EXH0170018385

Since I wasn'tat the meetingandsinceI ambeing transitionedaway fromSeaTac review,I amprovidingthis memointernallyforyou to decidehowtheyshouldbereflectedinthe finalnotes. p. 5 Update - NPDESmajormodification:if the509 interchangeis part of the proposalbeingreviewedfor404 and401 (which it is,perthe Corps),then the 401 mustaddressanydirect/indirectimpacts. We may or may notneedthe finalmajorroodto be issuedbeforethe 401, butat thevery least,the 401 doesneedan approvedstormwaterplanat the interchangeforthe samereasonsthatwe needa finalstormwaterplan for the restof the airport- todeterminewhethertherewillbe impacts to aquaticresourcesdueto the location/size/etc,of the stormwater facilities. recommendaddinglanguageto this issuestatingthat Ecologyapproval AR 018385.= -_ of the stormwaterplanforthe509 interchangewillbe neededfor401 issuance / "7O_ / -I'zoo 11. i DOES/17/01--_ "73 p. 5 Update- SouthAccess/ Tyee Pond:anyimpactsto Tyee Ponddueto itsuse as a spillcontainmentfacilitymaybe includedas partof the ' Corps'404 review;,if so,thenthoseimpactswouldbe part of the 401 _ review. Regardlessof theCorps'position,however,I believeEcology needsto independentlyevaluatethe associatedimpacts- the Tyee Pond is partof the proposedprojectmitigationand is subjectto project-relatedimpacts(e.g., on¢oingvegetationremoval/disturbanceto maintainspillcontainmentandstormwaterfunctions,directimpactsof spillsonthe wetlandfunctions,etc.), so anymaintenancerequirements, easementlanguageallowingcertainactivities,etc.wouldhaveto be includedas a 401 condition. p. 5 Update - Des MoinasCreekFlowAugmentation:the suggested conditionlanguagein these notesdoesnotreflectthediscussionat lastweek'sintemalmeeting.The languageinthesenotesis the languageI was concernedabout,inthatitcouldallowseveralyearsof impactsto Des MoinesCreekflowswithoutmitigationinplace. The low flow impactis causednotonlybyaddingimpervioussurfaces,butalso byaddingfill and thendetainingandreroutingstormw terduringthe constructionperiodwellbeforepavementis addedat the topof the fill. We hadagreed lastweekthat, at the veryleast,the proposedlanguage be changedto not allowanyfillto be placedfor the parts of the projectin the Des MoinesCreekbasinuntilflowaugmentationwas A provided(i.e., certaintyaboutthesourceof waterandEcologyapproval _f _ of a treatmentsystem). Eventhougha conditionwith that language wouldstillbe provisional,itwouldprovidea degreeof reasonable assurancethat is notprovidedbythe currentdraftlanguagein these meetingnotes. p. 6 Issue - Temporaryconstructionin SASh,footprint:It makesno sense to allowthis facilitybeforea 401 or 404 isissued,giventhe issues identifiedin the Flow Augmentationsectionabove,and giventhatthe work is part of the proposedSeaTacexpansionbeingreviewedfor 4011404 (andESA). Placingfill, addingimpervioussurfaces,and…

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PSCAA Advisory Council Meeting Agenda
Add to CalendarMWednesday Mar 11, 9:00am - 11:35am
1904 3rd Avenue, Suite 105, Seattle, WA 98101
Call to order – Roll Call – Quorum Established – Land Acknowledgement We would like to acknowledge that our Agency operates in four present-day counties, which are the traditional lands of the Coast Salish people, past and present. This acknowledgement does not take the place of authentic relationships with indigenous communities in our jurisdiction and [...]