Project Summary

ORIN successfully implemented Free Product Removal (FPR) in-situ chemical oxidation using catalyzed sodium persulfate to treat LNAPL, contaminated soil, and groundwater. Treatment chemistry was injected while the Geoprobe rods were raised throughout the target interval. A vac truck was present to remove LNAPL
and desorbed contaminants while providing hydraulic control.

Approximately 2,400 gallons of 20% sodium persulfate catalyzed with PermeOx Plus was injected into 47 DPT injection locations. A second polish injection was needed to achieve site cleanup goals. In June of 2011, 24 DPT points were injected with approximately 1,200 gallons of 20% catalyzed sodium persulfate treatment.

Project Results

The catalyzed sodium persulfate treatment chemistry removed the free product and reduced the dissolved phase BTEX concentrations at the most contaminated well by an average of 78%, between pre-injection and post-injection sampling. Additionally, subsequent sampling events have observed no measurable LNAPL. The residual PermeOx Plus catalyst will continue to provide an oxygen source promoting bioremediation.