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i 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 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 31 5 feet for potential use as an air sparging well 3.0 PROCEDURES The depth to groundwater was measured and water samples were collected on March 20, 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 I After water depths were measured, each well was purged of 20 gallons of water(except VM-4, which pumped dry after 6 gallons), and the purged water was tested for conductivity and temperature at 4-gallon intervals (Appendix A) After purging, two or three 40-m1 vials of water were collected from each in new disposable bailers The samples were labeled and placed in a cooled ice chest, and 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 March 20 was the same as when it was measured on December 11, 2001 (Table 1) The depth averages about 33 feet Figure 3 illustrates the piezometric surface and general direction of groundwater flow The groundwater elevation contours remain oriented in a northwest-southeast direction, and groundwater continues to flow to the northeast The hydraulic gradient is approximately 0 0024 ft/ft 4.2 Analytical Results In the fourth quarter of 2001, Total Petroleum Hydrocarbon and BTEX concentrations decreased in three of the four wells In the first quarter of 2002, concentrations increased in all four wells (except for TPH-g in VM-2) (Table 2) The increase occurred despite the fact that there was no change in the depth to groundwater or in the direction of groundwater flow The increase may be due to desorption of the hydrocarbons from the soil, no other,possible explanations are apparent 3