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Purpose and Need Chapter 1 unforeseen mining or geologic circumstances, coal contract variability, etc. Ark Land's application for the Dry Fork LBA tract did not include foreseeable mining in the B Seam. However, the BLM has documented possible recoverable reserves in the B Seam. The coal lease, if it is issued, will encompass all coal within the 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 B Seam coal reserves represent about 14 months of additional coal reserves based on the rate of mining currently employed at the West Elk Mine. If the B Scam 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 of the FEIS. 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 certain levels 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 [he landscape for two 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 include, but is not limited to, 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. Table 1-1 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 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 iden[ifted at the leasing stage, due to the competitive nature of coal leasing and the fact that a 1-8 Dry Fork Lease-By-Application FEIS