2010-04-15_PERMIT FILE - C1994082 (5)

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• equipment. The type and numbers of reclamation equipment are dependent on a number of factors, including quality and quantity of spoil material to be graded, distances spoil must be moved, projected postmine contour configuration, and weather conditions. Type and size of the coal processing facility are based upon the quality and quantity of coal produced, the type of processing required, and the transportation facilities available to handle the finished product. Service facilities such as shops, office buildings, warehouses, bathhouses, powder storage, electrical supply lines, and water lines that may be constructed are designed to be in conformance with all applicable State and Federal safety regulations. l-able 12-1 lists the major equipment currently in use or that has been used at Yoast. With the coal reserves defined and equipment chosen, it becomes the engineer's task to apply his technical expertise to the design of a facilities site plan, mining plan, ground control plan, haulage road system, surface water control plan, sediment control plan, power distribution system, postmine contour configuration, and a variety of inter-related projects. The processing and support facilities are generally located at a site near the center of the reserves in order to balance haulage distances. Factors such as topographic relief, strength of foundation materials, adequacy of drainage and accessibility are normally considered in the engineering design. The design of a mining plan is governed by several factors, including economic considerations, drainage patterns, relief, slope, and • geologic structures. Normal pit progression would begin at a "cropline" (outcropping) or shallow area and progress toward the deeper coal. The advantage of this technique is a lower production cost in early years. However, the cost of production becomes progressively higher as the pits advance. At Yoast, the geologic structure prevents this normal progression and pits must be oriented somewhat perpendicular to the cropline. By removing the overburden from cropline to recovery line in the same pit, the cost of production is more constant over the life of the mine. The best techniques for orientation of pits with respect to drainage patterns are to lay out a sequence of pits where the natural drainage is away from or parallel to the pits. The techniques used at Yoast to deal with the relatively high relief, slopes, and geologic structure will discussed in the following section. A haulage road system is designed with roads of appropriate width and grade to accommodate the intended traffic. In mountainous terrain such as that found at Yoast, the construction of switchbacks is sometimes necessary to maintain the flatest possible grade and minimize the area of disturbance. Safety berms will be utilized where required by steep side slopes. Surface water control plans normally utilize ditches for overland diversion of surface water as well as pit sumps for C PR-02 3 Revised 03/05