Pre-Purchase Due Diligence and Vapor Intrusion Assessment

TRC assisted the Salmon Bay Eagles (Eagles) with potential pre-purchase due diligence of their property. That due diligence identified the property as a historical service station. The underground storage tanks (USTs) had been closed in place in 1989 with no follow-up assessment. Follow-up geophysical investigation identified the presence of three abandoned USTs and apparent dispenser piping. Further assessment of the property identified impacts to soil and groundwater, including light non-aqueous phase liquid (LNAPL) migrating off-property.

TRC assisted the Eagles with an evaluation of potential vapor intrusion risks to potential future tenants through sub-slab and indoor air sampling. TRC determined that the potential impacts would not result in unacceptable risks using a risk-based exposure model for commercial site workers.

TRC also assisted the Eagles in support of a private right-of-action to recover past and potential future costs related to the contamination on the property. The prior service station operator was a major oil company, which retained significant liability for the contamination. TRC prepared cost estimates for a range of remedial options that addressed the specific issues at the property such as its relatively small size, limited access, and off-property contaminant migration. TRC also participated in and supported the Eagles’ negotiations with the major oil company and assisted counsel in the preparation of various claims and demands. This project is ongoing.