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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 can be <br />handled efticiently by excavation equipment. Likewise, the coal must be fragmented prior to loading <br />into haulage trucks for transport to coal handling facilities. The majority of the fragmentation will be <br />accomplished by the use of explosives. When possible, overburden, parting and coal will be <br />fragmented by ripping with a ripper-equipped dozer. The objective of this process is to pro~+ide <br />fragmented overburden, paving material, and coal ahead of excavation and loading equipment so that <br />production is sufficient to satisfy coal supply obligations. <br />Blasting will be conducted to prevent injury to persons, damage to public or private property outside <br />the permit area, adverse impacts to underground mine workings, and change in the course, channel, or <br />availability of surface or ground waters outside the permit area. Blasting will be conducted in <br />accordance with all applicable State and Federal laws. <br />The following discussions describe the drilling and blasting procedures that will apply to the Yoast <br />Mine. <br />Blasting Procedures <br />Vegetation is cleared from the undisturbed surface and suitable topsoil removed prior to drill brnch <br />preparation and drilling overburden. A drill hole pattern is determined on the basis of the thickness and <br />physical characteristics of the material to be fragmented, the size of the excavator and drill, width of <br />pit, and type of explosive. The overburden above the coal consists of a hard, fine-grained sandstone, <br />and soft to slightly hard shale. This overburden will be drilled by a rotary blast hole drill with pattern <br />hole drill with pattern hole spacings varying from 18' x 21' to 30' x 35'. If the spacing is greater than <br />28 feet, close attention will be paid to seismic monitors at the nearest residence to ensure compliance. <br />After the holes are drilled, they will be loaded with a blasting agent. The blasting agent will be either <br />ammonium nitrate and fuel oil (ANF01, a high energy emulsion, or a packaged slurry product. The <br />blasting ratio, pounds of overburden per pound of explosive, will vary from .85 to 1 to 3 to 1 <br /> <br />Revised 2/02 <br />