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CURRENT CONDITIONS <br /> Soil <br /> The source of petroleum hydrocarbon impacted soil at the subject site was the 10,000 gallon unleaded <br /> gasoline UST and the 500 gallon leaded gasoline UST. All of the UST's have been removed and the <br /> surrounding impacted soil was removed. Based upon analytical results and the the investigations <br /> conducted at the site, all impacted soil has been removed and consequently does not present a threat to <br /> groundwater quality. <br /> Groundwater <br /> The two most recent quarterly groundwater monitoring and sampling events were conducted in <br /> December 1994 and February 1995. Groundwater samples collected during these events were analyzed <br /> for TPHg and BTEX. These samples did not contain detectable concentrations of TPHg or BTEX. <br /> A well survey and review of groundwater gradients from shallow wells at UST sites in the vicinity <br /> indicate that flow is generally northerly in the site area, toward a convergence in northeast Stockton <br /> near the intersection of Cherokee and Waterloo Roads. This gradient convergence is also consistent <br /> with San Joaquin County Flood Control Maps which show both northerly and easterly components of <br /> groundwater flow in the vicinity of the Nor-Cal site. <br /> A thorough review and investigation of available groundwater flow data in the vicinity of the subject <br /> site has indicated that the hydropunch boring was located downgradient from the former UST pit. The <br /> groundwater sample collected from this location.did not contain detectable concentrations of TPHg or <br /> BTEX. The results of the hydropunch sample, in combination with the absence of TPHg or BTEX <br /> concentrations in MW1 over the last two quarters indicates that groundwater beneath the site is not <br /> impacted with petroleum hydrocarbons. <br /> A more detailed discussion of the groundwater flow characteristics in the site area is contained in the <br /> December 20, 1993 report and the July 2, 1994 letter included in Attachment A. <br /> SUMMARY/RECOMMENDATIONS <br /> Nor-Cal has complied with all PHS/EHD and CVRWQCB requests for additional investigations, <br />_ data collection, well surveys, and confirmation of gradient direction beneath the subject site. <br /> 5 <br />