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• When the coal is ripped rather than shot, large bulldozers with ripper attachments will <br />fragment the coal sufficiently for smooth ]oading operations. <br />Once the coal has been prepared for loading by either blasting or ripping, arubber-tired front- <br />end loader loads the coal into haulage trucks. Following loading, these haulage trucks <br />transport the coal along in pit roads to the primary crusher located just outside of the mining <br />area as shown on the Existing Structures -South Map (Map 22). <br />In order to visualize the overall mine plan, a range diagram was drawn. This diagram is found <br />as Mining Range Diagram (Map 24) and depicts operations by draglines in combination with <br />shovels and trucks. The past and anticipated annual production tonnage of coal is shown in <br />Table 3, Historic and Anticipated Annual Coal Production. <br />Coal to be mined at he Colowyo operation is present in at least 8 separate seams ranging in <br />thickness from 2 feet to 15 feet. The seams to be mined are designated from upper most to <br />lowest as Y (Y3 and Y2), X, A (Al, A2 and A3), B (Bi and B2), C, D (D1 and D2), E, and F. <br />To date, very little of the Y2, Y3 and A3 seams have been recoverable. <br />Coal from the mining area is transported to a coal crushing facility as shown on the Existing <br />Stmctures -South Map (Map 22). Details of the coal crushing and load-out facilities are <br />included in Section 2.05.3 under the heading of Mine Facilities. <br />After coal recovery by conventional truck/shovel and dragline methods has reached the <br />maximum economical recovery limit, Colowyo has the potential of using a highwall miner <br />when the conditions allow. The highwall miner can recovery additional reserves left in the <br />pit face that were deemed non-recoverable by conventional surface mining methods. This <br />new highwall miner technology can recovery coal up to 1600 feet in advance of the final pit <br />wall with an approximate coal recovery ratio of 40% to 60%. Once the coal has been <br />recovered and stockpiled in the pit, then the coal will be transported to the primary crusher <br />and train loadout by coal haul trucks. Refer to Map 23 for the location of potential highwall <br />mining areas. <br />As soon as possible after the coal is removed from the mining area and sufficient room is <br />available for back-filling, reclamation begins. In general, rough backfilling is completed by <br />the over- burden trucks and bulldozers since the operation has reached a "steady state, " as <br />shown on the Mining Range Diagram (Map 24). As stated earlier, overburden material <br />removed ahead of the operation is transported by truck around the active coal mining areas <br />and deposited into the mined-out areas. Either dragline may periodically be utilized on the <br />backfill material to assist in final spoil placement and in achievement of the planned final <br />topography. The final grade of the slopes will approximate the pre-mining <br />2.05-10 Revision Date: 9/19/05 <br />Revision No.: TR-60 <br />