_GENERAL DOCUMENTS - C1981017 (229)

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Environmental Challenges The principle environmental challenges encountered when accomplishing reclamation at Coal Basin revolve around the steepness of the slopes, soil types and precipitation characteristics of the area. Intense summer thunder showers can cause a tremendous amount of short term, high intensity runoff. The soils within the Basin are generally derived from the Mancos Shale, and are highly erosive. The topographic relief of the Basin is very dramatic, as evidenced by the extremely steep slopes and deep, narrow canyons. Other challenges faced in accomplishing reclamation of the site are primarily related to the climatic conditions of the Basin. The short growing season at higher elevations limits the establishment of reclamation species. Vegetation establishment can require three or more years after initial seeding. Reclamation Projects, Bankruptcy Funds To date, approximately$1,238,000 has been expended to reclaim about 160 acres. Reclamation has been accomplished at three mine areas, the Rock Tunnel vicinity,three waste dumps, a warehouse/storage area, on nine miles of haul roads and at two coal stockpiles. Reclamation generally includes structural demolition, earth work, drainage construction and revegetation related tasks. The focus of most projects has been to overcome erosion resulting from mining related disturbances. To this end, the projects have included partial backfilling of highwalls, recontouring of the mine benches (above the outslopes to help alleviate the channelization of water from rainstorms), re-grading and ripping of road surfaces and revegetation. Erosion of the mine bench outslopes has been an ongoing concern. These slopes vary from between 100 feet and 900 feet in length, and are between one and eight acres in size. They are mainly composed of materials excavated to create the highwalls at the various mine entries, and approach the angle of repose in many cases. Stabilization of the outslopes through revegetation offers the best long term potential for minimizing erosion. Initially, revegetation was attempted at Mine 3 in 1995. A north facing slope was scarified by dragging a large steel I beam across the slopes to eliminate surface crusting. Seed, fertilizer and mulch were applied using a hydromulcher. Revegetation demonstrations were conducted at Mine 1 1996. A four-ton vibratory roller was converted into an imprinter by welding ten-inch long by six-inch tall steel plates perpendicular to the roller surface. These plates were placed in an alternating pattern across the roller surface. When suspended from a dozer, and rolled up and down the slope, a series of small benches was created on the face of the slope. These benches provided a surface for the seed to rest and germinate. Best results were achieved when the roller was used on slopes which exhibited a greater percentage of finer grained materials, and a lesser percentage of coarse material. After imprinting the slope, seed was hand broadcast, and the slope was mulched. Reclamation Projects,Abandoned Mined Land Funds To date, two Projects funded by Abandoned Mined Land Fees have been accomplished at Coal Basin. A third Project is scheduled for this summer and a fourth is being planned for 2001. Revegetation of an abandoned coal strip pit and an adjoining mine bench outslope near Mine 5 was undertaken in 1991. Additional work at a coal waste pile in the vicinity of Mine 5 will be proposed for construction in 2001. A portion of the Old Refuse Pile was constructed prior to August 3, 1977. This portion of the facility is very steep, with slope angles in some places exceeding one to one (horizontal to vertical). A number of slumps and slides, along with significant erosion, were observed in this area. In order to reduce erosion potential, and to minimize the possibility of a slope failure at this portion of the refuse pile, it was determined that slope reduction would be required. In order to address these concerns two AML funded Projects have been proposed: