ARCHIVED REPORTS_2008_15 - Laserfiche WebLink

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' Mr. Robert McClellan December 8, 2008 Page 8 ' Alert(USA)will be notified as required by law a minimum of 48 hours prior to any drilling activities. ' Drilling A split spoon soil core sample will be taken at five foot interval for soil logging. Subsurface geology will be logged during drilling by a qualified professional using the United Soil Classification System(USCS). The total depth of the new probe is expected to be approximately 26 feet, as indicated in Table 2. The actual probe depth will be determined in the field depending on encountered subsurface geology. Drill cuttings will be used as backfill material or spread on the ground around the immediate location. Construction Details ' Proposed construction details are shown in Figure 4. The probe casing will consist of 1/2-inch diameter or greater flush-thread schedule 80 PVC. The probe screen will consist of/i-inch diameter or greater flush-thread schedule 80 PVC 0.010-inch well screen. The bottom of the screen will be capped with a secured end cap. No glue will be used during any part the construction of the probe. After the probe is in place the borehole will be backfilled with a filter pack consisting of pea gravel to approximately 6 inches to 1 foot above the screen. A five-foot thick(minimum) layer of hydrated bentonite will be installed on top of the pea gravel to isolate the screened interval from any surface intrusion. The remainder of the borehole will be backfilled with native soil cuttings, and five-foot hydrated bentonite seal at the surface. ' The surface of the probe will be protected by installing a locking metal monument box encased in an approximately 2-ft x 2-ft concrete apron. The surface completion will include a '/4-inch brass labcock valve for sampling. FL will provide a lock,keyed the same as the locks securing existing monument boxes. Subsurface geologic conditions encountered in the field and all probe construction details will be summarized in boring logs and included as part of the installation report. ' Health and Safety Considerations Work on or near landfill sites warrants special precautions to mitigate potential combustible gas hazards,worker exposure to the trace constituents of LFG, or exposure to physical hazards that may be encountered.