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MA soil vapor survey was conducted in March, 1998, to order to better define the extent of near- surface soil contamination This survey was followed by the drilling of two new soil bonngs to 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 31 5 feet for potential use as an air spargmg well Groundwater monitoring has taken place annually or semi-annually at this site since 1995, but was performed three times in 1999 30 PROCEDURES Upon arrival at the site, the wells were opened and allowed to equalize with atmospheric pressure A Solmst water level meter was used to measure the depth to groundwater in the wells Depth measurements were recorded on the Well Monitor Report (Appendix A) and are shown in Table 1 After water depths were measured, a Grundfos submersible pump was used to purge the wells of •� twelve gallons of water,which was stored in a DOT-approved drum in the southwest corner of the site However, VM-4 went dry after only 6 gallons had been purged During purging, a Corning meter was used to measure pH, conductivity, and temperature, and these parameters were recorded on the Well Monitor Report Well SW-1 was not purged, because the water level was near the bottom of the well and less than one gallon was present A small amount of water was also present in VT-1 at a depth of 29 78 feet, but this was probably residual water trapped in the well tip because the true water depth in the well should have been more than 31 feet, as it was in the other wells (see section 4 1) After purging, samples were collected from each well Three 40-m1 vials were collected from each, labeled, and placed in a cooled ice chest The samples were later shipped to McCampbell Analytical for analysis The laboratory report is included in Appendix B The water purged from VM-2 emitted a foul, "sewer" odor and was the color of "gray water" These characteristics were more pronounced than in earlier monitoring events, although odors had been noted on two or three previous occasions It is now clear that VM-2 is impacted by a sewer- line leak Samples have not been analyzed for fecal coliform bacteria to confirm this conclusion 3