporated into the project design Geologic Hazards and Recommended Mitigation The proposed area of improvement is relatively flat and underlain by dense to very dense, glacially consolidated materials. As such, the property does not meet the criteria established in the City of Edmonds Municipal Code for slope,seismic, or erosionhazards.These hazards include slope stability hazards, liquefaction hazards, and landslide hazards. The closest fault trace to the project site is the South Whidbey Island-Lake Alice Fault, but this fault is located severalmiles from the projected fault line and, historically, has not had indications of surficial ground rupture. As such, no specific mitigations for geologically hazardous areas or surficial ground rupture are required for this project. Site development is,however, anticipated to include a Washington State Department of Ecology Construction Storm Water General Permitto mitigate the erosion potential of soils exposed during construction or site grading activities. In order to meet the criteria established by the Department of Ecology, anerosion control plan consistent with the governing municipal standards and best management practices will be required for this project. The contractor will be responsible for implementing the erosion control planas established in the plans and specifications approved by the governing municipality for the project. Page 3of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 Site Preparation and Earthwork The portions of the site to be occupied by proposed foundation,floor slabs,and/orsidewalks should be prepared by removing any existing pavements, topsoil, existing fill, deleterious material and significant accumulations of organics from the area to be developed. Based on our subsurface soil explorations, GTS anticipates that up to 8 feet of Uncontrolled Fill will be removed on the east half of the site, and that about 1 to 1.5 feet of Uncontrolled Filland Topsoil will be removed on the west half of the site. Given the unknowns regarding how the fill was initially placed and the variable thicknessof fill across the site, GTS recommends that flexibility be built into contract documents regarding the removal of on-site Uncontrolled Fill from development areas. The thickness of the Uncontrolled Fill is not uniform and may be either shallower or deeper in other areas of the site than what was observed during our explorations. GTS recommends that we be present during stripping operations to document the depth of removed soils. Such documentation may become important in determining contractual reimbursement to the contractor and will be dependent upon how the contract is structured. Prior to placement of any foundation elements or structural fill, the exposed subgrade under all areas to be occupied by soil-supported floor slabsor new foundations should be recompacted to afirmand unyielding condition and proof rolled with a loaded dump truck, large self-propelled vibrating roller, or similarpiece of equipment applicable to the size of the excavation. The purpose of this effort is to identify possible loose or soft soil deposits and recompact, if feasible, the soil disturbed during site excavation activities. Proof rolling should be observed by qualified geotechnical personnel. Areas exhibiting significant deflection, pumping, or observed to have elevated moisture contents that prevent the soil from being adequately compacted should be overexcavated to firm soil. Overexcavated areas should be backfilled with structural fill as recommended elsewhere in this report. During periods of wet weather, proof rolling could damage the exposed subgrade. Under these conditions, qualified geotechnical personnel should observe subgrade conditions to determine if proof rolling is feasible. Fill and Compaction Structural fill used to obtain final elevations for footings, soil-supported floor slabs, and/or sidewalksmust be properly placed and compacted. In general, non-organic, predominantly granular soil may be used as structural fill provided the material is properly moisture conditioned prior to placement and compacted to at least 95 percent of the maximum dry density, as determined using test method ASTM D1557. Material containing topsoil, wood, trash, organic material, or construction debris will not be suitable for reuse as structural fill and should be properly disposed offsite or placed in nonstructural areas. Soils containing more than approximately 5 percent fines are considered moisture sensitive. These soils are very difficult to compact to a firm and unyielding condition when over the optimum moisture content by more than approximately 2 percent. The optimum moisture content is that which allows the greatest dry density to be achieved at a given level of compactive effort. Reuse of On-Site Soil We generally do not recommend the re-use of near-surface Uncontrolled Fill as structural fill due to the presence of brick, discarded concrete, and similar indications of construction debris Page 4of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 within this soil. Thesesoils also contained elevated fines and moisture contents significantly above theassumedoptimum moisture content for this soil. Native Advance Outwash consists of predominantly sand and gravel and this material is suitable for re-use as structural fill if allowed for in the project plans and specifications. Imported Structural Fill We recommend that imported structural fill consist of clean, well-graded sandy gravel, gravelly sand, or other approved naturally occurring granular material (pit run) with at least 30 percent retained on the No. 4 sieve, or a well-graded crushed rock. Structural fill for dry weather construction may contain on the order of 10 percent fines (that portion passing the U.S. No. 200 sieve) based on the portion passing the U.S. No. 4 sieve. Accordingly, we recommend that imported structural fill with less than 5 percent fines be used during wet weather conditions. Due to wet weather or wet site conditions, soil moisture contents could be high enough that it may be very difficult to compact even “clean” imported select granular fill to a firm and unyielding condition. Soils with over-optimum moisture contents should be scarified and dried back to more suitable moisture contents during periods of dry weather or removed and replaced withdrier structural fill. Compactionof Structural Fill Structural fill should be placed in horizontal lifts 8 to 10 inches in loose thickness and thoroughly compacted. All structural fill placed under load bearing areas should be compacted to at least 95 percent of the maximum dry density, as determined using test method ASTM D1557. The top of the compacted structural fill should extend outside all foundations and other structural improvements a minimum distance equal to the thickness of the fill. We recommend that compaction be tested after placement of each lift in the fill pad. Wet Weather Earthwork It is our experience thatnear-surface portions of Advance Outwashsoilcan be susceptible to degradation during wet weather. As a result, it may be difficult to control the moisture content of the site soils during the wet season. If construction is accomplished during wet weather, we recommend that structural fill consist of imported, clean, well-graded sand or sand and gravel as described above. If fill is to be placed or earthwork is to be performed in wet weather or under wet conditions, the contractor may reduce soil disturbance by: Limiting the size of areas that are stripped of topsoil and left exposed Accomplishing earthwork in small sections Limiting construction traffic over unprotected soil Sloping excavated surfaces to promote runoff Limiting the size and type of construction equipment used Providing gravel "working mats” over areas of prepared subgrade Removing wet surficial soil prior to commencing fill placement each day Sealing the exposed ground surface by rolling with a smooth drum compactor or rubber- tired roller at the end of each working day Providing up-gradient perimeter ditches or low earthen berms and using temporary sumps to collect runoff and prevent water from ponding and damaging exposed subgrades Page 5of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 Temporary and Permanent Slopes Actual construction slope configurations and maintenance of safe working conditions, including temporary excavation stability, should be theresponsibility of the contractor, who is able to monitor the construction activities and has direct control over the means and methods of construction. All applicable local, state, and federal safety codes should be followed. All open cuts should be monitored during and after excavation for any evidence of instability. If instability is detected, the contractor should flatten the side slopes or install temporary shoring. Temporary excavations in excess of 4 ft should be shored or sloped in accordance with Safety Standards for Construction Work Part N, WAC 296-155-657. Temporary unsupported excavations in the existing fill and Advance Outwashencountered at the project site are classified as a Type Csoil according to WAC 296-155-657 and may be sloped as steep as 1H:1V (Horizontal: Vertical). All soils encountered are classified as Type C soil in the presence of groundwater seepage. Flatter slopes or temporary shoring may be required in areas wheregroundwater flow is present and unstable conditions develop. Temporary slopes and excavations should be protected as soon as possible using appropriate methods to prevent erosion from occurring during periods of wet weather. We recommend that permanent cut or fill slopes be designed for inclinations of 2H:1V or flatter. Permanent cut or fill slopes that are part of detention ponds, retention ponds, infiltration facilities, or other earth structures intended to receive stormwater should be designed for inclinations of 3H:1V or flatter. All permanent cut slopes should be vegetated or otherwise protected to limit the potential for erosion as soon as practical after construction. Permanent slopes requiring immediate protection from the effects of erosion should be covered with either mulch or erosion control netting/blankets. Areas requiring permanent stabilization should be seeded with an approved grass seed mixture, or hydroseeded with an approved seed-mulch- fertilizer mixture. Seismic Design Considerations The Pacific Northwest is seismically active and the site could be subject to ground shaking from a moderate to major earthquake.Consequently, moderate levels of earthquake shaking should be anticipated during the design life of the project, and the proposed structure should be designed to resist earthquake loading using appropriate design methodology. For structures designed using the seismic design provisions of the 2012 International Building Code, the Advance Outwashinterpreted to underlie the sitewithin the upper 100 feet classifies as Site Class D, according to 2010 ASCE -7 Standard –Table 20.3-1, Site Class Definitions. The corresponding values for calculating a design response spectrum for the assumed soil profile type is considered appropriate for the site. Please reference the following values for seismic structural design purposes: Conterminous 48 States –2012 International Building Code Zip Code 98020 Central Latitude = 47.792240Central Longitude = -122.360144 Page 6of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 Short Period (0.2 sec)Spectral Acceleration Maximum Considered Earthquake (MCE) Value of S= 1.263(g) s Site Response Coefficient, F= 1.000(Site Class D) a Adjusted spectral response acceleration for Site Class D,S= Sx F= 1.263(g) MSsa Design spectral response acceleration for Site Class D,S = 2/3 x SM= 0.842(g) DSs One Second Period (1 sec) Spectral Acceleration Maximum Considered Earthquake (MCE) Value of S= 0.494(g) 1 Site Response Coefficient, F= 1.506(Site Class D) v Adjusted spectral response acceleration for Site Class D,S= Sx F= 0.744(g) M11v Design spectral response acceleration for Site Class D,S= 2/3 x SM= 0.496(g) D11 Foundation Support New foundations should not be placed on existing Uncontrolled Fill soils. Foundation support for the proposed improvements may be provided by continuous or isolated spread footings founded on proof-rolled, undisturbed, dense to very densenative soils or on properly compacted structural fill placed directly over undisturbed,firm and unyieldingnative soil. We recommend that qualified geotechnical personnel confirmthat suitable bearing conditions have been reached prior to placement of structural fill or foundation formwork. To provide proper foundation support, we recommend that existing topsoil, existing Uncontrolled Fill, and/or looseupper portions of the native soil be removed from beneath the building foundation area(s) or replaced with properly compacted structural fill as described elsewhere in this report. Alternatively, localized overexcavation could be backfilled to the design footing elevation with lean concrete or foundations may be extended to bear on undisturbed native soil. In areas requiring overexcavation to competent native soil, the limits of the overexcavation should extend laterally beyond the edge of each side of the footing a distance equal to the depth of the excavation below the base of the footing. If lean concrete is used to backfill the overexcavation, the limits of the overexcavation need only extend a nominal distance beyond the width of the footing. Inaddition, we recommend thatfoundation elements for the proposed structure(s) bear entirely on similar soil conditions to help prevent differential settlement from occurring. Continuous and isolated spread footings should be founded a minimum of 18 inches below the lowest adjacent final grade for freeze/thaw protection. Perimeter footings should be at least 14 inches wide and sized in accordance with the structural engineer’s prescribed design criteria and seismic considerations. Allowable Bearing Capacity Assuming the above foundation support criteria are satisfied, continuous or isolated spread footings founded directly on dense to very densenative soils or on compacted structural fill placed directly over undisturbed native soils may be proportioned using a net allowable soil bearing pressure of 2,500pounds per square foot (psf). The term "net allowable bearing pressure" refers to the pressure that can be imposed on the soil at foundation level resulting from the total of all dead plus live loads, exclusive of the weight of the footing or any backfill placed above the footing.The net allowable bearing pressure may be increased by one-third for transient wind or seismic loads. Page 7of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 Foundation Settlement Settlement of shallow foundations depends on foundation size and bearing pressure, as well as the strength and compressibility characteristics of the underlying soil. Assuming construction is accomplished as previously recommended and for the maximum allowable soil bearing pressure recommended above, we estimate the total settlement of building foundations should be less than about one inch and differential settlement between two adjacent load-bearing components supported on competent soil should be less than about one half the total settlement. Floor Support Conventional slab-on-grade floor construction is considered feasible for the planned site improvements. Floor slabs may be supported on properly prepared, firm and unyieldingnative subgrade or on structural fill placed over properly prepared native soil. New floor slabs should not be founded on existing topsoil, Uncontrolled Fill, or loose native soils. Prior to placement of the structural fill, the subgrade soil should be proof-rolled as recommended in the Site section of this report. Preparation and Earthwork For design purposes, a vertical modulus of subgrade reaction of 150 pounds per cubic inch (pci) should be expectedfor slab-on-grade floors constructed over properly prepared dense to very dense Advance Outwashor structural fill placed over native Advance Outwash. We recommend that interior concrete slab-on-grade floors be underlain by a minimum of 6 inches of compacted, clean, crushed free-draining gravel with less than 3 percent passing the U.S. Standard No. 200 sieve (based on a wet sieve analysis of that portion passing the U.S. Standard No. 4 sieve). The purpose of this layer is to provide uniform support for the slab, provide a capillary break, and act as a drainage layer. GTS recommends that material conforming to Washington State Department of Transportation Standard Specification 9- 03.12(4), “Gravel Backfill for Drains”, with the added requirement thatthe material consist of a crushed, angular aggregate material be used as capillary break material. To help reduce the potential for water vapor migration through floor slabs, at a minimum a continuous impermeable membrane of 10-to 15-mil polyethylene sheeting with tape-sealed joints should be installed below the slab. The American Concrete Institute (ACI) guidelines suggest that the slab may either be poured directly on the vapor retarding membrane or on a granular curing layer placed over the vapor retarding membrane depending on conditions anticipated during construction. We recommend that the architect or structural engineer specify if a curing layer should be used. If moisture control within the building is critical, we recommend an inspection of the vapor retarding membrane to verify that all openings have been properly sealed. Exterior concrete slabs-on-grade, such as sidewalks, may be supported directly on undisturbed native or onproperly placed and compacted structural fill; however, long-termperformance will be enhanced if exterior slabs are placed on a layer of clean, durable, well-draining granular material. Page 8of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 Foundation and Site Drainage Positive surface gradients should be provided adjacent to the proposed building to direct surface water away from the proposed building and toward suitable drainage facilities. Roof drainage should not be introduced into the perimeter footing drains, but should be separately discharged directly to the stormwater collection system or asimilar municipality-approvedoutlet. Pavement and sidewalk areas, if present,should be sloped and drainage gradients should be maintained to carrysurface water away from the building towards an approved stormwater collection system. Surface water should not be allowed to pond and soak into the ground surface near buildings or paved areas during or after construction. Construction excavations should be sloped to drain to sumps where water from seepage, rainfall, and runoff can be collected and pumped to a suitable discharge facility. To reduce the potential for groundwater and surface water to seep into interior spaces,we recommend that an exterior footing drain system be constructed around the perimeter of new building foundations as shown in the Typical Footing DrainSection, Figure 3. The drain should consist of a minimum 4-inch diameter perforated pipe, surrounded by a minimum 12 inches of filtering media with the discharge sloped to carry water to an approved collection system. The filtering media may consist of open-graded drain rock wrapped by a nonwoven geotextile fabric (such as Mirafi 140N, or equivalent) or a graded sand and gravel filter. For foundations supporting retaining walls,drainage backfill should be carried up the back of the walland be at least12-inches wide. The drainage backfill should extend from the foundation drain to within approximately 1foot of the finished grade and consist of open-graded drain rock containingless than 3 percent by weight passing the U.S. Standard No. 200 sieve (based on a wet sieve analysis of that portion passing the U.S. Standard No. 4 sieve). The invert of the footing drain pipe should be placed at approximately the same elevation as the bottom of the footing or 12 inches below the adjacent floor slab grade, whichever is deeper, so that water will not seep through walls or floor slabs. Thedrain system should include cleanouts to allow for periodic maintenance and inspection. Resistance to Lateral Loads The lateral earth pressures that develop against retainingwalls will depend on the method of backfill placement, degree of compaction, slope of backfill, type of backfill material, provisions for drainage, magnitude and location of any adjacent surcharge loads, and the degree to which the wall can yield laterally during or after placement of backfill.If the wall is allowed to rotate or yield so the top of the wall moves an amount equal to or greater than about 0.001 to 0.002 times its height (a yielding wall), the soil pressure exerted will be the active soil pressure.When a wall is restrained against lateral movement or tilting (a nonyielding wall), the soil pressure exerted is the at-rest soil pressure.Wall restraint may develop if a rigid structural network is constructed prior to backfilling or if the wall is inherently stiff. We recommend that yielding walls under drained conditions be designed for an equivalent fluid density of 35 pounds per cubic ft (pcf) for structural fill or dense to very dense native Advance Outwashin active soil conditions.Nonyielding walls under drained conditions should be designed for an equivalent fluid density of 55 pcf for structural fill in at-rest conditions.Design of walls should include appropriate lateral pressures caused by surcharge loads located within a horizontal distance equal to or less than the height of the wall.For uniform surcharge pressures, a uniformly distributed lateral pressure equal to 35 percent and 50 percent of the vertical surcharge pressure should be added to the lateral soil pressures for yielding and nonyielding walls, respectively. GTS also recommends that a seismic surcharge pressure of Page 9of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 12H be included where H is the wall height in feet. The seismic surcharge should be modeled as a rectangular distribution with the resultant applied at the midpoint of the wall. Passive earth pressures developed against the sides of building foundations, in conjunction with friction developed between the base of the footings and the supporting subgrade, will resist lateral loads transmitted from the structure to its foundation.For design purposes, the passive resistance of well-compacted fill placed against the sides of foundations may be considered equivalent to a fluid with a density of 250 pounds per cubic ft.The recommended value includes a safety factor of about 1.5 and isbased on the assumption that the ground surface adjacent to the structure is level in the direction of movement for a distance equal to or greater than twice the embedment depth.The recommended value also assumes drained conditions that will prevent thebuildup of hydrostatic pressure in the compacted fill.Retaining walls should include a drain system constructed in general accordance with the recommendations presented in the section of this report. In design computations, the upper Foundation and Site Drainage 12 inches of passive resistance should be neglected if the soil is not covered by floor slabs or pavement.If future plans call for the removal of the soil providing resistance, the passive resistance should not be considered. An allowable coefficient of base friction of 0.35 for undisturbed native soil or structural fill, applied to vertical dead loads only, may be used between the underlying soil and the base of the footing. However, if passive and frictional resistance are considered together, one half the recommended passive soil resistance value should be used since larger strains are required to mobilize the passive soil resistance as compared to frictional resistance. A safety factor of about 1.5 is included in the base friction design value. We do not recommend increasing the coefficient of friction to resist seismic or wind loads. Utilities It is important that utility trenches be properly backfilled and compacted to reducecracking or localized loss of foundationor slabsupport. It is anticipated that excavations for new shallow underground utilities will be indense to very dense Advance Outwashwith varying amounts of gravel and scattered cobblesor Uncontrolled Fill with scattered construction debris. Trench backfill in improved areas (beneath structures, sidewalks, etc.) should consist of structural fill as defined earlier in this report. Outside of improved areas, trench backfill may consist of re-used native fillprovided it can be compacted to the project specifications. Trench backfill should be placed and compacted in general accordance with the recommendations presented in the section of this report. Fill and Compaction Surcharge loads on trench support systems due to construction equipment, stockpiled material, and vehicle traffic should be included in the design of any anticipated shoring system. The contractor should implement measures to prevent surface water runoff from entering trenches and excavations. In addition, vibration as a result of construction activities and traffic may cause caving of the trench walls. Actual trench configurations arethe responsibility of the contractor. All applicable local, state, and federal safety codes should be followed. All open cuts should be monitored by the contractor during excavation for any evidence of instability. If instability is detected, the contractor should flatten the side slopes or install temporary shoring. If groundwater or groundwater seepage is present, and the trench is not properly dewatered, the soil within the Page 10of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 trench zone may be prone to caving, channeling, and running. Trench widths may be substantially wider than under dewatered conditions. Stormwater Infiltration Potential From the subsurface information obtained from our exploration pits, 8representative soil samples were selected and mechanically tested for grain size distribution and interpretation according to the United States Department of Agriculture (USDA) soil textural classification. These classifications are reproduced in Table 1 below. TABLE 1 Soil Sample USDA Classification Test Pit NumberSample Depth (feet)USDA Classification TP-11.5Loamy Sand TP-13Loamy Sand TP-17.5Sand TP-33.0Sand TP-35.0Sand TP-42.0Loamy Sand Sand TP-43.0Loamy Sand Sand TP-52.8Sand Our approach for determining infiltration feasibility is based on elements of Exhibit A from the Stormwater Code Supplement to Edmonds Community Development Code Chapter 18.30, running a USDA soil textural classification based on criteria established in the 2005 Stormwater Management Manual for Western Washington (Stormwater Manual), our subsurface exploration program, and our experience in the area.Based on the results of our USDA textural analysis and interpretation of our soil logs, the near surface fill soil (TP-1 @ 1.5 feet and TP-1 @ 3 feet) and the weathered portions of the Advance Outwash (TP-4 @ 2.0 feet, and TP-4 @ 3.0 feet) classify as Loamy Sand and the native Advance Outwashsoils (TP-1 @ 7.5 feet, TP-3 @ 3 feet, TP-3 @ 5 feet, and TP-5 @ 2.8 feet) classify as Sand. The Stormwater Manual does not recommend the infiltration of stormwater into Uncontrolled Fill soils. Uncontrolled Fill should be completely removed from areas where infiltration is desired and infiltration facilities should be founded in either native Advance Outwash or imported structural fill that has defined properties and a known infiltration rate. GTS can assist the design team with developing infiltration rates for structural fill as part of a separate scope of services. The Stormwater Manual recommends an infiltration rate of 2 inches per hour for USDA Sand. It is, however, our experience that the USDA approach may somewhat overestimate the long-term infiltration design rates of glacially consolidated dense to very dense soil.However, the analysis above suggests that the conventional infiltration of stormwater is feasible on the site, and no Page 11of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 restrictive layers or groundwater that would otherwise impede infiltration was encountered within the limits of our explorations. Due to the potential for “real world” infiltration rates being different than those provided for the Stormwater Manual, we recommend that long-term design infiltration rates for any proposed infiltration facilities be determined by in-situ methods such as PIT (Pilot Infiltrating Test) testing. At the time of this report, Civil design has not been completed and the locations, sizes, and depths of infiltration facilities have not been established. GTS recommends that these parameters be established prior to further investigation to allow fortesting at the location and depth of the proposed facilities. Stormwater Treatment Capacity Cation Exchange Capacity (CEC), organic content and pH tests were performed by Northwest Agricultural Consultants on twosamples collected during this investigation. These samples were considered representative of the near-surface, weathered Advance Outwash and the unweathered Advance Outwash encountered at depth. A copy of the laboratory test results is attached at the end of this report. A summary of the test results is presented in Table 2on the following page. Table 2 Testing of Treatment Capacity Parameters Sample Organic Test Pit pH CEC Depth Geologic UnitContent Number(unitless)(meq/100g) (Feet)(percent) Weathered TP-42.06.46.81.98 Advance Outwash TP-43Advance Outwash6.24.61.55 The Department of Ecology Stormwater Management Manual for Western Washington (Ecology), SSC-6states that the Cation Soil Physical and Chemical Suitability for Treatment Exchange Capacity (CEC) of the treatment soil must be greater than or equal to 5 milliequivalents CEC/100g dry soil. SSC-6 also recommends a minimum organic content of 1 percent of the dry weight. Testing indicates that the Weathered Advance Outwash, typically encountered within the upper few feet of soil across the site, may be suitable for stormwater treatment purposes,as indicated by Cation Exchange Capacities of 5.0 or greater. The AdvanceOutwash encountered at greater depths, however, is not suitable for stormwater treatment purposes due to Cation Exchange Capacitiesobserved to be significantly below 5.0. The Advance Outwash could also be amended to have properties recommended in the Stormwater Manual for an amended soil. Amendment could include mixing higher fines and organic content soils or adding mulch (or other admixtures) to elevate the cation exchange capacity. It has been our experience, however, that it is challenging to obtain a uniformly blended amended soil using conventional construction equipment to mix on-site soils and imported materials. On-site amended soil would require additional testing of the amended soil to confirm compliance with Ecology-recommended soil properties. Additionally, amendment of the Advance Outwash has the potential to reduce the infiltration potential the soil. GTS is available Page 12of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 to perform additional laboratory testing and provide revised recommendations as part of an expanded scope of services if the soil is to be amended. Alternatively, the Owner mayelect to import amended soils with the desired properties for planned treatment facilities. Recommendations for Temporary Erosion and Sediment Control We recommend the site specific Stormwater Pollution Prevention Plan (SWPPP) and/or Temporary Erosion and Sediment Control Plan (TESC) focus on the implementation of source control BMP’s specifically targeting SWPPP Element #5, Stabilize Soils (Volume 2, Chapter 4.1 of the Stormwater Management Manuel for Western Washington). These BMP’s are intended to limit the potential for site soils to become suspended within stormwater. Once suspended, silt and clay may prove time consuming and/or costly to remove from stormwater prior to discharge. If large areas of the site soil are left exposed during wet conditions, the turbidity of stormwater may be difficult to control. We anticipate treatment BMP’s to manage highly turbid stormwater may be costly and/or require large portions of the site to implement. We recommend all temporary erosion and sediment control measures conform to the Washington State Department of Ecology Best Management Practices (BMP’s) and/or other applicable regulatory bodies. Geotechnical Consultation and Construction Monitoring GeoTest Services recommends that we be involved in the project design review process. The purpose of the review is to verify that the recommendations presented in this report have been properly interpreted and incorporated in the plansand specificationsfor this project. We recommend that geotechnical construction monitoring services be provided. These services should include observation by GeoTest personnel duringsubgrade preparation operations, structural fill placement,andto confirmthat design subgrade conditions are obtained beneath the proposed improvements. We also recommend that periodic field density testing be performed to verify that the appropriate degree of compaction is obtained. The purpose of these services would be to observe compliance with the design concepts, specifications, and recommendations of this report. In the event that subsurface conditions differ from those anticipated before the start of construction, GeoTest Services would be pleased to provide revised recommendations appropriate to the conditions revealed during construction. GeoTest is also available to provide a full range of materials testing and special inspection during building construction as required by the local building department and the International Building Code. This may include specific construction inspections on materials such as reinforced concrete, reinforced masonry, wood framing and structural steel. These services are supported by our fully accredited materials testing laboratory. Page 13of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 USE OF THIS REPORT GeoTest Services has prepared this report for the exclusive use of the Westgate Woods, LLC and their design consultants for specific application to the design of the Edmonds Townhouses project,located at 9511 Edmonds Way in Edmonds, Washington. Use of this report by others is at the user’s sole risk. This report is not applicable to other sites. Our services have been conducted in accordance with generally accepted practices of the geotechnical engineering profession; no other warranty, express or implied, is made as to the professional advice included in this report. Our site explorations indicate subsurface conditions at the dates and locations indicated. It is not warranted that they are representative of subsurface conditions at other locations andtimes. The analyses, conclusions, and recommendations contained in this report are based on site conditions to the limited depth of our explorations at the time of our exploration program, a geological reconnaissance of the area, and a review ofpreviously published USGS geological information for the site. If variations in subsurface conditions are encountered during construction that differs from those in this report, we should be allowed to review the recommendations contained in this reportand, if necessary, make revisions. If there is a substantial lapse of time between submission of this report and the start of construction, or if conditions change due to construction operations at or adjacent to the project site, we recommend that we review this report to determine the applicability of the conclusions and recommendations contained herein. The earthwork contractor is responsible to perform all work in conformance with all applicable WISHA/OSHA regulations. GeoTest Services, Inc. should not be assumed to be responsible for job site safety on this project, and this responsibility is specifically disclaimed. Page 14of 15 GeoTest Services, Inc. REVISION 1June 10, 2016 Edmonds Townhouses, Edmonds, WAJob No. 16-0234 We appreciate the opportunity to provide geotechnical services on this project and look forward to assisting you during the construction phase. If you have any questions regarding the information contained in this report, or if we may be of further service, please contact the undersigned. Respectfully Submitted, GeoTest Services, Inc. Justin Brooks, L.E.G.Edwardo Garcia, P.E. Engineering GeologistProject Geotechnical Engineer Attachments:Figure 1 Vicinity Map Figure 2 Site and Exploration Plan Figure 3Typical Footing and Wall Drain Section Figure 4Soil Classification System and Key Figures 5-7Boring Logs Figure 8and 9Grain Size Analysis AttachedNorthwest Agricultural Consultants Results (1 page) REFERENCES Minard, J.P., 1985.Geologic Map of the Everett 7.5 Minute Quadrangle, Snohomish County, Washington. US Geological Survey, Miscellaneous Field Studies Map MF-1748. Washington State Department of Ecology Water Quality Program. February 2005. Stormwater Management Manual for Western Washington.Publication Numbers 05-10-029 through 05-10-033. Page 15of 15 ProjectSite NORTH MapfromACMEMapper2.1 Project Scale:none By:JB Date: 5-13-16 GEOTESTSERVICES,INC. 16-0234 VICINITYMAP 741MarineDrive ET DMONDSOWNHOUSE Bellingham,WA98225 Figure 9511EW phone:(360)733-7318 DMONDSAY 1 fax:(360)733-7418 E,W DMONDSASHINGTON TP-1 TP-5 TP-2 TP-3 TP-4 N ORTH TP-# =TestPitExplorationLocation Project Scale:AsShown By:JB Date: 5-13-16 GEOTESTSERVICES,INC. 16-0234 SITEANDEXPLORATIONPLAN 741MarineDrive ET Bellingham,WA98225 Figure DMONDSOWNHOUSE 9511EW phone:(360)733-7318 2 DMONDSAY fax:(360)733-7418 E,W DMONDSASHINGTON SHALLOWFOOTINGSWITHINTERIORSLAB-ON-GRADE TypicalFraming CompactedImperviousSoil (12inchminimum) FloorSlab orPavement (2inchminimum) VaporBarrier Slopetodrainaway fromstructure. CoarseGravelCapillaryBreak (6inchminimumtypicallyclearcrushed) SuitableSoil FreeDrainingSand andGravelFill ApprovedNon-woven GeotextileFilterFabric (18inchminimumfabriclap) SuitableSoil DrainageMaterial (DrainRockorClear AppropriateWaterproofing CrushedRockw/nofines) AppliedtoExteriorofWall FourInchDiameter,Perforated,RigidPVCPipe (Perforationsorienteddown,wrappedinnon-woven geotextilefilterfabric,directedtosuitabledischarge) Notes: FootingsShouldbeproperlyburiedforfrostprotectioninaccordancewith InternationalBuildingCodeorlocalbuildingcodes (Typically18inchesbelowexteriorfinishedgrades) Project Scale:None By:JB Date: 5-13-16 GGEEOOTTEESSTTSSEERRVVIICCEESS,,IINNCC.. 16-0234 TYPICALFOOTING&WALLDRAINSECTION 741MarineDrive ET Bellingham,WA98225 DMONDSOWNHOUSE Figure 9511EW 3 phone:(360)733-7318 DMONDSAY fax:(360)733-7418 E,W DMONDSASHINGTON 4 5 6 7 8 9 X____________________________________________ Yield Goal SampleI D per 100 grams) Bases(meq. Total Fertilizer Bray 1P ppm lbs. per. Chloride acre Client No.: 9678 Date Received: 05-10-2016 % Base Sat. Crop per 100 grams) (meq. 6.84.6 CEC Copper Report No.: 38362 Page: 1 of 1 ppm GEOTEST SERVICES INC BELLINGHAM, WA 98225 Iron ppm Crop Year Manga- nese ppm Last Year's Crop 741 MARINE DR Sample ID pH Loss on Ignition OM Cation Exchange Capacity 3aae3b-67130 Zinc ppm TP4-2 6.4 1.98% 6.8 meq/100gTP4-3 6.2 1.55% 4.6 meq/100g Boron ppm SOIL Eff. Field Name per 100 grams) Sodium (meq. Magne- per 100 grams) (meq. sium per 100 Calciumgrams) (meq. Estimated Total Nitrogen Available to Crop 38833 K(ace) ppm Job No. 16-0234 Field No. P(ace) ppm Northwest Agricultural Consultants K(bic) (509) 783-7450 Fax: (509) 783-5305 ppm P(bic) ppm Percent Organic 1.981.55 Matter Kennewick, WA 99336 (mmhos Soluble Sampler Salts /cm) 2545 West Falls Estimated Nitrogen Release from Organic Matter 6.46.2 pH Sulfur ppm CEC Method: EPA 9081 lbs/acre NH4-N lbs/acre NO3-N Grower Available 0.00 Inches Comments Total Depth (ft.) 12 1 REPORT LIMITATIONS AND GUIDELINES FOR ITS USE Subsurface issues may cause construction delays, cost overruns, claims, and disputes. While you cannot eliminate all such risks, you can manage them. The following information is provided to help: Geotechnical Services are Performed for Specific Purposes, Persons, and Projects At GeoTest our geotechnical engineers and geologists structure their services to meet specific needs of our clients. A geotechnical engineering study conducted for a civil engineer may not fulfill the needs of an owner, a construction contractor or even another civil engineer. Because each geotechnical engineering study is unique, each geotechnical engineering report is unique, prepared solely for the client. No one except you should rely on your geotechnical engineer who prepared it. And no one – not even you – should apply the report for any purpose or project except the one originally contemplated. Read the Full Report Serious problems have occurred because those relying on a geotechnical engineering report did not read it all. Do not rely on an executive summary. Do not read selected elements only. A Geotechnical Engineering Report is Based on a Unique Set of Project-Specific Factors GeoTest’s geotechnical engineers consider a number of unique, project-specific factors when establishing the scope of a study. Typical factors include: the clients goals, objectives, and risk management preferences; the general nature of the structure involved its size, and configuration; the location of the structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utilities. Unless GeoTest, who conducted the study specifically states otherwise, do not rely on a geotechnical engineering report that was: not prepared for you, not prepared for your project, not prepared for the specific site explored, or completed before important project changes were made. Typical changes that can erode the reliability of an existing geotechnical engineering report include those that affect: the function of the proposed structure, as when it’s changed, for example, from a parking garage to an office building, or from a light industrial plant to a refrigerated warehouse, elevation, configuration, location, orientation, or weight of the proposed construction, alterations in drainage designs; or composition of the design team; the passage of time; man-made alterations and construction whether on or adjacent to the site; or by natural alterations and events, such as floods, earthquakes or groundwater fluctuations; or project ownership. Always inform GeoTest’s geotechnical engineer of project changes – even minor ones – and request an assessment of their impact. Geotechnical engineers cannot accept responsibility or liability for problems that occur because their reports do not consider developments of which they were not informed. 1 Information in this document is based upon material developed by ASFE, Professional Firms Practicing in the Geosciences( asfe.org) Subsurface Conditions Can Change This geotechnical or geologic report is based on conditions that existed at the time the study was performed. Do not rely on the findings and conclusions of this report, whose adequacy may have been affected by: the passage of time; by man-made events, such as construction on or adjacent to the site; or by natural events, such as floods, earthquakes, or groundwater fluctuations. Always contact GeoTest before applying the report to determine if it is still relevant. A minor amount of additional testing or analysis will help determine if the report remains applicable. Most Geotechnical and Geologic Findings are Professional Opinions Our site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. GeoTest’s engineers and geologists review field and laboratory data and then apply their professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ – sometimes significantly – from those indicated in your report. Retaining GeoTest who developed this report to provide construction observation is the most effective method of managing the risks associated with anticipated or unanticipated conditions. A Report’s Recommendations are Final Not Do not over-rely on the construction recommendations included in this report. Those recommendations are not final, because geotechnical engineers or geologists develop them principally from judgment and opinion. GeoTest’s geotechnical engineers or geologists can finalize their recommendations only by observing actual subsurface conditions revealed during construction. GeoTest cannot assume responsibility or liability for the report’s recommendations if our firm does not perform the construction observation. A Geotechnical Engineering or Geologic Report may be Subject to Misinterpretation Misinterpretation of this report by other design team members can result in costly problems. Lower that risk by having GeoTest confer with appropriate members of the design team after submitting the report. Also, we suggest retaining GeoTest to review pertinent elements of the design teams plans and specifications. Contractors can also misinterpret a geotechnical engineering report. Reduce that risk by having GeoTest participate in pre-bid and preconstruction conferences, and by providing construction observation. Do not Redraw the Exploration Logs Our geotechnical engineers and geologists prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors of omissions, the logs included in this report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable; but recognizes that separating logs from the report can elevate risk. Give Contractors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can make contractors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give contractors the complete geotechnical engineering report, but preface it with a clearly written letter of transmittal. In that letter, consider advising the contractors that the report was not prepared for purposes of bid development and that the report’s accuracy is limited; encourage them to confer with the GeoTest and/or to conduct 1 Information in this document is based upon material developed by ASFE, Professional Firms Practicing in the Geosciences( asfe.org) additional study to obtain the specific types of information they need or prefer. A pre-bid conference can also be valuable. Be sure contractors have sufficient time to perform additional study. Only then might you be in a position to give contractors the best information available, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions. In addition, it is recommended that a contingency for unanticipated conditions be included in your project budget and schedule. Read Responsibility Provisions Closely Some clients, design professionals, and contractors do not recognize that geotechnical engineering or geology is far less exact than other engineering disciplines. This lack of understanding can create unrealistic expectations that can lead to disappointments, claims, and disputes. To help reduce risk, GeoTest includes an explanatory limitations section in our reports. Read these provisions closely. Ask questions and we encourage our clients or their representative to contact our office if you are unclear as to how these provisions apply to your project. Environmental Concerns Are Not Covered in this Geotechnical or Geologic Report The equipment, techniques, and personnel used to perform an environmental study differ significantly from those used to perform a geotechnical or geologic study. For that reason, a geotechnical engineering or geologic report does not usually relate any environmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated containments, etc. If you have not yet obtained your own environmental information, ask your geotechnical consultant for risk management guidance. Do not rely on environmental report prepared for some one else. Obtain Professional Assistance to Deal with Biological Pollutants Diverse strategies can be applied during building design, construction, operation, and maintenance to prevent significant amounts biological pollutants from growing on indoor surfaces. Biological pollutants includes but is not limited to molds, fungi, spores, bacteria and viruses. To be effective, all such strategies should be devised for the express purpose of prevention, integrated into a comprehensive plan, and executed with diligent oversight by a professional biological pollutant prevention consultant. Because just a small amount of water or moisture can lead to the development of severe biological infestations, a number of prevention strategies focus on keeping building surfaces dry. While groundwater, water infiltration, and similar issues may have been addressed as part of this study, the geotechnical engineer or geologist in charge of this project is not a biological pollutant prevention consultant; none of the services preformed in connection with this geotechnical engineering or geological study were designed or conducted for the purpose of preventing biological infestations. 1 Information in this document is based upon material developed by ASFE, Professional Firms Practicing in the Geosciences( asfe.org)