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Soil Sampling Initial soil samples were collected, at a minimum, at 5-foot intervals Soil samples retained for chemical analyses were collected in clean, brass tube liners Upon removal from the sampler, the soil samples were logged and immediately covered on both ends with aluminum foil and sealed with plastic end caps The soil samples were labeled, entered on a chain-of-custody form, placed in a cooler with ice, and transported to Sequoia Analytical, a State-certified, analytical laboratory located in Redwood City, California Soil sample preservation techniques are presented in the Field Methods and Procedures included in Appendix A Well Installation Four soil borings (MW-1 through MW-4) were completed as monitoring wells by installing 2-inch diameter, Schedule 40 PVC well casing with 0 020-inch, factory slotted well screen Well screens were placed in Wells MWA from 7 to 22, MW-2 from 7 to 25, and MW-3 and MW-4 from 7 to 22 feet below grade The annular space of each well was packed with a #3 medium grade sand placed from total depth to one foot above the top of the slotted well screen One foot of bentonite pellets were placed above the sandpack Cement grout was then placed on top of the bentonite seal to approximately 1 112 feet bgs The well casings were completed with locking well caps and locks set inside traffic- rated underground vaults The underground vaults were set in concrete The well completion details are presented on the exploratory boring logs presented in Appendix B DRILLING ACTIVITY CONCLUSIONS TPH-Gasoline was reported in only soil samples B-1-50 and B-1-90 at concentrations of 2 6 and 13 ppm, respectively TPH-Diesel was detected in soil samples B-2-5 0 and MW-2-5 0 at concentrations of 1 0 and 11 ppm, respectively Benzene was detected in soil samples B-2-5 0, B-2-9 5, MW-4-6 0, and MW-4-10 0 at concentrations ranging from 0 020 to 0 20 ppm TPH-Gasoline was detected in grab groundwater samples collected from exploratory soil borings B-1, B-2, and B-4 at concentrations of 190, 380, and 890 ppb, respectively Benzene was detected in water samples from B-2 and B-4 at concentrations of 150 and 22 ppb, respectively TPH-Diesel was detected in water samples collected from borings B-1, B-2, and B- 4 at concentrations of 13, 84, and 580 ppb, respectively Analytical reports for the exploratory soil borings are presented in Appendix D 9-8264tpvw page 5