Uranium mining, milling, conversion, enrichment and fuel fabrication are all not free.
Because of protection from radioactive radiation, you have higher costs handling anything in a nuclear reactor compared to a coal plant. Then you have the issue of runaway nuclear reactions, hydrogen buildup etc.
By "free" I mean that you need so little fuel over the lifetime of the reactor the cost is negligible compared to all the other extensive costs of building and managing the plant.
Because of protection from radioactive radiation, you have higher costs handling anything in a nuclear reactor compared to a coal plant. Then you have the issue of runaway nuclear reactions, hydrogen buildup etc.