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After removal of the overburden, the coal seams are exposed. As the coal seams are exposed, <br />they are cleaned using auxiliary equipment then either drilled and shot with explosives or <br />ripped to prepare the coal for loading and removal. <br />When explosives are needed, the drilling is performed by an auger drill. The drilling pattern <br />is in the range of 12 feet by 12 feet, but is dependent upon the actual coal seam thickness. <br />Drill holes are loaded with either ANFO or a waterproof explosive, if the holes are wet, to a <br />typical powder factor of about 0.2 pounds per ton. <br />2.05-9 Revision Date: 12/15/05 <br />Revision No.: MR-76 <br />