This is the final report on the conceptual process design as part of the project on The Development, Testing, and Manufacture of an Ultra-Clean Coal/Water Mixture (UCCWM) conducted under sponsorship of Morgantown Energy Technology Center of the US Department of Energy. The objective of the conceptual process design is to develop the cost production of an ultra-clean coal/water mixture based upon its specification of less than 1% ash, less than 44 micron top particle size with minimum 60% coal loading. To meet the required specifications, Elkhorn seam coal, one of the lowest inherent ash coals, which is produced in the Eastern Kentucky area, was selected and cleaned by a two-stage physical process: (a) heavy media washer near 1.30 specific gravity separation, and (b) column flotation after grinding the heavy media washer product by a ball mill to -100 mesh. In order to micronize the coal/water mixture, the flotation product was processed through a stirred ball mill. The capacity basis of the coal cleaning and slurry manufacturing plant was to supply the UCCWM fuel for operating a typical 100 MW gas turbine continuously. The raw coal feed rate to the cleaning plant was 300 tons per hour and the final UCCWM fuel production was 70 tons per hour by dry coal basis. In addition to that, two by-products, boiler grade CWM and 1/4 inch x 0 coal, are obtained. Economic analysis showed that the total capital cost for the plan was $30,614,000 and the final gas turbine grade CWM cost estimate was $3.96/MBTU in 1984 dollars F.O.B. plant. If we assume that the potential market for the fuel is located in the Northeastern United States, the delivered fuel is estimated to be $5.44/MBTU. 2 references, 1 figure, 4 tables.