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lisper

Gotta love the conclusion:

"In summary, it is preferable to not eat spent nuclear fuel."

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It was interesting to see that it truly was only "preferable" and not "mandatory" or "this will kill you" IMO

That's the interesting thing: it's not really very hazardous, but it is awfully annoying.

And not even "annoying due to health issues" but instead "annoying because it'll make you leave your job if you work in a field with dosage limits" and "annoying because you'll be setting off the radiation detectors when leaving the exclusion zone"

To be fair, it has had several decades to decay, and the most dangerous radionuclides are the ones with short half-lives and thus high output. It's pretty amazing that it's still that dangerous given it's had over 30 years to decay.

And it’s really tiny. Lots of serious poisons would be harmless at that dose.

Noob question, if it decays so quickly, how come there's so much of it around this late in the Earth's history? Or was it created only decades ago, by artificial means?

Some things decay quickly and some very slowly, forming a sort of chain where the events might happen fast-slow-fast-fast-superfast-superslow-slow-fast-medium-fast-slow, or something like that.

So these fast-decaying things disappear quickly but are also being constantly created by things spontaneously decaying into them. The point of a nuclear reactor is to increase the overall rates of decay, so you end up with disproportionately large amounts of the short-lived isotopes as opposed to what you would find in nature.

https://en.wikipedia.org/wiki/Decay_chain

If you scroll down you see thorium series, neptunium series, uranium series, and so on. You can see the half-life at each step.

The short answer is, we created it. The half-life of Uranium 235 is 700 million years, so there's plenty of it around. When you bring a bunch of U235 together and cause it to undergo fission, it creates a bunch of the shorter-lived stuff as a decay product. Especially when a reactor melts down; you get a lot more of the stuff you didn't want, in a much more uncontrolled manner.

Sort of not really? There's some specifics to this hypothetical situation that minimize it's effects. In this scenario you're consuming a solid piece of radioactive material that passes through your body and is quickly expelled. When you have a Chernobyl type disaster or a nuclear explosion the radioactive material is atomized and spreads through the air. As you breath in the radioactive particles they pass directly into your blood stream.

This is how you know it was written by an engineer. The executive summary is at the bottom.

Now you tell me! What are you going to tell me next, that yellowcake isn't made from flour?

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