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Placement and Compaction <br />The coal mine waste material will be hauled by truck to the refuse disposal area where it <br />will be spread in maximum lifts of 24 inches and compacted. The top of the pile will be <br />sloped to the east and west to ensure runoff from the fill surface flows to the collection <br />ditches and is not allowed to flow over the outslope of the fill. A berm will be maintained <br />to assure water does not flow over the outslope. <br />Coal mine waste will be placed and compacted to 90 percent of the maximum dry <br />density to prevent spontaneous combustion and to provide the strength required for <br />stability of the refuse pile. Dry densities will be determined in accordance with AASHTO <br />T99-74. The placing and spreading of the coal mine waste will be started at the lowest <br />point of the foundation. The coal mine waste will be keyed into the natural ground. <br />Materials will be spread in approximately horizontal lifts no more than 24-inches thick, <br />and such lifts made uniformly over long stretches. Each lift will be moistened or dried to <br />a uniform moisture content suitable for maximum compaction. Compaction will be <br />carried to the edge of the fills so that the final slopes are firm. The fill will be shaped and <br />benches (terraces) constructed as shown on Figure 1 and in accordance with the design <br />parameters listed above. <br />Compaction tests will be taken at a frequency and location of not less than one per every <br />other layer, at random locations across the pile. Test locations and results will be <br />reported to the Division in the appropriate construction reports. <br />Coal mine waste materials from activities located outside of the permit area, such as <br />those activities at other mines or abandoned waste piles, will not be placed in the coal <br />mine waste bank unless approved by the Division. <br />A gob drying area will be established between gob piles no. 1 and 2 on the bench <br />created by the coverfill borrow area (Ref. TR-43). During the winter months, gob will be <br />placed and compacted on this bench until such time either gob pile no. 1 or 2 is in <br />suitable shape (dry enough) to accept this material. At that time the gob will be removed <br />from the drying area and placed and compacted in one of the permanent piles. The use <br />of the gob drying area will be seasonal and it will only be used when the permanent gob <br />piles lack room for the drying necessary to properly place and compact the gob. At no <br />time will the drying area contain more than twenty vertical feet of material. The face of <br />the drying area material will be constructed with a 3H:1V slope. Placement and <br />compaction in the gob drying area will be performed as detailed in the second paragraph <br />of this section. <br />MR-76 - 9 - 01/09/07 <br />f1/PROVED <br />I/9~a7 <br />