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<br />blasting agent and detonated. A dragline then removes the overburden and exposes <br />the coal. The cuts exposed by the dragline are up to a mile long and two hundred <br />feet wide at the bottom of the pit. <br />After the coal seam is exposed, the coal is drilled and blasted. A hydraulic back- <br />hoe then loads the coal into end dump trucks which deliver the coal to the Craig <br />Generating Station. <br />There are three walking electric draglines at the Trapper Mine. The draglines are <br />the primary tools for removing the overburden (waste material) and uncovering the <br />coal. (Refer to Attachment 3) <br />Statistics-for the Draglines are: <br />Length of Boom .305 Feet <br />Suspended Load from Boom. 148,000 lbs. <br />Maximum Digging Depth. .170 Feet <br />Weight . 3 , 666 , 000 lbs. <br />Shoe Area 514 Sq. Ft. (10' 6" x 49' 0" ) <br />Normal Length of Step. .6 Ft. 10 in. <br />Bucket Capacity. .30 Cubic Yards <br />Hoisting Capacity of Bucket. .139,000 lbs. <br />Each dragline took approximately one year to erect at an approximate cost of <br />$7,000,000. Today's price would be about $14,000,000. The cost of electricity for <br />a single dragline for one month is about $25,000. <br />