EXH0772028003

Subject: Briefing Decision - forthe Portof Seattle Sea-Tac InternationalAirport ThirdRunway Proposals- (Expanded Version for Tuesday Meeting) Followinganextensiveandthoroughregulatoryreviewanddecision-makingprocess,we havereachedarecommendationtoapprovea401WaterQualityCertificationforthePort ofSeattle's(Port)ThirdRunwayandrelatedprojectproposals.ThePorthassubmitted plansthat,togetherwithwhatwe believearenecessary401conditions,satisfy requirements pursuantto all pertinentenvironmental laws andregulations. The Port's StorrnwaterManagement and Low-Flow Management Plans (SNIP and LFMP),and NaturalResource Mitigation Plan (NRMP), togetherwith our proposed conditions regardingconstruction Best Management Practices (BMPs), additional natural resource mitigation, and requirements for clean fill, give us reasonable assurance waterqualityand otheraquaticresources will be protected. Below is a summaryof the Port'sproposals; knownand expected project impacts;permit requirements;agency environmental objectives; mitigation requixements; andmajorareas of concern surroundingthedecision-making process/adequacy of the Port's proposals. THEPORT'S PROPOSAL: Implement selected projects from the Port of Seattle(POS) Sea-Tac International Airport (STIA) list of MasterPlan improvements. Specifically:.Construct an 8,500 - foot (1.6 mile) parallel third runway west of existing runways at STIA. Construct two new Runway Safety Areas 0LSAs) on the north end of existing runways; construct the South Aviation Support Area (SASA) for increased airportsupportand maintenance facilities. LOCATION: King County, City of SeaTac. The Green-Duwamish Watershed/Basin, Des Moines Creek,MillerCreekandWalkerCreeksub-basins.CityofAuburn,isthelocationforthe Port'soff-sitewetlandmitigation. IMPACTS: Implementation of the work involves development and/orredevelopment of approximately 700 acres in uplands (outside of U.S. ArmY Corps of Engin.-ers [ACOE] AR 028003 jurisdiction). Fill in_/_tlands includes 8.17 acres of acres of scrub-shrub and 7.22 acres of_nt wetlands. The proposed work also requires filling and reconstruction of approximately 980 linear feet of Miller Creek, 1,290 linear feet of drainage channels in Miller Creek sub-basin, and 100 linear feet of drainage channel in the Des Moines Creek sub-basin, l In addition to the permanent wetland…

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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 [...]