TagNEPA(463)

The Port of Seattle is conducting an environmental review of near-term construction projects at Seattle-Tacoma International Airport (Sea-Tac) planned through 2027, as part of the Sustainable Airport Master Plan (SAMP). Key planned improvements include a second terminal, a centralized maintenance campus, off-airport cargo facilities, and roadway and fueling expansions to accommodate up to 477,000 annual flights and 56 million passengers. A full Environmental Impact Statement (EIS) under Washington State's SEPA, as well as a federal Environmental Assessment under NEPA led by the FAA, are being prepared to evaluate potential environmental impacts.

This scoping information packet, prepared by Landrum & Brown, Inc. for the Port of Seattle in July 2018, outlines the environmental review process for near-term projects under the Seattle-Tacoma International Airport Sustainable Airport Master Plan. It initiates the scoping phase, during which public and agency input is gathered to identify key environmental issues to be studied. The document serves as a foundational reference for understanding the scope and potential impacts of planned airport development projects.

This 2018 FAA memorandum explains how a special environmental review shortcut—called a Categorical Exclusion (CATEX 1)—can be used to streamline approval of certain GPS-based flight procedures (RNAV/RNP) at major airports, including core hub airports like Sea-Tac, without requiring a full environmental impact study. The exclusion applies unless officials determine that extraordinary circumstances exist that could cause significant environmental harm, such as notable noise impacts on surrounding communities. Specific documentation and approval from FAA environmental and legal offices are required before the exclusion can be applied.

This document presents a community challenge to the FAA's environmental review (CATEX) of new flight routes near Seattle-Tacoma International Airport, arguing that the FAA's own noise analyses show significant noise increases in the surrounding General Study Area that exceed the agency's own significance thresholds. The authors contend that the FAA could not rely on the outdated 2013-2018 Port of Seattle Part 150 noise study, and that the FAA's independent analyses revealed noise level jumps ranging from 5.2% to nearly 60% across various decibel contours. The document concludes that the FAA's declaration of 'no noise impacts' is implausible given data showing that portions of previously quiet neighborhoods now experience non-compatible land use noise levels above 65 dB DNL.

This April 2018 Federal Aviation Administration document describes a proposed procedural change at Seattle-Tacoma International Airport to automatically direct southbound turboprop aircraft to a 250-degree westerly heading during north-flow operations between 6 am and 10 pm, rather than requiring air traffic controllers to manually coordinate each turn. The nighttime hours of 10 pm to 6 am were excluded from the automatic turn procedure in response to community concerns from the City of Burien and other residents about flight noise over sensitive areas. The document evaluates this preferred alternative alongside other options, including changes to heading angles and missed approach procedures, which were ultimately eliminated due to safety and airspace separation requirements.

Four cities near Sea-Tac Airport — Burien, Des Moines, Normandy Park, and SeaTac — entered into a formal interlocal agreement in 2018 to coordinate their review of the Port of Seattle's Sustainable Airport Master Plan (SAMP), a 20-year airport growth proposal with potential significant noise and environmental impacts on surrounding communities. The agreement establishes a shared process for hiring consultants, pooling funding, and submitting unified comment letters during the NEPA and SEPA environmental review processes. It covers the period from March 2018 through December 2020 and is governed by Washington State's Interlocal Cooperation Act (RCW 39.34).

The cities of Burien, Des Moines, Normandy Park, and SeaTac entered into a formal interlocal agreement to coordinate their review of the Port of Seattle's Sustainable Airport Master Plan (SAMP), which outlines airport growth over the next 20 years. The agreement establishes a shared process for hiring and funding consultants, issuing joint comment letters, and responding to environmental documents produced under NEPA and SEPA. Contract administration is led by the City of SeaTac, while fiscal management is handled by the City of Burien.

The cities of Burien, Des Moines, Normandy Park, and SeaTac entered into an interlocal agreement to coordinate their review of the Port of Seattle's Sustainable Airport Master Plan (SAMP), which outlines airport growth over the next 20 years. The agreement establishes a process for the four cities to jointly analyze environmental impacts, submit coordinated comments under NEPA and SEPA, and potentially hire shared consultants to assist with their response. Approved by the Burien City Council on February 5, 2018, the agreement aims to give the neighboring cities a stronger, unified voice in evaluating potential negative impacts from Sea-Tac Airport expansion.

This 2017 Noise Technical Report, prepared by The Greenbusch Group for the Washington State Department of Transportation, evaluates the noise impacts of Phase 1 of the SR 509 Completion Project near Seattle-Tacoma International Airport. It compares the proposed highway improvements against a 2003 environmental impact study, assessing changes in noise levels, affected residents, and noise abatement measures such as sound walls. The report concludes with recommendations for minimizing construction and long-term traffic noise impacts on surrounding communities.

This October 2017 Technical Memorandum, prepared by Leigh Fisher for the Port of Seattle, outlines development alternatives for Seattle-Tacoma International Airport as part of its Sustainable Airport Master Plan. It covers a wide range of potential airport improvements, including airfield capacity enhancements, passenger terminal expansion, ground access and parking, air cargo facilities, and general aviation. The document evaluates options such as runway relocations, new taxiway configurations, and midfield terminal development to meet long-term aviation demand.