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Methane Drainage Wells Project Plan <br />Technical Revision 101; Holes 19-09, 19-10 and 19-11 <br />Page 9 of 14 <br />i.e. placement of the mud pit completely within pad fill azea. Assuming a pad fill slope of <br />2.5:1, natural slope of 40%, and a half acre drilling pad, placing the pit 11 ft to 12 ft from <br />the pad fill slope will provide a safety factor in excess of 1.3. <br />Fill material was assumed to be a loose, sandy silty loam with an internal friction angle of <br />29 degrees and a unit weight of 85-lbs/cu.ft. The in-situ material was assumed to be a <br />dense, sandy silt loam with an internal friction angle of 29 degrees and a unit weight of <br />117-lbs/cu.ft, The point of interest for this investigation was the possibility of either a toe <br />or base circle failure, both total failures of the bench integrity though they pose no threat <br />to life or property. The output of this analysis is depicted in the attached document. <br />Mud pits will not be used to assist in controlling run-off from the pads. If a mud pit <br />cannot be accommodated because of shallow soils due to sandstone outcrops, then a <br />pipeline will be constructed and the cuttings pumped to another proposed drill site's mud <br />pit. <br />Water for the drilling operations will be pumped to the drill sites from the North Fork of <br />the Gunnison using high-pressure hose. Alternatively, water may be transported to the <br />drill sites with mobile water carriers. Mountain Coal Company, L.L.C. owns water rights <br />for these water resources, MCC may place portable stock tanks near the drill sites and <br />maintain a minimum water level in the tanks to insure water is available for stock and <br />wildlife. This will reduce the risk of stock and wildlife approaching the mud pits for <br />water. <br />DRILLING ACTIVITIES <br />Drilling acfivities for the proposed methane drainage wells will include mobilizing drill <br />equipment to the sites and drilling and setting approximately 40 feet of 16-inch surface <br />casing into bedrock. The holes will be rotary drilled with a 12 '/<-inch diameter hole to <br />within 250 feet of the B-Seam, then cased with 9 5/8 inch ID steel casing. Then an 8 '/- <br />inch diameter hole will be drilled to within 120-150 feet of the B-Seam in the "relaxed <br />zone". The 8 '/<-inch diameter drill hole may be cased with a 7 5/8-inch slotted casing, <br />depending on the integrity of the hole, A depiction of a typical completed MDW is <br />attached as Figure No. 2, Typical MDW Well Design. <br />DE-GAS INSTALLATION <br />Passive de-gassing of the longwall panels would be accomplished by extending a non- <br />metal stack to the surface casing, attaching a lightning arrestor to it and venting to the <br />ambient atmosphere. Active de-gassing would require a trailer or skid mounted gas <br />exhauster, flame arrestor, valves, and non-metal stack with lightning arrestor that would <br />exhaust the gases to the ambient atmosphere. The trailer would be totally enclosed with <br />fencing and the fence gate locked to prevent public access to the equipment. The <br />equipment would need to be approved and inspected by the Mine Safety and Health <br />Administration (MSHA} prior to installation. <br />MONITORING <br />