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each boring for a total of six samples. The hand auger was cleaned with water and a non - <br />phosphate detergent between each of the borings. Upon completion of drilling, the <br />borings were backfilled with bentonite chips which were hydrated with clean water, and <br />the asphalt pavement patched to surface grade. <br />Soil beneath the site consisted primarily of well sorted very fine- to medium - <br />grained sand (SW) and poorly sorted medium- to coarse-grained sand (SP) with lesser <br />intervals of silty very fine- to fine-grained sand (ML). Similar soil profiles were <br />encountered in borings B-1 and B-2 which is presented in Type Boring Log A, and in <br />borings B-3 through B-6 which is presented in Type Boring Log B. Boring logs are <br />presented in Attachment A. All of the samples collected for laboratory analysis consisted <br />of poorly sorted unconsolidated sand that is very porous and permeable. None of these <br />samples indicated the presence of petroleum hydrocarbons based on field observations <br />with the exception of boring B-1 which had a faint gasoline odor. <br />Soil samples were capped with teflon tape and plastic end caps, and sealed to the <br />brass liner with duct tape. Samples were maintained in a cooler chest with frozen gel <br />packs ("blue ice"), and maintained at a minimum of four degrees Celsius until delivered <br />to the laboratory. <br />Laboratory Analvsis: <br />Soil samples were analyzed for gasoline -range total petroleum hydrocarbons <br />(TPH), benzene, toluene, ethylbenzene, and xylenes (BTEX), and methyl tertiary butyl <br />ether (MTBE). Analysis was performed using EPA method 8015M for TPH and EPA <br />method 8020 for BTEX and MTBE. Samples were analyzed by a laboratory certified by <br />the State of California for those methodologies. <br />Laboratory analytical results indicate that none of the samples contained gasoline <br />constituents with the exception of boring B-1 which contained trace concentrations of <br />toluene, xylenes, and MTBE. Laboratory analytical results are summarized in Table 1 <br />below. Certified analytical results are presented in Attachment B. <br />Table 1 <br />Laboratory Analytical Results, Super Stop Market, Manteca <br />Sample <br />TPH <br />Benzene <br />Toluene <br />Ethylbenzene <br />Xylenes <br />MTBE <br />B-1 @ 17' <br />ND <br />ND <br />.0078 <br />ND <br />.029 <br />1.5 <br />B-2 @ 17' <br />ND <br />ND <br />ND <br />ND <br />ND <br />ND <br />B-3 @ 17' <br />ND <br />ND <br />ND <br />ND <br />ND <br />ND <br />B-4 @ 17' <br />ND <br />ND <br />ND <br />ND <br />ND <br />ND <br />B-5 @ 17' <br />ND <br />ND <br />ND <br />ND <br />ND <br />ND <br />B-6 @ 17' <br />ND <br />ND <br />ND <br />ND <br />ND <br />ND <br />ND = below detectable concentrations <br />