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collect samples to confirm the vapor results The results of the investigation were presented in the Soil Assessment Report prepared by Upgradient in April 1998 Subsequently, one of the borings was converted to groundwater momtor well VM-4 In August 1999, Upgradient installed two remediation test wells within the mapped zone of soil contamination However, no hydrocarbons were detected in any of the soil samples collected from these wells One of the wells (VT-1) was screened with 4-inch PVC casing from 15 to 30 feet for future use in soil vapor extraction testing The other well (SW-1), was screened with 2-inch PVC casing from 29 5 to 315 feet for potential use as an air sparging well 3.0 PROCEDURES The depth to groundwater was measured and water samples were collected on September 11, 2002 The wells were opened and allowed to equalize with atmospheric pressure before the depth to groundwater was measured Depth measurements were recorded on the Well Monitor Report (Appendix A) and are shown in Table 1 After water depths were measured, each well was purged and tested for electrical conductivity and temperature at 2-to-3 gallon intervals (Appendix A) After purging, two 40-m1 vials of water were collected from each well in new disposable bailers The samples were labeled and placed in a cooled ice chest, and later transported to Excelchem / Environrnental Laboratory�for analysis The laboratory report is included in Appendix B 4.0 RESULTS 4 1 Depth to Groundwater and Hydraulic Gradient The depth to groundwater on September I 1 was on average about 17 inches greater than when it was measured on June 6 This is the first significant change in the water depth since December 11, 2001 (Table 1) The depth averages about 35 feet Figure 3 illustrates the piezometric surface and general direction of groundwater flow The piezometric surface slopes in a generally easterly direction, but may not be perfectly planar across the site Slight differences in elevation suggest that the water table may be slightly uneven, and the elevation contours appear to arc, forming a slight depression between VM-4 and VM-3 However, over such a short distance,the water table is essentially planar 4.2 Analytical Results The September analytical results are summarized in Table 2, and Total Petroleum Hydrocarbon and total BTEX concentrations are graphed against time for VM-2 and VM-1 in Figures 4 and 5 Figure 4 illustrates that there has been a trend of increasing concentrations in VM-2 since monitoring began in 1996 In the Second Quarter 2002 Report, we observed that concentrations have generally peaked during the third quarter of the year and we predicted that concentrations 3