TagMechanically Stabilized Earth(42)

This engineering cross-section diagram from Sea-Tac International Airport illustrates the dramatic 179-foot elevation drop adjacent to the proposed Third Runway, showing how a massive retaining wall and new embankment would be constructed alongside Miller Creek. The exhibit depicts key infrastructure features including a permanent chain-link security fence, rock underdrain, silt fence, inner collection swale, and a minimum 50-foot creek buffer zone designed to protect the existing waterway. The drawing is part of the Miller Creek Instream and Buffer Enhancements project documentation associated with the Third Runway expansion.

This engineering study describes the design and construction of a 46-meter (150-foot) tall mechanically stabilized earth (MSE) retaining wall built along the western edge of Seattle-Tacoma International Airport's third runway embankment, believed to be the tallest such wall in the western hemisphere at the time. The wall was necessary to raise the ground level by up to 50 meters while avoiding encroachment into nearby wetlands and creeks. Monitoring of the wall during and after construction confirmed it performed safely and largely as predicted.

Prehearing brief filed by appellant Airport Communities Coalition (ACC) and intervenor-appellant Citizens Against Sea-Tac Expansion (CASE) in PCHB No. 01-160, appealing the Washington Department of Ecology’s August 10, 2001 Section 401 Clean Water Act certification for the Sea-Tac Airport Third Runway project. Documents the Port of Seattle’s proposal to fill a canyon with 20 million

This document examines the geotechnical effects of the February 28, 2001 Nisqually earthquake on earth structures in the Olympia, South Seattle, and Tacoma, Washington area. It covers damage observations including landslides along Highway 101, failures of road and railroad embankments, performance of mechanically stabilized earth retaining walls, and the condition of solid waste landfills following the quake. One notable slide near the State Road 8 junction involved a 15-20 meter high embankment that collapsed and sent debris flowing approximately 150 meters downslope.

Pre-filed testimony submitted to the Environmental Hearings Office (Pollution Control Hearings Board, PCHB No. 01-160) on behalf of appellant Airport Communities Coalition (ACC) in ACC & CASE v. Dept. of Ecology & Port of Seattle. Testimony by Amanda Azous (wetlands) and Dr. Edward Kavazanjian (geotechnical), filed February 22, 2002. Binder 1 of 4 index lists

Draft memorandum dated January 17, 2002 from Hart Crowser engineers Doug Lindquist, Reda Mikhail, and Michael Bailey to Jim Thomson (HNTB Corporation), project number 4978-40, regarding FLAC (finite difference model) seismic analysis of three proposed mechanically stabilized earth (MSE) retaining walls for the Third Runway project at Seattle-Tacoma International Airport. Analyses cover four wall sections

Memorandum dated January 11, 2002, from Michael Bailey P.E. and Barry Chen P.E. of Hart Crowser, Inc. to Jim Thomson P.E. of HNTB Corporation, regarding geotechnical design parameters for Third Runway MSE (Mechanically Stabilized Earth) wall design at Sea-Tac Airport. Document AR 053235-053237 covers minimum factors of safety for static and seismic stability per 1996-2000

Memorandum dated January 9, 2002, from Barry S. Chen, P.E., and Michael Bailey, P.E., Hart Crowser, Inc., to Jim Thomson, P.E., HNTB (project 4978-30), reviewing RECo 30% design for NSA, West, and South/MSE walls of the Sea-Tac Third Runway Embankment Project. Hart Crowser performed independent limit equilibrium analyses (SLOPE/W) and FLAC finite difference modeling to