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' PREVIOUS SITE ASSESSMENT AND SAMPLING i ' On 23 June 1997, three soil probe borings (BI through B3) were advanced at the site Three additional soil bonngs (B4 through B6) were advanced and completed as ground water monitoring wells on 08 to 11 September 1997, boring B4 (MW-1) was established at the western edge of the ' station parking lot, boring B5 (MW-2) was advanced at the north end of the drive way entrance to the parking lot and boring B6 (MW-3) was advanced at the east edge of the parking lot Analytical ' results of soil samples collected from the soil borings indicated that Hydrocarbon-unpacted soil was present in the vadose zone below the former UST location, within saturated zone in the locations of the newly installed well MW-1,and distributed in the ' capillary zone Soil encountered at 35 feet bsg in the boring established for well MW-1 was not impacted by detectable concentrations of petroleum hydrocarbons, while soil at depths between 43 and 70 feet bsg were impacted by petroleum hydrocarbons ' * The impacted soil encountered between 43 and 70 feet bsg in MW-1 appears to be part of a significant, undefined plume,possible associated with the former dispenser island more than ' 20 feet southeast of the well Impacted soil encountered in the former UST cluster may extend, at depth,to the MW-1 area, ' but the lower hydrocarbon concentrations in the former UST cluster suggest otherwise No soil contamination was encountered in boring B2, which extended only to 35 feet bsg The ground water monitoring network has been monitored nine times since September 1997 Over that time span, the highest concentrations of dissolved hydrocarbons was detected at well MW-1, at the western edge of the site At that tune, the lateral extent of dissolved hydrocarbons is not defined west, south and north of well MW-1 or south and north of well MW-2 I CPT LITHOLOGIC INVESTIGATION On 12 and 13N m November February 2002,three soil boring(CPT-1, CPT-3 and CPT-4)were advanced I on-site and off-site utilizing CPT technology Lithologic data was collected from these three CPT borings Soil borings were then advanced to collect grab groundwater and soil samples from selected depths Soil boring CPT-2 was advanced without a CPT sounding (Figure 2) Ground water sample was collected from the CPT borings at the following intervals o CPT-1 was sampled between 84 feet and 88 feet bsg and between 111 feet and 115 feet bsg, a CPT--2 was sampled between 76 feet and 80 feet bsg and between 111 feet and 115 feet bsg, I o CPT-3 was sampled between 51 feet and 55 feet bsg, between 71 feet and 75 feet bsg, between 96 feet and 100 feet bsg and between 118 feet and 122 feet bsg, and ICPT-4 was sampled between 78 feet and 82 feet bsg and between 121 feet and 125 feet bsg, i Soil samples were collected at 60 and 75 feet bsg in CPT-4 Advanced GeoEnvironmentA Inc