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i• �Pu vpp � a m N i ,828 i i6.2.11 Area 1111 i Area BI I (Figure 4c) is centered on BB-138/188,where the 5.5-6 foot soil sample from 7,300 mg/kg TPH-cr, 1,800 mg/kg TPH-d, and no detectable BTEX. No field evidence of hydrocarbons were noted during drilling. Hydrocarbons were also noted at a depth of 10 feet. i This area is laterally,defined to no detectable petroleum hydrocarbons by BB-137,1313-139, 1313- 158, and BB-173. In addition,the vertical extent of hydrocarbon impact in soil is defined to 5.8 mg/kg TPH-d by 20 feet bgs. No hydrocarbon impact was detected in the groundwater in this i area. 6.2.12 Area B12 iArea B12(Figure 4c)is centered on BB-131 where the 5.5-6 foot sample contained 4,200 mg/kg TPH-cr and 1,000 mg)kg TPH-d. No BTEX was detected. Neither hydrocarbon odor nor i hydrocarbon staining was observed in the soil cores from this area. Hydrocarbons showed a sharp drop between the 6 foot sample and the 10 foot sample from 4,200 mg/kg to 210 mg/kg. Hydrocarbons were not detected below the 10 foot depth. This area is laterally defined to 1.0 img/kg TPH or to no detectable hydrocarbons by 1313-130, BB-132, BB-159, and 1313-174. . Groundwater in BB-189 contained 820 µg/L TPH-cr and 600 µg/l,TPH-d. No BTEX constituents were detected in the groundwater. i7.0 PIPELINE EXTRACTION Pipeline extraction activities were carried out between July 11, 2005 and July 27, 2005. Excavation to expose the former pipelines occurred between July 11 and July 15, 2005. During the excavation, visibly impacted soils were detected in the vicinity of areas B-3 (near boring BB- 4, BB-5,1313-107, and BB-108) area B-6 (near boring BB-40, BB-46, and BB-50). The areas noted to be impacted during the pipeline removal are coincident with areas identified during the subsurface investigation. On July 18 and July 19,2005, the pipelines were pigged and cleaned. The pipelines were removed following being cut into approximately 40 foot sections on July 25 and July 26, 2005, and the trench was backfilled on July 26 and July 27, 2005. I8.0 DISCUSSION i A total of 12 areas were identified with impact to soil and/or groundwater. Of these, three showed impact in soil extending to groundwater. A total of eight areas exhibited impact to groundwater. Four areas exhibited impact to groundwater in the grab groundwater samples I abovel,000 ug/L. Eight of the areas.either exhibited no groundwater impact or impact below 1,000 ug/L. In most of the borings where hydrocarbon impact was observed, TPH-cr and TPH-d Iconcentrations attenuated between 10 and 15 feet bgs (e.g. BEA, BB-5, and BB-46). Only four 8 Ip�tl5\I'110113Cf$LWJW)]f9Shell M..,,r.i.H...'Vd,hb.c,&N6,hb BWcighB 0.epon'B summoryrepondoc