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State Reg. <br />benefits of this method are notable. The first is that • <br />reclamation to approximate original contour (4.14.1) is easier <br />and more efficient with spoil ridges oriented parallel to the <br />dip of the slope. Also, working a pit from recovery line to <br />cropline (deep to shallow overburden) in each area has the <br />advantage of averaging the costs of production from month to <br />month and year to year for the life of the operation. The <br />following narratives detail the current and projected method <br />of overburden handling at Seneca II P1ine. <br />The phase following the blasting of the overburden is the <br />removal of the overburden material and consequent uncovering <br />of the coal seam. At Seneca II, the overburden is excavated <br />primarily by two electrically powered Bucyrus-Erie draglines. <br />The two models currently in use are: 1) the 770-8 with an 18 <br />cubic yard bucket, 211-foot operating radius and I00-foot <br />dumping height; and 2) the 650-B with a 16 cubic yard bucket, <br />203-foot operating radius, and 100-foot dumping height. • <br />Overburden removal takes place continuously, three shifts per <br />day, six days per week, although shallow overburden or adverse <br />market conditions may allow for reduced shifts of less than <br />six days per week. <br />To begin mining in a new coal area, the dragline is typically <br />positioned on the highwall at the cropline to excavate a box <br />cut. The dragline will develop the box cut pit approximately <br />75 to 100 feet in width, advancing the cut down dip. <br />Subsequent pit widths will vary with depth and overburden <br />condition, but will generally be maintained 75 to 125 .feet <br />wide at the top-of-coal surface. During the box cut <br />excavation, the dragline places or spoils the overburden <br />material along the side of the cut onto previously unmined ~~ <br />ground opposite the direction of mining progression. Spoil <br />material from subsequent cuts is placed in the preceding open <br />pit after the coal has been removed. Following excavation of <br />each cut, the dragline "scales" the highwall with the bucket • <br />and drag chains to pull down any loose or projecting material <br />that might be a safety hazard to those working in the pit. <br />12-48 P.evised 05/16/88 I <br />