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.� GEGEC7 locations are shown on Figure 3. Historical soil and groundwater analytical results are pre- sented in Tables I and 2, respectively. 2.2.1 Soil Conditions Petroleum hydrocarbon-affected soil has been identified in two areas along the northern perimeter of the site; (1) within the eastern area of the site adjacent to the existing building and (2) further west in an area currently used for automobile parking(Figure 3). The lateral extent of petroleum hydrocarbon(i.e., crude) affected soil has been delineated within the eastern area of the site adjacent to the existing building with borings GMX-2, GMX-7, GMX-6, MW-3, and GM-5. As shown on Figure 3, petroleum-affected soil in the western portion of the site is laterally defined to the northwest,northeast, and southeast by borings GMX-4, WSFMW-1, and GM-2, respectively. Historical sampling results indicated that TCE is present in shallow soil within a limited area directly adjacent to the building, in the area of GMX-1. Multiple soil borings have been com- pleted at the site since 1995 to investigate the extent and magnitude of TCE-impacted soil (ERM-West Inc., [ERM] 1995a, 1995b, Geologic Technics Inc., [GTI] 1996, and WHF Inc., [WHF] 1996b). The highest concentration of TCE measured at the site was 9.5 milligrams per kilogram (mg/kg) in a soil sample collected from boring S-6 in 1995 (ERM, 1995a). The lat- eral extent of TCE in soil has been defined. TCE has not been detected in soil samples col- lected at depths greater than 10 feet bgs at the site with the exception of one sample collected at 14 feet bgs from a trench that contained 0.32 mg/kg of TCE (WHF, 1996). 2.2.2 Groundwater Conditions Based on historical and current water level measurements,groundwater is encountered between approximately 30 and 35 feet bgs and the horizontal flow direction is to the northeast. Historical groundwater sampling activities include initial sampling ofMW-1 in 1996 by Geological Technics Inc. (GTI, 1996) and MW-2,MW-3, and MW-4 in 1998 by Radian International LLC (Radian), (Geomatrix, 2000). Groundwater sampling activities also in- eluded the collection of grab groundwater samples from locations downgradient and in the vicinity of well MW-1. Grab groundwater samples were collected from three CPT borings (CPT-1, CPT-2, and CPT-3) advanced adjacent to MW-1 by Radian in 1997 and from one direct-push boring (GMX-6) advanced off-site by Geomatrix in 1999 (Geomatrix, 2000). ® t Groundwater results of samples collected by Radian International LLC were reported in Geomatrix's February 2001 Soil and Groundwater Investigation Report. 1l4)akI%deptdata\Doc_Safe16000s16447.0011ReponlUS Can SodGW Rpt.doc 3