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E 7t I15 June 2004 AGE-NC Project No 01-0877 Page 6 of 7 During the October 2003 monitoring event, ground water level in the wells was at least seven feet below the top of the well screen, Indicating that the wells were screened properly to yield representative ground water samples 1 3 4 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected In all ground water samples at concentrations ranging from 52,000 micrograms per liter(gg/1) In sample MW-3 to 77,000 µg11 In sample MW-4 BTEX compounds were detected In water samples collected from all wells, the maximum concentrations were detected In sample MW-1 at 8,000µg/l benzene, 11,000 gg/l toluene,3,500 gg/l ethylbenzene and 11,900 gg/l total xylenes 1,2-DCA and EDB were detected In the ground water samples collected from wells MW-1 through MW-3 at maximum concentrations of 24 gg/l (MW-3) and 57 µg/1 (MW-1), respectively • Concentration maps depicting the approximate distribution of dissolved TPH-g and benzene are presented In Figures 8 and 9, respectively No other target analytes were detected at or above laboratory detection limits In the ground water samples analyzed The analytical results of ground water samples collected on 09 October 2003 are summarized in Table 3 The laboratory report (CTEL Project No CT214-0310076), QA/QC report and chain-of-custody form are Included In Appendix G I 4.0. SUMMARY AND CONCLUSIONS ' The following conclusions were drawn from the results of this Investigation • The general soil stratigraphy consisted of silty clays and clayey slits from surface grade to approximately 12 feet bsg, clayey sands and silty sands from approximatly12 feet bsg to 50 feet bsg, and medium to coarse sand with gravel from 50 feet bsg to total boring depth ' One or more target analytes were detected In soil samples collected from MW1 through MW4 and B5 With exception of sample MW3-30 and B5, the absorbed contaminant concentrations Increase with depth to the total boring depth Laterally, the most significant ' concentrations (greater than 1,000 mg/kg) of TPH-g In soil Is localized between the former UST location and boring MW3, at a depth of approximately 30 feet bsg (Figure 6) • The lateral extent of petroleum-hydrocarbon Impacted soil is not defined In any direction One ' or more of the constituents TPH-g and BTEX were detected In samples collected from borings MW 1 through MW4 Advanced CeoEnvironmental,Inc