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' 07 March 2002 AGE-NC Project No 99-0637 IPage 5 of 6 MTBE was detected in the water sample collected from CPT-3 at 81 feet to 85 feet bsg(HU5) at a concentration of 16 µg/1 The other fuel additives were not detected at or above laboratory reporting limits in the ground water samples The laboratory report(MAI Lab I D 88049, 88050, 88051 and I 88053 through 88058) QA/QC report and chain-of-custody form are included in Appendix B Analytical results of the CPT grab ground water samples are summarized in Table 1 34 LABORATORY RESULTS OF SOIL SAMPLES I One soil sample was collected during the subsurface investigation from boring CPT-1 at 35 feet bsg MTBE was detected in the soil sample at a concentration of 0 006 milligrams per kilogram(mg/kg) TPH-g,TPH-d,BTEX and the other fuel additives were not detected at or above laboratory reporting limits in the soil sample The laboratory report (MAI Lab I D 88052) QA/QC report and chain-of- custody form are included in Appendix B Analytical results of the soil sample are summarized in Table 1 4.0. SUMMARY AND CONCLUSIONS Based on the findings from this investigation, AGE concludes • Generally,fine grained silts and clays were encountered at depths between surface grade and 10 feet bsg, 20 and 30 feet bsg, 45 and 60 feet bsg and 80 feet bsg to the total depths of the bonngs Gravelly sand,sand and silty sand were observed at all other depths Geologic cross sections A-A'and B-B'were generated from CPT data collected and depict general lithology beneath the site in cross sectional views (Figure 3 and 4) • TPH-d and MTBE were detected at concentrations lust above laboratory detection limits in the water samples collected from CPT-3 from units HU2 and HU5,respectively Constituents of concern detected in ground water samples collected during the CPT investigation are Idepicted in cross sectional views A-A' and B-B' (Figure 3 and 4) • MTBE was detected at a concentration just above the laboratory detection limit in the soil sample collected from CPT-1 at 35 feet bsg (0 006 mg/kg) • The vertical extent of petroleum hydrocarbon-impacted ground water has been defined The lateral extent ofpetroleum hydrocarbon-impacted ground water in units HU2,HU4 and HU5 has been defined s Advanced GcoEnvironnkental,Inc f