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New Elk Mine C1981012 MT6 updates 3 January 18, 2013 <br />#16: NECC questioned the volume of topsoil to be replaced on the RDA. The permit describes the approved <br />surface disturbance area boundary as shown on Map 11 sheet 3 (green line). Using the surface disturbance <br />area as the area to cover (adjusting on the east side for the approved Refuse limit) and the configuration of <br />the completed RDA, the mean digitized approved disturbance area at the RDA is 28 acres. 28 acres times <br />0.75 ft. topsoil = 33,880 Icy, or 30,115 CCY Earth -Dry packed. Task 76a represents the approved RDA <br />disturbance area. Permit pages 2.05 -27 to 39, and Figure 6 (p. 2.05 -30) Show that the Division has <br />approved construction of the entire RDA up to 8000 feet elevation. Therefore the Division is required to <br />include tasks for the final configuration of the RDA. <br />Compaction of any remaining waste material left at the mine and brought on to the RDA would need to be <br />compacted prior to cover placement on the RDA. Assume the final surface would need compaction. Lifts <br />are 2 ft. thick. Based on Map 17, 8.13 acres would need final compaction. This is Task 76b. <br />The topsoil required for the south facing benches and face of the RDA were calculated as a separate task. <br />Task 077. Digitized face (benches) of the RDA as shown on Map 11 sheet 3 = 5.5 acres X 0.75 ft. thick <br />=6659 Icy. Using "Earth -dry packed" material =5919 CCY. Task 077 was recalculated using this corrected <br />topsoil volume. Topsoil would be hauled up RDA haul road to face. Taken as far down as safe, then pushed <br />with dump area dozer to the appropriate location. <br />#17: The Division concurs that the RDA haul road is approved to remain as a permanent road as per map <br />11. Task 79 has been eliminated. <br />#18: Task 082 had been included to place topsoil at the subsoil stockpile footprint. The current subsoil <br />stockpile is located south of the Purgatoire River in an area denoted on Map 15 as DR. This area had <br />previously been reclaimed. Topsoil was windrowed to the north side of the pad prior to re- disturbance. <br />Upon reclamation the topsoil would be pushed back. Task 082 has been recalculated using this <br />information. <br />#19: NECC questions the Division's use of 50% failure rate on revegetated areas. The Division did not <br />succeed in contacting the local extension agent in the Purgatoire valley, however, consultation with the <br />USDA -NRCS Web soil survey found that seedling mortality was listed as moderate on soils in the valley <br />bottom due to water availability, and low seedling mortality on the slopes. Based upon this information <br />from the Web Soil survey and the amount of disturbance of these various land types, the Division would <br />agree to reduce the seeding failure rate to 33 %. This failure rate will be applied to tasks 085, 086, 087, 088, <br />134, 153, 161, 165. <br />#20: The Division concurs that Warehouse 2, warehouse 2 pad Warehouse 3, hoist house and pad were <br />approved for bond release in SL2. These tasks have been removed from task 095. <br />The hoist house costs still included in task 095 are different dimensions than that released in SL2, <br />and are still pertinent to the current operations. <br />Building gutting costs have been removed from Task 095 since we believe this task is covered by <br />the building demolition cost. <br />