Laserfiche WebLink
[IiF-it 1)[R <br /> 1 EXECUTIVE SUMMARY <br /> r-" <br /> The following is Kleinfelder's soil assessment report for the San Joaquin County Motor <br /> Pool facility in Stockton, California. In May 1988, two underground waste oil storage tanks <br /> were excavated and removed from the site. Petroleum hydrocarbon concentrations were <br /> - detected in soil samples collected from the native soil at the bottom of the two excavations. <br /> San Joaquin County Public Health Services, Environmental Health Division requested an <br /> assessment of the lateral and vertical extent of contamination in the vicinity of the <br /> excavations. <br /> In November 1989, Kleinfelder collected and analyzed select soil samples fror.;six borings <br /> drilled in the vicinity of the two excavations. Petroleum hydrocarbons were detected in <br /> only one of the six borings, and the concentrations decreased significantly with depth. <br /> `II <br /> Ground water was encountered at a depth of 56.5 feet below the ground surface; 35 feet <br /> below the deepest petroleum hydrocarbon concentratfin of 12 mg/1-g. h',"C" 44 <br /> Based on the analytical results from Kleinfelder's soil assessment and the previous tank <br /> -� excavation sampling, most of the petroleum .hydrocarbon contamination appears to be <br /> i. limited to the bottom of tank excavations. Kleinfelder does not recommend further <br /> assessment of petroleum hydrocarbon migration in the vicinity of the two excavations. San <br /> r Joaquin County,Department of General Services should seek approval to properly backfi,l <br /> and cap the two excavations. Petroleum hydrocarbon concentrations remaining at the <br /> bottom of the excavations will degrade over time. <br /> t'S <br /> A copy of this report should be submitted to San Joaquin County Public Health Services, <br /> Environmental Health Division for their review and consideration. <br /> 241-89-2196 1 <br />