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Underground Storage Tank and Product Piping Removal Report -Former Tosco (Unocal) Service Station#5421 June 2, 1998 collected at depths of 22 and 25 feet bgs, respectively Each soil sample was analyzed for TPHg, BTEX, and MtBE and oxygenate compounds These samples contained 16 and 15 ppm TPHg, 0 32 and 0 41 ppm benzene, respectively MtBE or other oxygenates were not detected in either sample On April 21, 1998, the northern center of the pit was overexcavated and samples UX-7-26 and UX-8-26 were collected from the bottom at a depth of 26 feet bgs The samples contained 10 and 24 ppm TPHg, and 0 068 and 0 77 ppm benzene, respectively MtBE or other oxygenates were not detected in either sample In total, an area approximately 26 feet by 20 feet was overexcavated 8 to 12 feet below the base of the original UST pit (25 to 28 teet bgs) Approximately 250 cubic yards of soil were removed during overexcavation activities Former Waste Oil UST Sampling Upon removal of the waste oil UST on April 15, 1998, one soil sample was collected from beneath the center of the UST at a depth of approximately 11 feet bgs The soil sample was analyzed for TPHg, BTEX, MtBE, oxygenate compounds, Total Petroleum Hydrocarbons calculated as diesel (TPHd), Oil and Grease (O&G), volatile organic compounds (VOCs), semi-volatile compounds (SVOCs), and five metals Petroleum hydrocarbons were not detected in the sample Dis enser/Product Piping Sampling Four soil samples were collected in native material immediately beneath the four dispenser locations at a depth of 4 to 6 feet bgs Each soil sample was analyzed for TPHg, BTEX, and MtBE and oxygenate compounds Petroleum hydrocarbon concentrations ranged from not detected to 1 9 ppm TPHg, not detected to 0 82 ppm benzene and not detected to 0 089 ppm MtBE All samples were reported as not detected for oxygenate compounds Hydraulic Lift and Sand/Water Sainplin� Two soil samples were collected in native material immediately beneath the former hydraulic lifts at a depth of 8 feet bgs on April 21, 1998 Each soil sample was analyzed for Total Petroleum hydrocarbons calculated as hydraulic fluid (TPHh) Petroleum hydrocarbons were not detected in either sample One soil sample was collected in native material immediately beneath the former sand/water separator at a depth of 4 feet bgs The soil sample was analyzed for TPHg, BTEX, MtBE, oxygenate compounds, TPHd, O&G, VOC), SVOCs, and five metals The sample was reported as not detected for petroleum hydrocarbons except for 0 016 ppm toluene and 0 023 ppm xylenes SOIL DISPOSAL Soil removed from the gasoline UST pit, waste oil UST pit, product piping trenches, hydraulic lift pits and sand/water separator pit were stockpiled at the site pending disposal profiling and approval from the SJCPHS A total of 784 69 tons of stockpiled soil was transported from the site by Den Beste Transportation, Inc of Windsor, California to the Forward Inc Landfill in Stockton, California for disposal on May 19, 1998 Stockpile chemical analytical data are summarized in • 140162 02 3