If you just divide the number of meltdowns (5) with the number of active power reactors in the world (449) we learn that statistically 1% of reactors will have a core meltdown.
https://en.wikipedia.org/wiki/List_of_nuclear_power_accident...
The term "meltdown" means the core has melted. I don't know where you got the number "5" from, because it's not the number of meltdowns globally (there have been a lot, almost all of them contained) nor the number of accidents with widespread consequences (2: Chernobyl and Fukushima).
During tests of felled wild boar in early 2019[0][1] showed that around 70% of the ones from Gästrikland (the region in Sweden that was hit hardest from the Chernobyl fallout) contained caesium-137 concentrations way above the 1500 Bq/kg guidelines, above which the animal is considered unsellable, ungiftable, and meat from such animals, for private use, should only be consumed at most a few times a month (up to 3000 Bq/kg), or not at all (>10 000 Bq/kg).
Several animals (unclear how many) had caesium concentrations of over 40 000 Bq/kg, so there's a huge variation. Cannot find more exact figures than that.
There are some interesting updated figures here, but not as big a study: https://krets.jagareforbundet.se/gavlesodra/cesiumrapport/
There's a debate[2][3] about who should pay for testing these animals, because any animal above 1500 Bq/kg should be destroyed, and radioactivity tests are really expensive. Hunters want the government to pay. The government wants none of it. As it looks right now, wild boar hunting in these regions for the purpose of selling the meat is not economically feasible. This might change [4] (taxpayers will foot the bill).
It's not only in Gävleborg/Gästrikland either. This map is from the Swedish Radiation Safety Authority's tests from 2018, mostly south of the really problematic areas: https://www.stralsakerhetsmyndigheten.se/contentassets/90ef7...
Sources: [0]: https://www.svt.se/nyheter/lokalt/gavleborg/mer-an-vartannat... [1]: https://www.livsmedelsverket.se/livsmedel-och-innehall/oonsk... [2]https://www.svt.se/nyheter/lokalt/gavleborg/mer-an-vartannat... [3]: https://www.thelocal.se/20191222/should-sweden-foot-the-bill... [4]: https://www.svt.se/nyheter/lokalt/gavleborg/staten-kan-bekos...
If you look at the sources more closely, you'll see the "70%" figure was the number of wild boars that have measurably higher levels of radioactivity. Not the number above the limit.
This has been a big thing for the Hunters association since the limits are very low and fallout was very localized, hunters in some areas are very much affected since they could not sell the meat.
It's a pity, since even Livsmedelsverket themselves say 1.5 kBq/kg is safe to eat several times a month[1]. The limits are set very low. Granted, they state above 10 kBq/kg should not be eaten, but there were very few animals above that value.
[1] https://www.livsmedelsverket.se/livsmedel-och-innehall/oonsk...
100% of animals (only 8, because of limited funding for testing) tested in 2020 by the Southern Hunter's Circle in Gävle (that embedded link in my post) in were over 1500 Bq/kg, with an average of 6263 Bq/kg.
SSI/Livsmedelsverkets's irradiation limits are "low" (your opinion) for a reason, because we just don't really know much about the long-term effects. These limits have not been changed since 1986 in Sweden, but what I do know is that they're 3 times higher than, for instance, in Germany, which sets the limit at 600 Bq/kg. The US: 370 Bq/kg. Japan (implemented in 2012 after the Fukushima incident, because there were no prior legal binding limits): 100 Bq/kg. Yeah, what a "pity", as you say.
The original post was not "preposterous".
To put some perspective into it, an average banana contains about 150 Bq/kg from radioactive K-40[1]. K-40 is pretty comparable to Cs-137 biologically but nobody even considers limiting the amount of banana eaten. Bananas are regularly given to infants (which are the population most vulnerable to radiation damage) from six months of age, but nobody bats an eye, because 150 Bq/kg gives you such an extremely low dose.
Wild boar is safe to hunt and eat in the entire country, so yes I'd say your original statement was preposterous. If I was a very prolific hunter and my staple food was boar, I'd be concerned if I lived in one of those areas, but not otherwise.
But then again, in Sweden we live in houses built on granite bedrock with walls made from radioactive lightweight concrete. The radon gas emitted from them gives you a dose magnitudes larger than eating wild boar, mushrooms and berries your entire life.
Think about fat tails and asymmetric risk. If you read in the newspaper next year: "Hundred thousand people dead/displaced due to power plant accident" - more likely to be coal or nuclear?
Coal kills slowly but is the power source that's killed most people over time. Nuclear has killed the fewest by far.
> Think about fat tails and asymmetric risk. If you read in the newspaper next year: "Hundred thousand people dead/displaced due to power plant accident" - more likely to be coal or nuclear?
What's your evaluation of the probability of this event ? Without putting figures in the equation, I could also ask you in the same way to think about this event : if you read in the newspaper next year: "Billions of people dead/displaced due to one in a thousands year drought, leading to global famine" - more likely to be coal or nuclear?
Nuclear. Naive probability matters relatively little here. The risk of coal plants due to CO2 is a thin-tailed long term risk. No single coal plant will ever cause a headline (or an event) like this. Thin-tailed long-term risks can be mitigated and planned for and the result is always a sum of many smaller choices (albeit global warming is an existential risk for sure!).
Nuclear is different. 99,999% of time it's cheaper and cleaner than coal. Doesn't matter. The tail-risk is what matters and that's also, why (conventional) nuclear can't ever be economically competitive against any other power source without direct or indirect subsidies (there is no insurance that will insure a nuclear power plant).
Highly recommend Taleb`s paper on fat-tailedness [1].
https://en.wikipedia.org/wiki/Harspr%C3%A5nget_hydroelectric...
No large chemical industry handlng dangerous chemicals, in developed countries or otherwise, has an insurance large enough to pay for huge expensive spills. That's why the company usually defaults when it happens and leaves the cleanup for the government later on. This has happened on numerous occations in the US, Europe, and over here in Sweden.