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as �, . 02 April 2004 AGE-NC Project No 95-0143 Page 3 of 4 MW-17 and MW-22 through MW-24 Ground water ranged from 138 feet to 4 79 feet above the screened interval in the other four monitoring wells The elevation of ground water in the twelve wells was calculated by subtracting the depth to water from the surveyed casing elevation (Table 1) The average ground water elevation was 8 61 feet below mean sea level (MSL), a decrease of 0 09 feet since the August 2003 monitoring event The inferred ground water flow direction was toward the north-northeast with a gradient of 0 002 foot/foot (ft/ft) Ground water elevation contours for the October 2003 monitoring event are illustrated in Figure 3 3 2 ANALYTICAL RESULTS OF WATER SAMPLES During the October 2003 monitoring event, TPH-g was detected in samples collected from monitoring wells MW-3,MW-6,MW-7,MW-9,MW-15 and MW-22 at concentrations ranging from 69 micrograms per liter(µg/1) in sample MW-15 to 200,000 µg/I in sample MW-3 Various BTEX compounds were detected in the same wells at concentrations as high as 6,600 µg/1 of benzene, 49,000 µg/1 of toluene, 4,400 µg/1 of ethylbenzene and 30,000 µg/1 of xylenes, in sample MW-3 Figure 4 illustrates the approximate extent of TPH-g and benzene contamination in ground water Target analytes were not detected in the ground water samples collected from monitoring wells MW-10, MW-14, MW-16, MW-17, MW-23 and MW-24 Analytical results of ground water samples collected during the October 2003 monitoring event are summarized on Table 2 Analytical results of historical ground water samples are summarized on Tables 3 and 4 The laboratory report(MAI Lab IDs 0310498-001 through 0310498-012)and chain- of-custody forms are included in Appendix B 4.0. SUMMARY/CONCLUSIONS Based upon data collected from the site, AGE concludes • The average ground water elevation was 8 61 feet below mean sea level (MSL), a decrease of 0 09 feet since the August 2003 monitoring event The inferred ground water flow direction was north-northeast at a gradient of approximately 0 002 fL/ft • Ground water was within the screened intervals of MW-10, MW-14 through MW-17 and MW-22 through MW-24,but ranged from 13 8 feet to 4 79 feet above the screened interval in the other four monitoring wells • TPH-g and BTEX compounds were detected in MW-3,MW-6,MW-7,MW-9,MW-15 and MW-22 The highest concentration of TPH-g and BTEX compounds were detected in Advanced GeoEnvironmentat,Inc