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LEVINE-FRICKE slurry was injected into this area to provide structural integrity between the compacted backfill material and overlying loading dock. The piping trench backfill was compacted using Whacker equipment. 3.0 CHEMICAL ANALYSES AND RESULTS Soil samples were analyzed for total petroleum hydrocarbons (TPH), using EPA Method 8015 to detect diesel and gasoline, and for purgeable aromatics (benzene, toluene, xylenes and a- ethylbenzene [BTXE]) using EPA Method 8020. Samples were also analyzed for ethylene dibromide (EDB) using EPA Method 8240, and organic lead, using DHS methodology, as requested by the SJLHD, since the tank at one time had apparently stored leaded gasoline (as noted on the former dispenser). Chemical analysis results are summarized in the table on Figure 2, and copies of laboratory certificates are included in Appendix B. Analysis results indicate that TPH as diesel and gasoline were not detected above laboratory detection limits (10 ppm) in any of �. the soil samples, with the exception of sample DI -2.51, collected beneath the former dispenser. Gasoline was reported at a concentration of 390 ppm, and diesel at a concentration of 37 ppm in this sample. Benzene, toluene, xylenes and ethylbenzene were not detected above laboratory detection limits (0.025 ppm for benzene and toluene, and 0.075 ppm for xylene and ethylbenzene) in any of the soil samples, with the exception of 0.065 ppm of toluene reported in sample PP4-31. This concentration of toluene is considered to be low in relation to the RWQCB guidelines for allowable toluene concentrations in soils (0.3 ppm with high leaching potential conditions, as referenced in the December 1987 Leaking Underground Fuel Tank Field Manual). Organic lead was not detected in any of the analyzed soil samples. EDB was detected in three samples (TS -141, PPl-3' and PP4-31) at concentrations ranging from 0.180 to 0.370 ppm, and was not detected above a detection limit of 0.125 ppm in the other samples. 3.1 Discussion of Results The presence of 390 ppm of gasoline detected in the soil sample collected from below the dispenser island indicated that limited fuel leakage has occurred in this area. Field observations suggest that this leakage has occurred over a very small area, however, and does not appear to represent a significant release. -4-