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Summary levels at or below about one percent to ensure worker safety underground. Typically, the mine ventilation system cannot effectively keep methane levels within safe working range, therefore additional methane liberation methods are oftentimes used. For mining on existing leases north of the Dry Fork LBA Tract, the West Elk Mine has used a system of methane drainage wells to assist in liberating methane from the underground mine. These wells are drilled from the land surface into the mine workings and use agas-powered exhausting pump to pull gas from the mine. Drilling these methane drainage wells requires construction of drill pads and temporary roads on the land surface. These features are on the landscape for [wo to six years, after which they are decommissioned and the land surface is reclaimed and returned to pre-mining land uses. Reclamation includes returning land surface to approximate original contour and revegetating. Reclamation has been generally successful within two to five years after reclamation work is completed. For the Dry Fork LBA tract, it is anticipated that methane drainage wells may be needed. Other post- leasing surface disturbance that could be reasonably anticipated includes exploration drilling, seismic exploration, groundwater monitor well installation, ventilation and escapeway facilities, water handling facilities, subsidence and hydrology monitoring facilities, and access roads needed for these facilities (MCC 2003). Estimated acres by alternative are shown in Table 1-1. For the purposes of the effects analyses in this EIS, it is assumed that surface disturbance would occur periodically over the life of the lease (expected to be about 25 years from lease issuance to lease relinquishment and final bond release). Site- specific locations of anticipated disturbance cannot be identiSed at the leasing stage, due to the competitive nature of coal leasing and the fact that a final mine operations plan has not been approved. For the purposes of this analysis, it is assumed that about 30 methane drainage wells would be needed over the life of the lease, assuming about one acre of disturbance per pad. Associated temporary road building acres assume a 30-foot average disturbance width for a temporary road with a 14-foot running surface. It is assumed that any exploration drilling and groundwater monitoring drill pads and access road constmction would utilize the same locations as those used for methane drainage wells. Subsidence and hydrology monitoring may require placement of monitoring devices on the land surface. These may include small subsidence monument, survey markers, stream gages, flumes, etc. Access to the facilities may require motorized vehicles that would use [he system of existing roads. One additional mine ventilation facility (i.e., shaft) may be needed during the life of the lease and would include associated road construction. At the leasing stage, it is not possible to locate site- specific areas where potential post-lease surface uses may occur; therefore, the surface use and disturbance estimations will be used to aid the effects analysis and cumulative impact analysis discussed in each resource section in Chapter 3. If surface uses are proposed during the life of the lease (if it is issued), then the site-specific proposals would be made based on surface use stipulations on the lease and NEPA analysis completed at that time. Table S-1 Reasonably Foreseeable Surface Use Activity Alt. B Alt. C MDW (number of) 30 22 MDW (acres) 30 22 Miles of temporary roads for MDW 4.4 2.9 Temporary roads for MDW access (acres) 16 11 Acres for ventilation (acres) 5 5 Access for ventilation (acres) 3.5 3.5 Total rounded acres 60 43 MDW =Methane drainage wells Desigu Features of the Proposed Action The Proposed Action includes conditions for protection of non-coal resources in the form of lease stipulations derived from restrictions developed from application of the Coal Unsuitability Criteria S-4 Dry Fork Lease-By-Application DEIS