I-90 Snoqualmie Pass East, Mile Post 55 to 71 (Hyak to Keechelus Dam), Kittitas County, WA

URS for the Washington State Department of Transportation

White Shield is providing on-call survey and mapping support to URS and WSDOT for the design of expanding I-90 to 6-lanes between Hyak and Keechelus Dam in Kittitas County. In 2003, White Shield completed a 15 mile ROW Retracement Survey that included this segment. Tasks completed in 2006 under the current contract include the horizontal and vertical location of 48 boreholes for inclinometers and extensometers, establishment of 170 Sirovision camera reference points, establishment and monthly monitoring of 15 points for deformation surveys, staking 5,600 feet of design slope catch line for geotech review, locating 200’ of headscarps, locating additional wetland and talent ditch sites, 3 bridge deck detail surveys, and 5 culvert/bridge surveys. In 2007, 6 miles of topographic mapping was provided in the areas of Crystal Springs, Keechelus Lake, Gold Creek, Mardee Lake and Townsend Creek; an additional 13,000 feet of catch line was staked and a 3-mile utility survey was performed. 83 additional boreholes were located to facilitate geotech review for the alignment feasibility study. Support for the geotech work has continued each summer through 2010. Additional work has includedstructural wall staking, 100+ borehole locations, test pit locations, Sirovision control, an additional 8700’ of catch line staking, continued deformation point monitoring, and other miscellaneous support tasks. Continued wetland tasks supporting the URS Wetland Specialist have included additional topographic surveys at the Gold Creek stockpile site, Wolfe Creek, Resort Creek, Townsend Creek, Sunset Highway, the Crystal Springs Campground, and an un-named creek at MP 57.

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