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. 4 3 2 Water Samples Groundwater samples 1HP-2 and 1HP-3 and VM-1 through VM-3 were analyxed for TPH-g, TPH-d, BTEX, and MTBE, and VM-i through VM-3 were also analyzed for chlorinated hydrocarbons, which had previously been detected in VM-1 The results are summanzed in Tables 2 and 3, and the full laboratory report is included in Appendix B Gasoline was detected in VM-1, VM-2, and HP-2 MTBE was detected in 1HP-2, VM-1, VM-2, and VM-3, and BTEX compounds were detected in VM-1 and VM-2 A very low xylene concentration was also reported in VM-3, but this is considered questionable in light of other results from this well Although Inchcape Testing Services reported that diesel was present in the water sample from VM-1 in September and October 1995, diesel was not detected by Excelchem with any degree of certainty in any of the July water samples Excelchem noted that it may have been masked by gasoline in VM-1, but this seems somewhat unlikely in view of the fact that gasoline was detected at a much higher concentration in VM-2, yet the laboratory did not feel that diesel was masked in that sample Although chromatogram peaks within the diesel range were detected in the hydropunch sample from HP-2, Excelchem noted that the chromatgram did not resemble the typical diesel 92 standard, suggesting that these peaks might represent degraded gasoline As Table 3 shows, four of the five chlorinated hydrocarbons that were detected in VM-1 in October 1995 were again detected, along with one new compound (bromodich loromethane) Concentrations range from ten to twenty tunes higher than those previously reported Three of these halocarbons were detected in VM-2 at 5 to 10% of their concentrations in VM-1, the fourth(cis-1,2-dnchloroethane) was detected at a higher concentation, and fifth(bromodichloromethane)was not detected One of the four (tetrachloroethene)was also detected in VM-3, but at only 1% of its concentration in VM-1 4.4 Depth to Groundwater and Groundwater Gradient Appendix C shows the depth to groundwater on September 11 and October 12, 1995, and July 8, 1996 The water level rose nearly 6 feet between October and July, and presently averages 43 6 feet (Table 4) Figure 4 is a contour map showing the elevation of the groundwater surface on July 8 On that date, the water surface sloped to the east at a gradient of 0 002 ft/ft Flow in this direction would carry contaminants from the vicinity of VM-1 and VM-2 toward HP-2 A 5.0 CONCLUSIONS AND RECOMIIMND TIONS This investigation has provided additional information regarding the extent of soil and groundwater contanunation beneath the site, and provided the first site-specific information about the direction of groundwater flow Samples from VM-2 indicate that the depth range over which soil contamination is present is greater than previously shown Although contaminants may be limited to a depth of about 25 5 A