SITE INFORMATION AND CORRESPONDENCE_2001-2005

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INFORMATION SHEET 2 WASTE DISCHARGE REQUIRMENTS ORDER NO. R5-2003-XXXX i LINCOLN CENTER ENVIRNMETNAL REMEDIATION TRUST IN SITU GROUNDWATER REMEDIATION PILOT STUDY,SAN JOAQUIN COUNTY The Discharger proposes to install two injection points to be drilled using hollow-stem auger techniques to a target depth of approximately 50 feet below ground surface (bgs). One injection point will be installed 30 feet in the upgradient direction from existing monitoring well MW-006A and the second injection point will be installed 60 feet in the upgradient direction from existing monitoring well MW-006A. Using these injection wells, compressed nitrogen, at approximately 100 to 200 psi, will be injected into the low permeability sediments at 3-foot intervals between 30 and 50 feet bgs. A dense, fracture network is expected to be created around the injection points. Once fractures have been propagated, GZVI particles (dry or suspended in a water slurry) will be injected through the injection nozzle. Compressed nitrogen will be used to carry GZVI slurry into the subsurface. After injection is completed, the injection points will be abandoned by pressure grouting. The Discharger proposes to install five monitoring well clusters for the proposed pilot test. The locations of the monitoring well clusters will provide characterization of the area of influence of the injection points and assess changes in the contaminant concentrations in groundwater. One well cluster is to be installed upgradient from the treatment zone, three well clusters are to be installed within the treatment zone (between and cross-gradient to the injection points) and one well cluster will be installed downgradient from the treatment zone. Each monitoring well cluster is to include one well screened between 30 and 40 feet bgs and one well screened between 40 and 50 feet bgs. Groundwater will be monitored for changes in water levels and pressure response during the injection procedure. Oxygen and carbon dioxide levels in the wellhead spaces will also be monitored during the injection procedure. Prior to the test, and at 2, 6 and 10 weeks after the test, groundwater will be sampled and analyzed for volatile organic chemicals including PCE, certain cations and anions including iron, the dissolved gas concentrations of ethane and ethene, and general chemistry parameters including pH, total dissolved solids, alkalinity and chloride. The oxidation/reduction potential (ORP) will be measured in the field along with dissolved oxygen (DO). The Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Fourth Edition (Basin Plan), designates beneficial uses, establishes water quality objectives, and contains implementation plans and policies for all waters of the Basin. The beneficial uses the groundwater at the site are municipal and domestic supply, industrial service supply, industrial process supply, and agricultural supply. The arttidegradation directives of Section 13000 of the California Water Code require that waters of the State that are better in quality than established water quality objectives be maintained "consistent with the maximum benefit to the people of the State." Policies and procedures for complying with this directive are set forth in the Basin Plan (including by reference State Water Board Resolution No. 68-16, "Statement of Policy With Respect to Maintaining High Quality Waters in California," or"Antidegradation"Policy).