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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 fi-om 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'/4 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
<br />screens which separate the coal feed into three size fractions; an under -size fraction (-/" x 0") which passes
<br />through and discharges directly to the Overland Conveyor; an intermediate fraction ('/z" x 2") which transfers to the
<br />Washplant Feed Conveyor, and the screen oversize (+2") which discharges to a series of two roll -crushers, with the
<br />crushed product transferring to the Washplant Feed Conveyor. The second roll crusher will be added in 2016 to
<br />address the harder parting material generated by development and mining in the Wolf Creek Reserve. The addition
<br />of this crusher within the existing Crushing/Screening Building will require extension of the building and
<br />foundation on the southeast side to provide for maintenance access, construction of two additional piers and a 20 -
<br />foot extension of the existing electrical room, and construction of an additional transformer pad. Support footers
<br />and piers (2 — 6' x 6' x 1.5' and 27" x 27" x 48"; 2 — 4' x 11' x 1' and 18" x 18" x 5'), foundation walls (1 — 8' x
<br />13' x 8"), transformer pad (10.5' x 12' x 1.5'), and floor slabs (total — 24 cy) associated with tills expansion will
<br />require placement of approximately 65 cy of additional reinforced concrete. Facilities dimensions, layouts, and
<br />design details for the expansion are provided in Exhibit 49K.
<br />By-pass chute -work allows the intermediate and crushed products to be diverted directly to the Overland Conveyor,
<br />if plant feed coal quality precludes the need for washing. The crushing and screening equipment, along with
<br />associated chute -work, and control, monitoring and dust collection systems, are housed in the Crushing/Screening
<br />Building, a steel frame building with steel siding and roof (50 x 60 x 80 feet high), which sets directly over the
<br />Overland Conveyor. The building sets on a reinforced concrete slab floor (52 x 62 x 1 foot thick) with grade walls
<br />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
<br />the top of the new, Washplant 11 Building. The Washplant Feed Conveyor system is designed to handle current
<br />requirements of 1300 tph, as well as possible future system expansion. Each of the two conveyor flights is
<br />supported by a single steel support bent, and utilize the typical conveyor construction. The conveyor bents set on
<br />reinforced concrete caissons, as previously described. The intermediate Transfer Tower is a steel frame building
<br />with steel siding and roof which contains minor chute -work and a dust collection system. The Transfer Tower sets
<br />on a reinforced concrete slab floor (22 x 22 x I 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
<br />both a coarse and fine coal product, which are combined and discharge to the Overland Conveyor. Coal refuse is
<br />separated from the coal stream in the cyclones, with the coarse refuse passing over screens to drain and then to the
<br />Coal Refuse Conveyor, and the fine refuse being transferred to the Thickener to reduce water content. The
<br />Washplant will require approximately 600 gpm of make-up water, to address losses to the coal product, coarse
<br />refuse, and tine refuse streams (note that most of the water from the fine refuse stream is recovered and recycled to
<br />the Mine water supply system, which include the wasllplant feed water). The coal preparation circuit also includes
<br />the magnetite recovery and recycling system, and a water filtration and recycle system, to minimize water use
<br />requirements. The coal preparation equipment, along with associated chute -work, and control and monitoring
<br />systems, are housed in the Washplant Building, a steel frame building with steel siding and roof (55 x 125 x 80 feet
<br />high), which sets directly over the Overland Conveyor. The building sets on a reinforced concrete slab (58 x 128 x
<br />I foot thick).
<br />The Coal Refuse Conveyor (48 -inch belt w/500 tph capacity), transfers coarse coal refiise 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
<br />Coal Refuse Disposal area. The Coal Refuse Conveyor is designed to handle current requirements of 500 tph, as
<br />MR 16-300 2.05-32.3 06/21/16
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