And fill them with what? How much nuclear waste are you expecting? At most you would need a few Yucca Mountain size facilities per century, because you need to reprocess at some point. There would probably be a few other facilities in other countries.

Bad idea anyway, you want geological stability and either low moisture or clay sealing. There are several good places, that are more than big enough, but putting waste everywhere would be stupid. At that point just store in dry casks like we do now.