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Subsurface Conditions Five exploratory borings were drilled at the locations shown on Figures 1, 2 and 3 the deepest of which was advanced to a termination depth of 26.5 feet. Borings B-1 and B-2 revealed artificial backfill in the former tank pits (see attached Exploratory Boring Logs). Minor gray stain and a weak petroleum odor was observed in the tank pit backfill. These tank pit backfill excavations occurred in a gravelly to sandy clay and silty clay which extends from the surface to depths of 8-to 12-feet. These upper strata are underlain by interbeded clayey silt and sandy clay to depths of 14-to 16-feet. Silty sand to sand underlie the clayey silt and sandy clay to depths of 21- to 26-feet; these sandy strata between approximately 14- to 26-feet form the uppermost waterbearing aquifer strata. A clayey silt, of unknown thickness and lateral extent, underlies the sandy strata and appears to form the underlying confining strata. Moderate to severe flowing of sandy strata occurred during drilling of Barings B-1,B-2 and B-4. Groundwater occurred at depths of about 12 feet and rose in the uncased boreholes to depths of 8.69 to 9.51 feet, suggesting the aquifer strata may be weakly confined. On the basis of field groundwater measurements, groundwater appears to flow to the north; however there was insufficient time for water levels to equilibrate for adequate data to plot a groundwater contour flow direction(see Figure 2). Regional lithologic lateral and vertical variation are present in the shallow aquifer strata and underlying confining strata, which are typical for river and floodplain deposits in this portion of the San Joaquin Valley (see Geologic Cross Section, Figure 3). While lateral and vertical variation are present in the aquifer strata, these strata as a whole form the uppermost waterbearing aquifer (or hydro-) stratigraphy between about 12- to 24 feet in the area explored These underlying confining strata display some lateral lithologic variation, and were not observed to yield water. Nearby Department of Water Resources Drillers (DWR) Log Nos. 145680 (and 219475 for the Water Well) indicate deeper clayey strata underlying the uppermost aquifer. Chemical Analysis Seven soil samples, including two underlying confining strata (boring termination) samples, and five groundwater samples were analyzed at a Chromalab, Inc. State certified analytical laboratory from the exploratory borings. These samples were tested for the following; Total Petroleum Hydrocarbons as Gasoline (TPHG) and Diesel (TPHD), Benzene (B), Toluene (T), Ethylbenzene (E) and Xylene (X), Methyl-tert-butyl-ether (MTBE) and fuel oxygenates, 1,2 Dichloroethane and Ethylene Dibromide using EPA Methods 3510/8015, 8020, 8240 and 8260. The analyses were run on an"normal'turnaround(five- to ten working days). The results are tabulated and presented in Tables 1 and 2 below. Discussion The preliminary site assessment investigation data revealed that highly degraded contaminants were present in the capillary fringe soil, with the dissolved highest groundwater concentrations in the former tank pits (see Figures 1, 2 and 3). Soil samples from Boring B-1 in and near the former tank pit showed low TPHD and TPHG `vft�-