TagSEPA(71)

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.

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.

The Port of Seattle submitted an environmental checklist in January 2025 for a limited update to Seattle-Tacoma International Airport's Water System Plan, covering the period 2025–2028. The update addresses routine maintenance and infrastructure improvements to SEA's drinking water and fire protection system, including pipe replacements, new surge tanks, additional water storage, and a backup water supply connection to Highline Water District. Washington State Department of Health approval and Port of Seattle Commission adoption are required before the plan can be implemented.

HB 1303 is a Washington State bill focused on environmental justice, not Sea-Tac Airport noise policy. It proposes adding environmental justice considerations to the State Environmental Policy Act (SEPA) review process and prohibiting certain air pollution permits in overburdened communities. This document does not contain relevant content for a Sea-Tac Airport noise policy archive.

Washington Senate Bill 5380 (2025) requires state agencies to evaluate environmental justice impacts when reviewing permits for industrial or potentially harmful projects located in pollution-burdened communities. It mandates the completion of an Environmental Justice Impact Statement and a public hearing within affected communities before project approvals can move forward. The bill aims to reduce cumulative environmental and health disparities across Washington State.

Four cities near Sea-Tac Airport — Burien, Des Moines, Normandy Park, and SeaTac — have joined together under a formal interlocal agreement to coordinate their review of the Port of Seattle's Sustainable Airport Master Plan (SAMP), which could bring significant noise and environmental impacts to surrounding communities over the next 20 years. The agreement establishes a shared process for hiring consultants, submitting joint public comments, and responding to environmental documents produced under federal (NEPA) and state (SEPA) law. The collaboration is set to run through December 31, 2027, with the City of Des Moines managing consultant contracts and the City of Burien overseeing fiscal matters.

The FAA released a draft Environmental Assessment in October 2024 for Seattle-Tacoma International Airport's Sustainable Airport Master Plan (SAMP), which outlines 31 near-term projects to expand airport capacity for growing passenger demand. Key projects include a new passenger terminal and gates, taxiway extensions, cargo facility changes, and employee parking updates. The cities of SeaTac, Burien, Des Moines, and Normandy Park are collaborating to submit technical comments on the plan before the December 13, 2024 deadline.

This appendix from the Puget Sound Regional Council's long-range transportation plan, Destination 2030, outlines the process for amending the plan and making major capacity investment decisions. It explains that the plan must be reviewed every three years under federal law and every two years under Washington State law, with air quality conformity statements required when amendments are made. The document also provides guidance on evaluating transportation corridor investments, assessing benefits and costs, and classifying projects as either 'Candidate' or 'Approved' for implementation.