EXH0155018326

.:. RE: Wetland Hydrology and the Third Runway EmbankmentFill Chicago 4978-06 CC: ElizabethLeavitt, Port of Seattle Denver ._ During the courseof the ThirdRunway project, the Port of Seattleanditsconsultantshave evaluated a numberof issuesthat relate to impacts to and preservationof the wetlandsand maintainingbaseflow to the creeks resultingfrom constructionof the Third Runway Embankment Thismemorandum presentsthe USArmy Corpsof Engineers(Corps) a Fairbanks summaryand guide regarding these studiesand how the analysesaddresskey issuesof concern regarding long-term protection of wetlands hydrology. We outline the understandingof currentconditionsat theThird Runwaysite,as they relate se_eyCity tO the main hydrologicprocessesthat maintainthe wetlandsandbaseflowto Miller and Walker Creeks. We then describe the work done to assessthe potentialfor the Third Runway to affectthese hydrologicprocesses,and how constructionof the project is •:._ designedto avoid or mitigateadverse effects. •_. Juneau UNDERSTANDIN(OF EXISTINGCONDITIONS In this section, we answerthe question:What are the soil and hydrologicfeaturesand Long8each characteristicsat or near the Third Runwaysite that maintain wetlandhydrology? Hydrologicand GeologicSetting Portland The existingconditionsatThird Runway site havebeen documentedfor bothwetlandsand hydrology/hydrogeologyaspart of the Final Environmental Impact 5tatement(FEIS) for the proposedMaster Plan Update (FA_/Port of Seattle1996), of which the ThirdRunway isa part: Seattle '9;'):.J.,rl,;ewAvenue. Edsr AR 018326 ;K" ' '.,'I,. 11:.,_l (]104. • N • HNTB 4978-06 October 30, 2001 Page 2 • Hydrologic conditions in the basins are summarized as part of the Hydrologic Modeling Study(Montgomery Water Group 1995) presented in Appendix G (in Volume 3) of the FEIS. • The original Wetland Delineation and Wetland Function and Values Assessment for the project were presented in Appendix H-A and H-B (Volume 3) of the FEIS. =:…

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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 [...]