2007-06-29_PERMIT FILE - C1981022A (2)

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Snzion- 2.05.3 G Declines to the GSeam -Three declines, including the intake, bekline, and return • entries and the associated concrete, structural steel and corrugated metal face-up structures extend from the finished grade at the Sanbom Creek Mme portal area down to the GSeam The declines extend about 70 feet, in horizontal distance, from elevation 6,057 to 6,044. During 1995, an additional rock slope was developed from the Gseam to the surface. The rock slope extends about 200 feet in horizontal distance, from elevation 6,042 to 6,097 at the surface. D. Mine Ventilation Installation -Two mine ventilation fans, associated fan housings and steel duct work, drive motors, and control equipment are installed near the return decline. A twelve-foot deep concrete shaft connects the return decline ro the steel ductwork on the surface. A smaller fan was installed for the initial mine development in late 1991. A large fan was subsequently installed in 1993. The ventilation system is designed so either fan can be used to ventilate the mine to provide for a backup or supplemental ventilation capability. E. "C' Gulch Ventilation Shaft and Fan Installation - A ventilation shaft was constructed from the surface to a depth of approximately 450-feet to intercept the Sanbom Creek B Seam mine workings as a supplemental source of air to assure adequate ventilation flows as mine workings are extended to the east and north. A concrete slab on the surface is connected to the shaft collar, a grouted steel-plate liner extending to a depth of approximately 70 feet. The retnaittder of the shaft is supported by 6-foot resin bolts installed through wire mesh radially around the perimeter of the shaft with 3-inches of shotcrete over the wire mesh to provide a smooth shaft lining and reduce resistance to airflow. A ventilation fan has been installed on the GGulch Ventilation shaft to increase • ventilation airflow and pressures. The fan installation consists of a ventilation fan, steel fan housing and ductwork, drive motor, and fan controls mounted on a concrete slab foundation. Power is provided to the fan drive motor by a drop-line from a neazby transmission pole with direct power feed from the nearby Substation No. 3. Because the fan installation is close to old Highway 133, it is surrounded bya chain-link security fence with locked gate to limit public access. Temporary facilities including a hoist frame, hoist winches, shop, and water storage tank and pump, installed for shaft construction have been removed and associated disturbance areas reclaimed once shaft construction was completed. A short segment of light-use road approximately 100-feet in length provides access for inspection and maintenance. Soil material from the shaft disturbance area was recovered and stockpiled in the existing Substation No. 3 soil stockpile for future use in reclaiming the site. Soils aze relatively deep in this area and soik were salvaged to a depth of approximately4-feet, resulting in recovery of approximately 3,000 cubic yards of soil material. The shaft excavation material was placed underground in previously mined-out areas. F. Electrical Substation No. 2 - A fenced substation, located in the Sanbom Creek Mme portal azea, is designed to provide electrical power to the mine, ventilation fan, and overland conveyor. Primary power is supplied from aDelta-Montrose Electric overhead powerline. G. Electrical Substation No. 3 - A fenced substation is located approximately two miles east of the Sanbom Creek Mme portals along old State Highway 133. The substation is designed to provide electrical power to the mine through a borehole. Primarypower is supplied from aDelta-Montrose Electnc overhead power line. Degasification Boreholes -Gob vent boreholes have been or will be drilled from the surface to intercept the underground mine workings in order to bleed-off accumulations of methane gas and prevent potentially dangerous gas seepage from the sealed underground mine TR4R 2.05-19 Revised nctober 2004