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�$� CLEARWATER . G a v 0 Env:ronmenta( Serarcrs of benzene in soil samples collected from MW-9, MW-10 and MW-11 did not exceed 0 36 mg/kg with most of the results indicating soils below laboratory detection limits Fuel oxygenate MTBE was detected in all of the borings except MW-10 but only at very low concentrations Specifically,maximum concentration of MTBE measured was 0 038 mg/kg in MW-12 a t 65 feet bgs The soil sample results from this investigation have been tabulated and are presented an Table 1 The laboratory data sheets are presented in Appendix D The soil samples were logged on-site for lithographic characteristics The soils encountered during the drilling of MW-9 through MW-12 primarily consisted of primarily silts and sands with lesser amounts of clays, silty sands,and sandy silts These results are consistent with site sediments encountered during previous investigations The boring logs are presented in Appendix B Groundwater Sampling Results As mentioned above groundwater samples were collected from the new wells and each existing • monitoring well in June 2001 Separate phase hydrocarbons (SPH)were not detected in any of the wells monitored during the June 2001 monitoring and sampling event Results from this sampling event indicated the presence of dissolved phase petroleum-related hydrocarbons in the groundwater in the area beneath and adjacent to the former UST area Water samples collected from the wells with submersed screens (MW-1 through MW-8) were virtually free of detectable levels of contaminants Thus, the data collected from these sampling points appears non-representative of actual conditions and Clearwater will therefore, focus the subsequent data evaluation on the wells with appropriately screened wells Concentrations of TPH-G ranged from 71 gg/l in VW-3 to 19,000 µg/l in MW-12 Benzene concentrations ranged from not detectable in VW-3 to 6,600 gg/l un MW-12 Concentrations of MTBE were only detected in MW-11 at 70 gg/l and in VW-2 at 5 7 Rg/1, although detection limits for the remaining samples were elevated to 250 gg/l (MW-10 and VW-1) and 1,000 gg/l (MW-12) The groundwater quality data has been compiled and is presented can Table 2 The distribution of contaminants in the groundwater are shown on Figure 3 The laboratory data sheets are presented in Appendix D Page 6