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to and down-gradient (CPT2) from the location of the former USTs The results associated with CPTI indicate an increasing trend of contaminant concentration with depth with benzene concentrations ranging from 65 µg/L at 79 to 83 feet bgs, to 1,900 µg/L in the deepest sample collected at 119 to 123 feet bgs As opposed to CPTI, the results associated with CPT2 indicate a trend of decreasing groundwater contaminant concentration with depth, with a benzene concentration of 17,000 gg/L at 74 to 78 feet bgs and 150 gg/L at the refusal depth of 107 feet bgs The results of the deepest groundwater samples collected from the hydropunch borings associated with the CPT borings indicate that the vertical extent of petroleum hydrocarbon contamination has not yet been fully characterized No soil horizon was encountered dut ing the investigation that apparently has substantially impeded the vertical movement of gasoline contamination Laboratory analytical results from hydropunch groundwater samples indicated that shallow groundwater northeast of the site is not impacted by gasoline constituents at or above the laboratory reported detection limits Results of the groundwater samples collected north of the site indicated that the shallow groundwater immediately north of the site has been impacted by moderate and low concentrations of gasoline constituents Results of the groundwater samples collected wells screened below the current water table indicate that the lateral and vertical extent of groundwater contamination has not been fully investigated north of the site The highest concentrations of gasoline constituents were detected in the shallow groundwater sample collected near the former location of the USTs with benzene at 15,000 }tg/L MTBE iso-concentration contours constructed with the shallow groundwater data from the investigation indicated a low concentration MTBE plume The plume is apparently from an off-site source located southwest of the site and not from the former USTs at the site The low concentrations of benzene detected may also be from an off-site source located southwest of the site based on the distribution of the benzene contamination in that area Based on the results of the March 2002 investigation, Condor has recommended additional groundwater investigation at the site to further evaluate the vertical distribution of the containmant plume Condor is currently in the process of preparing a work plan to define the lateral and vertical extent of gasoline contamination at and near the site, the plan will likely include additional CPT bonngs and discrete depth sampling and probably follow-up monitor well installation P 12038 CanLINI Park\Quarterly Monitoring Reports12002]ulyl5rte Background 7-2002 doc