It could be reprocessed for use in a breeder reactor, but breeders are not attractive at present or foreseeable uranium prices. They make the expensive part of nuclear power (capital costs) even more expensive to save money on the part that doesn't cost much at all (making fuel from mined uranium). If nuclear power expanded drastically then breeders might be more affordable than exploiting really marginal uranium sources, but otherwise they make the economics of nuclear power worse.