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Typical overburden/interburden handling operations are described in Section 2.05.3, Operation Plan and Section 2.05.4(2)(c), Backfilling and Grading. The overburden/interburden material excavated by truck and shovel from the cropline pit is placed in box cut spoil stockpiles as shown on Map 2.05.4-1, Operations Plan -New Horizon 2. Based upon the existing spoil stockpile at New Horizon 1 mine area, the overburden/interburden will likely be stratified by individual distinct lifts of different lithologic material. Lithologic Unit 1 material will typically be placed near the base of the stockpile with a thin topdressing of Units 2, 3, and 4. As the stockpiled material is returned to the final pit, mixed Units 2, 3, and 4 will be placed near the pit base and subsequently covered with Unit 1 material. Mixed Units 2, 3, and 4 have mean pH and ABP values of 6.0 and -1.8, respectively, which are both considered suitable for aquifer or root growth medium material (Section 2.04.6, Table 2.04.6-3), The following overburden/interburden handling Techniques are being utilized after the lower Dakota Coal has been removed from the box cut pit. Initially, the upper unconsolidated overburden is removed by shovel and trucks and placed into the adjacent pit void. Cast blasting Is being utilized, when possible, to fracture the remaining consolidated overburden/interburden. • During cast blasting, portions of Units 2, 3, and 4, in addition to the lower part of Unit 1, will likely be projected into the adjacent pit. Lastly, dozers, trucks and shovel will be utilized to remove the remaining overburden/interburden material down to the top of the Lower Dakota Coal. Where blending or normal burial are iheffective (as defined by the Regraded Spoil Monitoring Program), Unit 1 overburden will be selectively handled to replace afour-toot root growth medium at the regraded spoil surface. In these situations, unsuitable spoil will be topdressed with a minimum of four feet of suitable material (includes replaced topsoil thickness). Lastly, ameliorating reclamation practices will primarily be utilized in those areas where unsuitable spoil reaction, acid-base potential, particle size, saturation percentage, salinity, or sodicity values are identified by the regraded spoil quality control program. Reclamation practices will include either a selectively handled suitable spoil topdressing or incorporating adequate quantities of agricultural grade limestone. (Revised s-is-zoom 2.05.4(2)(d)- 3