Notes
SEPA public comment filed by Jeff Bogen, Des Moines, WA resident and member of the Des Moines Airport Advisory Committee, regarding the Seattle-Tacoma International Airport (SEA) Sustainable Airport Master Plan (SAMP) SEPA Draft Environmental Impact Statement (DEIS). The comment presents event-based analysis of aircraft noise exposure using Sound Exposure Level (SEL) records from Port Of Seattle noise monitors SEA12, SEA13, SEA17, SEA18, and SEA19 spanning March 12–April 9, 2026. Documents 529 noise events per day at SEA18 with a 1.5-minute median inter-event gap; 91.2% of intervals below 5 minutes; 89 nighttime events (22:00–07:00) per night. Applies DEIS Appendix A Table 6 projection of 475,655 annual operations under the 2032 Proposed Action (+9.1% above 2025 baseline of 435,896) to project 577 daily events and 97 nightly events by 2032. Argues the DNL 65 dB metric and DNL-only analysis fails to disclose cumulative impacts under WAC 197-11-330 and WAC 197-11-794. Cites WHO Lnight guidelines, Basner et al. 2023, Neimann et al. 2013, and Baczalska et al. 2022 on cardiovascular and sleep health effects of aircraft noise event frequency.