Active Dry Cleaner

Project Summary

An active dry cleaner located in an urban area of Wisconsin was impacted by chlorinated solvents, specifically tetrachloroethene (PCE), trichloroethene (TCE) and breakdown products. The goal was to implement a remedial solution to reduce the concentrations. The State of Wisconsin had special interest in assuring that the remedial action did not stimulate excessive methanogenesis, which could create indoor air/vapor intrusion issues (methane will induce contaminant migration) and cause other potential safety issues associated with high levels of methane.

A thorough analysis of various remedial amendments (EHC®, EHC-L®, EZVI, Ferox-Plus™ and Provect-IR®) were performed, which considered cost, injection capabilities, and predicted performance. Provect-IR® was selected because of its ability to destroy the contaminants while actively controlling methane production.

Remedial Plan

Antimethanogenic in-situ chemical reduction (ISCR) reagent application of 2,700 gallons of Provect-IR® via 24 temporary injection wells.

Results

• Site conditions exhibited favorable ISCR geochemistry with sustained treatment effectiveness.
• Greater than 80% reductions of PCE in groundwater within the source area in 4 months post treatment.
• Approximately 60 to 90% reductions from the surrounding areas.
• Post treatment sampling indicated no excessive methane production.
• No vapor intrusion impacts to surrounding homes and building structures.