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® Groundwater samples were analyzed for TPHg (C6 to C12 carbon range) and TPHd (C10 to C24 ■*f carbon range) using EPA Method 8015 Modified;BTEX using EPA Method 8260B,6 and PAHs using EPA Method 8270 SIM. TPHd analyses were performed both with and without a silica gel preparation procedure. 5.0 RESULTS The following sections describe the results from this investigation. The analytical results for ® soiI samples are summarized in Table 3. Groundwater analytical results from the monitoring wells are summarized in Table 2, along with the historical results from these wells. Ground- water level elevation data and separate-phase hydrocarbon thickness are summarized in Table 4. Soil and groundwater analytical results from this investigation are also shown on Figures 4 and 5,respectively. Analytical laboratory reports are included in Appendix C. 5.1 GEOLOGIC AND HYDROGEOLOGIC CONDITIONS Soil encountered during the May 2002 investigation included deposits of fine grained soil, including silts with sand and gravel with interbedded coarse grained deposits including silty sands and sands. These deposits appear to be underlain by a sandy lean clay at a depth of .:,. approximately 80 feet bgs. The depth to groundwater measured in wells MW-2, MW-3 and MW-4 was 32.44, 33.74, and 34.81 feet below the top of the well casing (TOC), respectively. During the May 2002 sampling event, groundwater flow appeared to be toward the east at a relatively flat gradient of approximately 0.0006 feet/feet (3.2 feet/mile). When the wells were last sampled in July 1998, groundwater flow appeared to be toward the north-east. A slight sheen was observed in MW-2 and MW-I contained approximately 0.13 inches of separate- phase petroleum. The depth to water in off-site well WFSMW-I was 34.56 feet below TOC. Water-level elevations and separate phase thickness are shown on Table 4. A potentiometric surface map is presented on Figure 5. 5.2 SOIL RESULTS Evidence of petroleum hydrocarbons(i.e., odor and/or visual presence) was first observed at depths of approximately 14 feet bgs in GMX-IB and 47 feet bgs in GMX-8 and was present to depths of approximately 80 feet bgs in both borings. Petroleum occurs at or below the current water table likely because the water table was historically lower, Petroleum hydrocarbons were not observed in soil from boring GMX-9. It should be noted that GMX-9 was advanced to a 6 Samples submitted for VOC analyzes were inadvertently run 6 days past the hold time of 7 days. \\oaklldeptdata\Doc_Safc16000s16447.00]1RcporilUS Can SoHGW Rpt.doc 8