Project Highlights

  • 92% reduction within two weeks
  • 99.9% reduction in two months
  • Combined remedy approach reduced mixed VOC plume to non-detect within nine months (<5μg/L)
  • No rebound in over 18 months of site monitoring

Project Summary

An evaluation of PlumeStop performance was conducted on a section of a mixed chlorinated solvent plume (cVOC) comprising trichloroethene (TCE – 1,390 μg/L) and 1,1,1-trichlorotethane (TCA, 3,550 μg/L) at a former electronics facility in Indiana. PlumeStop was applied in conjunction with the controlled-release electron donor, Hydrogen Release Compound (HRC®). Post-treatment solvent concentrations in groundwater were reduced in two weeks by 92% at the first sampling round. Concentrations were reduced by 99% by the second sampling round (one month) and 99.9% by the third sampling round (two months). No cVOCs were detected above analytical thresholds (<5μg/L) after three months. Source area treatment activities are being monitored for closure and the results are being evaluated as a potential larger scale plume treatment option.

Remediation Approach

PlumeStop was applied perpendicularly to the groundwater flow using 10 direct-push injections around a central monitoring point. Approximately 180 pounds of HRC was applied into three injection points.

REGENESIS Solution Applied

PlumeStop is an innovative in situ remediation technology designed to rapidly reduce contaminant concentrations, stop migrating plumes, eliminate contaminant rebound, achieve stringent clean-up standards and treat back-diffusing contaminants. PlumeStop provides a unique colloidal biomatrix platform which rapidly sorbs contaminants out of the dissolved-phase. Once contaminants are concentrated within the PlumeStop biomatrix, they can be completely biodegraded in place using compatible REGENESIS bioremediation products.

HRC is a controlled release, electron donor material, that when hydrated, is specifically designed to produce a controlled release of soluble lactate. The newly available lactic acid is highly efficient for the production of dissolved hydrogen to fuel anaerobic biodegradation processes in soil and groundwater.

Results

Using a combined remedy approach, the application of PlumeStop and HRC successfully reduced contaminant levels to non-detect and positioned PlumeStop as a viable solution for larger scale projects.