This document presents a community challenge to the FAA's environmental review (CATEX) of new flight routes near Seattle-Tacoma International Airport, arguing that the FAA's own noise analyses show significant noise increases in the surrounding General Study Area that exceed the agency's own significance thresholds. The authors contend that the FAA could not rely on the outdated 2013-2018 Port of Seattle Part 150 noise study, and that the FAA's independent analyses revealed noise level jumps ranging from 5.2% to nearly 60% across various decibel contours. The document concludes that the FAA's declaration of 'no noise impacts' is implausible given data showing that portions of previously quiet neighborhoods now experience non-compatible land use noise levels above 65 dB DNL.Open full document
Notes
This document critiques the FAA’s noise analyses contained in a CATEX (Categorical Exclusion), arguing that FAA’s own data shows significant noise increases within the General Study Area that exceed the 1.5 dB DNL significance threshold. The author contends that the FAA cannot rely on the outdated SEA Part 150 Study and that the noise levels in the area were far higher than previously documented, reaching 65 dB DNL compared to the 40-45 dB DNL shown in the 2013-2018 Part 150 Study. An associated email from Sharyn Parker to Susan Plecko and Linda E. Schwaber discusses strategy for appealing the CATEX findings.