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INFORMATION SHEET ORDER NO. R5-2003-0166 CONTIGROUP COMPANIES FRENCH CAMP GRAIN ELEVATOR ENHANCED BIOREMEDIATION PILOT STUDY SAN JOAQUIN COUNTY ContiGroup Companies formerly owned the active grain storage and transfer facility at 9504 South Harlan Road in French Camp. Historically, liquid fumigants containing carbon tetrachloride were stored on site in five gallon buckets. Carbon tetrachloride polluted groundwater was found in 1999. Several investigations have been conducted to delineate the extent of carbon tetrachloride and its breakdown product, chloroform. Three water bearing zones are identified at the site with most of the mass of pollution in the B water bearing zone. The B water bearing zone is about 60 to 70 feet below ground surface and vanes from about 5 to 10 feet thick across the site. The enhanced bioremediation pilot study proposed is the injection of the proprietary polylactate compound,Hydrogen Releasing Compound (HRC®). The purpose of the pilot study is to evaluate HRC® as a remedial alternative and to determine the necessary spacing and dosage for full-scale HRC®injections. The pollutants at the site are undergoing reductive dechlorination under anaerobic conditions. Under anaerobic conditions, carbon tetrachloride and its breakdown product chloroform are degraded by indigenous microorganisms to carbon dioxide and water. The remedial process depends upon stimulating growth of the indigenous microorganisms by providing a carbon substrate in the form of HRC®. The Discharger proposes to inject four pounds of HRC®per linear foot of vertical depth through nine injection points into the B water bearing zone upgradient from monitoring well MW-313, which is the area with the highest concentrations. The WDRs require extensive monitoring to evaluate the effects of the proposed injection. When the pilot study is completed,the amendments and byproducts shall not exceed baseline levels. DLL 9/24/03