Complete Uranium processing plant, contained within a 4-roboport city block and designed to minimize excess production of any single byproduct. Almost exclusively belt-based except for fuel cell distribution and depleted fuel cell reprocessing, although both of these can easily be put on belts without significantly changing the design. Includes audio warnings for low-accumulator power and for excess U-235 production (although that's pretty unlikely in this configuration). Capacity: easily supports my 8GW factory. Can probably support up to 16GW of nuclear power plants.