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Remediation of Petroleum Contaminated Soils with OBC™ Case Study

Oxygen BioChem (OBCTM) is a proprietary mixture, manufactured by our partner Redox Tech, of persulfate and calcium peroxide used to promote chemical oxidation and aerobic bioremediation of petroleum contaminated soils and groundwater.

The mixture in OBC supports a two-fold mechanism for destroying the contaminant of concern, delivering one of the strongest chemical oxidants for short-term chemical oxidation (ISCO), as well as delivering electron acceptors (oxygen and sulfate) for longer-term biologically induced oxidation.

OBC was successfully used for the remediation of petroleum contaminated soils to reduce concentrations of benzene, toluene, ethylbenzene, and xylene (BTEX), methyl tert-butyl ether (MTBE), and naphthalene at a rental car facility in the northeastern United States.

As a result of operations, petroleum hydrocarbons were released to the subsurface over the course of many years leaving a plume covering an area of approximately 10,400 square feet. Initially, a pilot test was performed where OBC was injected to address the highest contaminant concentration well in the plume.

Site Map

Approximately 2,880 lbs of OBC in 2,000 gallons were injected through Geoprobe rods at multiple depths (between 11’ and 18’ below ground surface) in four locations around MW 28 on May 25 and May 26, 2010. Concentrations of the target constituents were reduced by more than 94%.

Full-scale injections were performed in June 2012. In this campaign, approximately 25,550 lbs of OBC in approximately 12,180 gallons were injected through Geoprobe rods at multiple depths in 58 locations in approximately 6 days. 

Results

After one year, significant reductions in wells have been observed in the plume monitoring wells.  Although the chemical oxidation phase produced excellent reductions, additional reductions in concentrations are expected as the site progresses through the anaerobic bioremediation phase. 

For more information on Oxygen Biochem (OBCTM) and the remediation of petroleum contaminated soils and groundwater, please download our OBC Technical Brief