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would be beneficial to discuss highwall and low wall stability. <br />• 'Ile highwall is benched to reduce the potential for worker injury <br />due to highwall spalling. ZSr_ miners refer to the racks that are <br />dislodged frcxtt the highwall and fall to the floor of the cut as <br />"widow makers." 'Ile significance of the low wall is that it <br />demonstrates that a barrier is kept at the toe of the fill to <br />provide stability to the fill. lhis barrier will vary in width <br />depending on the extent of oxidized coal. It is anticipated that <br />the barrier, at a m,nimim,, will be ten feet in width. 247is in <br />oanbination with the dip of the coal bed will provide for a stable <br />fill. <br />Table V-1 identifies the areas to be mined and puts forth <br />the development schedule for those areas. Until the permit <br />application is approved TBhI is restricted to m;n;nq in Section <br />• 22 pursuant to the sequencing approved in Permit DhanUer 79-53. 'IYie <br />m;n;nq will continue to the west in Section 22, progressing <br />from cuts 2 through 9 in pit 2. At this time it is not expected <br />that further m;n;nq will occur i.Il the southeast quarter of Section <br />22 due to coal quality problans. <br />Overburden removal inwlves the use of the following <br />equipment: dozers, front end loaders, haul trucks, and an overburden <br />drill. ~e dozers remove the less competent material by pushing <br />it into the adjacent excavated cut. ?4hen more cca~~etent sand- <br />stones are encountered the overburden drill is used to drill into <br />the strata, a typical drilling and blasting pattErn is presented in <br />Figure V-1. ice the strata is drilled the holes are loaded <br />with explosives and the shot is fired resulting in the fracturing <br />V-13 <br />