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` Description of the Operations and Reclamation Plan <br />Mining Method <br />Because the No. 7 coal of the Laramie Coal Group is close to the surface in <br />the Permit Area, Coors Energy Company decided that the most feasible method of <br />mining the coal would be by surface methods. Cost comparisons of several <br />surface mining methods were made and the use of draglines for overburden <br />removal was chosen for mining of this property. <br />Underground mining of this property was also considered, but the coal recovery <br />rate would decrease from 90+ percent recovery by surface methods to less than <br />50 percent recovery by underground methods. Also, the soft shales overlying <br />the coal seam would cave readily and the surface of the ground in the <br />mined-out areas would be pock marked with depressions caused by caving in the <br />mined out areas. The disrupted surface would not be desirable for its present <br />use as rangeland. <br />Mining Operations <br />Top-sand is removed to a depth of 72" and live handled to reclamation areas <br />and spread to a depth of 36". This practice was started in 1985 to recoup the <br />deficit of top-sand that had developed during 1981 through 1984, The deficit <br />developed because soils in the initial .mining area were poor. This material <br />is excavated with a bucket-wheel-excavator (B WE) and live handled to regraded <br />areas. A Marion 7500 Model dragline removes the remaining overburden in two <br />passes. The dragline then ramps down and strips to the coal using an extended <br />bench method. The exposed coal is then cleaned and loaded with the Demag <br />backhoe or Michigan front end loader. Blasting is only needed when infrequent <br />large boulders are encountered. <br />The coal is loaded into 85 ton rear dump haulers which carry the coal to the <br />truck dump or to the coal stock pile. Yearly coal production is expected to <br />be 350,000 to 400,000 tons for a total during the five year period of up to <br />2,000,000 tons. <br />Coal Processing, Storage and Loadout <br />After the coal is dumped by the haul trucks into the 150 ton coal hopper, the <br />coal is conveyed to and crushed by a Stampler Crusher-feeder to a 7 inch minus <br />product. A short belt conveyor then transports the coal to the secondary <br />crusher, An electromagnet removes any tramp iron from the coal while it is <br />being conveyed on the short belt. The secondary crusher further reduces the <br />coal to a fine consistency. <br />The coal is discharged from the secondary crusher onto a belt conveyor that <br />transports the coal to the top of the conical storage pile. Coal is dropped <br />through a la,~ering tube to the covered pile which has a storage capacity of <br />14,000 tons, The stored coal is fed by four vibrating feeders located at the <br />bottom of the coal storage pile onto a belt conveyor which transports the coal <br />to the loadout structure. No coal processing waste is produced by this <br />operation. <br />-5- <br />