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The initial segment of the existing Overland Conveyor was replaced with an inclined Crushing/Screening Feed
<br />Conveyor (48-inch belt w/2,200 tph capacity) extending 920 feet from the Raw Coal Stockpile reclaim to the new
<br />Screening Tower. The inclined conveyor segment is supported by two steel support bents, and typical conveyor
<br />construction consists of a steel rail framework supporting the troughing and return idlers, with an adjacent cat-walk
<br />and railings for maintenance, and 3/ coverage galvanized steel covers to control dust and noise. The conveyor bents
<br />set on reinforced concrete caissons, as previously described.
<br />From the Crushing/Screening Feed Conveyor, the coal discharges through a chute and feeders to double-deck screens
<br />which separate the coal feed into three size fractions; an undersize fraction (-'/z" x 0") which passes through and
<br />discharges directly to the Overland Conveyor; an intermediate fraction ('/z" x 2") which transfers to the Washplant
<br />Feed Conveyor; and the screen oversize (+2") which discharges to aroll-crusher, with the crushed product transferring
<br />to the Washplant Feed Conveyor. By-pass chute-work allows the intermediate and crushed products to be diverted
<br />directly to the Overland Conveyor, if plant feed coal quality precludes the need for washing. The crushing and
<br />screening equipment, along with associated chute-work, and control, monitoring and dust collection systems, are
<br />housed in the Crushing/Screening Building, a steel frame building with steel siding and roof (50 x 60 x 80 feet high),
<br />which sets directly over the Overland Conveyor. The building sets on a reinforced concrete slab floor (52 x 62 x 1 foot
<br />thick) with grade walls connected to the concrete caisson support system, as previously described.
<br />A two-flight Washplant Feed Conveyor (48-inch belt w/2,200 tph capacity) and Transfer Tower (20 x 20 x 40 foot
<br />high) transfer the intermediate and crushed coal products from the bottom of the Crushing/Screening Building to the
<br />top of the new Washplant II Building. The Washplant Feed Conveyor system is designed to handle current
<br />requirements of 1,300 tph, as well as possible future system expansion. Each of the two conveyor flights is supported
<br />by a single steel support bent, and utilize the typical conveyor construction. The conveyor bents set on reinforced
<br />concrete caissons, as previously described. The intermediate Transfer Tower is a steel frame building with steel siding
<br />and roof which contains minor chute-work and a dust collection system. The Transfer Tower sets on a reinforced
<br />concrete slab floor (22 x 22 x 1 foot thick).
<br />• The Washplant Feed Conveyor discharges to a surge bin, with water added at the transfer point. Feeders draw from
<br />the surge bin to feed the coal to a series of screens, heavy-media cyclones (using a slurry of magnetite and water to
<br />separate the coal from the heavier refuse material), classifying cyclones, wash screens, and centrifuges, producing both
<br />a coarse and fine coal product, which are combined and discharge to the Overland Conveyor. Coal refuse is separated
<br />from the coal stream in the cyclones, with the coarse refuse passing over screens to drain and then to the Coal Refuse
<br />Conveyor, and the fine refuse being transferred to the Thickener to reduce water content. The Washplant will require
<br />approximately 350 gpm of make-up water, with approximately 100 gpm coming from water recycled from the process,
<br />and losses of approximately 190 gpm to the coal product stream, 35 gpm to the coarse refuse stream, and 25 gpm lost
<br />to the fine refuse stream (the remainder of the water from the fine refuse stream is recovered and recycled to the Mine
<br />water supply system. The coal preparation circuit also includes, the magnetite recovery and recycling system, and a
<br />water filtration and recycle system, to minimize water use requirements. The coal preparation equipment, along with
<br />associated chute-work, and control and monitoring systems, are housed in the Washplant Building, a steel frame
<br />building with steel siding and roof (55 x 125 x 80 feet high), which sets directly over the Overland Conveyor. The
<br />building sets on a reinforced concrete slab (58 x 128 x 1 foot thick).
<br />The Coal Refuse Conveyor (48-inch belt w/500 tph capacity), transfers coarse coal refuse from the Washplant to a
<br />Refuse Bin. The Refuse Bin is used to load trucks, which haul the coal refuse material to the existing permitted Coal
<br />Refuse Disposal area. The Coal Refuse Conveyor is designed to handle current requirements of 500 tph, as well as
<br />possible future system expansion. The Refuse Conveyor is supported by two steel support bents, and utilizes the
<br />typical conveyor construction. The conveyor bents set on reinforced concrete caissons, as previously described. The
<br />Refuse Bin is a steel frame building (30 x 30 x 50 feet high) with steel siding and roof which supports a 200-ton pre-
<br />fabricated steel surge bin and contains minor chute-work and a dust collection system. The Refuse Bin sets on a
<br />reinforced concrete slab floor.
<br />• The Washplant II Thickener, which is used to partially dewater the fine coal refuse, is a reinforced concrete tank
<br />approximately 50 feet in diameter, and 12 feet high. A flocculating agent is introduced into the tank, and a high-
<br />TR08-65 2.05-32.3 07/08/08
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