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' • 11 March 2002 AGE-NC Project No. 95-0130 ' Page 3 of 13 ' were detected in initial ground water samples from all three wells at concentrations up to 11,000 micrograms per liter(µg/1). Analytical results of soil and ground water samples are summarized in Tables 2 and 3. Results of the December 1994 investigation were reported ' in Preliminary Investigation and Evaluation Report (PIER) dated 10 April 1995, prepared by Geological Audit Services, Inc. ' December 1995 -Three soil vapor extraction(SVE)wells (VW-1, VW-2 and VW-3)were advanced to depths of 63 feet bsg near the former UST areas;one ground water monitoring well (MW-4) was advanced to a depth of 75 feet bsg and located approximately 60 feet ' southeast (crossgradient) of the former UST area. TPH-g and BTEX-impacted soil was encountered in all three SVE wells at depths of 15 feet to 60 feet at concentrations as high as 7,400 mg/kg; petroleum hydrocarbons were not detected in soil samples collected from ' MW-4. Dissolved TPH-g was not detected in initial ground water samples collected from MW-4. However, TPH-g and benzene were detected from MW-4 subsequent sampling events at concentrations as high as 78 µg/1 and 10µg/1,respectively(Table 3).Results of the ' December 1995 investigation were reported in Corrective Action Plan (CAP), dated 20 March 1996, prepared by AGE. •• January 1996-One ground water monitoring well(MW-5)was advanced approximately 50 feet northwest (crossgradient) of the former UST area to a depth of 70 feet. TPH-g and BTEX-impacted soil was encountered at depths of 45 and 50 feet at concentrations as high as 940 mg/kg. TPH-g and BTEX-impacted ground water was detected in the initial sample from MW-5 at a concentration of 23,000 gg/1(Tables 1 and 2). Results of the January 1996 investigation were reported in the CAP. • January 1996-An 8-hour soil vapor extraction(SVE)pilot test was conducted at the site by inducing a vacuum from well VW-1B (screened 28 to 43 feet bsg); ground water was ' measured approximately 55 feet bsg. The pilot test was performed to provide vapor extraction data for proper system design of a remediation system. TPH-g and BTEX compounds were detected from influent SVE air flow samples at concentrations as high as 95,000 micrograms per liter (µg/1). Significant vacuum was measured from monitoring points VW-lA,VW-1C, VW-2A, VW-2B, VW-3A;no measurable vacuum was observed at MW-3, located 35 feet east of VW-1. Based on the observed results, a theoretical radius ' of influence for SVE at VW-1B was projected at approximately 30 feet. Results of the January 1996 investigation were reported in the CAP. ' April 2000-Five soil borings(CPT-1,CPT-1A,CPT-2,CPT-2A and CPT-3)were advanced on- and off- site to approximately 105 feet bsg utilizing cone penetrometer testing (CPT) technology to characterize the geological and hydro-geological framework and to assess ' preferential migration pathways. Laboratory analysis of grab water samples detected substantial petroleum-impact from CPT-lA and CPT-2A to depths of 105 feet bsg(Table • 4).Results of the April 2000 CPT investigation were reported in Quarterly Report-Second ' Quarter 2000, dated 31 July 2000, prepared by AGE. Advanced GeoEnvironmental,Inc.