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Former Discovery Chevrolet August 12, 1994 PREVIOUS WORK Based on information supplied by Ms. Nokes, we understand thatt/the three USTs and associated product piping and dispensers were removed in April, 1993. Four soil samples were collected from the base of the gasoline UST excavation at depths of approximately 9 to 10 feet below ground surface (bgs), one soil sample was collected from beneath the product dispenser at approximately 5.5 feet bgs, and one soil sample was collected from the base of the waste oil UST excavation at approximately 7.5 feet bgs. Groundwater was not encountered during UST removal. Petroleum hydrocarbons were detected in all soil samples. Soil samples collected from the gasoline UST excavation contained TPH-Gasoline concentrations ranging from 920 to 4,400 part per million (ppm). Benzene was detected in all these samples at concentration ranging from 5.9 to 39 ppm. Total lead was detected in two samples at concentrations of 19 and 4.0 ppm. TPH-Gasoline was detected in the soil sample collected beneath the product dispenser at a concentration of 21 ppm. Benzene was detected in this sample at a concentration of 0.88 ppm. TPH-Gasoline, Total Petroleum Hydrocarbons as Diesel (TPH Diesel), and benzene were detected in the sample from the waste oil excavation at concentrations of 31 , 270 and 0.18 ppm, respectively. Lead and chromium were detected in these samples at concentrations 7.8 and 9.2 ppm, which are above their respective STLCs of 5.0 ppm. These tank removal data have previously been submitted to SJCEHD. PROPOSED SCOPE OF WORK To assess the lateral extent of hydrocarbonimpacttosoils_b_eneath the-site and assess whether groundwater beneath the to has been impacted, proposes to install three groundwater monitoring wells onsite at the locations shown on Figure 2. Groundwater is reported to be approximately 10 feet bgs, and is assumed to flow to the northeast. One monitoring well will be installed approximately 10 feet north of the former gasoline UST excavation to assess possible downgradient impact to groundwater and investigate hydrocarbon impact to soils north of the excavation. The second well will be as far south of the former gasoline UST excavation as possible given site conditions. The third well will be installed within ten feet northeast of the waste oil UST excavation to assess possible groundwater impact downgradient of the area. Report No. 6146.701-1 2 GeoStrategies Inc.