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was measured Depth measurements were recorded on the Well Monitor Report (Appendix B) Because the water depth was 35 feet or more, well VM-5 was dry The wells were purged after the water depth was measured Due to the low static water level, most wells purged poorly or went dry after Just a few gallons were pumped However, at least 25 gallons were pumped from VM-2 in an effort to determine whether purging this well more thoroughly would remove accumulated hydrocarbons and yield a lower concentration that might be more representative of true concentrations in the aquifer The purged water was stored in 55-gallon drums in the southwest corner of the property Water samples were collected from all wells except VM-5 Two 40-m1 vials were collected from each, labeled, and placed in a cooled ice chest The samples were later transported to Excelchem Environmental Laboratory for analysis The laboratory report is included in Appendix C The new wells were surveyed on April 17' The casing elevations were then used to determine the elevation of the static water level in each well When the data were contoured, the gradient from VM-7 to VM-1 appeared to be anomalously steep, suggesting that there was an error in the survey data for VM-7 This well was re-surveyed on April 28, and the elevation was within 0 01 of a foot of the previous measurement Hence, the anomalously steep gradient is apparently real The results are discussed further below 4.0 RESULTS 4.1 Depth to Groundwater and Hydraulic Gradient The depth to groundwater on April 15 was between 35 and 36 feet, and was just a few inches shallower than when the wells were last monitored on November 20, 2002 (Table 1) The calculated elevation of the water table is approximately 20 feet below sea level Figure 3 illustrates the hydraulic gradient and general direction of groundwater flow In previous reports we have noted that the contours form an arcuate pattern and slope eastward The high water level in VM-8 makes this eastward arc even more pronounced, because the elevation in VM-8 is higher than in any other boring except for VM-7 This was not expected, based on prior mapping, the location for VM-8 was thought to be downgradient of the dispenser island at Valley Motors, and perhaps downgradient of VM-4 and/or VM-2 Assuming that the groundwater elevation data for VM-Y and VM-7 are correct, the hydraulic gradient west of M-1 is 0 016 ft/ft This is relatively steep, and is 4 times as steep as the gradient between VM-1 and VM-4 (0 004 ft/ft) Although elevation anomalies do occur in paved areas, such a large difference over such a small distance is unusual If the anomaly is real, one possible explanation is that water might be leaching into the ground from a nearby underground utility line, raising the water level in VM-7 In this regard, a city sewer line is present within a few feet of this well As noted in previous reports, a sewer odor has frequently been noted in the . groundwater purged from VM-2, so the possibility of a sewer leak is real Another possible 4