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This boring (TT-1 in Figure 2) was then completed as a groundwater monitoring well by installing 25 feet of slotted PVC casing between the depths of 75 and 50 feet Well construction details are shown in the boring logs Borings TT-2, TT-3, TT-HP-1, and TT-HP-2 were drilled between February 12 and February 16 TT- 2 and TT-3 were sampled at 5-foot intervals, drilled to a depth of 75 feet, and completed as groundwater monitoring wells TT-HP-1 and TT-HP-2 were drilled to approximately 54 feet and sampled at 5-foot intervals beginning at a depth of 25 feet A hydropunch was used to collect a groundwater sample from both borings at a depth of 55 feet Water samples were transferred from the stainless steel bailer to 40-m1 sterilized vials and 1-liter amber bottles and refrigerated Both bonngs were then backfilled to the surface with cement grout to eliminate the potential for downward leaching of contaminants Twenty-five soil samples were selected from the five borings for laboratory analysis These were transported under chain-of-custody to Excelchem Laboratories in Roseville, California The laboratory report is included in Appendix B 3.3 Well Surveying and Sampling The wells were surveyed on February 20 Casing elevations were measured to the nearest 0 01 foot T- 1 was used as a reference point for TT-2, TT-3, and the domestic well (DM-1) These elevations are ashown in Table 1 A Solinst water level meter was used to measure the depth to groundwater in the monitoring wells, and a Xi-tech oil-water interface probe was used to measure the water depth in the domestic well Depth measurements were recorded on the Well Monitor Report (Appendix C) and are shown in Table 1 The total depth of the wells was also measured and recorded After water depths were measured, a Grundfos Redi-flow 2 submersible pump was used to purge and develop the wells Approximately 30 gallons of water were pumped from each monitoring well and stored in plastic barrels Approximately 55 gallons were pumped from DM-1 The four drums are presently stored on site After purging, new disposable bailers were used to collect samples from each of the four wells Two 40-m1 vials and one 1-liter amber bottle were collected from each well, placed in a cooled ice chest, and transported to Excelchem for analysis The laboratory report is included in Appendix B 4.0 RESULTS 4.1 Site Geology Two geologic formations were recognized in the core from boring TT-1 and correlated from this 4