Laserfiche WebLink
- Chevron Products Company2 <br />• <br />' Chevron Service Station #9-2033, est Charter Way, Stockton, CA March 5, 2002 <br />On September 9, 1996, Touchstone Developments oversaw the excavation and removal <br />of three USTs, three hydraulic hoists, product dispensers, and associated product lines. <br />Soil samples collected from beneath the former USTs, hydraulic hoists, product piping, <br />and dispenser locations were analyzed for TPHg and BTEX. Hydrocarbon <br />concentrations reported for soil samples collected from beneath the former southern <br />product island (P6) were 3,000 mg/kg TPHg, and 2.6, 20, 47, and 240 mg/kg BTEX <br />components, respectively, at 3.5 feet bgs. On September 11, 1996, soils near the former <br />locations of the USTs, product dispensers, and product lines associated with these test <br />results were removed by excavation. Results for additional samples collected and <br />analyzed following soil excavation suggest remnant hydrocarbon concentrations <br />underlying the former southern product island of 1,700 ppm TPHg and 3.2 ppm benzene <br />at 6 feet bgs, and 1,300 ppm TPHg and 14 ppm benzene at 7 feet bgs west of the <br />southern product island. <br />7 x6(00 CcFT- I°.-0f.x".e <br />Data collected during the previous investigations suggests a complex sequence of <br />interbedded fine-grained and sandy layers comprise the top 95 feet of the soils and <br />unconsolidated sediments beneath the site. Groundwater appears to be present in two to <br />three water -bearing zones underlying the site. The upper water -bearing zone suggests <br />the groundwater flows to the east-northeast under a hydraulic gradient of 0.005 ft/ft. <br />Groundwater in the uppermost water -bearing zone appears confined or semi -confined <br />by overlying fined -grained mixtures. Field observations suggest groundwater rose up to <br />25 -feet above the level encountered in borings. <br />1\Chevron\92033\REP0RTS\9-2033 SA CPP WPFA.doc <br />