Challenge

Loreto Plaza, a former farmland that was converted into a commercial shopping center, faced significant environmental concerns due to contamination from historical dry cleaning operations dating back to the 1960s. The presence of chlorinated solvents like tetrachloroethene (PCE) had resulted in soil and groundwater contamination, raising the potential risk of indoor vapor intrusion affecting nearby residents and commercial tenants. The client sought a solution to mitigate health risks, resolve soil and groundwater impacts, and address potential legal liabilities.

Solutions

GLA applied its extensive water resources and environmental consulting expertise to investigate the site, conducting a comprehensive vapor intrusion risk assessment. In accordance with California Environmental Protection Agency (CalEPA) guidance, we assessed the potential for PCE volatilizing from groundwater and impacting surrounding areas. Our team installed subsurface vapor monitoring probes and conducted detailed soil testing to evaluate vapor intrusion risks and volatile organic compound (VOC) concentrations. Our findings, backed by site-specific modeling and extensive monitoring, demonstrated that vapor mitigation was not necessary for the site despite the presence of VOCs, which allowed the client to avoid costly mitigation measures. We also implemented a semi-annual monitoring program and worked with the Regional Water Quality Control Board (RWQCB) to develop a long-term plan for remediation.

Results

GLA’s expertise in groundwater and vapor intrusion management provided critical insights that reduced the client’s legal and environmental risks. Our work led to the successful evaluation and management of the groundwater VOC plume, minimized unnecessary remediation costs, and established a path for long-term site cleanup. Through ongoing monitoring and a tailored public participation program, we ensured community engagement and regulatory alignment.

I have worked with many contamination ‘experts’ over the years, specifically since 1985 when I made it a predominant niche in my law practice. DBS&A is the best of them: prompt, diligent, accurate, and above all, absolutely up to date in every detail with respect to methodology, cost benefit analysis, and the meaning and effect of the ever changing regulatory guidelines set by the State of California and the federal government—and that says a lot.”

Mr. John DeLoreto, Attorney at Law