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1 July 20, 2001 2001-0103-01 Page 2 of 7 • Site Maps Lateral and vertical plume definition in soil and groundwater is complete as shown. A site map showing locations of former tank systems, excavation limits, sampling locations, soil borehole locations, buildings, and streets is presented in Figure 2. Monitoring and soil vapor extraction well locations, the most recent (first quarter 1999) and historically representative groundwater flow direction and gradient data are presented in Figure 3. A cross-section depicting lithology, historic depths to groundwater and excavation limits are shown in Figure 4. The surface trace of the cross section is shown on Figure 5. Soil Disposition & MonitorinLy Well Fate Stockpiled soil from excavation and soil boring activities has been removed from the subject site and treated or disposed of in accordance with local or state directives and guidance. Monitoring wells MW-3 through MW-5 and MW-9 through MW-12, were pressure grouted with neat cement under permit on February 14, 2000. Stratus field personnel located an unknown 4-inch diameter monitoring well (possibly MW-2) during a site reconnaissance on February 14, 2000. As directed by PHS/EHD, the monitoring well was also pressure grouted with neat cement. Only groundwater monitoring wells MW-1, MW-13, MW-14 and AS-1 remain to be destroyed. Remaining wells will be properly destroyed under permit following site closure to achieve no further action certification. Dztz Tabulated data of all soil boreholes, sample collection depth including sample dates, and analytical data are presented in Table 2. Tabulated data of all groundwater elevations or depth to water including sample dates and analytical data are presented in Table 3. Confirmation Sampliniz At the time monitoring well MW-13 was installed in 1992, a petroleum sheen was noted on the groundwater. A sample was collected at 85 feet below ground surface (bgs) and petroleum hydrocarbon odors were noted on the soil sample collected from 90 feet bgs. Historically, first encountered groundwater has been as deep as 106 feet bgs. Since that time, soil vapor extraction (SVE) and limited over-excavation have been completed at the subject site. On September 10, 1999 a Stratus geologist observed the completion of one confirmation soil borehole to a total depth of 100 feet bgs as directed by PHS/EHD. The geologic log of the boring (B-17) is presented in Appendix A. Groundwater was encountered at approximately 53 feet bgs. Soil samples recovered from 55 to 75 feet bgs may have been disturbed due to heaving sand conditions in the borehole. \\Front\project file\Teichert\Stockton-103\Reports\Teiehert Stockton Closure Report 070Ldoc