Notes
Final Supplemental Environmental Impact Statement (SEIS) prepared jointly by the FAA Northwest Mountain Region and Port Of Seattle for proposed Master Plan Update development actions at Seattle-Tacoma International Airport (Sea-Tac Airport). Covers proposed third parallel runway (Runway 16X/34X), 8,500 feet long, separated 2,500 feet from existing Runway 16L/34R; Runway 34R extension by 600 feet; new air traffic control tower; new north unit terminal; Main Terminal improvements; parking and access expansion; South Aviation Support Area for cargo and/or maintenance facilities; and relocation/redevelopment of support facilities. Analyzes environmental consequences including wetland impacts, floodplain encroachment, stream relocation, impacts to historically significant sites, noise, water quality, and air quality conformity under Clean Air Act amendments. Supplemental EIS triggered by 7% annual growth in air travel demand at Sea-Tac during 1994–1996, with 1996 aircraft operations (395,200) exceeding Master Plan Update forecast for year 2005. SEPA and NEPA combined document; third step of phased environmental review following 1992 Flight Plan Final EIS and 1996 Final EIS. Responsible Federal Official: Dennis Ossenkop, FAA. SEPA contact: Barbara Hinkle, Port of Seattle. Signed by Lowell H. Johnson, Manager, Northwest Mountain Region Airports Division, dated 5/13/97.