The University of Washington purchased approximately 46 acres of commercial and retail properties in downtown Tacoma, Washington, for a branch campus. Pre-purchase Level I environmental site assessments indicated some parcels could contain subsurface contamination. CDM conducted subsurface investigations, developed risk-based cleanup standards in accordance with Washington's Model Toxics Control Act, and remediated the contaminated properties.
Site investigations included drilling soil borings, installing groundwater monitoring wells, and collecting soil and groundwater samples for chemical testing. Based on the testing results, CDM developed cleanup action plans for those areas requiring remediation. Full design documents, including plans and specifications and engineer's cost estimates, were prepared for public bidding.
Site work included monitoring demolition of a building containing asbestos and lead-base paint materials, installation of temporary earth shoring for excavation of hydrocarbon impacted soil, onsite solid-phase treatment of approximately 3,000 yards of hydrocarbon contaminated soil, and extraction and treatment of contaminated groundwater.