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TAB 14 <br /> BLASTING <br /> Introduction <br /> Prior to removal, the overburden and parting material must be fragmented to a size which <br /> can be handled efficiently by excavation equipment. Likewise, the coal must be fragmented <br /> prior to loading into haulage trucks for transport to coal handling facilities. The <br /> majority of the fragmentation will be accomplished by the use of explosives. When <br /> possible, overburden, parting and coal will be fragmented by ripping with a <br /> ripper-equipped dozer. The objective of this process is to provide fragmented overburden, <br /> parting material, and coal ahead of excavation and loading equipment so that production is <br /> sufficient to satisfy coal supply obligations. <br /> Blasting will be conducted to prevent injury to persons, damage to public or private <br /> property outside the permit area, adverse impacts to any underground mine, and change in <br /> the course, channel, or availability of ground or surface waters outside the permit area. <br /> Blasting will be conducted in accordance with all applicable State and Federal laws. <br /> The following discussions describe the drilling and blasting procedures that will apply to <br /> both the existing Nucla Mine and the proposed Nucla East areas. Should a discussion apply <br /> only to one of the operations, the particular discussion will identify the specific area. <br /> Blasting Procedures <br /> Vegetation is cleared from the undisturbed surface and suitable topsoil removed prior to <br /> drill bench preparation and drilling overburden. A drill hole pattern is determined on <br /> the basis of the thickness and physical characteristics of the material to be fragmented <br /> and the size of the excavator or loader. The overburden above the Dakota coal seam <br /> consists of a poorly cemented sandstone, argilaceous shale, and a calcareous caprock. <br /> This overburden will be drilled by a rotary blast hole drill with pattern hole spacings <br /> varying from 9' x 12' to 18' x 211. <br /> After the holes are drilled, they will be loaded with a blasting agent. The blasting <br /> agent will be either ammonium nitrate and fuel oil (ANFO), a high energy emulsion, or a <br /> 14-1 Revised 04/11/88 <br />