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16 SOFA Environmental Technology Inc — .. ' The soil encountered in MW-7 from the surface to approximately 10 feet bgs was a damp, very stiff silty clay (CL) A loose to dense, damp, silty sand (SM) was encountered to a depth of approximately 25 feet bgs A damp, dense silty ' to sandy clay (CL) with some silty sand (SM) was encountered to a depth of approximately 50 feet bgs From 50 to 70 feet bgs. a loose to dense, damp to wet silty sand to silty coarse sand( SP-SM) was encountered No soil samples were collected below 70 feet bgs. In MW-8, a damp silty clay was encountered to 5 feet bgs From 5 to 25 feet bgs a medium dense, damp, silty sand was present A dense to hard silty sand (SM) to silty clay (CL) was encountered at 30 feet bgs From 35 to 40 feet bgs, a stiff, damp, silty clay (CL) was present From 40 to 50 feet bgs a dense, damp, silty sand (SM) grading to a silty clay(CL) was encountered At 60 and 62 5 feet ' bgs a dense, damp to wet silty sand (SM) was present From 65 to 70 feet bgs a dense, wet, coarse sand (SP-SM) was present ' Groundwater was first encountered at 63 and 65 feet bgs in MW-7, and MW-8, respectively. The boring logs are presented in Appendix A- 4.3 Soil Analytical Results ' Fifteen soil samples were collected from each monitoring well (MW-7 and MW- "8)—Erevven soil samples from MW-7 and ten soil samples from MW-8 were analyzed for TPH-g, BTEX, extractable hydrocarbons, TRPH (418 1), and TRPH (413 2) The soil sample analytical results of the previous consultants and SOTA's are presented in Figure 3, which clearly demonstrates that the areal -pdent of soil contamination has been delineated ' The soil samples collected from MW-7 at 25 and 30 feet bgs had TPH-g concentrations of 1,200 and 24 ppm, respectively Soil samples containing ' extractable hydrocarbons were encountered between 15 and 30 feet bgs, with the highest concentration of 680 ppm at 20 feet bgs Benzene was detected in relatively low concentrations at 25 feet, and between 63 and 68 5 feet bgs Toluene was also detected in soil samples between 15 and 60 feet bgs ' Detectable concentrations of ethylbenzene and total xylenes in soil were present in samples collected at 25 and 30 feet bgs. TRPH, both 418 1 and 413 2 were detected at 15 and 25 feet bgs In MW-8, toluene was present in all of the soil ' samples analyzed, except MW-8 at 65, in low concentrations All other analytical results for MW-8 were below laboratory detection limas The analytical results are presented in Tables 1 and 2 The laboratory reports with chain-of-custody documentation are presented in Appendix B 4.3,t "Fingerprint" Characterization ' A soil sample collected from the 'off-site" groundwater monitoring well MW-7 at 20 feet bgs, was analyzed by Friedman & Bruya, Inc , of Seattle Washington in order to identify (fingerprint) the type of constituents present in the soil sample 6