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>Modern fission plants are totally safe. Nuclear waste is basically a non-problem, especially with the most recent technology

Please elaborate on both. And I think we can all agree there's no such thing as totally safe, only risk management.



Gen2, even with weird designs (so Fukushima included) are individually safer than any coal plant ever built, and the whole generation will kill less people, even counting those dying in a shameful, unprepared evacuation, that the new "clean coal" plants (with flue gas discharge) built in the western world since the 2000s. Not taking into account the GHG emissions. Number of death/GW is in the favor of nuclear for any power station, even when counting dislodged people as "dead" (in this case, hydro is actually the 2nd most deadly)

For the nuclear wast beeing a non-problem: i don't agree, but i understand where he is coming from.

There is basically 3 type of nuclear waste: low-activity waste is waste that we could ignore, and the most present. radioactivity levels are what is find in granitic area. Often indirectly contaminated materials, or very long-lived isotope (radioactive decay is long, the the material is not very radioactive). It can still be dangerous and create radon gas if poorly stored (as do caves in granitic areas). We have no good answer to that. Maybe separate long=lived isotopes from the rest, store it, and reuse the contaminated materials after waiting a dozen years, mixing it with new cement or something.

intermediate-activity waste: still extremely dangerous, its often contaminated material (filter, pipes), or active (and dangerous) isotopes, with a half-life of up 500 years (i think the most present have an half-life of 200 years, and you need 10 cycles basically to be rid of it). Those are not direct fission byproduct (i don't think so, i don't remember exactly, maybe a small number is?).

High-activity waste: This is the real dangerous stuff. Those can stay hot for years. There is to kind:

- direct fission byproducts. Some degrade not in stable isotopes, but in the intermediate-activity waste, so even with a short half-life, they take as long as the intermediate ones to get rid of (since they degrade into it. If i'm over-explaining, sorry). Some degrade into stable heavy metals that also poison the environment, in a different way.

- transuranic elements. The graphite from Chernobyl could be counted in this category? (not sure, if an expert is here, can you infirm this?). I do not exactly understand this category, but its basically elements from the reactor core that are not fission products.

The reason why GP said "Nuclear waste is basically a non-problem" might be because we are able to re-use some the fission products, and to deactivate the rest. Both technologies are at an experimental stage, the first one could be in commercial use in the decade if China doesn't fail. And since the fission product decay is what's create the most troublesome waste (half-life between 100 and 500 years mean the wast stay dangerous for between 1000 and 5000 years), its a "non-problem".

I don't have the material on hand, i learned that in 2019. i could find it again if you wanted (probably mostly be in French, sorry), and to be fair, i might have oversimplified things i did not understand in the first place.




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