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I30 March 1999 AGE-NC Project No 96-217 IPage 4 of 5 respectively Benzene, MTBE, TBA, DIPS, ETBE, TAME were not detected in any of the water I samples analyzed None of the analytes of interest were detected in the ground water sample collected from monitoring well MW-2 IAnalytical results of ground water samples are summarized on Table 4 The laboratory report (MAI Laboratory ID 98907, 98908 and 98909) and chain-of-custody are presented in Appendix B I 5 0 CONCLUSIONS IBased upon current results of the ground water monitoring and previous work, AGE concludes I0 Impacted ground water extends off-site toward the north and south, and may extend further west on-site and possibly off-site I0 Although the lateral extent of hydrocarbon-impacted ground water at the site has not been fully delineated, the concentrations of the analytes of concern in the ground water samples collected from monitoring wells MW-1 and MW-3 are low Concentrations of toluene, I. ethylbenzene and total xylenes are well below the maximum contaminant levels (MCLS) set for those compounds in drinking water An MCL for TPH-g has not been established, the detected concentrations of TPH-g are low I • A well is shown to be located approximately 400 feet north-northwest(down-gradient) of the subject property on the Union Island Quads angle, 7 5 Minute Seizes topographic neap, Ipublished by the U S Geological Survey in 1978 (Figure 1) • Hydrocarbon concentrations in soil are very low, generally undetectable • Neither benzene nor MTBE were detected in any of the ground water samples collected from the monitoring wells during the November 1998 monitoring event, and none of the analytes of interest were detected in the ground water sample collected from monitoring well MW-2 • MTBE was detected only during the I 1 July 1996 monrtol ing event by EPA Method 8020, but EPA Method 8260 analysis was not run for confirmation Analysis by EPA Method 8260 of ground water samples collected during subsequent monitoring events have not detected MTBE AGE believes that the MTBE detections of I I July 1996 were probably false positives IGround water flow direction has been toward the north-northwest during the three monitoring events I i I Advanced GeoEmiromnentar,Inc I