Notes
Letter dated May 23, 2000 from Azous Environmental Sciences to Ms. Gail Terzi and Mr. Jonathan Freedman, US Army Corps of Engineers Regulatory Section, Seattle District, submitted on behalf of the Airport Communities Coalition (ACC). Reviews wetland impacts to Wetland 43 resulting from construction of the temporary SR-509 interchange associated with the third runway at Seattle-Tacoma International Airport, located in Burien north of S. 176th Street. Author, a professional wetland scientist (SWS certification 001067), concludes construction will cause direct sedimentary discharge impacts to Wetland 43 from stormwater events. Addresses inconsistent wetland boundary delineations across HNTB Corporation plans (February 24, 2000), HNTB hydraulic report (April 12, 2000), and Parametrix Inc. reports (August 1999 Wetland Delineation Report, Wetland Functional Assessment and Impact Analysis, Wetlands Re-Evaluation Document, and May 3, 2000 memorandum). Identifies inadequate erosion controls (wattles, silt fence), steep 50-percent slopes, proximity of construction zone to Wetland 43 (as little as 40 feet), stormwater facility sited within wetland boundaries, and Walker Creek and Miller Creek downstream impacts. Cites buffer distance research requiring 33–197 feet of separation for sediment protection. Exhibit AR022964.