That "waste" is fuel in a breeder reactor (or other advanced reactor designs). Current (ancient) reactor designs only recover a very small amount of the usable

That "waste" is fuel in a breeder reactor (or other advanced reactor designs). Current (ancient) reactor designs only recover a very small amount of the usable energy (something like ~3% of the U235, if I remember correctly?). Worrying about disposing of "spent" fuel out of fear for of it's current physical properties (radiation) is like worrying where we should store the "waste" 97% of the gasoline remaining in your car because you only allow an engine design capable of using 3%. Waste has never[1] been a technical problem. The people creating the problem of waste are the people that push irrational fears about any new reactor designs that would solve the problem. [1] a small fraction will always remain as waste, but that is something we have some control over by choosing the nuclear decay chain=, and it would still be a few percent of current reactor output. Even with current designs, the massive gain in energy density makes the current amount of waste trivial compared to the fly ash waste of coal power. Coal is worse even if you only consider radiation, and coal waste also contains heavy metals and other chemical waste that doesn't got away even with a long half life.