EXH0235018954

Subject: Follow-up comments on low streamflow analyses Thank you for meeting with the Airport Community Coalition's team of technical expertson July 10, 2001 to hear a first-hand sunmutxy of outstanding SeaTac Airport 401 Certification issues, including our comments on low streamflow impacts from proposed development actions. This follow-up letter is being submitted in response to additional low streamflow analyses materials which were subsequently obtained by the ACC from Ecology on July 12, 2001. The specific matefiab are two email documents regarding"low flow data for Des Moines Creek," with spreadsheet attaclmum_ transmitted on July 6, 2001 by Parametrix (the Port's consultant) to Ecology and others. Ourfollow-up comments also apply to four entaildocuments regarding "Monday Meeting" and "IVfillerCreek Update" with low-flow analysis spreadsheet attachments for Des Moines, Walker, and lVfillerCreek, transmitted on July 12 and 13, 2001 by Parametrix to Ecology, and obtained by the ACC on July 18, 2001. The additional materials show that a low streamflow analyses is in progress which has the appearance of being significantly more detailed than the analyses which were available for review at the time of the latest public comment period. Our concern, based on the Port's responses to our February 15, 2001 comment letter, is that these seemingly-detailed analyses are likely still based on models ofuncertain suitability for assessing upper-basin low-flow impacts, that airport impacts on low streamflows are likely still being underestimated, and that the corresponding mtficiency of any proposed mitigation measures will likely continue to be highly uncertain. Our underlying concerns as…

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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 [...]