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11 ► �i <br /> HYDROCARBON DISTRIBUTION IN SOIL <br /> Soil samples collected from Boring B-1 at depths of 17 and 31 fbg contained TPPH at <br /> concentrations of 2,100 ppm and 4 5 ppm, respectively Soil samples collected from 12 fbg and 35 <br /> fbg from Boring B-1, and all three soil samples collected from Boring B-2, did not contain detectable <br /> levels of TPPH Benzene was detected at a concentration of 0 57 ppm at 17 fbg in Boring B-1 <br /> Benzene was not detected in any of the other soil samples Fuel oxygenates were not detected in any <br /> of the soil samples The soil chemical analytical data are summarized in Table 2 and presented on <br /> Plate 2 Laboratory analytical data are presented in Appendix C <br /> HYDROCARBON DISTRIBUTION IN WATER <br /> The water sample collected from a localized free water zone encountered in Boring B-1 contained <br /> 110,000 ppb TPPH, and 260 ppb benzene, and did not contain detectable levels of oxygenate <br /> compounds <br /> Water chemical analytical data are summarized in Table 3 and presented on Plate 2 Laboratory <br /> analytical data are presented in Appendix D <br /> . CONCLUSIONS <br /> The vertical extent of TPPH, benzene, and oxygenate compounds have been delineated by Borings <br /> B-1 and B-2 at depths above those at which ground water is encountered TPPH, benzene, and <br /> oxygenate compounds were not detected in Boring B-1 in the soil sample collected at 35 fbg TPPH, <br /> benzene, and oxygenate compounds were not detected in any of the three soil samples from Boring <br /> B-2 Additionally, the lateral extent of petroleum hydrocarbons has been delineated to the east of <br /> the western dispenser island by Boring B-2 <br /> The Iocalized water zone encountered in B-1 between 14 and 17 fbg does not appear to be <br /> representative of true ground water at the site Soil samples collected below this water zone were <br /> found to be moist, not saturated Boring B-2 and previous borings drilled at the site did not encounter <br /> water at this depth, indicating that this water zone is localized and not laterally continuous The <br /> depth to ground water in Wells MW-1, MW-2, and MW-3 was most recently recorded at <br /> approximate depths of 41 to 42 fbg, which is consistent with regional ground water depths <br /> Since TPPH, benzene, and oxygenate compounds were not detected in the soil sample from 35 fbg <br /> from Boring B-1, it appears unlikely that petroleum hydrocarbons detected in the free water zone <br /> have migrated to the depth of ground water <br /> 240-0832 4 <br />