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Ditch ll-2 was relocated to the south, paralleling the Refuse Httukaad, two culverts were added undo the
<br />Washplant II yard-area access, and the eastern inlet to Sedimctrtation Pand 17 was shifted to the south and
<br />west, Contributing watershcci areas and conditions did not change sigtzificantly, ditch and culverts sixes
<br />were maintained, and ditch condition and configuration were iznprnved, therefore, revised drainage
<br />calculations were not necessary,
<br />Washplant construction would eneroac#a on the existing Pand D emergency spillway, sa the spillway was
<br />relocated to the canter of 4he Pond SI embankment, near the principal spillway. T's laaatian also improves
<br />pond function by increasing the distarx:e between the pond inlets and emergency spillway and improving
<br />routing.
<br />As part of the design process, four sail borings were completed for design of the foundation stntctures far the major
<br />Washplant facilities {refer to Washplant II Foundation E7esigtt kepart in 1*<~thibit 2S}, Site backfill and grading
<br />work far Washplant II hrvolved removal of potentially unsuitable soil materials, ripping and scarification of'the
<br />entire Washplant pad area, out and fill grading, and controlled placement and compaction. Cut volumes were
<br />approximately 24,4t10 cy, and appmximately 12,OOQ ay of suitable fill and 10,000 c;y of graded rock material were
<br />placed and compacted, consistent with the foundation design r~azntrtendatians. ~aek'f`illod and compacted pad
<br />areas were then graded to direct surface runoff flaws to the designed drainage and sediment control structures, and
<br />(except far building foundation areas} graveled to central eroaian, dust, and surface drainage. Graveled areas will
<br />be utih2ed as yatti-area driveways for cquipzztent and operations/maintenance at=cess to the CrushinglSeeening
<br />Building, Washplant, thiakaner, and Refuse lain. E3ased on the foundation design rer.,otnmendatiozts, reinforced
<br />concrete caissons were poured to suppr}rt building fvundatians and conveyer supports. KcinForced concrete floor
<br />slabs and grade walls were then famttxi and poured to connect to the concrete caisson support system,
<br />The initial segtrzent of the existing Overland C;anveyor was rcplactxl with an inclined Ctushing/Screening Feed
<br />canveyar {4$-inch belt wl2,200 tph capacity} extending 420 feat from the Raw Caal Staakpila reclaim to the new
<br />Screening Tower. The inclined conveyor segment is supported by Iwo steel support bents, and typical canveyar
<br />construction consists df a steel rail framework supporting the traughing and return idlers, with an adjacent cat-walk
<br />and railings for maintenance, and'!< coverage galvani2ed skecl covers to central dust and noise. The canveyar bents
<br />set an reinforced concrete caissons, as previously described.
<br />From the C'rushinglScreenin$ Feed Conveyor, the coal discharges through a chute and feeders to double-heck
<br />screens which separate the coal fend into three size Tracts"ens; an undersize fraction { Yx" x 0") which passes ihxaugh
<br />and discharges directly to the tverland Conveyor; an intermediate fraction (%x" x 2"} which transfers to the
<br />Washplant Feed Conveyor; and the soreen oversize (+2") which discharges to aroll-crusher, with the Crushed
<br />product transferring it) the Washplant Feed canveyar, Ely-pass chute-work allows the intertediate and crushed
<br />products to be diverted directly to the Overland canveyar, if plant feed coal quality precludes the need far waslzizzg.
<br />The crashing and screeniztg equipment, slang with associated chute-work, and cantml, monitariztg and dust
<br />collection systems, are housed in the Crushingl$creening Huitding, a steel frame building with steel siding and mof
<br />(50 x 6t1 x 80 feet high), which sets dis~eatly over the C)verland Conveyor, The building sets an a reinforced
<br />cancretc slab Haar {52 x 62 x I feat think} with grade wails connected to the ccrncretc aaissan support system, as
<br />previously described.
<br />A two-flight Washplant Feed Conveyor (~l8-inch bait w12,200 tph capacity) and Transfer Tower (20 x 20 x 40 foot
<br />high} transfer the intermediate and crushed Ural praduats from the bottom of zttc CrushinglScrcetzing Building to
<br />the tap of the new Washplant II E3uilding, The Washplant Feed Conveyor system is designed to handle current
<br />requirements of 1,300 tph, as well as passible future systcxm expansion. I"ach of the two canveyar flights is
<br />supported by a single steel support beat, and ufihxe the typical canveyar canattuction. The conveyor bents set an
<br />reizforced concrete caissons, as previously described. Tire intermediate Transfer Tower is a steel frame building
<br />with steel siding and roof which contains minor chute-work and a dust ~Ilectian system, The Transfer Tower sets
<br />cJn a reinfaz~ced concrete stab tlaor {22 x 7.2 s 1 feat thick'}.
<br />2A5-32,3
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