2024-04-25_PERMIT FILE - C1982056A

Home Browse Search

Development of the WCR will involve construction of a rock-slope access from 5-North Mains down to the Wolf Creek Seam. Once the rock-slope reaches the Wolf Creek Seam, main entries will be driven to access Panels WC-7RT through 9RT, as shown on Map 23WC. The gate-roads for these panels will be extended approximately)1,000 to 12,500 feet to the east, and will be connected by bleeder entries in preparation for future longwall mining. The Mains will subsequently be extended to the south to access Panels WC-5RT through 6RT. Once the Mains are in place, gate-road and bleeder entries will be developed progressively for the longwall panels, as shown on Map 23WC. Areal Extent With adjustment of the eastern Permit Boundary to accommodate the planned WCR development and mining activities, the Permit Area will total approximately 22,647 acres, of which approximately 5,120 acres have been affected in the Southwestern and Eastern Mining Districts. Ongoing mining in the NMD has affected approximately 5,430 acres, mining in the WMD will affect approximately 3,150 acres, and mining of the WCR will result in approximately 124 acres of incremental subsidence, with a total affected acreage over the mine life of approximately 13,824 acres. Most of the planned Wolf Creek mining will not increase the overall affected area since it will fall within the existing affected area for the EMD and NMD, however, the eastern end of Panels WC- 5RT through 6RT will extend beyond the Wadge Seam mining limits. These areas contain all mineable coal reserves bordered by the 15 percent gradient cutoff line to the east and west and the property line to the south. At the conclusion of mining, approximately 65 percent of all the coal contained within the mineable reserve area will have been extracted (see Maps 7, 8, 9, 9a and Figure 1, Geologic Cross-Sections A-A' through E-E', and Exhibit 53). Mining Layout The underground mine layout was designed with the objectives of safety, rapid development, optimum access to outlying reserves and maximizing recovery. Numerous physical, geotechnical and operational variables influenced design of the mining layout. Mining activities are bounded on the east and west by lease boundaries, faults, or a 15 percent seam gradient cutoff limit, to the south by a lease boundary and mined-out reserves, and to the north by the a 15 percent seam gradient cutoff limit. Reserve access is by a network of main entries oriented primarily north-south and east-west. Longwall panels are laid-out in all areas where economically recoverable coal has been identified and wherever geologic conditions are compatible with safe and efficient mining operations. The following factors influenced the layout of the underground mine: Lease Boundaries -Limits the extent of mining extension Geotechnical Characteristics -Including rock and coal strengths,jointing, cleating and quality Structural Features -Major fault zones and steep gradients are avoided or crossed selectively Reserve Access-Minimal development and capital cost and optimum men and materials transport Orientation-Mains, sub-mains and panels are oriented to avoid directions that have the potential for instability Water-Inflow and control has been considered through sump location and up-dip development Subsidence-Controlled subsidence is planned over areas of full seam coal extraction Ventilation-Influences the size and number of mine openings. The general mine plan layout and timetable is shown on Map 23. Main entries consist of parallel openings, typically five, but may be increased or decreased in number depending upon conditions, driven on 80-foot centers. The openings are approximately 20 feet wide and separated by 60-foot pillars. Crosscuts are driven to connect the mains every 100 feet. Longwall panels are laid out in 500 to 1,000 foot wide by 3,000 to 20,000-foot long blocks. The blocks are bordered by a 2 or 3-entry system of gate-roads. A typical mine section layout is shown on Figure 7, Typical Mine Section. TRI 8-92 2.05-13.1 09/26/18