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' .4 November 2002 AGE-NC Project No 95-0143 Page 3 of 4 ' sample MW-3 Figure 4 illustrates the approximate extent of TPH-g and benzene contamination in ground water r MTBE was not detected in the analyzed ground water samples collected during the September 2002 sampling event ' Measurable free product was not encountered to any of the wells on the site Analytical results of ground water samples collected during the September 2002 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 0210001-001 through 0210001-005) and chain-of-custody forms are included in Appendix B 4.0. SUMMARY/CONCLUSIONS Based upon data collected from the site, AGE concludes 0 The average ground water elevation was 7 71 feet below mean sea level (MSL), a decrease of 1 08 feet since the May 2002 monitoring event The inferred ground water flow direction was northeast at a gradient of approximately 0 002 foot/foot 0 Ground water was within the screened intervals of MW-10, MW-15, MW-16, MW-17, MW-22, MW-23 and MW-24, but ranged from 0 01 feet to 5 63 feet above the screened interval in the other five monitoring wells • TPH-g and BTEX compounds were detected in MW-3, MW-6 and MW-9 at maximum concentrations of 160,000 µg/1 TPH-g and 4,800 µg/1 benzene, 47,000 µg/1 toluene, ' 4,200 µg/1 ethylbenzene and 25,000 µg/1 xylenes, in sample MW-3 The concentrations of BTEX compounds are significantly above the DHS's Maximum Contaminant Levels for BTEX in drinking water ' 0 MTBE was not detected in samples collected from the site during the September 2002 sampling event I I5.0. RECOMMENDATIONS Based upon data collected during the September 2002 and previous sampling events, AGE ' recommends 1� ' Advanced GeoEnvi ron mental,Inc 1