TagSEPA(293)

A Des Moines, WA resident and airport advisory committee member submitted this public comment to challenge the noise analysis in the Sea-Tac Airport (SEA) expansion environmental review, arguing that the standard Day-Night Average Sound Level (DNL) metric fails to capture how frequently aircraft noise actually occurs in nearby neighborhoods. Using direct measurements from five Port of Seattle noise monitors, the analysis found that some community locations currently experience roughly 529 aircraft noise events per day with a median quiet gap of only 1.5 minutes between them—conditions the commenter projects will worsen by 2032. The submission calls on the Port of Seattle to supplement its environmental review with event-based noise metrics that reflect real community exposure, including nighttime event counts and inter-event recovery time, as required under Washington State's environmental review law (SEPA).

A Des Moines, WA resident and airport advisory committee member submitted this public comment challenging the noise analysis in the Sea-Tac Airport (SEA) expansion environmental review, arguing that the standard Day-Night Average Sound Level (DNL) metric used by the Port of Seattle fails to capture the true burden of aircraft noise on nearby communities. Using direct measurements from Port noise monitors, the analysis found that some locations currently experience around 529 noise events per day with a median gap of only 1.5 minutes between events, conditions projected to worsen significantly under the airport's own growth forecasts. The comment calls on the Port to supplement its environmental review with event-based noise metrics—such as event frequency, quiet-period gaps, and nighttime disturbances—that research links more directly to health impacts like sleep disruption and cardiovascular disease.

Des Moines resident Jeffrey Bogen submitted a formal comment arguing that the Sea-Tac Airport Master Plan (SAMP) Environmental Impact Statement fails to adequately analyze cumulative health effects on nearby communities. He contends that the EIS must go beyond examining individual pollution sources and instead assess the combined burden of aircraft ultrafine particles, roadway traffic emissions, chronic noise, and other stressors together, since scientific research shows these exposures interact and compound one another. Bogen calls for a comprehensive cumulative-risk framework, backed by ten peer-reviewed studies, to be incorporated into the EIS before any accurate public health or policy conclusions can be drawn.