TagSEPA(233)

The City of SeaTac hired the law firm Ogden Murphy Wallace, P.L.L.C. to serve as special environmental counsel, representing the city in the environmental review processes under NEPA and SEPA related to the Port of Seattle's Sustainable Airport Master Plan. The engagement, dated September 10, 2025, also covers any litigation that may arise against the Port or the Federal Aviation Authority in connection with the plan. Legal services are billed at hourly rates ranging from $300 to $535 depending on the level of attorney or staff involved.

The City of Des Moines, Washington, formally requests that the Port of Seattle reject the Determination of Non-Significance (DNS) for the Sea-Tac Airport Flight Corridor Management Program, arguing that it fails to adequately assess impacts on the city's tree canopy and urban forest. City Manager Katherine Caffrey urges the Port to instead conduct a full Environmental Impact Statement (EIS) examining tree removal, urban heat, air quality, stormwater, and habitat effects. The letter emphasizes that Des Moines residents already face disproportionate noise and health burdens from airport traffic, making tree canopy preservation especially critical to their wellbeing.

Appendix K of this environmental review examines socioeconomic conditions, environmental justice, and children's health and safety risks in the area surrounding the proposed project. It finds that 23.3% of the population in the study area is under 18—higher than both King County and statewide averages—and identifies two schools within the project boundary that could expose children to environmental health risks. The appendix also includes an economic impact analysis for the Northwest Seaport Alliance and a separate environmental justice memorandum prepared under Washington State's environmental review process.

The Port of Seattle has issued a Determination of Non-Significance (DNS) under Washington's State Environmental Policy Act (SEPA) for its Flight Corridor Management Program at Seattle-Tacoma International Airport. The program, conducted approximately every five years, identifies and removes trees and other obstructions near the airport's runways that could interfere with flight paths, while also requiring ongoing ecological monitoring and tree replacement. A 15-day public comment period ran through September 11, 2025, after which the Port planned to formally adopt the determination, with any appeals required to be filed in King County Superior Court within 21 days of formal adoption.

The Port of Seattle's Flight Corridor Management Program is an ongoing effort to identify and remove trees near Seattle-Tacoma International Airport (SEA) that obstruct the flight paths of its three parallel runways, as required by FAA regulations. Approximately every five years, the Port surveys the area, removes obstructing trees, and replants replacements, with each cycle documented in publicly available Implementation Plans and Regulatory Memoranda. This 2025 programmatic environmental review under Washington's State Environmental Policy Act (SEPA) covers the long-term program rather than individual removal projects.

The National Marine Fisheries Service (NMFS) issued a Biological Opinion on July 28, 2025, in response to a Federal Aviation Administration consultation request regarding near-term construction projects outlined in the Seattle-Tacoma International Airport Sustainable Airport Master Plan. The opinion evaluates potential effects of these projects on endangered species and critical fish habitat under the Endangered Species Act and the Magnuson-Stevens Fishery Conservation and Management Act. NMFS reviewed and independently verified analyses from the FAA's Biological Evaluation, incorporating findings related to the proposed action area, species status, and effects on critical habitat.

The Port of Seattle is proposing upgrades to Seattle-Tacoma International Airport's Industrial Wastewater Treatment Plant (IWTP) to better handle wastewater from aircraft deicing operations, with construction planned from 2026 to 2030. The project involves replacing aging treatment equipment at the existing facility and building a new aerated gravel bed (AGB) treatment system on a 10.6-acre site nearby to process high levels of biochemical oxygen demand (BOD) on-site. These upgrades are required to comply with tightening discharge limits set by King County and state environmental permits.

WSP conducted a wetland verification study in May 2025 to confirm the accuracy of a 2022 wetland delineation near the Seattle-Tacoma International Airport's Industrial Wastewater Treatment Plant (IWTP), which is being expanded to increase treatment capacity and meet permit requirements. The study assessed three previously identified wetlands — IWS-A, IWS-B, and WL28 — all located within the Lagoon 3 Study Area, ranging in size from 0.54 to 29.7 acres. The verification was conducted to ensure the existing delineation boundaries remain valid for environmental permitting purposes ahead of planned construction.

Washington State Substitute House Bill 1303 requires the Department of Ecology to add environmental justice as a formal element of environmental review under the State Environmental Policy Act (SEPA), including updates to environmental checklists and impact assessments. The bill directs the agency to develop standardized mitigation measures for potential environmental justice impacts, which must be factored into project threshold determinations. These new requirements are intended to reduce disparate environmental and health burdens on overburdened communities across Washington State.