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forming material. Mitigation of any unsuitable zones within the underburden material <br />will be by avoidance, as these zones will not be disturbed by mining activities. <br />Typical weathered and unweathered overburden and the interburden handling operations <br />are described in Section 2.04.6, Geology Description, Section 2.05.3, Operation Plan and <br />Section 2.05.4(2)(c), Backfilling and Grading. The suitable weathered overburden (upper <br />most strata) is typically comprised of unconsolidated material and will be mined in a <br />single bench and hauled around the pit ends and placed on top of the unweathered <br />overburden and interburden material which has been cast blasted and dozer pushed or <br />excavated by truck and shovel from the highwall across the pit to the regraded spoil area. <br />During the preparation of the initial boxcut area, the existing topsoil materials will be <br />salvaged in a single lift, using a combination of equipment including dozers, shovels and <br />loaders, whereupon it will be loaded onto haul trucks which will transport the salvaged <br />topsoil to a designated topsoil stockpile. However, as the mining operations advance and <br />there is sufficient regraded spoil behind the pit for reclamation, topsoil will be direct <br />hauled from the mine area to the regraded area. A loop road around the pit is used for this <br />operation. In some cases, the topsoil is temporarily pushed in advance of the pit in a <br />temporary moving stockpile, which is then loaded for permanent placement in the <br />regraded area. This loop road would move as the pit moves. A small topsoil berm a <br />minimum of 4 feet high will be placed at the advance edge of the pit so that all runoff <br />from the topsoil excavation area is trapped by this berm. <br />The suitable weathered upper overburden (Bench 1 or free dig material) is removed by <br />shovels and trucks and taken to the back of the pit for backfilling using the same loop <br />road. All of this suitable material is placed immediately below the topsoil and subsoil in <br />all areas. The thickness of this material typically varies from about 20 to 30 feet in the <br />NHN area to be mined (see maps 2.04.6 -4 and 2.04.6 -5) but may be thinner under small <br />drainages where erosion has removed some of the softer weathered overburden. The area <br />under Meehan Draw, (see Map 2.04.6 -1), will not be mined. The total amount of topsoil <br />and suitable subsoil must be at least 3 to 4 feet thick. <br />Section 2.05.4(2)(d) Page 3 January 2012 <br />