Notes
January 14, 2002 letter from attorney Kevin L. Stock of Helsell Fetterman LLP to Col. Ralph Graves, Ms. Muffy Walker, and Ms. Gail Terzi of the U.S. Army Corps of Engineers Seattle District, transmitting GeoSyntec Consultants comments on Hart Crowser’s November 4, 2001 Geotechnical Summary Report for the Third Runway Embankment Fill and West MSE Wall, Seattle-Tacoma International Airport Project (Corps Ref. No. 1996-4-02325). On behalf of the Airport Communities Coalition (ACC), the letter highlights the Port of Seattle’s radical shift from in situ ground improvement (stone columns) to excavation and replacement of up to three million cubic yards of material below the proposed MSE wall, raising concerns about dewatering impacts on Miller Creek and adjacent wetlands under CWA Section 404. GeoSyntec identifies technical deficiencies in seismic loading and stability analyses, misleading claims about Mechanically Stabilized Earth (MSE) wall seismic design, and undocumented stone column testing results. ACC requests Corps investigation of potential Clean Water Act violations from 100 stone columns installed at the site.