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Gregg collected soil samples at 65, 70 and 74 feet bgs All three soil samples contained relatively low concentrations of at least one compound analyzed The sample collected at 65 feet contained 10 mg/kg of TPH-as-gasoline, 0 15 mg/kg of benzene, 0 14 mg/kg of toluene, 0 26 mg/kg of ethylbenzene, and 0 73 mg/kg of xylenes The sample collected at 70 feet only contained 0 0071 mg/kg of toluene, and the sample collected from 74 feet only contained 0 02 mg/kg of toluene, 0 0068 mg/kg of ethylbenzene and 0 05 mg/kg of xylenes The five oxygenate compounds, 1,2-dichloroethane (1,2-DCA) and EDB were not detected in any of the three sod sample analyses Based on the CPT and pore pressure dissipation data, groundwater-bearing sand and gravel sequences were identified beneath the groundwater table at approximately 60 and 105 feet bgs Gregg discretely sampled the groundwater interval at 60 feet bgs using a SimulProbe The ' groundwater sample collected at 60 feet bgs contained 5,700 p.g/l of TPH-as-gasoline, 76 pg/l of benzene, 61 µg/l of toluene, 53 µgll of ethylbenzene, 280 pg/l of xylenes, and 11 µg/I of 1,2-DCA ' The five oxygenate compounds and EDB were not detected in the groundwater sample On February 20 and 21, 2002, Gregg advanced two additional CPT borings to further define the stratigraphy of groundwater-bearing soils beneath the water table and evaluate the vertical extent of impacted groundwater One of the borings (CPT-1A) was drilled on-site next to CPT-1 for discrete groundwater sampling only The other boring (CPT-2) was located approximately 150 feet southeast (downgradient) of the site These CPT boring locations are shown on Figure 3 The results from these two CPT borings are documented in Ramage Environmental's Report, Quarterly Groundwater Monitoring and Cone Penetration Testing, dated April 8, 2002 Sandy intervals were observed in CPT-1 at approximately 29 to 35 feet, 57 to 62 feet, and 105 to 121 feet bgs, and in CPT-2 at approximately 28 to 32 feet, 54 to 57 feet, 113 to 119 feet, and 128 to 136 feet bgs Sandy soil intervals beneath the water table appeared to be relatively continuous between the two CPT locations ' Gasoline compounds were detected in the discrete groundwater samples collected at approximately 60 feet bgs at CPT-1A and CPT-2, 105 feet bgs at CPT-1A, and 115 feet bgs at CPT-2 The sample collected at 130 feet bgs at CPT-2 did not contain gasoline compounds - ' Methyl tertiary butyl ether (MTBE) was not detected in any of the discrete groundwater samples As a result, the lateral and vertical extent of impacted groundwater remained undefined 5