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E In July 1996, three soil borings were drilled and two were converted to monitoring wells Contaminated soil was encountered in two of these, and one or more hydrocarbon contaminants were detected in water samples from all three, as well as in the previously dnlled well (V',4-1) The resulting data helped to partially define the limits of soil contamination, but the limits of groundwater contamination were not reached A soil vapor survey was conducted in March, 1998, in order to better define the extens of near- surface soil contamination This survey was followed by the drilling of two new soil i onngs to collect samples to confimn the vapor results The results of the investigation were preser,ed in the Sold Assessment Report prepared by Upgradient in April, 1998 Subsequently, one of tl - borings was converted to groundwater morutor well VM-4 Groundwater morntonng took place annually or semi-annually at this site between 1995 .nd 1998 In 1999, quarterly monitoring was begun 3.0 PROCEDURES Upon arrival at the site, the wells were opened and allowed to equalize with atmospheric pressure A Solinst water level meter was used to measure the depth to groundwater in the momtoi ing 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 between twelve and fifteen gallons of water, which was stored in a DOT-approved drum in the southwest corner of the site During purging, a Corning meter was used to me isure pH, conductivity, and temperature, and these parameters were recorded on the Well Monitor Rt port After purging, samples were collected from each well Three 40-m1 vials were collected fiom each. labeled, and placed in a cooled ice chest These samples were later transported to Excel.-hem for analysis In addition, a 1-liter amber bottle was collected from each well These samples were also labeled and placed in the ice chest, and were shipped to Cytoculture Environmental Biotozhnology Laboratories in Pt Richmond, California. The laboratory reports are mcluded in Appendix B 4 0 RESULTS 4.1 Depth to Groundwater The depth to groundwater is almost exactly one foot less than it was in February(Table 1) The static water surface is 13 to 15 feet above the screened interval in the first three wells, and approximately 3 feet over the screen in VM-4 3