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When removed by dozers, the topsoil is pushed into piles and loaded into haulage trucks <br />for transport to stockpiles or regraded spoils. In addition to haulage to remote stockpiles, <br />topsoil windrows may be left in place at fhe edge or perimeters of disturbance areas. <br />Dozers or scrapers are used to redistribute topsoil. Topsoil stockpiles will be strategically <br />located in stable areas to avoid both wind and water erosion, disturbance, unnecessary <br />compaction, and contamination. In addition, topsoil stockpiles will be appropriately <br />marked with conspicuous signs made of durable material. When stockpiles are no longer <br />active, they will be graded with a dozer. To further prevent erosion, seeding of stockpiles <br />will be accomplished according to procedures described in Section 2.05.4. <br />Topsoil removal schedules and stockpile locations are delineated on the Topsoil <br />Handling Maps 28A and Map 28B. The amounts of topsoil to be removed and replaced <br />are found in Table 1, Topsoil Schedule for Mining Area, and Table 2, Topsoil Removal <br />Plan. Topsoil will be removed from an area primarily during the summer and fall months <br />to allow for one years mining advance. A buffer zone, with topsoil removed, will be left <br />between the undisturbed area and the crest of the pit. <br />Following topsoil removal, the next step is drill bench preparation and the drilling and <br />blasting of the overburden material. Colowyo maintains and operates several rotary drills <br />for penetrating the overburden and interburden material. Dozers are used to construct a <br />drill bench, a level area for the drill to work on. The overburden drill then drills a pattern <br />of holes to either a predetermined sub-grade depth or to the top of the coal seam. The <br />spacing of the holes will be dependent upon the overburden thickness, but usually will <br />be in the range of 25 feet by 25 feet. Holes will be loaded with either ANFO or a <br />waterproof explosive, if the hole is wet, to a typical powder factor of between 0.5 and 1.2 <br />pounds per bank cubic yard. The hole will then be stemmed with drill cuttings and <br />blasted in accordance with detailed descriptions given in Section 2.05.3 under the <br />heading of Overburden. <br />2.05-3 <br />July 2, 2002 <br />MR-57 <br />CF 4.1.1.3 <br />