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24HS-ol through 24HS-03 Wells Project Plan Minor Revision 319 Page 8 of 11 pits will be designed to contain the run-off from a 25-yeaz 24-hour event and will be constructed in native soil. Mudpit designs and calculations for 1.0 foot of freeboazd have been previous ly approved by the CDMG. Water for the drilling operations will be pumped to the drill sites from the North Fork of the Gunnison using high-pressure hose. 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 40 feet of 16-inch surface casing into bedrock. The holes will be rotary drilled with a 7-inch diameter hole to the B- Seam, then cased with 4 or 5 inch ID steel casing, A depiction of a typical completed well will be forwarded to the CDMG along with the typical plug and abandonment diagram. MONITORING Initially, MSHA may require monitoring and inspection of the wells 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 well. The pad will then be reclaimed to approximate original contour. The Methane Drainage Well and other 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.