[numpad0]

"High level nuclear waste" is such a weird idea once you take a bit of in depth look at nuclear technology. It's just fuel. Just nuclear material. No need to "manage for extremely long periods of time". Only requiring more sophisticated Fast Neutron technology to be used, and if used, provide practically unlimited supply of electricity and nuclear material to a nation.

The reason as to why "safe storage of nuclear waste" is a problem lies in the last part: unlimited supply of nuclear material. Completely destroys national security for everyone. Without that part the problem reduces to just engineering challenges of building and running some Sodium cooled Fast Neutron reactors.