Remediation Strategies for Residential High-Rise

TRC was retained by a commercial property owner in the Belltown area of Seattle to investigate the lateral and vertical extent of diesel-range organic compounds in soil, groundwater, and indoor air following a release from a home heating fuel tank beneath and adjacent to a large active apartment building. The Client sought TRC’s services after the previous consultants unsuccessfully tried to remediate the site using unnecessarily costly remedial techniques prior to clearly defining a path towards regulatory closure.

TRC used several low-cost, Ecology-accepted strategies to develop alternative cleanup levels that were still protective of human health and the environment. Aquifer testing to determine non-potability of the contaminated aquifer in conjunction with the development of less-stringent MTCA Method B Cleanup Levels were evaluated to allow for substantially less active remediation to achieve closure. While collecting the data necessary to complete the remedial investigation, TRC collected additional data to support that approach, resulting in considerable cost savings to the Client. Low-cost, effective engineering controls were selected to prevent exposure to workers in the basement of the apartment building.