COMMISSION AGENDA MEMORANDUM BRIEFING ITEM Item No. Date of Meeting 11a October 28, 2025 DATE: October 17, 2025 TO: Stephen P. Metruck, Executive Director FROM: Sarah Cox, Director, Aviation Environment and Sustainability Steve Rybolt, Senior Environmental Program Manager, Aviation Environment and Sustainability SUBJECT: Sustainable Airport Master Plan Near-Term Projects Final National Environmental Policy Act Environmental Assessment, Federal Aviation Administration Finding of No Significant Impact, Record of Decision, and State Environmental Policy Act Next Steps EXECUTIVE SUMMARY On October 14, Port Staff provided an overview of the Federal Aviation Administration's (FAA) Finding of No Significant Impact (FONSI) and Record of Decision (ROD) based on the outcome of the Final National Environmental Policy Act (NEPA) Environmental Assessment (EA) of the Sustainable Airport Master Plan (SAMP) Near-Term Projects (NTP). At the Commission's October 28 meeting, staff will provide a short update on the public outreach and engagement that has occurred since the FAA's documents were released, as well as an update on next steps for the State Environmental Policy Act (SEPA) process. DETAILS The FAA has completed the NEPA Final Environmental Assessment (FEA) of the SAMP NTPs and has issued a Finding of No Significant Impact (FONSI) and Record of Decision (ROD). The FEA was informed by a 53-day public comment period in 2024. The document is the result of rigorous analysis, extensive public outreach and engagement, reviewing, considering, and responding to comments submitted by the community and public agencies. It is important to note that in between the closure of the public comment period and the publication of the FEA the Administration implemented regulatory changes that removed analysis on environmental justice, climate, and cumulative impacts. Based on the analyses within the Draft and Final NEPA EA, it was identified that all significant impacts could be mitigated. There were other impacts identified; however, these impacts did not exceed regulatory, or human health standards and FAA does not require any defined action to reduce, avoid, or mitigate them. Based on the information and analysis contained in the Final NEPA EA, the FAA issued a FONSI ROD on September 24, 2025 (published on September 26, 2025), identifying 18 requirements that the Port must adhere to should any of the NTPs move Template revised April 12, 2018. COMMISSION AGENDA - Briefing Item No. 11a Meeting Date: October 28, 2025 Page 2 of 3 forward. The Final NEPA EA and ROD are published on the project website (www.sampntpenvironmentalreview.org) and physical copies are available at Port of Seattle SeaTac Airport Office (Mezzanine Level), Port of Seattle Pier 69 Office, Burien Library, Des Moines Library, Federal Way, Valley View Library (SeaTac), White Center Library, Tukwila Library, and Vashon Library. In February 2019, Port Staff confirmed that SEPA would commence following the completion of NEPA. This was a result of the Port wanting to better understand how human health and ultrafine particulate matter consideration might be incorporated into SEPA, as these are not typically evaluated in NEPA. The other resource categories that were removed by FAA from the NEPA documentation due to recent Administration regulatory changes will be moved into the Port's work under SEPA. This includes Environmental Justice, Climate, and Cumulative Impacts. It is anticipated that a Draft SEPA Environmental Impact Statement (EIS) will be released in late first quarter of 2026, followed by a public comment period. The Port will provide a thorough and broad outreach and engagement program in support of the publication of the Draft SEPA EIS. This includes work to engage a variety of communities and using a range of media outlets, information on the project website, community meetings, interpretation and translating materials into additional languages. Once the public comment period closes, the Port will review and respond to the comments received. These comments will be considered within Final SEPA EIS. It is expected that the Final SEPA EIS will be published in late 2026. SCHEDULE NEPA September 26, 2025 (Published) SEPA Quarter 1 2026 Quarter 4 2026 FAA NEPA Final EA and Record of Decision Draft SEPA EIS released for public comment (minimum 30-day comment period [standard]) SEPA EIS Final Document & Determination (Port issues decision document) ATTACHMENTS TO THIS BRIEFING (1) Presentation slides Template revised September 22, 2016. COMMISSION AGENDA - Briefing Item No. 11a Meeting Date: October 28, 2025 Page 3 of 3 PREVIOUS COMMISSION ACTIONS OR BRIEFINGS October 14, 2025 - Commission Briefing: "Sustainable Airport Master Plan Near-Term Projects Environmental Review" October 22, 2024 - Commission Briefing: "Sustainable Airport Master Plan Near-Term Projects Environmental Review - Draft NEPA Environmental Assessment Findings and Public Comment Period" June 27, 2023 - Commission Action: "Sustainable Airport Master Plan (SAMP) Near-Term Projects Environmental Review - Update and Budget Increase" February 25, 2020 - Commission Action: "Sustainable Airport Master Plan (SAMP) Near-Term Projects (NTP) Environmental Review Briefing and Request for Additional Funds" January 28, 2020 - Commission Briefing: "Sustainable Airport Master Plan (SAMP) Near-Term Projects (NTP) Environmental Review Briefing - Forecast and Schedule Update" February 26, 2019 - Commission Briefing: "Sustainable Airport Master Plan (SAMP) NearTerm Projects (NTP) Environmental Review Briefing - Scoping Report" May 8, 2018 - Commission Briefing: "Sustainable Airport Master Plan (SAMP) Planning and Environmental Update" February 13, 2018 - Commission Briefing: "Sustainable Airport Master Plan (SAMP) Planning Update" Template revised September 22, 2016.