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• SENECA COAL COMPANY HISTORY AND BACKGROUND Seneca Coal Company operates 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-Westin 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 Seneca Coal Company is evident even within a climate of changing regulations, high altitude, and very steep slopes. The terrain and climate provide interesting, and infra ~ing challenges to mining and reclamation technology, equipment operatioq post mine conto»~ and revegetatioa. 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 Seneca reclamation is wildlife habitat and livesrock grazing. Most of this land was overgrazed prior to mining and invasive weeds continue to be a challenge. Woody shrubs and trees aze difficult to establish. The post mine terrain is steep, up to 33%, resulting in significant erosion potential and the necessity for intensive pemtanent 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. u 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 Srneca 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 azeas of overburden thicknesses ranging from 15 to +100 feet, which lends itself to azea surface mining by dragline. Mining is conducted with a BE 770 dragline (18 ar. 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 what would be considered a conventional dragline-mining plan. Photo 1 gives a good view of the type of retrain that mining operations aze conducted on. RECLAMATION PRACTICES All backfilled and graded spoils aze graded to create irregular topographic undulations. In addition, reclaimed areas with an overall slope grade of 30% or more require special attention which is described in more detail under the heading Top Soil Replacement Permanent drainage channels aze constructed to control and prevent undue erosion while revegetation is establishing. TopsoIl handling is conducted with dozers and scrapers. Live handling of topsoil has only been done on limited basis due to mining azea configurations. The majority of the topsoil has been placed • in storage stockpiles for periods of three years or more before replacement