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GEOMATRIX and PAHs using EPA Method 8270 SIM. TPHd analyses were performed both with and with- out a silica gel preparation procedure. 5.0 OFF-SITE INVESTIGATION RESULTS The following sections describe the results from this investigation. The analytical results for soil samples are summarized in Table 1, along with historical results. Groundwater analytical results from the monitoring wells and grab groundwater locations are summarized in Table 2, along with the historical results from the monitoring wells. Groundwater level elevation data and separate-phase hydrocarbon thickness are summarized in Table 3. 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 August 2003 investigation included deposits of fine-grained soil (i.e., clays and silts with sand and gravel)with interbedded coarse-grained deposits (i.e., silty sands and sands). The depth to groundwater measured in wells MW-2 and MW-3 was 31.78 and 33.37 feet below the top of the well casing (TOC), respectively. A slight sheen (less than 0.01 inches) was observed in MW-2. During previous sampling events in May 2002 and July 1998, horizontal groundwater flow at the site was toward the east and northeast, respectively, at a relatively flat gradient of approximately 0.0006 feet/feet (3.2 feet/mile). Separate phase petroleum has been observed in MW-2 and MW-1 during each sampling event. Water-level elevations and separate phase thickness are summarized in Table 3. 5.2 SOIL Field screening results that would indicate evidence of soil affected by petroleum hydrocarbons include petroleum odor, soil staining with greenish-gray color,presence of residual petroleum hydrocarbons, and/or PID readings significantly higher than background measurements. Evi- dence of affected soil was observed at depths between approximately 32 feet bgs to 43 feet bgs in GMX-11 and approximately 38.5 feet bgs to 44 feet bgs in GMX-12. Conclusive evidence of affected soil was not observed in GMX-10. These field screening results are summarized on the boring logs included in Appendix B. Analytical data of the soil samples are summarized in Table 3 and presented on Figure 4. TPHg, TPHc,benzene, toluene, xylenes, and several PAHs were reported for the 41.5-foot sample collected from GMX-12, and were not detected in the 48.5-foot sample. Petroleum I:\Doc_Safe\6000s\6447.001\OffSite Rpt\US Can SoilGW Rpt 2003.doc 8