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Currently, a Bucyrus-Erie 1300W dragline and a Marion 8050 dragline are <br />used for overburden removal over the lower coal seams; a third dragline, <br />a Bucyrus-Erie BoOW, is sometimes used to supplement the capacity of the <br />BE 1300W or Marion 8050 machines in the multi-seam scenario, and by <br />itself in single seam operations. <br />The generalized multi-seam dragline sequence at the Colowyo operation is <br />as follows: <br />The Bucyrus-Erie 1300W and Marion 8050 draglines begin the <br />sequence removing the overburden over the "B", "C", and "D" <br />seams in a single sidecast mode, spoiling the overburden into <br />the previously mined-out pit. The "E", and "F" overburden is <br />removed from the spoil side of the pit. The spoil from the <br />benching operation will be placed to allow the draglines <br />sufficient room and adequate reach to remove overburden while <br />operating on the spoil side. The draglines construct <br />temporary ramps in order to walk to the spoil side. <br />The "B" overburden is first drilled and blasted, removed by <br />the draglines, "B" coal is removed behind the advance of the <br />draglines, then the drilling is initiated on the overburden of <br />the "C" seam. This sequence is typical through the "F" seam. <br />Upon complete removal of the overburden over the "F" seam, the <br />draglines walk around the end of the pit to the next cut to <br />begin removal of the overburden over "B" coal seam. <br />~J <br />2.05-7 <br />Revision Rp'7, fd~f- 9 ~ 2 <br />Revision No. `f L <br />