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Areal Extent <br />The permit area of the underground mine, totals approximately 22,450 acres, of which approximately 5,180 <br />• - -- - - <br />acres have been affected in the Southwestern and Eastern 1VIining Districts. Ongoing mining in the NMIS will <br />affect approximately 5,580 acres, and future mining in the WMD will affect approximately 3,620 acres, <br />resulting in a total affected acreage over the mine life of approximately 14,900 acres (includes 520 acres of <br />surface disturbance outside mining areas). These areas contain all mineable coal reserves bordered by the 15 <br />percent gradient cutoff line to the east and west and the property line to the south. At the conclusion of mining, <br />approximately 65 percent of all the coal contained within the mineable reserve area will have been extracted <br />(see Maps 7, 8, 9, 9a and Figure 1, Geologic Cross - Sections A -A' through E -E'). <br />Mining Lavout <br />The underground mine layout was designed with the objectives of safety, rapid development, optimum access to <br />outlying reserves and maximizing recovery. Numerous physical, geotechnical and operational variables <br />influenced design of the mining layout. <br />Mining activities are bounded on the east and west by lease boundaries, faults, or a 15 percent seam gradient <br />cutoff limit, to the south by a lease boundary and mined -out reserves, and to the north by the a 15 percent seam <br />gradient cutoff limit. Reserve access is by a network of main entries oriented primarily north -south and east - <br />west. Longwall panels are laid -out in all areas where economically recoverable coal has been identified and <br />wherever geologic conditions are compatible with safe and efficient mining operations. <br />The following factors influenced the layout of the underground mine: <br />Lease Boundaries - Limits the extent of mining extension <br />Geotechnical Characteristics - Including rock and coal strengths, jointing, cleating and quality <br />• Structural Features - Major fault zones and steep gradients are avoided or crossed selectively <br />Reserve Access - Minimal development and capital cost and optimum men and materials transport <br />Orientation - Mains, sub -mains and panels are oriented to avoid directions that have the potential for <br />instability <br />Water - Inflow and control has been considered through sump location and up -dip development <br />Subsidence - Controlled subsidence is planned over areas of full seam coal extraction <br />Ventilation - Influences the size and number of mine openings. <br />• <br />The general mine plan layout and timetable is shown on Map 23. Main entries consist of parallel openings, <br />typically five, but may be increased or decreased in number depending upon conditions, driven on 80 -foot <br />centers. The openings are approximately 20 feet wide and separated by 60 -foot pillars. Crosscuts are driven to <br />connect the mains every 100 feet. Longwall panels are laid out in 500 to 1,000 foot wide by 3,000 to 20,000 - <br />foot long blocks. The blocks are bordered by a 2 or 3 -entry system of gate- roads. A typical mine section layout <br />is shown on Figure 7, Typical Mine Section. <br />Map 23, Mine Plan, represents a general overview of the planned mine layout. The locations and orientation of <br />mains, sub - mains, and panels is subject to change (within the limits of the planned mining blocks) as <br />development progresses, mining conditions change, new technology becomes available, or the land or <br />permitting status changes. In the event conditions (either general or in specific mine areas) are .found to <br />preclude effective longwall mining, TCC would utilize continuous mining methods in a manner to achieve the <br />best recovery possible under the circumstances. Every effort will be made, however, to maximize recovery of <br />those reserves compatible with extraction by longwall mining methods. TCC does not plan to conduct <br />underground coal mining operations within the Fish Creek Tipple permit area. <br />MR10 -251 2.05 -13.1 01/07/11 <br />