SITE INFORMATION AND CORRESPONDENCE_FILE 1

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2652 (c)(6) see attached unauthorized release report. All UST's and associated piping were removed on April 10, 1996 and transported under hazardous waste manifest to Richmond, California where each were properly destroyed by Erickson, Incorporated. (7) Corrective action taken to date includes the removal of backfill soil suspected to be hydrocarbon-impacted from the fuel and used oil tankpits. The volume of soil stockpiled from the used oil tankpit was estimated as 80 cubic yards. The volume of soil stockpiled from the fuel tankpit was estimated as 400 cubic yards. Stockpile soil samples were collected on April 10, 1996 by a representative of Touchstone Developments(Robert Mallory) to characterize hydrocarbon concentrations for offsite disposal purposes. Based on field observations, it is expected that overexcavation will be performed to remove remaining hydrocarbon-impacted soil from within the used oil tankpit area. The final decision to perform this work will be based on analytical results of samples collected from the used oil tankpit on April 10, 1995. Any overexcavation performed will be done according to procedures described in Touchstone Developments Corrective Action Plan(1120196). A soil and groundwater investigation was performed at the subject site on July 25 and 26, 1995 by Chevron's consultant,Pacific Environmental Group. Four soil borings were drilled and were converted to groundwater monitoring wells. No petroleum hydrocarbons were detected in any of the soil samples. A detection of 6.0 ppb tetrachloethene was measured at well MW-3 downgradient of the used oil tank location. This detection has not been attributed to the service station operations. A final report documenting all UST removal activities, excavations, soil stockpile characterization,and disposal will be submitted to San Joaquin County Public Health Services within 45 days of completing such activities. Future site investigation will include groundwater monitoring to assess groundwater conditions beneath the site throughout a complete hydrologic cycle. Due to the anticipated destruction of at least one groundwater monitoring well, it is expected that at least one replacement well will be drilled. (8) The method of cleanup implemented to date has been limited to the removal of hydrocarbon- impacted backfill that was associated with the former UST pits and fuel dispenser areas. Further cleanup activities will be determined upon review of pending soil analytical results. Once the need for further cleanup has been determined, limited soil excavation and disposal will be implemented according to Touchstone's corrective action plan. The results of any soil excavation will be included in Touchstone's UST removal report that will be submitted within forty five days upon completion of all associated field work. (9) A total of approximately 480 cubic yards of soil were stockpiled at the subject site.These soils were generated during the removal of all UST's and piping. All stockpiled soil was sampled by Touchstone Developments according to protocol established by BFI Landfill in Livermore, California. Any additional soil stockpiled as a result of overexcavation will be handled similarly. Copies of all soil disposal manifests will be submitted as soon as they are available. (10) All new underground storage tanks and lines are being installed under permit by San Joaquin County Public Health Services. (11) Future releases will be prevented through the installation of underground storage and dispensing equipment that meets or exceeds all applicable regulations. 2652(d) Chevron will comply with all reporting requirements specified within this subsection. (e) Chevron will conduct initial abatement, site characterization,and additional corrective action as specified within this subsection,within sections 2653, 2654,and within Article 11.