TagEnvironmental Impact Statement(325)

This appendix from Seattle-Tacoma International Airport's Final Supplemental Environmental Impact Statement evaluates potential environmental impacts through the year 2020 under three scenarios, including the new Port forecast and cases where aviation demand grows 10% faster than projected. Key findings indicate that noise impacts are expected to remain below current levels in all scenarios, with 'With Project' improvements producing roughly 53% of current noise conditions by 2020. The analysis also examines air quality, enplanement levels, and aircraft operations across both Do-Nothing and preferred alternatives to guide long-term airport planning.

This technical report supplements the Final Environmental Impact Statement for Seattle-Tacoma International Airport's Master Plan Update, focusing on construction impacts related to the proposed Third Runway and associated projects. It analyzes fill material requirements estimated at 17.25 million cubic yards, haul routes, and truck traffic volumes, noting that the construction timeline was extended from three to five years, which reduced the number of average daily truck trips compared to earlier estimates. The report examines both on-site and off-site material sources and assesses potential traffic congestion impacts on regional roadways during the construction period.

This 1997 Final Supplemental Environmental Impact Statement evaluates the environmental effects of proposed expansion projects at Seattle-Tacoma International Airport, including construction of a new 8,500-foot third parallel runway, terminal improvements, and expanded parking and cargo facilities. The document examines potential impacts such as wetland disturbance, floodplain encroachment, stream relocation, and air, water, and noise quality effects on surrounding communities. It was prepared jointly under the National Environmental Policy Act and Washington State Environmental Policy Act to address concerns arising from continued growth in aviation activity levels.

Comments submitted by the Airport Communities Coalition—comprising the cities of Burien, Des Moines, Federal Way, Normandy Park, Tukwila, and Highline Public Schools—on the Draft Supplemental Environmental Impact Statement for the proposed Master Plan Update Development Actions at Seattle-Tacoma International Airport. The document was prepared by Cutler & Stanfield, L.L.P. as counsel to the coalition, in

This 1997 document argues that the Port of Seattle's Environmental Impact Statement (EIS) for a proposed third runway at Sea-Tac Airport inadequately examines impacts on wetlands and fails to prescribe sufficient mitigation measures. It contends that the FAA and Port must meet federal and state legal requirements — including Section 404 of the Clean Water Act and Washington's Growth Management Act — before any construction affecting wetlands can proceed. The document asserts that the EIS does not consider a broad enough range of alternatives, making it legally insufficient as a basis for approving the runway project.

A 1997 study commissioned by cities and institutions near Seattle-Tacoma International Airport found that airport operations depress nearby property values compared to similar homes elsewhere in King County, and that properties directly under flight paths suffer additional losses from noise, visual pollution, and reduced quality of life. Researchers compared single-family homes around Sea-Tac with comparable homes in Northwest King County (Shoreline area), using strict criteria to ensure fair comparisons. The study notes that while overall regional growth means nearby home values may still rise over time, they appreciate more slowly than they would without the airport's presence.

This 1997 draft study assessed the potential environmental, transportation, and socioeconomic impacts of a proposed third runway at Seattle-Tacoma International Airport on five neighboring communities—Burien, Des Moines, Federal Way, Normandy Park, and Tukwila—as well as the Highline School District and Highline Community Hospital District. Funded by a Washington State grant administered through the City of Burien, the study was conducted by a team of consultants and aimed to develop mitigation strategies and funding mechanisms to address impacts on affected jurisdictions. The report reviewed the Port of Seattle's Environmental Impact Statement and proposed independent mitigation measures, while expressly prohibited from being used to oppose the runway's construction.

A handbook by the Council on Environmental Quality providing framework and methods for analyzing cumulative effects in environmental assessments and impact statements under NEPA. The document outlines principles, steps, and data sources for cumulative effects analysis but does not establish new legal requirements.

Letter dated December 18, 1996 from Barbara Hinkle, Senior Environmental Specialist, Port Of Seattle, to Jack Kennedy, U.S. Army Corps of Engineers, Seattle District Office, submitting a Section 404 Application to place fill material into waters of the United States at Seattle-Tacoma International Airport associated with the Master Plan Update. Covers background on the Puget

In December 1996, the Port of Seattle submitted a Section 404 permit application to the U.S. Army Corps of Engineers to place fill material into wetlands at Seattle-Tacoma International Airport as part of its Master Plan Update, which included construction of a third parallel runway. The proposed runway, located 2,500 feet west of the existing runways, was intended to address severe arrival delays during poor weather conditions, which reduced airport capacity from 60 to as few as 24 arrivals per hour roughly 44% of the year. The application was the result of nearly a decade of regional planning, environmental review, and public involvement, including studies confirming that no feasible supplemental airport sites existed in the four-county region.