In addition to that, it is a highly reactive and toxic heavy metal, even without radioactivity as part of the equation.
The problem is not the small amounts, but a concentration far beyond what would normally occur in nature. It may not take 10,000 years, either, the ice sheets were pretty much gone here in just a couple of thousand.
I agree with the concept that processing spent fuel to get more fuel does address the waste problem--it is the equivalent of recycling.
As I said, I am not against nuclear power. Processing 'spent' fuel currently in questionable storage areas is a good idea--more fuel, less waste to inter. In the short term this is a solution, but it is a remedy, and not a cure.
These are problems which need to be addressed, especially if we are going to expand our capability.
"Plutonium is slower to decay, and thus less active per microgram, but if enough is assembled, it is remains dangerous longer."
But we were talking about them being embedded with other material in well-sealed canisters in Yucca. It's not highly concentrated and in a stable environment. I dont see a scenario of the canisters being compromise as credible. These are huge thick-walled sealed things that are immune to huge pressure and temperature impacts, let alone what can happen inside a cold, dry mountain.