Bill, a very good explanation of the coal preparation, if it was similar to the plants i'm familiar with there was another two important processes, one to recover the expensive magnetite and one to recover the fine coal washed off the screens.
The magnetite was recovered using a large drum that was an electromagnet on one side, as it turned the magnetite clung to the upward turning of the drum but dropped off the downward side which wasn't magnetic, and recycled.
The fine coal washed off the screens was mixed with more water and an added flocculant, a chemical that created lots of bubbles when injected with compressed air, the bubbles were skimmed off and then flowed through a tank that had large wheels made up of metal mesh screen panels, large vacuum pumps sucked the fines onto the screens and then scraped off and diverted onto a conveyor then dropped into a centrifuge that spun out most of the water. All water used went to settling ponds. Not a lot of waste.