Consider this page by the Virtual Nuclear Tourist. It shows the costs associated with fission generation as being about the same as for coal.
This does not take into account the costs associated with the environmental damage from mining the coal, let alone the costs associated with the increased level of mercury in the ecosystem. While the nuclear fission plant produces concentrated waste products, the coal plant spews them throughout the environment.
This Scitizen article argues that renewable sources are enough to avoid using either coal or nuclear fission. My feeling is that this may have been true had we gotten started earlier, but that we don't have the time left to implement these alternatives. I think that we have to proceed with a buildout of fission plants to help us replace oil and coal power generation.
--SCC
