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Coal Metlrane Draieoge Project - Panek 16-24 West E!k Mine 2.3.8 Alternatives Eliminated from Further Study 2.3.8.1 Collect Methane Gas for Commercial Sale and Use 2-8 The USFS does not have the authority to require MCC to capture and sell the methane gas. As a leasable "mineral" resource on public lands, natural gas from the federal mineral estate is managed for leasing and production by the BLM. Under a valid oil and gas lease, beneficial use, including development, production, and commercial sale of gas would be allowed. At the present time, there are no valid existing oil and gas leases or pending lease applications for the project azea. MCC and other coal operators in the area are evaluating the potential for commercialization of the methane resource (refer to Section 2.5), however, evaluations are in a very preliminary stage and the timeline required for evaluation and pernvtting (if commercially viable) is not compatible with this project (refer to Section 1.2). MCC plans to continue commercial methane production as the currently proposed project progresses. The BLM is awaze of ongoing activities relative to methane drainage from azea mines and the need for additional methane drainage. The BLM is monitoring the situation on an ongoing basis. The BLM has stipulated (Coalbed Methane/Coal Mining Stipulation) that, within the Paonia-Somerset Known Recoverable Coal Resource Area (KRCRA), any oil and gas leasing and development be coordinated with affected coal operators. In addition, the stipulation precludes the BLM from approving any oil and gas operations that would compromise maximum economic recovery of the coal resource or the safety of underground mining operations. Practical constraints on commercial development of gas in this area include the depth of the resource, the occurrence of the resource, resource quality and quantity, and limitations relative to effective resource development and production. Initial estimates of gas production under a scenario where vertical drillholes would be used to pre-drain the coal in advance of mining indicate that less than 30 percent of the methane would be drained over afive-year time period and less than 40 percent would be drained over aten-year period using a 40 acre drillhole spacing (drillholes on a 1,320 foot grid) and assuming relatively high permeabilities and gas yields. A network of collection pipelines and storage tanks would be necessary to collect, store, and transport the methane and, since there is no gas transmission pipeline in the immediate area, the gas would have to be trucked from a central temporary storage point to either a pipeline transfer point or gas processing plant. 2.3.8.2 Reduce the Number of Drill Pads by Using Angle Drilling in Combination With Underground Horizontal Drilling Angle drilling allows multiple MDWs to be completed from a single drill pad on the surface. Limited angle drilling is proposed for this project in areas where topographic and other access constraints prevent drilling of vertical MDWs. The costs and risks associated with angle drilling are much greater than with vertical drilling, so vertical drilling is the most effective drilling method. The Proposed Action reflects MCC's best efforts to balance the risks of angle drilling with environmental constraints. 2.3.8.3 Reduce or Eliminate Methane Emissions by Flaring the Gas Total methane liberation from the West Elk Mine is currently 16.5 million cubic feet (mcf) per day. Throughout the proposed project, liberated methane is expected to vary between 12 and 20 mcf per day. Approximately half of the liberated methane would be vented through methane drainage wells. The remainder would be collected from horizontal wells and vented through the mine ventilation system. About 29 U.S. coal mining operations use vertical methane drainage wells to vent gas from the mines. In all cases, gas vented from these wells is discharged directly into the atmosphere. Under ideal EnvimnmenmlAsrecrment a:~wrinr...m. .weir voy~vgaer usFs ststoz m