EXH0613024316

Subject: Comments on Recently Received Documents Pertaining to Seattle Tacoma International Airport Project Third Runway- Low Flow Analysis - GeoSyntec Consultants (GeoSyntec) has been retained on behalf of the Airport Communities Coalition (ACC) to provide a technical review of investigation, analysis and design relating to geotechnical and hydrogeological elements of the proposed Third Runway Expansion Project at the Seattle Tacoma International Airport. GeoSyntec has previously commented on seismic and geotechnical aspects of the embankment fill and Mechanically Stabilized Earth Wall. In my October 2001 declaration in support of ACC's motion for stay, I raised numerous concerns relating to the Port's Low How Analysis. This letter presents an expansion on the issues raised in the declaration based largely on review of the November 27, 2001 report by Pacific Groundwater Group (PGG) titled "Port of Seattle - Sea-Tat Third Runway - Embankment Fill Modeling in Support of Low StreamflowAnalysis." Introduction The purpose of the low flow analysis is to evaluate the impact that construction of the Third Runway Embankment will have on the rate at which runoff and infiltration recharge the creeks. The impact of the embankment is that it stores infiltrating water and subsequently releases it to recharge the low stream flows at different times than if the embankment were not in place. To mitigate the impact of the embankment, excess water must be stored and released to the creeks to maintain conditions that existed prior to the construction of the embankment. The analysis must be able to predict the magnitude…

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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 [...]