Notes
Water Resources Consulting LLC (Peter Willing, Ph.D.), engaged by the Airport Communities Coalition (ACC), submits a follow-up technical response dated July 3, 2001 to the U.S. Army Corps of Engineers (USACE Regulatory Branch, Reference 1996-4-02325) and Washington State Department of Ecology regarding the Port Of Seattle’s Section 404/401 permit application for the Sea-Tac Airport Master Plan Update (STIA). The letter and attachment rebut the Port Of Seattle’s April 30, 2001 response on the Comprehensive Stormwater Management Plan, disputing claims about impervious area increases (307 acres) in Des Moines, Miller Creek, and Walker Creek basins, Industrial Wastewater System (IWS) diversions (45 acres Miller Creek, 58 acres South Aviation Support Area Des Moines Creek, 217 acres per NHC 2001), hydrologic divide changes, and the Governor’s water quality certification language. Also challenges Port’s reliance on biofiltration swales and filter strips as BMPs for metals removal, citing Claytor et al. (1996), Yousef et al. (1985), EPA/ASCE BMP effectiveness database (1999), and Washington State APWA comments on draft Ecology Stormwater Manual, noting low or negative removal rates for soluble metals including cadmium, copper, zinc, aluminum, chromium, and lead. References King County Surface Water Design Manual (1998), NPDES permit, Beyerlein (1999), and EPA (2001). AR number AR021176.