EXH0231A018931

Subject: Follow-up comments on stormwater management plan for proposed 3rd runway development actions at Seattle-Tacoma International Airport.) Northwest Hydraulic Consultants (nhc) has been retained on behalf of the Airport Communities Coalition to provide a technical review ofstormwater facilities and related streamflow impacts from the proposed 3rd runway development at SeaTac airport. By a letter dated November 24, 1999, we provided our initial comments from a technical review of documents describing the Stormwater Management Plan (SMP) for Master Plan Update Improvements at Seattle-Tacoma International Airport. Responses to public comments, including those submitted by nh¢, were made in a document dated March I0, 2000, by or on behalf of the Port of Seattle. The purpose of this letter is to provide follow-up comments based on those responses, and on a review of recently-released hydrologic model input files which were used for the SMP. The input files at issue were the basis for hydrologic aspects of environmental impact .. assessments and for analyses of mitigation measures including existing and proposed regional detention facilities. Those input files were not published with the November 1999 SMP but were made available to us on March 7, 2000, at the same time as the input files were provided to King County for review. The response document dated March 10, 2000, satisfactorily addresses very few of our concerns raised previously. Instead, our concerns have been confirmed and heightened by findings of numerous, significant discrepancies and inconsistencies in the hydrologic modeling files, and by the apparent absence of a…

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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 [...]