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fl GM'o rca(Technics Inc Page 4 Site Characterization Report Marct's Property September 18, 2000 i The site exhibits a primarily clayey geology The clay is typically brown with the color changing to a gray-green at depths of 90-95 feet bgs in boring MW-5 (MW-105) Minor ' sand layers/lenses, pebbles, black organics, and iron staining are occasionally present in both boring locations • A hydrocarbon odor was readily detectable in soil samples from both MW-5 (MW-105) ' and MW-6 • Groundwater level stabilized in the boreholes at approximately at 59 feet bgs See Appendix B, Boring Logs for more information The soil boring logs and well ' construction dtagrains of wells MW-1 through MW-3 from Wm J Hunter & Associates are also included in Appendix B 4.0 CONCLUSIONS & RECOMMENDATIONS Based on our interpretation of the data collected over the course of this subsurface investigation, GTI have reached several conclusions These c premise that the data we considered, although incompleteare representative of actual site are based on the conditions We acknowledge that there may be undiscovered conditions, which would upon their consideration, change our interpretation and thus our conclusions Our recommendations are based on our knowledge of site conditions, and on the state and limitations of subsurface investigative technology 41 Conclusions ' Geological Technics Inc , taking into consideration the data obtained from this investigation and from the data compiled during previous soil and groundwater investigations and the regular groundwater monitoring events, makes the following conclusions 1 The soil plume extends to the southwest and northwest of the former USI' field According to the Wm J Hunter & Associates' "Report Covering Results of Placement of Monitoring Wells", October 1997 correspondence, no contamination was detected in soil ' or water from wells MW-2 and MW-3 This suggests that the highest contamination is limited to the area of the former UST field and minor contamination has spread laterally to the southwest and northwest Wm J Hunter & Associates' soil and groundwater data ' are included in Appendix A 2 Groundwater samples from MW-5 and MW-6 showed contamination due to the diesel detected at the 55 feet bgs level (approaching the capillary fringe) in both locations Refer to the groundwater monitoring report submitted separately 4.2 Recommendations Geological Technics Inc makes the following recommendations based on the conclusions outlined above I Groundwater monitoring should occur for four quarters to determine the contaminant and groundwater direction trends before any decisions are made regarding further investigation All of the wells have been surveyed to a common datum and this should ' account for greater confidence in site data