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Site Characterization and Soil remediation Plan: 7500 West Eleventh Street; Tracy, CA. Page 8 is five samples recovered from that pipe trench, but none was present in the three other samples ANALYSIS OF EXCAVATED AND STOCKPILED SOIL The material that was excavated from Tank Pit No. I and Tank Pit No. 2 to effect removal of the underground storage tanks located in those areas was i initially stored in a temporary stockpile (Stockpile No. 1). The hydrocarbon-affected soil removed from the Dispenser Pit was placed in a second stockpile that was then covered with plastic sheeting. The location of that stockpile (designated Stockpile No. 2) is shown on Figure 10. Temporary Stockpile No. I i Following removal of the four registered tanks from Tank Pit No. 1, gravel with particle sizes in the range 3-in. to 1,5-in with very little fines was placed in the bottom of the pit until its surface was just above the water table. It was then compacted by vibration so that the bottom of the pit was stable and dry, To secure the site, overburden material and sand and other material that had "c'`'✓1� covered the tanks in Tank Pit Nos 1 and 2 were removed from temporary Stockpile No-_1 and used as backfill in those pats. Available material from the excavations of those tank--pits was also used to backfill the Dis eraser Pit, but a _ ... ... P. h sheet of industrial plastic was laid over the bottom of that open pit before the backtjI1 material was placed. } At the request of the SJCPHS, six samples from various depths between 4 and' _6 ft. were recovered from the materials used to backfill the Dispenser Pit at the locations shown on Figure 8- Each sample was analyzed for TPHd, TPHg, the BTEX compounds, fuel oxygenates and total lead. The results are presented in Table 3. All six samples contained diesel at various concentrations between 69 mg/Kg and 4,100 mglKg. Gasoline was detected in only two of the samples at 2.2 mg/Kg and 760 mg/Kg- All samples contained extremely low concentrations of one or more of the BTEX compounds. MTBE was detected in four of the six samples, but this analyte was also at extremely low concentrations. The concentration of lead in the samples varied from Not Detectable to 11 mg/Kg, which is well below the concentration naturally present in soil. t J Stockpile No. 2 Initially, two samples — SP2-1 and SP2-2 — were recovered from within Stockpile No. 2, which contains' material that was excavated from the Dispenser Pit- Those samples were analyzed for TPH(d), TPH(g), the BTEX sic