2012-02-28_PERMIT FILE - C2009087A (4)

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RULE 2 - PERMITS rockdust to the underground mine through a 12.25 -inch cased borehole, approximately 250 feet deep. The borehole will carry a steel pipe for the rockdust drop, and a steel conduit to supply power for the tank feeder drive and top blower. The pad for each rockdust tank will consist of a solid one - foot thick footer and four concrete pillars containing approximately 22 cubic yards of concrete. The tank pads and associated truck access /unloading area will be surfaced with pit -run gravel to control runoff and erosion. Transfer Building and Coal Stockpile — Coal from the initial development mining will be conveyed from the mine portal to a transfer point and then to the coal stockpile area directly north of the portal area. A radial stacking conveyor will be used to create a coal storage pile. If needed, the excess coal will be truck- hauled to the southern coal storage area and stored until haulage to nearby customers can be continued. It is anticipated that initially no more than 400,000 tons will be stored between the two coal storage areas. After the initial development, coal will be conveyed from the mine portals by a 72 -inch covered conveyor through a drive building to the transfer building. The drive building and transfer building will be steel -frame buildings with steel sheathing 30 x 30 x 20 foot high and 40 x 40 x 30 foot high, respectively. The buildings will set on steel pylons driven to competent bedrock (approximately 40 feet in depth) and connected to a 12 -inch thick concrete slab floors. Building foundations and floors will contain approximately 93 cubic yards of concrete. The coal will be conveyed from the transfer building to the run of mine (ROM) stockpile, where selective placement in conical piles and two stack tubes will allow some blending to meet customer specifications. The ROM stockpile will provide approximately 300,000 tons of live storage using a combination of stack tubes and dozer push to control stockpile size and grade distribution. Current plans call for coal to be loaded from the ROM stockpile to highway trucks. Electrical Substation and Powerlines - The electrical substation will be located near the entrance to the mine face -up area Electric power will be provided by Yampa Valley Electric Association from an existing 69KV powerline that parallels RCR27. The substation will be approximately 105 x 150 feet, and will be enclosed by a security fence with locked gate to prevent unauthorized access. The substation will contain transformers, capacitors, switch gear and control equipment. An adjacent area will be disturbed to provide a buried grounding bed for the substation. From the substation, overhead lines will distribute power to the mine surface facilities at 4,160 volts, and supported cables will transfer power to the underground operations at 12,470 volts through four fl- inch cased power boreholes, approximately 250 feet deep. SCCC will construct required power distribution lines within existing road easements, where feasible to minimize disturbance. Where it is necessary to construct new lines outside existing road easements, SCCC does not intend to develop new roads for line construction or maintenance. Line construction equipment will minimize surface disturbance by driving overland to pole locations, with construction activities scheduled to take advantage of favorable ground conditions. In the event that surface disturbance is unavoidable, available soil materials will be windrowed to the side, prior to disturbance, with the soil being pulled back over the disturbed area and reseeded on completion of construction activities. Electrical Metering Station — The metering station will be located northwest of the portal area. The metering station will be a pole mounted disconnect and a system of meters , on a concrete pad 30 x 30 feet. The station will be enclosed in a security fence with a locked gate. TR- 01 -10. 2.05 -16 Revision 02/11