RPS Group, LLC

Remediation Strategy & Approach

RPS GaiaTech is performing remediation at a Tier 1 Automotive Supplier in Central Michigan with chlorinated solvent and hexavalent chromium impacts in soil and groundwater. Remediation strategy/approach includes source control using in-situ technologies, long term monitoring, engineered barriers and institutional controls. Treatment technologies consist of In-situ Chemical Oxidation (ISCO) using a persulfate/peroxide solution to address solvent impacts and Chemical Reduction using calcium polysulfide solution to treat chromium impacts. Remediation activities are being conducted under the MDEQ Part 201 Voluntary Cleanup Program.

Two series of injections were conducted consisting of 46 injection points in solvent impacted areas and 39 injection points in chromium impacted areas. Approximately 5,300 of oxidant and 2,400 gallons of reductant were injected during the two events. Performance monitoring is being conducted with preliminary results showing stable or decreasing concentration trends.