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Overburden and Topsoil Handling Plan <br />Introduction <br />This section outlines New Horizon North Mine's plan for removal, storage and redistribution of <br />topsoil and overburden to meet the requirement of Section 2.05.3(5), 2.05.4(2)(d) and 4.06 for <br />the NHN permit application. The plan addresses those reclamation activities that are conducted <br />during and immediately after backfilling and grading but prior to revegetation. The objectives of <br />the plan are to reconstruct plant growth and aquifer mediums that are consistent with the <br />postmining land uses. The plan also describes the procedural aspects of removal, storage and <br />distribution of topsoil and weathered overburden (Bench 1) and testing of Bench 1. <br />Overburden and Bench 1 Handling Plan <br />The description of overburden and interburden characteristics and acid and toxic forming <br />materials for NHN Mine are presented in Section 2.04.6: Geology Description. Overburden and <br />interburden suitability and lithologic units for the NHN permit area are the same as the <br />overburden units at the New Horizon 1 Mine area. The NHN area incorporates a large portion of <br />the previously mined New Horizon 1 Mine area. <br />Weathered overburden, also called Bench 1 or free dig material (herein will be referred to as <br />Bench 1), will be mined separately from the other unweathered overburden materials (herein will <br />be referred to as overburden). The Bench 1 material is typically comprised of unconsolidated <br />material and will be mined in a single bench. It is then hauled and placed on top of the backfilled <br />overburden. All of the Bench 1 is placed immediately below the topsoil in all areas. Bench 1 in <br />its natural state, typically varies from about 20 to 30 feet in thickness within the permit area (see <br />Maps 2.04.6-4 and 2.04.6-5), but may be thinner under small drainages where it has been eroded. <br />During the reclamation process, Bench 1 will be used to cap all overburden and the carbonaceous <br />remnants of mining the UD, and LD,, seams. The cap of Bench 1 will reduce the potential of <br />leachates and runoff from entering the ground water system or discharging into the surface water <br />system. No roads will be surfaced with unsuitable material. <br />Prior to topsoil replacement, Bench 1 will be scarified by deep ripping on the contour at least 24 <br />inches on 24 inch centers to reduce excessive compaction, prevent potential slippage zones, <br />reduce erosion, and improve water and air movement and root growth across the Bench <br />1/overburden interface. Abandoned roads shall also be ripped prior to topsoil replacement. <br />Overburden Spoil Compactibility and Erodibility <br />Determining the compaction potential of the overburden backfill material is important to assess <br />postmining conditions including: hydraulic conductivity, revegetation success, landscape <br />stability and equipment traffic. Unsuitable clay textures are identified in two thin clay beds <br />Section 2.05.4(2)(d) Page 1 January 2018 (PR -02) <br />