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Once the cutter head reaches the coal seam, the cutter head will be disassembled and removed from the A -leg <br />derrick. Using the same A -leg derrick, the excavated shaft(s) will then be lined to a nominal 2.5- or 4 -foot inside <br />diameter using a hydrostatic steel liner(s). The steel liner sections will be pre- fabricated off -site, hauled to the site <br />•and field welded in 30 -50 foot joints. The liner(s) will be floated into place. Once the liner(s) is in place, a <br />nominal 6- to 9 -inch thick grout seal will be pumped between the strata and liner(s). The grouted steel liner(s) will <br />serve to isolate the Twentymile Sandstone from the Wadge Overburden. <br />Upon completion of shaft drilling and steel liner installation for the shaft(s), the cuttings pit will be dewatered. <br />Excess water will be hauled to the Area 1 Pit, and the remainder will be allowed to evaporate. After dewatering the <br />cuttings pit and allowing the cuttings to consolidate and dry -out, the collection pit and cutting materials will be <br />covered with stockpiled materials from the shaft collar excavation, graded and revegetated with a temporary cover. <br />A sign(s) will be posted designating the temporary mine development waste pit. The cuttings and shaft collar <br />excavation materials will be utilized to re -fill the shafts during eventual reclamation of the shaft installation. <br />As shown on Map 23, additional entries will be driven from the 15 -Left gate -road to the south to connect with the <br />ventilation shaft(s). The entries will be driven in the same manner as used in TCC's development work, i.e. <br />continuous miners and shuttle cars. <br />Following commissioning, the shaft pad site and light -use road will be cleaned -up and surface areas graded and <br />stabilized by seeding with the temporary seed mixture. An 8.625 -inch (outside) diameter pipe will be connected to <br />the wall of the shaft liner for use as a rock -dust drop. The new 15LT Rock -Dust Installation will consist of a new <br />rock -dust tank, which will be mounted on four poured concrete piers; a connection to the rock -dust drop pipe; <br />required electrical and control equipment; and a dust collection system. A security fence with locked gate and <br />appropriate signage will be installed around the shaft opening to limit access to authorized personnel. <br />When these facilities are no longer needed to support ongoing or future mining and related operations, reclamation <br />will involve removal of surface structures and facilities, demolition of concrete foundations and pads, disposal of <br />•concrete debris in the shafts, replacement of cuttings from the temporary cuttings pit in the shaft, plugging and <br />sealing of the shaft in accordance with applicable State Engineer requirements, grading of disturbance areas to <br />blend with the surrounding terrain, soil material replacement, and reseeding with the permanent Rangeland <br />revegetation seed mixture. <br />• <br />TR11 -78 2.05-45.25 09/15/11 <br />