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The fine refuse (-35 mesh particles) which has been thick- I ened in the static thickener to a 25 to 30 percent solids consistency is pumped underground separately. ~ Below ground the fine refuse is clarified and dewatered by a solid bowl scroll type centrifuge. The coarse refuse is dewatered on a single deck screen. Effluent from the centrifuge and drainage from the screen is collected in a common sump and returned to the coarse refuse slurry tank and static thickener at the wash plant. In this fashion the water circuit becomes close-looped and any fines generated during coarse slurry haulage will eventually be captured as thickener underfloor and subsequently removed and dewatered on their return trip ~ to the mine. The dewatered solids are fed to the pneumatic ~ feeder by conveyor and pneumatically transfered 1000 feet for placement in the appropriate mine location. ~ During emergency situations both slurry lines can be emptied into an underground emergency storage sump. If the underground slurry system remains inoperative, the wash plant can continue operation by discharging its coarse refuse through the dewatering screen/storage bin system and pumping its fine refuse (thickener underfloor) to the existing underground fine refuse disposal pond. As solids settle in the emergency storage sump and the fine refuse disposal pond, clarified water is returned to the wash plant. Above Ground System Much of the above ground system equipment presently exists •' as indicated in the wash plant flow sheet (see Figure 3). Esisting components include: a. Flop gate and Chutes b. Double-deck dewatering screen c. Coarse refuse emergency storage hopper (100 ton) d. Static thickener. Components which will require purchasing or can be made through modifications to existing equipment include: a. Thickener underfloor pump b. Coarse refuse crusher c. Coarse refuse slurry tank ~ d. Coarse refuse slurry pumps. •f