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Methane Drainage Wells Project Plan Technical Revision I02; MDW 19-06 Page 9 of 13 wildlife. This will reduce the risk of stock and wildlife approaching the mud pits for water. DRILLING ACTIVITIES Drilling activities for the proposed methane drainage wells will include mobilizing drill equipment to the sites and drilling and setting approximately 40 feet of 16-inch surface casing into bedrock. The holes will be rotary drilled with a 12 '/a-inch diameter hole to within 250 feet of the B-Seam, then cased with 9 5/8 inch ID steel casing. Then an 8'/a- inch diameter hole will be drilled to within 120-150 feet of the B-Seam in the "relaxed zone". The 8 '/a-inch diameter drill hole may be cased with a 7 5/8-inch slotted casing, depending on the integrity of the hole. A design specific to MDW 19-06 is attached. DE-GAS INSTALLATION Passive de-gassing of the longwall panels would be accomplished by extending a non- metal stack to the surface casing, attaching a lightning arrestor to it and venting to the ambient atmosphere. Active de-gassing would require a trailer or skid mounted gas exhauster, flame arrestor, valves, and non-metal stack with lightning arrestor that would exhaust the gases to the ambient atmosphere. The trailer would be totally enclosed with Fencing and the fence gate locked to prevent public access to the equipment. The equipment would need to be approved and inspected by the Mine Safety and Health Administration (MSHA) prior to installation. MONITORING Initially, MSHA may require monitoring and inspection of the active de-gas installation twice daily after installation. It is anticipated the frequency of monitoring would decrease to a weekly monitoring and inspection of the installation, Routine maintenance will occur to the extent necessary, simultaneous with the weekly monitoring. PROPOSED DRILL HOLE PLUGGING METHODS In accordance with the Coal Program Guidance Document -Methane Drainage and Monitoring Wells, MCC will plug and abandon these MDWs per DMG Rules 2.05.4 and 4.07.3 at the minimum. A mechanical packer will be set at the lowest possible point in the well (note that subsidence damage to the casing may preclude access to the entire depth of the casing). Above this packer the hole will be plugged with CDMG approved materials to the bottom of the 5-foot cement surface cap using tremmie line. The top 5- feet of the well below the sub-surface casing cut-off point (3-feet below the surface) will be plugged with a cement cap. The top 3-feet of the casing will then be cut off and the hole filled in with subsoil. A permanent marker shall be installed on top of the plug identifying the MDW. The pad will then be reclaimed to approximate original contour. The Methane Drainage Well drilling experience for Mountain Coal Company has shown that no aquifers have yet been encountered. However, the procedures described above would serve to properly protect any aquifers that would be encountered. A drawing depicting a typical abandoned MDW is attached as Figure No. 1, Proposed GVB/MDW Hole Plugging Method.