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State Req. <br />• As overburden is excavated from each cut, the dozers prepare <br />an advance digging bench on which to sit during the next <br />digging position. Following excavation of each cut, the dozer <br />will build switchbacks to the next digging position. These <br />switchbacks are necessary because the dragline cannot <br />efficiently walk on slopes greater than 8-13 percent such as <br />the existing mountainside slopes. As a result, all movements <br />of the dragline from one digging position to another, whether <br />uphill or downhill, are made through a series of switchbacks. <br />This procedure of removing overburden, scaling the highwall <br />and walking down the switchbacks continues until the dragline <br />reaches the coal recovery line. The dragline then deadheads <br />uphill to the cropline where a new pit is begun. <br />The proposed 770 deadhead routed are shown on Exhibit 12-1. <br />One of these routes will follow and be a part of the E5 and <br />E6 ramp roads that extend through regraded spoil behind the <br />• active pits. It is anticipated that this route will be <br />utilized in 1989. The E5 and E6 ramp roads as well as the <br />switchback between these ramps will be constructed as the <br />ramps are extended or the existing ramps will be widened to <br />accommodate the dragline. <br />The other deadhead route being proposed is located in the east <br />Wadge Extension Area. Since coal removal will occur closer to <br />the eastern coal lease boundary and, therefore at a lower <br />elevation, a new deadhead route below the mined pits is <br />necessary for the dragline to gain access to the top of tfie <br />pit. The new routes will be constructed similar to the <br />existing 770 deadhead route approved by the Division in Minor <br />Revision No. 27. Any topsoil will be first removed and the <br />proposed route constructed at grade as much as possible in <br />order to minimize the disturbance area. The dragline walking <br />surface will be constructed a minimum of 60 feet wide; <br />• however, the width could vary up to 100 feet to allow passage <br />of ancilliary equipment and at switchbacks. The grade will be <br />less than 15 percent with an average grade of 8-13 percent. <br />12-49 Revised 06/29/88 <br />