well, producing it is clean. The waste of course is a concern, that we havent figured out what to do with yet.
There are some solution glimpses about that. But the problem is always that it is cheaper to produce standart radioactive waste than to deal with it.
A few countries, like Rusia, Canada and France have a special kind of reactors, that have been in an experimental state for at least a decade, they are called "Fast Breeding Reactors". They are more expensive than ordinary ones, but they are an interesting path to a solution to the nuclear waste problem.
