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24HGI E3. SXC Project Plan Minor Revision 317- Revision Page 8 of 11 • Use of mud pits on or neaz the drill pad excavated in native soil. Mud pit dimensions would be 41' x 41' x 8' to acconunodate cuttings with 25% swell, the run-off associated with a 2 acre drill pad and 10 yeaz, 24-hour storm event and 1-ft of freeboazd. Mud pit designs and calculations for 1.0 foot of freeboard have been previously approved by the CDMG. • Hauling cuttings off the project site and depositing in the Refuse Pile Expansion area. As the mud pits will be excavated into native soil, mud pit slope failure is not a concern. Water for the drilling operations will be pumped to the drill sites from the mine dewatering polishing pond using high-pressure hose in combination with frac tanks and high-pressure pumps. Mountain Coal Company, L.L.C. owns water rights for these water resources. DRILLING ACTIVITIES Drilling activities for the proposed methane drainage wells will include mobilizing drill equipment to the sites and drilling and setting approximately 1,000 feet of 7-inch surface casing through bedrock to a zone in the coal seam. The holes will then be sampled and then a remote seal constructed with concrete in the B-Seam. A depiction of a typical completed well and remote seal will be forwazded to the CDMG along with the typical plug and abandonment diagram. MONITORING Currently, MSHA is requiring monitoring and inspection of the wells twice daily after installation. It is anticipated the frequency of monitoring would decrease as the pumping for a remote seal commences. Routine maintenance will occur once the seal is constructed. 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 mazker shall be installed on top of the plug identifying the well. The pad will then be reclaimed to approximate original contour.