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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 monitor well VM-4 I 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 Thd 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 December 11, 2001 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, samples were collected from each well 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 B . 4.0 RESULTS 4.1 Depth to Groundwater and Hydraulic Gradient The depth to groundwater on December I I averaged 33 3 feet (Table 1), which is about 1 5 feet deeper than it was at this time last year and 2 feet deeper than it was in September of this year j I Figure 3 illustrates the hydraulic gradient and general direction of groundwater flow The shallow trough in the hydraulic gradient that was present in the central portion of the site in September has disappeared, and the groundwater elevation contours have returned to their relatively linear northwest-southeast pattern As a result, the groundwater flow direction has returned to the northeast 4.2 Analytical Results Total Petroleum Hydrocarbon and BTEX concentrations decreased in three of the four wells during the quarter (Table 2) Concentrations were slightly lower in VM-I and VM-3 and 20-50% lower in VM-2 However, this is still the most contaminated well Concentrations were essentially unchanged in VM-4 For the second consecutive quarter, the laboratory noted that the chromatogram for VM-4 is atypical of gasoline and is due mainly to one or two discrete peaks within the gasoline range • 3