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explanation for the anomalous gradient is that the static water level in VM-7 did not equilibrate with atmospheric pressure before the level was measured Further monitoring may help to resolve this question 4.2 Soil Analytical Results None of the ten soil samples from the new wells contained petroleum hydrocarbons above the detection limits (Tablq 2) Previous mapping had indicated that these wells were beyond the limit of soil contamination, so these laboratory results were expected As shown in Table 2, only three borings that have been drilled since 1995 have encountered impacted soil, this implies that a relatively small area in the vicinity of the former dispenser island is impacted 4 3 Water Analytical Results Total Petroleum Hydrocarbon and BTEX concentrations increased in two of the four original wells In VM-1, the concentration of benzene and other volatile aromatic hydrocarbons remained low, but the Total Petroleum Hydrocarbon (TPH-g) concentration rose to 1,600 µg/1 (parts per billion), which is the highest it has been since June 2001 (Table 3) However, the laboratory noted that "the sample chromatogram does not match the standard gasoline chromatogram All peaks were integrated within the gasoline range The result is an estimated value " Because several chlorinated non-petroleum hydrocarbons were detected in this well in the mid-1990's, it is possible that the high TPH-g concentration and dissimilarity to the standard chromatogram is due to the inclusion of significant concentrations of these non-gasoline hydrocarbons The TPH-g concentration in VM-2 doubled, and there were also substantial increases in benzene, toluene, and ethylbenzene Hence, this implies that the extended purge of this well did not lead to a reduction in hydrocarbon concentrations Figure 4 illustrates the historical record of samples from VM-2, and it is evident that this well remains on a trend of increasing concentrations The concentration of all analytes declined below the detection limits in VM-3, and all decreased in VM-4 as well Overall, concentrations in this well fluctuate frequently and have developed no consistent pattern over time, but have been much lower than in VM-2, which is only 25 feet away Petroleum hydrocarbons were also detected in each of the samples from the three new wells Concentrations in the gasoline range ranged from 92 ppb in VM-8 to 440 ppb in VM-7 Benzene was detected in VM-6 and VM-7, but not in VM-8, which may indicate that the gasoline in VM- 8 is degraded The results from the new wells are not easily reconciled with the groundwater flow direction As shown in Figure 3, VM-8 is upgradient of the dispenser island at Valley Motors, and is therefore not in the flow path of contaminated groundwater Further, VM-6 is J downgradient of both VM-4 and VM-8, and concentrations should therefore be lower than in either of these wells Due to the difficulty of correlating the groundwater flow direction with the distribution of hydrocarbons, no map of the dissolved-phase plume is included in this report 5