Maybe this is a dumb question, but why can't nuclear waste be diluted? You get U-235 though enrichment of naturally occurring uranium. Why is there no way to reverse this process?
It makes more sense to just put it all in a deep hole, only it's hard to make a really stable hole things won't leak out of.
I hope to god the goal of any remediation is in the service of conserving the site and the artifacts for their historical value. If Marie Curie's notebooks eventually end up encased in concrete somewhere "because they're contaminated"--
They are in fact contaminated, so they are kept in lead lined boxes:
https://www.csmonitor.com/Technology/Horizons/2011/1107/Mari...