Laserfiche WebLink
6.0 MAXIMUM ECONOMIC RECOVERY <br />^ The Deserado Mine is planned for a maximum economic recovery within the constraints of safety <br />and existing technology. Longwall mining has been planned to the greatest extent possible since <br />' this method allows virtually 100 percent extraction of the panels. Room-and-pillar mining is planned <br />for those areas where longwall mining is not practical. The pillars in these panels will also be <br />' partially extracted as long as it could safely be done. An overall extraction rate of 67 percent is <br />expected from the room-and-pillar panels. <br />' It has been stated that coal less than 4 feet in thickness or under less than 100 feet of overburden <br />is considered unmineable for the reason of safety and equipment constraints. <br />Plates 7 and 8 show a number of other azeas left unmined which would otherwise be mineable <br />under the thickness and overburden criteria. These areas are not mined for one or more of the <br />following reasons. <br />1. No mining in areas 100-feet from the 100-year flood plain. This boundary is shown in <br />t Section 11 of the mine plans. <br />N 2. No mining where the reject percentage is expected to exceed 50 percent unless it is <br />necessary for mine development. Such areas are marked in both the D and B Seam mine <br />plans. <br />3. No overlapping multiple seam mining because the interburden between D and B Seams is <br />' too thin. Such areas are shown in Section 33 of the D Seam mine plan and Sections 2, 4 <br />and 11 of the B Seam mine plan. <br />1 4. No room-and-pillar mining in D Seam if longwall mining is planned underneath in the B <br />Seam. Only longwall mining is planned in the D Seam if there is longwall mining planned <br />underneath in the B Seam. If longwall in the D Seam is not practical, or economically <br />feasible, or it jeopardized relatively better reserves in the B Seam, the area in question is <br />left unmined. <br />' 5. Geometric consVaint. Because of the difficulty encountered with prominent cleat, the mains <br />are not planned to be driven parallel to the lease boundary. This leaves a number of <br />' unmined Viangular areas near the lease boundary. <br />'• 34 <br />1 <br />