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�Pu vp� n m N I X828 li 6.2.8 Area B8 Area B8 (Figure 4b) is centered on BB-56 and BB-57,where TPH-cr concentrations in soil were detected at 25,000 mg/kg and TPH-d at 11,000 mg/kg at 5.5-6 feet bgs. These borings contained no detectable benzene. TPH concentrations attenuated sharply between these shallow samples and a depth of around 15 feet, to essentially non-detectable levels, consistent with field evidence (hydrocarbon odor and staining), which were observed to a depth of 14.5 feet bgs. Borings BB- 55,BB-58/BB-62, BB-59,BB-60, and BB-61 define Area B8 to a maximum TPH of 61 mg/kg. Groundwater samples were collected both along the pipeline alignment and approximately 25 feet off the alignment in the inferred up- and down-gradient direction. Low to non-detectable concentrations of TPH-cr were noted in groundwater, and similarly, low to nondetectable concentrations of TPH-d were noted(maximum of 310 ug/L). Groundwater from borings BB- 56,BB-59, and BB-61 also contained only a maximum of 0.35 µell,benzene,approximately 1 ug/L. Based on these low concentrations, groundwater in this area is considered delineated. 6.2.9 Area B9 IArea B9 (Figure 4c) consists of three small areas located in close proximity, in the area of borings BB-71;BB-118/BB-184, and BB-125. Boring BB-71 contained low concentrations (190 mg/kg TPH-cr and 77 mg/kg TPH-d) at a depth of 6 feet, and no detectable hydrocarbons at a depth of 11 feet. Boring BB-118/184 contained TPH at concentrations up to 32,000 mg/kg, and which extend to groundwater. Boring BB-125 contained 4,400 mg/kg TPH-cr,but as in boring BB-71,no hydrocarbons were detected at a depth of 10 feet. Groundwater from boring BB-184, located on the alignment, contained up to 21,000 µg/L TPH- cr and 15,000 µg/L TPH-d. TPH was not detected in boring BB-194, located 25 feet downgradient of the alignment;and only TPH-d at a concentration of 290 ug/L was detected upgradient of this location. Similarly, only TPH-d at a concentration of 240 ug/L was detected in boring B13183, in the area of boring BB-71, and no hydrocarbons were detected in boring BB- 186, in the area of boring BB-125. 6.2.10 Area B10 Area B10 (Figure 4c)is centered on BB-123, where TPH-cr was noted in the 6 foot sample at a concentration of 3,100 mg/kg and TPH-d was detected at 670 mg/kg; BTEX compounds were not detected. No field evidence of hydrocarbon were evident during drilling. Hydrocarbons were not detected or detected at low concentrations (3.4 mg/kg TPH-d) at depths greater than 6 feet. This area is laterally defined by BB-122, BB-124, BB-157, and BB-172. No petroleum hydrocarbon were detected in any of these borings. Groundwater in this area contained no TPH V or benzene, and only 0.56 µg/L toluene. 1 p ` N 7 9%k3 pR0)HCTSUW3%0lyl9 Shell M..Wwn H.0 ce eigh b.e.&Ntighb Mcigh B Report%B summary repon.doc