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' When removed by dozers, the topsoil is pushed into piles and loaded into <br />haulage trucks for transport to stockpiles or regraded spoils. In <br />addition to haulage to remote stockpiles, topsoil windrows may be left in <br />place at the edge or perimeters of disturbance areas. Dozers or <br />scrapers are used to redistribute topsoil. Topsoil stockpiles will be <br />strategically located in stable areas to avoid both wind and water <br />erosion, disturbance, unnecessary compaction, and contamination. In <br />addition, topsoil stockpiles will be appropriately marked with <br />conspicuous signs made of durable material. When stockpiles are no <br />longer active, they will be graded with a dozer. To further prevent <br />erosion, seeding of stockpiles will be accomplished according to <br />procedures described in Section 2.05.4. <br />Topsoil removal schedules and stockpile locations are delineated on the <br />Topsoil Handling Map, (Map 28). The amounts of topsoil to be removed and <br />replaced are found in Table 1, Topsoil Schedule for Mining Area, and <br />Table 2, Topsoil Removal Plan. Topsoil will be removed from an area <br />primarily during the summer and fall months to allow for one years mining <br />_ advance. A buffer zone, with topsoil removed, will be left between the <br />• undisturbed area and the crest of the pit. <br />Following topsoil removal, the next step is drill bench preparation and <br />the drilling and blasting of the overburden material. Colowyo maintains <br />and operates several rotary drills for penetrating the overburden and <br />interburden material. Dozers are used to construct a drill bench, a <br />level area for the drill to work on. The overburden drill then drills a <br />pattern of holes to either a predetermined sub-grade depth or to the top <br />of the coal seam. The spacing of the holes will be dependent upon the <br />overburden thickness, but usually will be in the range of 25 feet by 25 <br />feet. Holes will be loaded with either ANFO or a waterproof explosive, <br />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 <br />cuttings and blasted in accordance with detailed descriptions given in <br />Section 2.05.3 under the heading of Overburden. <br />%. 2 . 0 5 - 3 Revision SebmiGed b -13 - o ~ <br />Revision No. -~- R - s 3 <br />