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LW 20 November 2003 AGE-NC Project No. 96-0263 Page 4 of 11 collected during the CPT investigation. Low concentrations of BTE&X and MTBE compounds were detected in the soil sample collected from 44 feet bsg in soil boring CPT-2 and in the grab ground water sample collected from CPT-2 between 39 to 43 feet bsg.A low concentration of benzene was detected in the grab ground water sample collected from 38 L. to 42 feet bsg in boring CPT-l. In addition to the CPT investigation, three ground water monitoring wells (MW-9 through MW-11) were installed at the site during March 2001. Target analytes were not detected in the soil samples collected from pilot borings MW-9 i. through MW-11. Ground water monitoring and sampling has been performed at the site since December 1999.Results `i of ground water monitoring are discussed in Section 6.0. and presented in Tables 2 and 4. ` 4.0. SOIL CHARACTERIZATION Boring logs recorded during AGE's site assessment investigations were used to characterize the geological and hydra-geological framework and to assess potential migration pathways. In general, the soil profile beneath the site is fairly homogeneous vertically, consisting primarily of silt, sandy silt, clayey silt, silty clay and clay. However, interbedded coarse-grained soil consisting of poorly graded sand, gravelly sand and silty sand layers were observed in soil samples recovered from several soil borings and recorded during the CPT investigation at varying depths.Figures 3 through 5 �. illustrate subsurface geologic profiles at the site. Boring logs are included in Appendix B. s- 5.0. ASSESSMENT OF HYDROCARBON-IMPACTED SOIL Between June 1998 and March 2001, soil samples were collected during UST removal activities LN (samples D-1,L-1,TIN,T2N,T1S and T2S)and from 20 soil borings(B-1 through B-7,CPT-2 and CPT-3 and MW-1 through MW-11)as part of the subsurface petroleum hydrocarbon investigation. Petroleum hydrocarbons were not detected or were detected at very low concentrations in soil samples collected from borings B-6, B-7, MW-1, MW-3, MW-6, MW-9, MW-10 and MW-11, delineating the maximum potential lateral extent of impacted soil. Furthermore, detected concentrations of target analytes were very low or below the reported detection limits in soil samples collected from total depth of borings B-3,B-6,MW-4,MW-5,CPT-2 and CPT-3,virtually defining Lo the vertical extent of impacted soil at the site. Based on the soil data collected from the site, the greatest concentrations of hydrocarbons were L. detected beneath the former dispenser and piping locations. The plume of impacted soil at the site has an estimated northwest-southeast diameter of approximately 95 feet, a northeast-southwest diameter of approximately 70 feet and appears to extend vertically approximately 44 feet bsg. L. Advanced GeoEnvironmental,Inc. i.r