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Mr Harlan Knoll 2 July 24, 1992 inert with dry ice. Visual inspection of the tanks and tank piping showed no holes or apparent signs of leakage. A representative from the San Joaquin County Public Health Services Environmental Health Division (Environmental Health) and the Stockton Fire Department were present during removal of the tanks. The tanks were transported by Erickson, Inc. to their Richmond, California facility for recycling. 2 The Canonie site engineer collected seven soil samples from the native sandy soils underlying the three tank footprints and one sample from under each pump Island. Pipe trench samples were not required due to the short distance between the limits of tank excavation and the pump islands. All soil samples were analyzed for benzene, toluene, ethylbenzene, xylenes (BTEX) and total petroleum hydrocarbons quantified as gasoline (TPH-G). The soil samples from the footprint of the 8,000-gallon tank which contained leaded gasoline, the 12,000-gallon tank which had historically contained leaded gasoline, and the two pump islands were also analyzed for total lead and ethylene dibromide (EDB). Ground water was not encountered In the excavation. 3 Soils excavated from the tank pit was temporarily stockpiled on plastic film at the site. The pile contained approximately 150 cubic yards of soil. Six discrete samples were taken from various locations on the stockpile. The samples were analyzed for BTEX, TPH-G, and total lead. 4 The tank pits were backfilled with the stockpiled soils and the soils extracted from the new tank excavations by the contractor. The soil excavated from the tank pit was reused as backfill due to the high amount of contamination in the remaining native soil and the lack of ground water at the site Time Oil decided, with Environmental Health's knowledge,that the remediation of this soil could effectively be done in conjunction with the remediation of the tank bed A summary of the chemical analyses performed is given in Table 1 As shown in the table, with the exception of the center and southwest sample collected beneath the 12,000-gallon tank, the UST excavation soil samples contained elevated concentra- tions of petroleum hydrocarbons TPH-G concentrations ranged from nondetectable (ND) to 8,900 parts per million (ppm), benzene from ND to 8 9 ppm, toluene from ND to 270 ppm, ethylbenzene from ND to 100 ppm, xylenes from ND to 730 ppm, and EDB from ND to 0 007 ppm. All total lead concentrations were ND. The pump island samples indicated trace toluene concentrations and ND concentrations for all other analytes Stockpile concentrations of TPH-G ranged from ND to 2,700 ppm, benzene from ND to 0 98 ppm, toluene from ND to 22 ppm, ethylbenzene from ND to 24 ppm, and xylenes from ND to 230 ppm 1 PLI91-634MPORTSILOCKEFOR RPT IJuty 22, 19921 CanoWeEnvironmental