_GENERAL DOCUMENTS - C1981017 (263)

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placed over a system of French drains designed to carry entrained water and ground water away from the base of the fill. The refuse was compacted in shallow lifts that were gently inclined toward the face of the fill to encourage moisture drainage, should rainfall become entrained in the material during construction. Each lift was compacted prior to placing the overlying lift. The regarded surface was loosened and covered as described for the Huntsman Project except that the earthen material was clearly lacking in organic matter. Approximately two tons per acre certified weed free straw mulch was applied over the top of the dirt layer. The slope interruption method used at the Huntsman was not contemplated at Bear Creek, because the slope length was much greater here. Therefore the potential of runoff achieving erosive velocities was much greater. Because of the greater slope length, a more disruptive soil surface had to be developed. Contemporaneous with application of the straw mulch to the soiled slope surface, a light track excavator was positioned at the top of the slope. The excavator would extend its arm uphill of the tracks in a 180 degree radius, and punch the bucket into the ground surface approximately twelve inches. The operator would then curl the bucket toward the excavator, mixing a small amount of coal refuse,the dirt and the straw mulch together, while creating a pocket twelve inches deep by the width of the bucket,by about eighteen inches in length. Pockets were created immediately adjacent to one another in a random pattern across the entire face of the facility. The close spacing,but limited size, of these pockets provided three important qualities; the straw mulch was thoroughly mixed with the dirt to incorporate the organic matter into the growth medium, a small amount of dirt from one pocket would fall into the downslope pocket,thus covering exposed coal refuse with a small amount of growth medium, and surface water flow paths and velocities were drastically reduced, thus resulting in a greatly diminished erosion potential across the entire facility. Additional benefits to this technique included the creation of thousands of microclimates to enhance revegetation potential, and a more natural look to the reclaimed facility than what would have resulted from construction of berms or terraces. Locally obtained willow cuttings were placed at the toe of the western(wetter)half of the fill slope, while containerized shrubs were planted at the toe of the eastern half of the fill slope. Trees were planted in clumps at the top, near the mid-slope area and at the toe of the slope in an effort to mimic local growth patterns. 7