2008-02-08_GENERAL DOCUMENTS - C1982057

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SENECA COAL COMPANY HISTORY AND BACKGROUND Seneca Coal Company (SCC) operated the Seneca II, Seneca II-West, and the Yoast Mines in Northwest Colorado. Seneca Coal Company began coal production in 1968 at the Seneca II Mine. The mining progressed to Seneca II-West in 1990 and to Yoast in 1996. Coal production totally ceased in 2005 leaving 4,000 acres of reclaimed land within the Seneca mining complex. The success of the reclamation program at SCC is evident within a climate of changing regulations, high altitude, and very steep slopes. The terrain and climate provide interesting, and intriguing challenges to mining and reclamation technology, equipment operation, post mine contouring and revegetation. The coal lies in a 20-35% pitching grade. The terrain varies in elevation from 6,300 feet to 8,500 feet. The climate in Northwest Colorado provides a 65- day growing season. The annual precipitation is 17 inches of moisture, mostly in the form of snow. The post mine land use for SCC reclamation is wildlife habitat and livestock grazing. Most of this land was overgrazed prior to mining and invasive weeds continue to be a challenge. Woody shrubs and trees are difficult to establish. The post mine terrain is steep, up to 33%, resulting in significant erosion potential and the necessity for intensive permanent drainage channel construction. Even with these adverse conditions, successful reclamation is achievable. The following narrative describes the overall reclamation practices at the Seneca II-West Mine. GENERAL OPERATIONS Normally, area surface mining is restricted to coal reserves which lie in a relatively level plane below a level or gently rolling surface terrain. However, at Seneca II-West, the geologic structure is such that the coal seam outcrops at the top of the mountain and dips at 18 to 33 percent, while the overlying surface dips at approximately 18 to 35 percent. This results in areas of overburden thicknesses ranging from 15 to over 100 feet, which lends itself to area surface mining by dragline. Mining was conducted with a BE 770 dragline (18 cu. yd. bucket) with maximum digging depth of 100 feet. The relatively high angle of dip on the coal seam and surface requires some creative modification of conventional dragline-minuig methods. RECLAMATION PRACTICES All backfilled spoils are graded to create irregular topographic undulations. In addition, reclaimed areas with an overall slope grade of 30% or more require special attention. Permanent drainage channels are constructed to control and prevent undue erosion while revegetation is established. Topsoil handling is conducted with dozers and scrapers. Live handling of topsoil has only been done on limited basis due to mining area configurations. The majority of the topsoil has been placed in storage stockpiles for periods of three pears or more before replacement Topsoil is replaced to a depth of 18 inches overall with thicker placement in tree establishment plots.