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1 1 21 December 2001 ' AGE NC Project No 95-0143 Page 4 of 5 ' 4 1 GROUND WATER ELEVATION AND GRADIENT ' The elevation of ground water in the twelve wells was calculated by subtracting the depth to water from the surveyed casing elevation (Table 1) Ground water elevations decreased in the monitored wells an average 0 95 feet between the August 2001 and November 2001 monitoring events Ground ' water was within the screened intervals ofMW-10,MW-15, MW-16, MW-17,MW-22,MW-23 and MW-24 and inferred to be within the screened interval of each vapor well Ground water ranged from 0 24 feet to 5 86 feet above the screened interval in the other seven monitoring wells The ' approximate flow direction was toward the north-northeast with a gradient of 0 001 feet/feet at the subject property Ground water elevation contours for the November 2001 monitoring event are illustrated in Figure 3 4 2 ANALYTICAL RESULTS OF WATER SAMPLES 1 During the November 2001 monitoring event, TPH-g was detected in samples collected from monitoring wells MW-3,MW-6, MW-7 and MW-9 at concentrations ranging from 180 µg/l(MW-7) ' to 150,000 gg/l (MW-3) BTEX compounds were detected in wells MW-3, MW-6, MW--7 and MW-9 at concentrations as high as 35,000 µg/l toluene (MW-3) TBA was detected in the sample collected from MW-24 at a concentrations of 73 }tg/l MTBE, DIPE, ETRE, TAME, ethanol and methanol were not detected in samples collected from the site during the November 2001 sampling event Figure 4 illustrates the approximate extent of TPH-g and benzene contamination in ground water Measurable free product was not encountered in an of the wells on the site Analytical results of p y yt ground water samples collected during the November 2001 monitoring event are summarized on ITable 2 Analytical results of historical ground water samples are summarized on Table 3 The laboratory report (MAI Laboratory IDs 83611 through 83622) and chain-of-custody forms are included in Appendix B 5.0. SUMMARY/CONCLUSIONS Based upon data collected from the site, AGE concludes • Ground water elevation decreased approximately 0 95 feet between August 2001 and November 2001 Ground water elevation was within the screened interval of MW-10, MW-15, MW-16, MW-17, MW-22, MW-23, MW-24 and the five vapor extraction wells, • but above the screened interval of the other five monitoring wells The inferred ground water flow direction remains variably toward the north to northeast at the site I Advanced GeoEnvironnientai,Inc