2018-07-09_PERMIT FILE - C1981019A (24)

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RULE 2 PERMITS Electrical Conductivity Greater than 12 millimhos/cm Sodium Absorption Ratio Greater than 15 The laboratory results are kept at the mine site. Results of the sampling program are provided in the appropriate Annual Reclamation Report and are periodically checked during DRMS quarterly complete inspections. If the results of the sampling indicate that one or more of the parameter suspect levels is reached, the Division will be contacted. At that point, Colowyo, will resample the area to determine the extent of the suspect material. If the problem area is greater than one acre in size, it will be necessary to cover the area with at least five feet of acceptable material before the application of topsoil. After removal of the overburden, the coal seams are exposed. As the coal seams are exposed, they are 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 is performed by an auger drill. The drilling pattern is in the range of 12 feet by 12 feet, but is dependent upon the actual coal seam thickness. Drill holes are loaded with either ANFO or a waterproof explosive. When the coal is ripped rather than shot, large bulldozers with ripper attachments will fragment the coal sufficiently for smooth loading operations. Once the coal has been prepared for loading by either blasting or ripping, a rubber -tired front-end loader loads the coal into haulage trucks. Following loading, these haulage trucks transport the coal along in pit roads to the primary crusher located just outside of the mining area as shown on the Existing Structures - South Map (Map 22). In order to visualize the overall mine plan, a range diagram was drawn. This diagram is found as Mining Range Diagram (Map 24) and depicts operations by draglines in combination with shovels and trucks. The past and anticipated annual production tonnage of coal is shown in Table 2.05-2, Historic and Anticipated Annual Coal Production. Coal to be mined at he Colowyo operation is present in at least 8 separate seams ranging in thickness from 2 feet to 15 feet. The seams to be mined are designated from upper most to lowest as Y (Y3 and Y2), X, A (Al, A2 and A3), B (B1 and 132), C, D (Dl and 132), E, and F. To date, very little of the Y2, Y3 and A3 seams have been recoverable. Coal from the mining area is transported to a coal crushing facility as shown on the Existing Structures - South Map (Map 22). Details of the coal crushing and load -out facilities are included in Section 2.05.3 under the heading of Mine Facilities. After coal recovery by conventional truck/shovel and dragline methods has reached the maximum economical recovery limit, Colowyo has the potential of using a highwall miner when the conditions allow. The highwall miner can recovery additional reserves left in the pit face that were Rule 2 Permits 2.05-4 Revision Date: 5/25/18 Revision No.: RN -07