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4 <br /> Ms. Wendy Arano Project No. 809251 <br /> July 26, 2000 <br /> Page 3 <br /> approximately 67 feet at B-3. In boring B-3, interbedded clay, silt, and silty sand were <br /> present from 67 feet to the total depth of 82 feet bgs. The interbedded deposits at B-3 <br /> suggest the clay is grading laterally into coarser grained materials along the depositional <br /> margin. The purpose of the exploration program was to determine groundwater was <br /> perched on the clay unit to the west of well MW-5 <br /> Soil samples collected from the clay unit were damp to moist. Samples yielded minor <br /> amounts of moisture when manipulated (ie. a touch of moisture),but saturated conditions <br /> were not encountered. Borings B-1 and B-2 drilled on June 15 were left open overnight, <br /> and no measurable amount of water was present on June 16. Boring B-3 was left open <br /> for approximately 45 minutes after reaching the target depth and water did not <br /> accumulate in the boring. Because the three borings were dry, no groundwater grab <br /> samples were collected. Therefore, it is apparent that the perched groundwater zone <br /> encountered at MW-5 does not extend to the west, and likely pinches out midway <br /> between MW-5 and B-1. <br /> SHALLOW ZONE WATER LEVELS <br /> Shallow zone water levels were collected as requested by the RWQCB concurrent with <br /> drilling on June 15, 2000 and 72 hours after completion of drilling on June 19, 2000. <br /> Jun oundwater levels in monitoring wells MW-4, MW-5 and SB-1 were 11.23, <br /> 6666.655 and 38. bgs. respectively. June 19 groundwater levels in monitoring wel s <br /> MW-4, MW-5 and SB-1 were 1;-=%142, 66.87- 3 <br /> and 8.74 bgs. respectively. Shallow zone <br /> water levels are summarized on Table 1 and field sheets are presented in Appendix A. <br /> MONITORING WELL AND GAS WELL SAMPLING <br /> Monitoring well MW-5 and gas wells GW-1 through GW-3 were sampled on <br /> June 15,2000 concurrent with drilling activities to provide additional data for evaluating <br /> the relationships between VOCs in landfill gas and groundwater impacts. <br /> MW-5 Sampling and Analysis <br /> MW-5 was purged and sampled using PVC and teflon bailers, respectively. The <br /> groundwater sample was submitted to Sequoia Analytical and analyzed for VOCs using <br /> USEPA Method 8260B. <br /> Twelve VOCs tect d in the groundwater sample. Concentrations of seven of the <br /> detected VOCs were estimated trace values because they below the method <br /> reporting limits. CE was detected at 4.93 parts per billion (ppb). Analytical results are <br /> SAC:\N:\Consulting\data\Shared\Projects\PJ8\809251.aa.doc-00\ta:1 <br /> 809251 <br />