TagEnvironmental Impact Statement(328)
-
2026-05-22
Appendix O: Agency & Public Engagement
Appendix O is a placeholder section titled 'Agency & Public Engagement,' reserved for public comment and public engagement information that will be included in the final SEPA (State Environmental Policy Act) Environmental Impact Statement. No content has been populated in this draft version. The completed section will document how agencies and the public were involved in the environmental review process. -
2026-05-22
SAMP Near-Term Projects Draft EIS: Chapter 1, Introduction and Purpose & Need
The Port of Seattle is preparing an Environmental Impact Statement (EIS) under Washington State's Environmental Policy Act (SEPA) for 31 near-term construction and improvement projects at Seattle-Tacoma International Airport (SEA). These projects, drawn from the airport's 2018 Sustainable Airport Master Plan, aim to improve passenger facilities, safety, efficiency, and airport access ahead of a projected 2032 completion date. The review follows a completed federal environmental assessment and addresses the region's growing air travel demand while evaluating potential environmental impacts and mitigation measures. -
2026-05-08
Sustainable Airport Master Plan near-term projects environmental review – SEPA draft environmental impact statement and public comment period
The Port of Seattle released a Draft Environmental Impact Statement (DEIS) under the State Environmental Policy Act (SEPA) for the Sustainable Airport Master Plan Near-Term Projects at Sea-Tac Airport, finding that surface transportation is the only category with significant impacts requiring mitigation. The review examined sixteen environmental categories including noise, air quality, and community impacts, with a 60-day public comment period running from May 22 to July 21, 2026, including in-person meetings in SeaTac, Burien, Des Moines, and Federal Way. A final SEPA determination is expected by the end of 2026. -
SAMP Near-Term Projects SEPA Draft EIS Timeline and Next Steps
A project timeline slide showing the environmental review process for a Sea-Tac Airport project, currently at the Draft SEPA EIS Publication stage (5/22/26). Key milestones include the Final NEPA FEA & Decision (9/26/25), Draft SEPA EIS Agency & Public Review, Final SEPA EIS & SEPA Decision (Q4 2026), and Commission Action Required for NTP(s) approval in 2027. -
2026-05-01
Appendix Q: List of Preparers — SEPA EIS and NEPA EA for the Sustainable Airport Master Plan Near-Term Projects
This appendix lists the individuals and organizations responsible for preparing the environmental review documents for Seattle-Tacoma International Airport's Sustainable Airport Master Plan Near-Term Projects. It includes two tables: one covering contributors to the State Environmental Policy Act (SEPA) Environmental Impact Statement, and one listing those who prepared the National Environmental Policy Act (NEPA) Environmental Assessment. Key contributors include staff from the Port of Seattle, consulting firms such as Parametrix, Landrum & Brown, CDM Smith, Concord Engineering, and RS&H, covering areas such as air quality, noise, climate change, safety, and biological resources. -
2026-05-01
Draft Environmental Impact Statement for the Sustainable Airport Master Plan Near-Term Projects
The Port of Seattle has released a Draft Environmental Impact Statement (EIS) under Washington State's environmental review law for 31 near-term construction projects at Seattle-Tacoma International Airport (SEA). The projects, which include a new 19-gate terminal and an elevated busway system, are designed to handle up to 56 million passengers by 2032. While a prior federal review found no significant environmental impacts requiring mitigation except for surface transportation, this state-level review evaluates two action alternatives alongside a no-action scenario. -
2026-05-01
Draft EIS Summary: Seattle-Tacoma International Airport SEPA Environmental Impact Statement for the Sustainable Airport Master Plan Near-Term Projects
The Port of Seattle has released a Draft Environmental Impact Statement for its Sustainable Airport Master Plan (SAMP), outlining 31 near-term construction projects at Seattle-Tacoma International Airport aimed at handling a projected 56 million passengers by 2032. Key proposals include a second terminal with 19 new aircraft gates, an elevated busway connecting terminals, expanded cargo facilities, airfield safety upgrades, and new sustainable aviation fuel infrastructure. The plan addresses longstanding capacity shortfalls in parking, check-in, security, and gate areas that were already undersized as of 2018. -
2026-05-01
Seattle-Tacoma International Airport SEPA Environmental Impact Statement for the Sustainable Airport Master Plan Near-Term Projects: Chapter 2 — Alternatives
This draft Environmental Impact Statement (EIS) evaluates proposed expansion projects at Seattle-Tacoma International Airport under Washington State's Environmental Policy Act (SEPA). It outlines a two-step screening process used to assess alternatives, including suggestions from public scoping such as building a new airport, using other transportation modes, and limiting growth — most of which were rejected for failing to meet the project's purpose of serving 56 million annual passengers at an optimal level of service. A No Action Alternative is also included, representing a future baseline without the proposed physical improvements. -
2026-05-01
Chapter 3: Affected Environment — Seattle-Tacoma International Airport SEPA Environmental Impact Statement for the Sustainable Airport Master Plan Near-Term Projects
This section of the Draft Environmental Impact Statement (EIS) for Seattle-Tacoma International Airport's Sustainable Airport Master Plan describes the existing environment surrounding the airport, which sits on approximately 2,800 acres in SeaTac, Washington, about 12 miles south of downtown Seattle. The study area covers roughly 3,692 acres bounded by nearby cities including Burien, Des Moines, and Tukwila, where surrounding land use is primarily residential, commercial, and parkland. Baseline environmental conditions are drawn from 2022 data to assess potential direct and indirect impacts of proposed near-term airport development alternatives. -
2026-05-01
SAMP Near-Term Projects Draft EIS: Chapter 4 — Impacts and Mitigation Measures
This draft Environmental Impact Statement (EIS) evaluates the potential environmental effects of near-term construction and expansion projects at Seattle-Tacoma International Airport, comparing a No Action Alternative against two action alternatives through a projected analysis year of 2032, with an out-year assessment extending to 2037. The study examines impacts across multiple environmental categories—including air quality, noise, greenhouse gas emissions, and surface transportation—using forecasted aircraft operations and passenger levels for each alternative. Mitigation and minimization measures are identified to address any significant adverse impacts identified through the analysis.