Interim Measures at Commercial TSDF
Following a large explosion and fire at this commercial permitted RCRA TSDF, Cox-Colvin implemented Interim Measures (IMs) through the RCRA Corrective Action program to rapidly assess conditions and implement final remedies. The explosion and fire resulted in the destruction of much of the facility and the release of various liquids (primarily solvents) which entered surface water, subsurface soil, perched groundwater, and the regional sole source aquifer.
IMs were conducted over an 18 month period which began immediately upon gaining access to the facility following emergency response actions. Two separate IMs were conducted. The first involved an unlined stormwater retention basin which received runoff from the tank farm and fire-fighting water and chemicals. The unlined retention basin acted as a direct pathway to groundwater and the sole source aquifer. Working closely with the state EPA and emergency responders, Cox-Colvin performed an expedited evaluation of available remedial technologies and implemented a groundwater containment system followed by the application and recirculation of a chemical oxidant. Within several weeks of access, recovery wells were designed, installed, and placed online at a combined pumping rate of approximately 40 gpm. A chemical oxidant was then added to the retention basin in a series of applications and allowed infiltrate downward to groundwater. The recovery wells were then used to recirculate the chemical oxidant in the vadose zone and groundwater. Within approximately four weeks, the recovery wells were taken offline. Confirmation groundwater and vadose zone sampling demonstrated that no further action was required.
Following the demolition of the operations area, Cox-Colvin conducted rapid characterization of the nature and extent of contamination beneath the operations area and performed a detailed, but rapid, evaluation of remedial alternatives, consistent with the approach that is typically employed during a CMS. Following approval of the IM, Cox-Colvin implemented the excavation and offsite disposal of approximately 40,000 cubic yards of vadose zone soil, to depths as great as 40 ft. Green and sustainable remediation principals were utilized in the design and implementation of the remedy.