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Mr. Robert McClellan October 1 , 2010 Page 7 include a '/4-inch brass labcock valve for sampling, and a brass identification tag with the well ID, interval, and screened depth. Forward will provide a lock, keyed the same as the locks securing existing monument boxes. Abandonment Details Five existing LFG probes, GP-8, GP-9, GP-10, GP-11, and GP-12, are to be abandoned as part of this work plan. Probe abandonment will not occur until the permitted boundary expansion has been approved. The probes and their respective depths are listed in Table 4. The following procedure shall be used to properly abandon the existing LFG probes: • The existing surface features including the concrete pad and protective casing shall be removed. • An attempt shall be made to remove the PVC probe casings by pulling them out. • The existing probe will then be drilled out using a minimum 10-inch diameter auger to remove any PVC casing and screen that could not be pulled out, and the bentonite/sand pack annular materials. Drilling will continue to just beyond the total depth of the probes listed in Table 4 and after natural materials are encountered. • A grout seal will then be placed in the boring from the bottom up using a tremmie pipe. The auger string will be removed as grouting progresses. The grout will be pumped up to the land surface. • After allowing time for the grout to set, any settlement of the grout will be filled in with concrete to the land surface. Drilling In accordance with CCR Title 27 §20925(d)(1),the probe installation and abandonment will be performed by a licensed drilling contractor. A split-spoon soil core sample will be taken at five- foot intervals and logged by either a geologist or geotechnical engineer using the Unified Soil Classification System(USCS). The total depths of the new probes are expected to be approximately 40 feet, as indicated in Table 3. The actual depth will be determined in the field depending on encountered subsurface geology and final elevations. Drill cuttings will be used as backfill material or spread on the ground around the immediate location. PRE-CONSTRUCTION ACTIVITIES Well permits are required for the LFG extraction and SVE wells, perimeter monitoring probes, and well abandonments. All appropriate permits shall be obtained by either the driller or oversight contractor prior to work beginning. In addition,the drilling locations will be marked with white paint, and Underground Service Alert(USA)will be notified as required by law a minimum of 48 hours prior to any drilling activities.