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2 to have gas pressures at 500 pounds per square inch. In order to achieve 500 pounds per square inch, the existing gas pressures at the MDWs would require three-stage compression to achieve the needed compression. In addition, pipelines would be needed to convey gas to treatment and compression facilities. Economic Considerations There are additional uncertainties regarding whether the volumes of methane being vented would warrant installation of compressors, gathering and transmission pipelines, and a gas treatment plant, since volumes vary so much with the mine operation, and are almost totally dependent upon the mine air circulation system. There are also issues related to permitting these facilities so not to interfere with mine operations. BLM also researched using coal mine vent gas for electrical generation. There are numerous websites which show it being done, however none of them include any gas volume numbers or equipment requirement on which to base any analysis. No co-generation of electricity of data exists (gas quality needed, gas volumes, or equipment requirements) for coal mines as this is generally done specifically by electric companies. Further, a consultant to EPA's Coal Mine Methane Outreach Program acknowledged that capture and use of methane from the West Elk Mine is complicated by the distance to an existing natural gas pipeline (over 10 miles), suggesting that the quantity of gas potentially available may not warrant the investment in a pipeline. It was also brought forward that using to coal mine methane for electrical cogeneration is generally not used in the USA because electricity is available at low wholesale rates. Additionally, it was acknowledged that feasibility of capture and use is uncertain based on issues of variability in quantity and quantity of gas (personal communication Mike Cote July 18, 2007). If able to be put to beneficial use, the estimated amount of gas that may be released from the E Seam could heat approximately 34,800 to 39,500 homes (assuming a yearly output) based on EPA's methane converter, but does not include efficiency of homes.` Given the above circumstances, the general speculative nature and legal uncertainties regarding capture and use of the coal mine natural gas do not provide enough detailed information to effectively meaningfully disclose effects of an alternative that would consider such. Therefore, this alternative is not analyzed in detail. Methane Drainage Wells only on Currently Leased Coal Areas Public comment requested that the project be limited to areas within existing federal coal leases. It was mentioned that a decision to allow the methane drainage wells in currently unleased areas would serve to improve the prospects of leasing and developing unleased federal land. This alternative was not considered in detail because, with the sale of the Dry Fork Lease (analyzed in 2004-2005 in an EIS) effective date March 1, 2007, all lands in the project area have been leased. Use Horizontal Boreholes or Longhole Horizontal Boreholes Mine Ventilation Plans including design of ventilation system are approved by MSHA from submittals and measurements made by MCC. MCC has analyzed the use of directional drilling to achieve degasification goals from sites outside the IRA and has noted the following: s The number of homes referenced here is taken from EPA's comment letter on the Draft EIS. After consultation with EPA and MSHA, its was acknowledged that gas emission data used by EPA to make this estimate is a very coarse measurement, and that more refined emission data received from BLM is the best available data to use in the EIS analysis (See Chapter 3-Air Quality). 46 Deer Creek Ventilation Shaft and E Seam Methane Drainage Wells FEIS