Remove the fission products from "spent" fuel, store said fission products in casks at a national storage location (not a huge tunnel in the ground....it's not needed) reuse unused fuel. In 300 years high energy gamma fission products will have decayed away. Look, I just saved trillions.
"Spent" fuel IS NOT dangerous for thousands of years, so why are we still looking to build a dump with those requirements? It's fairly common science, really.
So, take those trillions and lets put it towards making the USA the Leader of the next generation nuclear reactor world.