Partner’s LEPs completed a site investigation in accordance with the DEEP’s Site Characterization Guidance Document (SCGD) and determined the chlorinated solvents had been released to shallow bedrock immediately beneath a 300,000 SF building. Partner’s LEP also identified a release of waste oil to soil and bedrock beneath a chip pit, and a release of PCBs from a power transformer. Partner’s LEP designed and installed a high flow Soil Vapor Extraction System (SVE) to remove chlorinated solvents from the bedrock interface beneath the building, excavated petroleum off of the bedrock surface, power washed the undulating bedrock surface, and excavated PCB releases.
The site is surrounded by 27 private drinking water wells. Partner demonstrated that the wells were unaffected by releases at the site through sampling, analysis, and hydrogeological evaluation. While the wells were unaffected by releases at the site, the regulations require protection of existing use (i.e. drinking water supply). As a result, the SVE system was installed and operated to remove the chlorinated solvents to the maximum extent prudent to protect existing uses. The remediation activities were effective in meeting compliance with the Remediation Standard Regulations (RSRs)(§22a-133k 1 through 3) for soil, and reducing contaminant concentrations in bedrock groundwater to below the drinking water standards. Since sensitive ecological receptors are located on-site and adjacent, Partner’s LEP completed an ecological risk assessment and determined that no ecological significant risk existed with respect to contaminant releases at the site.
At the conclusion of compliance groundwater monitoring, Partner submitted an LEP Verification report to DEEP for work completed at the site. DEEP issued a No Audit Letter in response.
