TagNEPA(463)

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.

Environmental Science Associates hosted a webinar examining rapid changes in federal environmental permitting, covering topics such as streamlined categorical exclusions under NEPA, cultural resources consultation under Section 106, and the growing use of AI tools in environmental review workflows. Experts noted that agencies face increasing pressure to accelerate infrastructure permitting timelines while maintaining legally defensible documentation, particularly as recent court decisions and regulatory rescissions create greater agency discretion and less standardized guidance. Organizations are advised to invest in adaptable workflows and early interagency coordination to manage permitting risk in this shifting landscape.

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.

This report analyzes existing traffic conditions around Seattle-Tacoma International Airport as part of the Sustainable Airport Master Plan (SAMP) Near-Term Projects Environmental Review. It examines 108 intersections—including signalized, stop-controlled, and uncontrolled locations—along key travel routes connecting the airport to surrounding communities, focusing on weekday PM peak hour traffic volumes. The study also includes freeway analysis of SR 518 and I-5 ramps and segments at the request of WSDOT.