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� CAMB R IA Results- The closest receptor to the subject site is a domestic well located approximately 450 feet northeast of the site, and a second domestic well is located 850 feet east of the site Since the predominant groundwater flow direction at the subject site ranges from northeast to southeast, these two domestic wells (labeled 1 and 2 on Table 5 and Figure 1) are located downgradient of the subject site Cambria has not confirmed that these wells still exist or are currently used Cambria recommends further research and field reconnaissance to determine the current status of these two wells The municipal well and the third domestic well are located upgradient to crossgradient of the subject site at distances of 2,000 feet, therefore, it is highly unlikely that any site activities would impact these receptors No surface water bodies were identified within the survey area CONCLUSIONS Soil borings SB-5 and SB-6 were drilled near the former USTs and near the northern dispensers, respectively, to delineate the vertical extent of petroleum hydrocarbons and MTBE the soil beneath the site No TPHg was detected at or below 60 5 fbg and no benzene was detected at or below 80 5 fbg in SB-5, delineating these constituents in soil in the former UST area MTBE was not detected at any depth in soil from SB-5 Boring SB-6 was drilled adjacent to the northern dispensers Data from boring SB-6 delineates benzene in soil at 70 5 fbg and data from previous work in the vicinity of SB-6 delineated TPHg in soil at 66 5 fbg and delineated MTBE at 615 fbg The vertical extent of TPHg and benzene in soil near the southern dispensers has previously been delineated at 26 5 fbg and delineated MTBE in soil at 36 5 fbg Soil and well borings drilled during previous investigations delineate the lateral extent of TPHg and benzene in unsaturated soil onsite Detections of these compounds at depths of approximately 50 fbg and deeper are likely caused by impacted groundwater beneath the site Data from these borings also delineate the lateral extent of MTBE in unsaturated soil north of the dispensers and west, south, and southeast of the site Groundwater samples from borings SB-5 and SB-6 contained TPHg and benzene to depths of 97 fbg MTBE was not detected in boring SB-5 MTBE and DIPE were not detected at or below 60 fbg in boring SB-6, delineating them vertically in groundwater near the northern dispensers Groundwater results from the fourth quarter 2001 sampling event indicate that the lateral extent of impacted groundwater is delineated to the north, northeast, and west (typically upgradient directions) by wells MW-1, MW-2, and MW-5, with the exception_ of 052-ppb-benzene _ (detection limit 0 50 ppb) in well MW-2 The laboratory noted that TPHg results this quarter in 0854 8