2010-12-17_REVISION - C1981019 (108)

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R ULE 2 PERMITS approximately 7 bcy per ton. Normal bench dimensions and heights as described in the ground control plan will be used. Table 2.05.2 -3 presents the estimated yearly production. The Little Collom X pit is located approximately one and one -half mile north and 600 feet lower in elevation relative to the Collom Lite pit. Similar to the Collom Lite pit area, the area to be mined within the Little Collom X pit covers an area of two long ridge lines at about 7000 feet in elevation which is bisected by a 100 foot deep valley formed by the stream channel of Little Collom Gulch. Ultimately the Little Collom X pit will cover approximately 384 acres and will be 100 feet deep in places. Seams to be mined in the Little Collom X pit include the Y and X seams. As shown on the geologic cross - sections presented in Figure 2.04.6 and on Map 7, the coal seams to be mined are located in the axis of the Collom syncline with the northern portion of the pit having beds dipping approximately 3 to 10 degrees to the southwest re- orientating to flat in the axis hinge and then slightly dipping to the northeast in the southern portion of the pit. Mining will proceed as described on Map 2313, generally in a southward direction into the hillside along the bedding plane beneath the X coal seam. Coal production from the Little Collom X pit will take place in 2012 and continue through 2016. A total overburden /interburden volume of 56,383,261bank cubic yards (bcy) and coal tonnage of 6,383,000 tons estimated to be generated and produced, respectively, from the Little Collom X pit. For development of the Little Collom X and Collom Lite pits, Colowyo will utilize only truck/shovel techniques. Mining will be conducted in an up -dip direction (north to south) using conventional truck/shovel mining techniques. Once the overburden is sufficiently fragmented to allow for efficient removal and loading, overburden will be loaded and transported to the temporary out -of -pit spoil stockpile or to the adjoining mined -out pit. After removal of the overburden, the coal seams will be exposed. As the coal seams are exposed, they will be cleaned using auxiliary equipment, then either drilled and shot with explosives, or ripped to prepare the coal for loading and removal. When explosives are needed, the drilling will be performed by an auger drill. The drill hole pattern is generally spaced approximately 12 feet by 12 feet, though dependent upon the actual coal seam thickness. Drill holes will be loaded with either ANFO or a waterproof explosive (if the holes are wet), to a typical powder factor of about 0.2 pounds per ton. Once the coal has been prepared for loading by blasting or ripping, a rubber -tired front -end loader or excavator will load the coal into haulage trucks. Following loading, these haulage trucks will transport the coal along in pit haulage routes to the primary crusher located just outside of the pit, as shown on Map 25D (Collom Haul Roads). Coal from the primary crusher will be loaded into trucks and transported on a paved haulage road (See Map 25E — Collom Access Road, Sheets 1 -9) to the coal crushing and load -out facility at the Colowyo permit area as shown on the Structures and Facilities Map (Volume 8, Map 22). Details of the coal crushing and load -out facilities are included in Volume 1, Section 2.05.3 under the heading of Mine Facilities. As the temporary overburden stockpiles are constructed, best management practices to reduce sediment production and impacts to adjoining areas will be implemented. Interim reclamation of temporary spoil stockpiles will be performed to reduce resource impacts, if determined to be necessary. As soon as possible after the coal is removed from the mining area and sufficient room is available for back - filling, reclamation begins. In general, rough backfilling is completed by the overburden trucks and bulldozers. Final grading will be performed to recreate a post mining topographic expression that is Collom — Rule 2, Page 89 Revision Date: 1/23/09 Revision No.: PR -03