The work discussed in this report centered around evaluation of the atomization, ignition, and combustion characteristics of several coal slurry fuels under conditions representative of medium size and speed commercial diesel engines typically used in railroad locomotives and stationary prime mover, electrical generation, and cogeneration applications. This effort was aimed at defining the near-term potential for operating coal-fueled medium speed diesel engines and identifying the technical areas limiting slurry fuel use in conventional engine designs. In the most cursory sense, this program was directed toward assessment of the operability and performance characteristics of conventional medium speed diesel engines utilizing coal/water slurry fuels. Again, in a cursory sense, the general conclusion of the program is that the conventional engine is unsuited to the utilization of coal/water slurry fuels and that improvements must be implemented in the following areas: injection system, combustion chamber materials, lubrication system, and ignition. In addition to these general conclusions, more specific information was developed in the following three specific areas: ignition, fuel injection, and fuel properties. 23 refs., 63 figs., 17 tabs.