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Let's break down the problem you've stated.

> managing nuclear wastes for thousands of years

There's a fun way to think about this: the more dangerous the isotopes in terms of radiation, the faster it becomes safer. That radiation is the isotope breaking down into something else, something more stable. For the most dangerous waste, the stuff that has proliferation risks, in a few decades it's not nearly as dangerous. So "thousands of years" is a popular misunderstanding, in my view.

> There is such a woeful global record of adequate safety measures

There have been a small number of incidents- Chernobyl and Fukishima primarily- but that mostly boils down to poor initial designs or choices for locations. No CANDU[0]-based reactor design has ever had a dangerous safety incident.

I know I'm trying to convince you of something you don't agree with, but give this link[1] a chance. It has a lot of answers to some of your oppositions- maybe you agree with them, maybe you don't, but I think it's well written at least.

[0] https://en.wikipedia.org/wiki/CANDU_reactor

[1] https://www.world-nuclear.org/information-library/nuclear-fu...



> So "thousands of years" is a popular misunderstanding, in my view.

"Thousands of years" comes from the half life of Plutonium-239, which is 24,000 years.

Pu-239 isn't unusually dangerous for an isotope. It's chemically toxic and somewhat radioactive but so is tons of stuff. The biggest problem with it is that you can make nuclear weapons from it.

Most commercial reactors make both Pu-239 and Pu-240. They're infeasible to separate (harder than separating U-235 from natural uranium) and enough Pu-240 makes the plutonium unsuitable for weapons.

But Pu-240 has a shorter half life than Pu-239. So if you take the plutonium out of a legacy reactor and bury it in the ground for a long time, it turns into weapons-grade plutonium. Burying it in the ground is very stupid because then you have to guard it for tens of thousands of years to keep anyone from going in and taking it to make nuclear weapons from.

But that ship has sailed. We have a half century of the stuff already. Half again as much or not makes no difference, we need a solution for what do with what we already have regardless of whether we make any more.

The solution is that newer reactors can use plutonium as fuel, which permanently eliminates it. So far from nuclear waste being a reason not to build newer reactors, it's the reason we should, so we can get rid of what we already have before it becomes suitable for weapons.


239Pu's radiotoxicity vastly exceeds its chemical toxicity.


As an alpha emitter with a long half life?




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