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VII. Effects of Proposed Action <br />Assumptions <br />For this analysis, all lease stipulations as described in section III are considered to be in effect. <br />Direct and Indirect Effects <br />The lease modification itself is an administrative action and carries no direct effects with it. It <br />does, however, authorize underground coal mining within the modification area, and that mining <br />may result in subsidence of surface topography as coal is removed from belowground. This <br />subsidence has resulted in landslides and other surface changes on unstable and steep slopes in <br />other portions of the Forest in which such mining has occurred. Such disturbance, however, has <br />been limited to steep and unstable ground and has not been widespread in undermined areas. <br />Most surface subsidence has been relatively uniform across the landscape and in most areas does <br />not visibly alter surface features or vegetation. <br />In a subsidence worst -case -scenario situation, this lease modification and the underground mining <br />associated with it would alter the entire surface topography of the modification area in such a <br />manner as to knock down all trees and reduce suitable lynx habitat to unsuitable conditions. The <br />area of impact would therefore include 1436 acres of lynx habitat, that being the portion of the <br />lease modification currently suitable. These values are based on the R2VEG GIS coverage for <br />this area, and may not reflect recent impacts to aspen stands due to SAD. <br />If no habitat is lost due to subsidence, which is the expected outcome, then the lease modification <br />and associated underground mining would have no effect on the habitat suitability at the surface <br />and there would be no effect to lynx as a result of the modification. <br />However, underground mining requires surface facilities for safety, specifically methane drainage <br />wells (MDWs), also known as Gob Vent Boreholes (GVBs). There is a Reasonably Foreseeable <br />Mine Plan which accompanied the request for lease modification, which at a gross level provides <br />information on surface activities associated with the underground mining within the lease <br />modification area, including the number of MDWs required in this area and the approximate <br />mileage of temporary roads required to access and construct these MDWs, as well as information <br />on the longevity and rehabilitation of surface disturbance.. This plan is described in the proposed <br />action above and is being analyzed concurrently. <br />The plan does not have specific locations for the MDWs and associated roads which comprise the <br />surface disturbance. It does, however, indicate the expected acreage of disturbance required to <br />operate the mine, approximately 75 total acres. Without knowing exactly where the MDWs and <br />Sunset Lease Modification Biological Assessment 12 <br />