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Purpose and Need Chapter 1 lease boundaries. Therefore, although it is not anticipated that the B Seam reserves would be mined at this time, the RFMP includes a projection for eventually mining in the B Seam. The B Seam coal in the Dry Fork LBA may be mineable in the northwestern portion of the tract. Longwall panels would likely extend into these reserves from the northwest. The RFMP assumes the B Seam coal in the Dry Fork LBA tract would be mined between 2015 and 2016. The B Seam coal reserves represent about 14 months of additional coal reserves based on the rate of mining cuttently employed at the West Elk Mine. [f the B Seam were ever to be mined, it is presumed that it would be mined in a similar fashion to the E Seam, from the existing mine, and using existing facilities. The RFMP assumes a Longwall panel configuration that would cross Deep Creek and the Dry Fork of Minnesota Creek perpendicularly to obliquely. The RFMP was used to develop the coal mine subsidence prediction used to assess potential surface resource impacts. A detailed subsidence evaluation appears as Appendix B ofthe DEIS. 1.8.2 Reasonably Foreseeable Post- lease Surface Use In recent years, coal mines operating in the Somerset coal field have experienced build-up of methane gas in the underground workings after the rock strata have subsided due to mining (see Subsidence Evaluation, Appendix B). Under Mining, Safety and Health Administration regulations, mines are required to maintain methane 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 often used. For mining on existing leases north of the Dry Fork LBA tract, the West Elk Mine has used a system of MDWs to assist in liberating methane from the underground mine. These wells are drilled from the land surface into the mine workings and use an 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 yeazs 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 include 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 identified 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 (see Section 1.3 Leasing Process, Authorizing Acts and Relevant Policies, Plans and Programs). Table 1-1 Reasonably Foreseeable Surface Use Activity AIL 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 WeIIs For the purposes of this analysis, it is assumed that about 30 MDWs would be needed over the life of the lease, assuming about one acre of disturbance 1-8 Dry Fork Lease-By-Application DEIS