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development waste pit excavated within the shaft pad adjacent to the shaft excavation as shown on Map 1W. The cuttings pit will be lined with a nominal 30-mil PVC flexible membrane liner having a permeability of~10-" 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 neaz the center of the head and dischazges 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 upwazd 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 aze sepazated 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 CY (2,475 CY when swelled by 50 percent). Upon completion of the shaft excavation and steel liner installation, the cuttings pit will be dewatered. All water will be hauled to the old pit to the south of TCC's overland conveyor. The collection pit and cutting materials will then be covered with previously placed materials from the shaft collaz excavation, graded and revegetated with a temporary cover. A sign(s) will be posted designating the temporary mine development waste pit. The cuttings and shaft collaz excavation materials will be utilized to re-fill the shaft during eventual reclamafion of the facility. Once the cutter head reaches the coal seam, the cutter head will be disassembled and removed from the A- leg derrick. Using the same A-leg derrick, the excavated shaft will then be lined to a nominal 6' inside • diameter using a hydrostatic steel liner. The steel liners will be pre-fabricated off site, hauled to the site and field welded in 40' joints. The liner will be floated into place. This is accomplished by securing a steel bulkhead to the bottom joint and leaving the excavated hole full of water while the liner is being lowered into place. By calculating the exact buoyancy of the liner, and adding water to the inside diameter as needed, the liner is easily and safely lowered into position. Once the liner is in place, a nominal 9" thick grout seal will be pumped between the strata and liner to hold it in place. The grouted steel liner will serve to isolate the Twentymile Sandstone from the Wadge Overburden. As noted above, it is planned to pressure grout the Twentymile Sandstone to prevent seepage from it into the shaft. This will further assure that after final closure the water in this unit will be confined and not seep down on the inside of the shaft. Following completion of shaft boring and casing operations and removal of equipment from the site, the emergency hoist equipment will be erected on either the previously constructed or a new concrete pad. Average pad thickness will be 1-2 feet and total pad surface area will be approximately 800 sf. A fence will be constructed to enclose the surface collaz and emergency hoist installation. Following commissioning, the shaft pad site and access road will be cleaned-up and surface areas graded and dressed. In order to minimize potential environmental and aesthetic impacts associated with the 18-Right ventilation shaft and emergency hoist installation, surface drainage at the shaft site will be handled by two (2) up-gradient diversion ditches, two (2) down-gradient drainage ditches, the use of 20-inch diameter sediment logs around the lower portion of the topsoil stockpile, the use of Curlex single net (Curlex I) erosion control blankets over seeded cut and fill slopes, the combination of a rock filter (2-ft rock berm) and grass filter, and gravel surfacing under an SAE (Refer to Exhibit 8T for SAE detail). Drainage from . the other topsoil stockpiles will be addressed by upslope diversion ditches to route upgradient nmon around the piles, silt fence or wattles at the downslope toe of the piles, and rock check dams where the upslope drainage meets the designed road ditches. The limited road drainage will be handled by a MROS-194 2.05-45.6 07/2/05