2012-07-11_PERMIT FILE - C1984065 (2)

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done by mechanical means, no chemicals or thermal drying will be • performed. As the slurry enters t}~e process building, it will pass over a static sieve as the initial dewatering process. From there it will pass to a double deck vibratiny-screen for additional dewatering and sizing. The top screen size will be 1 1/9 inch and the bottom screen will be 3/8 of an inch. Coal particles large than 1 1/9 inch will be crushed to a maximum size of 2 1/2 inch, a size normally specified by utilities. This coal size does not require any dewatering and will go from the crusher directly to the coal storage pile. Coal size 3/8 inch x 1 1/4 inch will be dewatered in a coarse coal centrifugal dryer and will be directed to the specialty coal pile (stoker) or to the main coal pile. Coal sizes minus 3/S inch will be directed from the sump beneath the double deck screen to a fine coal sieve and from there to a fine coal screen. The product from this screen will be dewatered in a fine coal centrifuge and be • directed to the main coal stock pile. The underfloor, together with the underflows from the main vibrating screen and sieves, will be piped to the static thickener. The thickener is a round 50 foot diameter concrete vessel, the primary function of which is a settlement basin. The decanted water from this thickener will be piped back into the mine water system for recycling back in the hydraulic circuit. The underfloor will be directed to a pair of belt presses (filters) for dewatering. The filter cake will go to the main coal stockpile, while the effluent water, which will contain very small particles (350 mesh or less), will be directed to the mine hydraulic circuit return for reuse within the mine. During full production (after 4 to 5 years of developement and operation), a small jig may be added to wash the coarse (plus 1 1/9 • NCIG - Coal Ridge #1 4-23 ASC/1145/910509 7h-7