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I - <br /> as gasoline), volatile aromatics (BTE&X), volatile halocarbons, lead (Pb) and ethylene <br /> dibromide (EDB) in accordance with EPA methods 8015m, 602, 601, 7420 (239.2) and 601, <br /> respectively. <br /> 4.0 FINDINGS <br /> 4.1 Groundwater Gradient and Direction <br /> I The depth to first groundwater ranges from 57 feet north of the site to 59 feet southwest <br /> P g g <br /> of the site. The data indicates a 3/4 foot rise in elevation since December of 1993. The rise <br /> in elevation is uniform thoughout the site area. Figure 4 is a groundwater gradient map, <br /> based upon the data collected on March 28, 1994. Groundwater flow is south-southwest in <br /> the area. This is consistant with historical gradients. <br /> 4.2 Groundwater Contamination <br /> IPetroleum hydrocarbons were detected in samples from all wells except MW-13. TPH as <br /> gasoline ranged from 80 ppb (MW-6) to 5,400 ppb (EW-1). Detectable BTE&X <br /> I concentrations ranged from 0.59 ppb (toluene, MW-8) to 520 ppb (xylenes, EW-1). The <br /> analytical results are summarized in Table 3.The laboratory results and chain-of-custody are <br /> included in Appendix A. <br /> Lead was detected in groundwater samples from wells MW-12, MW-13, and MW-14 at <br /> concentrations of 0.021 ppb, 0.023 ppb and 0.008 ppm respectively. The analytical results are <br /> summarized in Table 4. The laboratory report and chain-of-custody are included in <br /> Appendix A. <br /> I1,2-Dichloroethane was detected in MW-8, MW-9, MW-13, MW-14 and EW-1 at <br /> concentrations of 5.1 ppb, 70 ppb, 3.3 ppb, 7.0 ppb and 22 ppb, respectively. No EDB or <br /> I other volatile halocarbons were detected in any of the water samples. The analytical results <br /> are summarized in Table 4. The laboratory results and chain-of-custody are included in <br /> Appendix A. <br /> 5.0 CONCLUSIONS AND RECOMMENDATIONS <br /> 5.1 Groundwater Depth and Flow Direction <br /> Groundwater elevation has increased about 0.75 feet throughout the site (see Table 1). A <br /> I two-foot decrease in groundwater elevations was noted during the previous sampling period <br /> (December 1993). The recent fluctuations are in accordance with seasonal variations of <br /> I groundwater depth in the region. The groundwater flow direction continues to be to the <br /> south-southwest. <br /> G-60-1 A.,W SemiM[., 10 <br /> 13114-9401DM QA3 <br /> r <br /> I <br />