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Mr Harlan Knoll, REHS 2 July 24, 1992 ' i r i inspection pumped, and rendered inert with dry ice Visual inspect f the tanks 0 o and tank piping showed no holes or apparent signs of leakage. The tanks were transported by Triangle, Inc. to their Sacramento, California facility for disposal. A representative from the San Joaquin County Public Health ' Services Environmental Health Division (Environmental Health) and the Manteca Fire Department were present during removal of the tanks ' 2. The Canonie site engineer collected seven soil samples from the native sandy soils underlying the three tank footprints and one sample 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 as gasoline (TPH-G). The soil samples from the footprint of the 8,000-gallon tank which contained leaded gasoline and beneath the pump Islands were also analyzed for total lead and ethylene dibromide (EDB). The excavation did not reach ground ' water. 3. During tank removal activities, soil excavated from the tank pit and piping trenches which was field identified as contaminated was stockpiled on plastic film at the site. Excavation at the pump islands could not be performed due to the location of the canopy footings The soil stockpile ' contained approximately 150 cubic yards of soil. Six discrete samples were taken from various locations on the stockpile and analyzed for BTEX and TPH-G. After the excavation was completed, the stockpile was ' covered with plastic film The stockpile has been subsequently transported to Callahan Ranch in Red Bluff, California for treatment by aeratio n/b lore mediation. A letter from Time Oil discussing the disposition of the soil stockpile was forwarded to Ms Carol Oz on May 21, 1992 ' 4. The tank pits were backfilled with the soils excavated from the new tank excavation by the contractor. This fill was compacted to minimize settling. ' A summary of the chemical analyses performed is given in Table 1 . As shown in the table, all of the UST excavation soil samples indicated non detectable (ND) or trace ' concentrations for all analytes with the exception of the sample taken from the west end of the former 12,000-gallon tank (035-TP2-W14 5) which indicated the presence of a TPH-G at 460 parts per million (ppm), toluene at 1 .6 ppm, ethylbenzene at 1 .7 ppm, xylenes at 15 ppm, and ND concentrations of benzene. The soil sample taken under the southern most pump island indicated ND concentrations of all analytes. The northern pump island sample (035-PUMP2-4 51) indicated the presence of TPH-G concentration at 13,000 ppm, benzene at 24 ppm, toluene at 400 ppm, ethylbenzene at 160 ppm, xylenes at 1200 ppm, ethylene dibromide at 0.064 ppm and ' PL191-6341REPORTSIKNOLL RPT[July 22, 19921 wwEnvlronmental