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I, should be located so that barriers or boundaries, particulazly in low cover azeas, aze not under or <br />within the angle of draw or influence to sensitive renewable resource lands or existing occupied <br />residential dwellings. <br />Preventative Measures - 2.05.6 (6)Ifl(iii) <br />State-of--the-art longwall mining technology will continue to be utilized for extraction of the B- <br />Seam and for the extraction of the E-Seam in the permit azea. Although longwall mining may <br />initially induce more caving and fracturing of the roof rocks, as compared to the room-and-pillar <br />method, it offers the advantages of maximizing resource recovery; more complete subsidence; <br />equilibrium conditions occurring in a shorter period of time; (more uniform and predictable <br />parameters necessary for the evaluation of probable hydrologic consequences; and in general, fewer <br />and less significant adverse hydrologic impacts than room-and-pillar mining. <br />Anticipated Effects -2.05.6 (6)(~(iii)(A) <br />Long-term impacts on the surface aze predicted to be minimal above the longwall panels. The few <br />surface cracks over the mining panels that may occur aze expected to close once the longwall face <br />moves past the surface azea of influence. Surface cracks present above the chain or barrier pillars or <br />mine boundaries may remain open where permanent tensile strains remain after mining is <br />completed. However, at least several hundred feet of unfractured 'rock will typically exist between <br />any mine-induced surface fractures and the upper part of any mine-induced fractures above the <br />• caved zone in the mining panels. Therefore, from a pracfical standpoint, no interconnection <br />between the surface fractures and the mine workings is anticipated. Again, under a worst case <br />scenario, if a surface fracture were to occur concurrently within an area controlled by faults or <br />bedrock lineaments, there could be interconnection between adjacent sandstones. However, even <br />under these conditions, the fractures would most likely not extend through the ductile claystones. <br />Reduction Measures (Underground) - 2.05.6 (6)(fl(iii)(B)~(I--III) <br />Underground measures that may be taken to reduce surface strains above the chain pillars could <br />include, but are not limited to; (1) designing the pillars to yield and crush after mining (thus <br />minimizing humps in the subsidence profile), (2) planning a rapid and uniform mining rate. Any <br />plans to reduce chain pillaz dimensions to reduce subsidence impacts must, of course, be <br />balanced with health and safety conditions in the mine. Plans for a rapid and uniform mining <br />rate aze affected by market demands for constant, high volumes'of coal as well as unsafe mining <br />conditions, such as accumulations of methane, but will be implemented if at all possible, under <br />areas that are particularly sensitive to surface cracking, such as perennial stream channels. <br />Preventative Measures (Surface) - 2.05.6 (6)(~(iii)(C)(I-V) <br />Surface measures that may be taken to reduce or prevent damage to applicable structures or water <br />resources could include, but aze not limited to; (1) engineering, design, and construction of <br />structures to withstand varying ground stresses, (2) re-locating structures or ponds to mid-panel or <br />• outside the angle of mining influence, and/or (3) enhancing or reinforcing water resource production <br />or de]ivery systems (e.g., pipeline), respectively. <br />2.05-136 Masch 2005PR11 <br />~ Irk D~ <br />