Notes
Port of Seattle SEPA Determination of Non-Significance (DNS), POS SEPA File No. 2025-05, issued August 21, 2025, for the Flight Corridor Management Program at Seattle-Tacoma International Airport (SEA). The Program identifies and removes obstructions — primarily trees — within and around Runway Protection Zones for runways 34R/16L and 34L/16R, extending 1,500 feet east/west and 3,500 feet north/south beyond the outer limits of those zones. Program Area includes Port-owned properties and public/private lands in the cities of Burien, SeaTac, and Des Moines, plus properties owned by WSDOT and Highline School District. The Port determined no Environmental Impact Statement (EIS) is required under RCW 43.21C.030(2)(c). Public comment period closes September 11, 2025 at 4:00 PM. Signed by Sarah Cox, Director of Aviation Environment and Sustainability, as SEPA Responsible Official. Appeals must be filed in King County Superior Court within 21 days of formal adoption pursuant to Port of Seattle Resolution No. 3650 and RCW 43.21C.080. Contact: Steve Rybolt, 206.787.5527, SEPA@portseattle.org.