Remedial Action and Upgrade at Ryerson Transit Base - Seattle, WA

Work under the contract consisted of conducting a state-regulated remedial action as well as performing a significant facility upgrade, including: demolishing existing fueling systems; removing underground storage tanks and oil/water separators; excavation and off-site thermal treatment of contaminated soils; and installing new fueling and underground utility systems for King County's Ryerson Transit Base. This base is the primary transit facility serving the City of Seattle and is fully operational seven days a week, twenty-four hours a day. It was important that this schedule not be impacted during the contract performance period.

Specific features of work included: selective demolition of concrete and interior building structures; removal and disposal of eleven underground storage tanks with associated piping and appurtenances; removal of oil/water separators; soil and groundwater sampling and analysis; environmental site and risk assessments; excavation of soils and sludge impacted by fuel oils, PAHs, solvents and methanol; off-site transportation and thermal remediation of approximately 4,000 tons of contaminated soils; design and installation of extensive sub-surface shoring; large scale dewatering of excavations; removal and installation of groundwater monitoring wells; demolition and installation of underground utilities; furnishing and installing new fuel storage tanks and piping; modifying existing structures, and; paving and site restoration.

Project Performance

The winning bid was thirty percent lower than the engineer's estimate and twenty-five percent lower than the second bidder. In addition to being under budget, the project was completed ahead of schedule. King County wrote a letter citing "outstanding performance" and "quality of construction and level of cooperation achieved with the Department of Transportation during performance of this work."