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re-compaction of surface materials, placement of geotextile. in selected areas, and placement and compaction of approximately 8" of pit-run gravel and 3" of road-base material. The access road surface will be approximately 24' wide and will be graded and crowned to promote effective drainage. Road construction requires minimal cut and limited fill. Fill slopes will be graded to a 3H:1V and stabilized by seeding with the ( topsoil stockpile stabilization seed mixture. Preparation of the ventilation shaft pad involves topsoil recovery and stockpiling, installation of required drainage structures, grading and compaction to establish a level pad working area, excavation of a collection pit for blind drilling of the shaft pilot hole and shaft, stockpiling of the excavated material, and placement of gravel surfacing material to control dust and sediment from the pad area. The collection pit will be approximately 100' x 200' x 10' deep and is sized to contain all drilling fluids. In the event unanticipated ground water flow into the boring is encountered then the pits may be enlarged or additional pits excavated to handle the flow. Prior to the beginning of the blind drilling process, an extensive pressurized pre-grout operation utilizing small diameter holes around the shaft perimeter will be considered and undertaken "as needed to limit groundwater flows between "the shaft and the formations. If needed and once the pre-grout operation is completed, a surface casing will be excavated to an approximate 10' diameter and set to competent rock at a depth of approximately 10-15 feet. The surface casing will be finished to an approximate 8' inside diameter and will be large enough to accept the casing and drilling tools. This surface casing will be either steel casing grouted in place or cast-in-place concrete. A 48' by 24' concrete T-shaped pad will then be poured to accommodate the drilling and casing equipment. Specialized blind drilling equipment in the form of an A-leg derrick will be used to drill the pilot hole and excavate the shaft. A nominal 17-1/2" pilot hole will then be drilled to an approximate depth of 1000' and ~/ surveyed to determine vertical shaft deviation and location underground for mine entry cut-ins. The pilot hole will then be reamed to a nominal diameter of 7.5' to accommodate the final steel liner. The reaming technique utilizes an inverted disc cutter equipped hemispherical raise bore head to cut the rock. During the drilling of the pilot hole and the 7.5' diameter excavation, all cuttings will be removed from the excavation using an airlift system with water (reverse circulation) being the circulation media. The cuttings will be placed in a 200' x 100' x 10' deep, watertight cuttings pit that has been constructed on the shaft pad adjacent to the shaft excavation. The cuttings pit will be lined with a nominal 30-mil PVC flexible membrane liner having a permeability of ~10-12 cm/sec. The cutting head is rotated from the surface by the drill pipe, which also serves as a conduit to transfer cuttings from the shaft bottom to the surface collection pit. The drill pipe also serves to suspend the drilling assembly in the hole and is tensioned to adjust the cutting weight on the head and to keep the drill pipe straight.- The cutting head moves the water from near the center of the head and discharges it at the periphery of the head. This water then flows down around the cutters and washes the cuttings towards. the pick-up pipe in the center of the head. The drill pipe's upward flow is activated by compressed air injected down the center of the drill pipe. Rock cuttings are moved by the circulation of the water down the hole, across the shaft bottom and up the drill pipe to the surface collection pit. Within the collection pit, the rock cuttings are separated or settled out and the water is allowed to drain back or is pumped back into the hole-for re-use. The cuttings volume will be approximately 1,650 YD3 (2,475 YD3 swelled by 50%). Upon completion of the shaft excavation and steel liner installation, the cuttings pit will be '~ dewatered. All water will be hauled to the Pit No. 2 located south of TCC's overland conveyor. The collection pit and excavated materials will then be covered with earthen materials, graded and revegetated. A sign(s) will be posted designating the shaft cutting