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Mr. Robert McClellon October 1 , 2010 Page 3 WORK PLAN TO INSTALL LFG EXTRACTION WELLS AND SOIL VAPOR EXTRACTION WELLS Proposed System Improvements Forward proposes to install 15 LFG extraction wells and 10 SVE wells. Forward has documented elevated LFG concentrations along the southwestern border of the site. The proposed wells will increase LFG recovery at the site. Nine vertical LFG extraction wells are proposed for the Forward Unit, and six vertical LFG extraction wells are proposed for the Austin Road Unit. The SVE wells will be installed on an east-west trending line along the southern border of the Forward Unit. The 15 LFG extraction wells will be installed in waste and will increase LFG extraction within the waste units. The SVE wells will be installed in native soil, and will extract gas that migrates beneath the liner of the Forward unit from the Austin unit. The SVE wells will create a barrier along the southwestern compliance boundary that will aid in capturing LFG that has migrated towards the southwestern border. All proposed wells will be connected to the existing headers on site, which will route any collected LFG to a flare for destruction. The locations of the proposed LFG vertical extraction wells and SVE wells are shown on Figure 1, and on the design plans in Attachment B. Proposed Construction Details Forward is proposing to install 15 LFG extraction wells and 6 SVE wells. Proposed construction for the LFG extraction wells and the SVE wells are provided in Figures 2 and 3. The well details for the Forward Unit wells are listed in Table 1 and for the Austin Unit wells are listed in Table 2. Typical well completion diagrams are provided as Figures 2a and 2b, for the Forward and Austin Units, respectively. For the Forward Unit extraction wells, a drill-rig capable of drilling a large-diameter hole, will advance a 35-inch borehole through waste to the depth listed in Table 1 and in the specifications (Attachment B). Once the target depth is reached, a six-inch well will be constructed. The well casing will consist of SDR-11 HDPE pipe, and the perforated section will have 4-1/2 inch machine-drilled perforations (see specifications for hole spacing and offset—Attachment B). The HDPE pipe joints and bottom well cap for each well shall be joined using butt fusion. Each well shall be installed in the borehole to the depth listed in Table 1, which should be approximately one foot above the total boring depth. One to three-inch washed non-carbonate gravel shall be installed to at least two feet above the perforated zone. Approximately one foot of clean, soil-plug Geonet with heat-bonded geotextile shall be installed above the gravel. Approximately two feet of a hydrated bentonite seal shall be installed above the soil plug. Soil will be installed above the bentonite layer to approximately two feet below the waste/soil interface. A bentonite layer will be installed above the soil layer and will be approximately two feet thick, extending at least six inches above the soil/waste interface. Soil will be installed above the bentonite layers to ground surface. During installation of the materials,the well installer shall use a weighted measuring tape to verify proper placement of the materials.