Discussion Manga / DrStone

Not true unfortunately. In the scenario that humans suddenly disappear as they essentially did in this work, there is still a chance a nuclear meltdown could happen and if it does, any one plant would result in tons of radioactive material escaping into the air, water and soil which would cause world wide contamination. Not only that nuclear fuel stored onsite in pools of water would eventually be boiled away and the rods exposed to the air which will burn them. That event would cause the land a few miles around the plant to be contaminated. Furthermore Chemical plants making dangerous chemicals could explode in the absence of electricity which would happen not long after humans disappearance. The result being a very bad time to be alive. Oil refineries can and would explode without any maintenance; Untended Petroleum tanks, Other Chemical plants and Power Plants might poison the earth beneath them though Japan might not have to worry too much on that point since it doesn't have much of any of that. Still the resulting chemical and nuclear damage would still be felt millenia later.

No, there's very little chance of a nuclear meltdown. Once the humans are gone, all nuclear power plants would wind up in emergency shutdown anywhere from a few hours to a few days afterward. There would be a lot of residual heat in the core, but that would dissipate in a matter of weeks. The only way a meltdown could occur in that state is if the control rods either were somehow removed, or if they somehow decayed, leaving the fuel rods intact and in position. Without a moderator, it would require the removal of quite few control rods to begin a nuclear reaction.

If a reactor did melt down, it wouldn't "result in tons of radioactive material escaping into the air, water and soil". It would result in the core melting down (hence why it's called a "meltdown", the core literally melts), and flowing down into a puddle on the floor. Spreading the nuclear material out increases the ratio of surface area to mass, allowing more neutrons to escape, ending the reaction. Sure, that one room would get incredibly hot (both in terms of temperature and in terms of radiation level), but it wouldn't spread much beyond that. Worst case scenario, if it somehow managed to get into the ground water, it might be able to contaminate a few dozen square miles (this in a country that's 150,000 square miles).

You also didn't mention chemical plants, power plants, etc. in your edit, so I don't know why you're bringing them up now, but your estimate of the environmental damage they would do is also vastly overstated. Even if every chemical plant in the world contaminated a hundred square miles around it, that's still a tiny fraction of the Earth's surface. (Edit: Also, mere chemical contamination would only last decades to centuries, depending on the type of plant, not 3,700 years.)

Can you give me a source on your info? Because every article Ive read says something different. Yes many have Nuclear power plants around the world have many fail-safes to ensure any meltdown is extremely unlikely. However this is assuming that the absolute worst scenario does not happen, which is the total absence of external power and any kind of human aid. Which is exactly what happens in the manga. Also saying that every last power plant would go into emergency shutdown without any trouble or human help relies too much on happenstance and every little cog in every power plant for me to believe that. If everything does go right and all the cogs are working that is still assuming that all nuclear power plants are in a state were they can be shutdown. And assuming all that still took place and the reactor is shutdown it can STILL meltdown due to decay heat. Of course many modern plants are also built to contain meltdowns should they occur but all that achieves is turning the entire structure into a timebomb just waiting for a disaster to occur or for parts of the building to decay and break down.

I brought up chemical and power plants since I forgot they existed as well and would also go haywire once mankind disappeared. While some of the chemicals would eventually degrade, there are many others like PFAS that will simply not degrade at all. Lastly you are underestimating the consequences of any of this getting into groundwater. Any of above toxic materials getting into the water is an absolute worst case scenario. Even if you assume the materials wont last forever, there will be a significant die out of animals and maybe plants which in turn will cause problems even millennia later.

Also that's not how meltdowns work.

I don't know what kind of fear-mongering anti-nuclear propaganda articles you've been reading, but you have only to look at the Three Mile Island Accident to get a better picture of what would happen. Long story short, the workers mishandled maintenance of reactor #2, causing a reactor scram. A faulty indicator on the board made the operators think there was too much water in the reactor, so they drained some off, allowing the level to fall enough to expose the top of the core, which resulted in a partial meltdown due to decay heat. (Which reminds me, I'm curious about your definition of "meltdown". You rejected my definition of "When the core melts down", but never provided your own.) End result: a pool of molten uranium in the bottom of the pressure vessel, and the only radiation leak was several days later due to workers panicking over a harmless hydrogen bubble (to be fair to the workers, even the NRC people didn't realize it was harmless at the time, due to the fact that they didn't know nearly as much about nuclear power as we do today).

Not going to lie, I actually, honestly Laughed Out Loud when I read the part about how an emergency shutdown "relies too much on happenstance and every little cog" and "assuming that all nuclear power plants are in a state were they can be shutdown". Shutting down a nuclear reactor involves inserting control rods into the core. That's it. That's all there is to it. Most of the complexity involved in a normal shutdown comes from the fact that operators want to minimize thermal stresses, which can shorten a reactor's useful life, so they shut down slowly. Also, if the reactor shuts off immediately, then other power plants on the grid have to suddenly take up the slack, putting pressure on them as well. Also, a bunch of other things that come from a standpoint of practicality rather than one of safety.

Not to mention that control rods can be moved by gravity just as easy as they can by machines. So, a simple safety system is to attach the rods to their lifting mechanisms by electromagnets (or they can use hydraulics, but it's usually magnets). If external power is lost, the magnets de-energize (or hydraulics de-pressurize), and the rods fall into the core. Now, I don't know for sure that all nuclear plants in Japan have this feature — there's a limit to how much research I'm willing to do for the sake of an internet debate — but, given how long that's been a standard part of commercial reactor design, I'd be willing to bet that they do.

There's also no "ticking time bomb" effect. Nuclear reactors require some form of neutron moderator in order to sustain the reaction. Most use water, because it's a good moderator in itself, and it can also function as a coolant, and as a safety feature (if the water level falls, the reaction rate also falls due to being undermoderated). That water will slowly leak out or evaporate, making it extremely difficult to generate enough heat to trigger a meltdown.

Then, you look at what happened to the environment after the Chernobyl accident. Due to the removal of human activity in the exclusion zone, wildlife is flourishing. Many rare and endangered species are making a comeback in the area. Sure, the high background count is causing a much higher rate of birth defects and physical abnormalities than normal, but they still only affect a small portion of animals, and natural selection ensures the mutations aren't passed down to the next generation.

TL;DR: 1) The odds of even one reactor meltdown is relatively low. 2) Even a reactor did melt down, the odds that it would turn into a Chernobyl-scale disaster are vanishingly small. 3) Even if every single one of Japan's 17 operable nuclear power plants became another Chernobyl, it would only contaminate less than 1/5th of Japan's land area (and that's assuming there's no overlap), and that area would still be teeming with life. 4) I didn't mention this above, but the background count around Chernobyl is already measurably falling. In 3,700 years, you would never know that there was a nuclear accident in that area without some very sensitive instruments.

As far as chemical plants go, yes, there will be a major ecological disaster in the area when they leak. Massive die-offs of plants and animals, some endangered species might go extinct, water poisoned for hundreds of miles around, etc. But the Earth is a pretty big place, and these disasters will be tiny in comparison. As the pollutants disperse, they also become more dilute, reducing their effects. In 3,700 years, you would never know that there was a chemical spill in the area, even with the most sensitive detector you can get.

(Edit: Holy crap does the discussion page mess with links and formatting and such. That's pretty bad.)

Honestly Im really tired of this discussion. Not because Im frustrated with you but because after I read your comment I triple fucking checked with people who actually know more than me, spent HOURS reading every legit article on the subject I can find, every educational video on the subject and scrap of information that would prove you right. And I cant find a single damn thing that does. I would be completely fine with dropping this if you were right but your not right. But since I don't feel like arguing with you anymore can we agree to put this in headscratchers or fridge logic and move on?

Seriously? "I don't feel like arguing with you anymore can we agree that I'm right and move on?" Is that seriously what you're asking me right now?

I'm tired of this discussion as well. Because for all your talk about "HOURS" of research through "legit" articles, you seem to have missed all the information about Three Mile Island, and the Chernobyl Exclusion Zone, and all the other stuff I said.

Look, how about we get someone else to chime in?

I’m working off input from a friend here, but I’d say it would depend on the design of the reactor. Very modern reactors and certain types of liquid metal ones would probably be fine, older ones would most likely not be fine. Modern nuclear reactors are designed to be “walk away safe”, or in other words able to safely shut down even if every human abandoned the controls all at once.

It’s worth remembering, though, that a meltdown is not a nuclear explosion, and that after 3700 years the results of things like this would be essentially academic.

I'd question whether after 3,700 years the leftover radioactivity is enough to deter anyone from going into a given place, but there is a bigger problem with this line of discussion: These kinds of nuclear physics minutiae are totally irrelevant to cataloguing storytelling tropes.

Look. This discussion we are having is being discussed elsewhere as well. While details vary, especially on whether any radiation will be a problem thousands of years later, there is a near consensus that a meltdown (which is not a nuclear explosion as archonspeaks said)would occur in absence of external power and human aid with more than a few saying that all nuclear power plants would meltdown. This is hard to believe but this came from someone who actually works at nuclear power plants so eh. The ones that do say "No" will not definitively say that power plant would never meltdown, saying that it was definitely probable. I agree with what Septimus said, this doesn't truly belong anywhere except in fridge logic or Headscratchers since I cant find anything concrete that says the radiation would last 3000 years. Other facilities of course like Oil plants, chemical plants would definitely explode and contaminate everything, with some of contaminants being more undegradable than plastic. But as far as radiation goes, I don't know and no one else knows either.

You're right, I think we've kind of drifted off topic here.

Your original edit claimed that Japan would be an irradiated wasteland in the future, "thus making the story impossible" (your own words). Now, you're correct in saying that nobody knows for sure what will happen in that situation, since it's obviously never happened before. But that doesn't mean that we know absolutely nothing. Nuclear plants have melted down before, there have been releases of radioactive material, and all these have been studied. And the scenario you originally described is patently false.

Again I ask you, nay, beg you, to read up on the Chernobyl Exclusion Zone. I would put links, but as we saw, the discussion pages do unspeakable things to URLs. I think if you just google "wildlife in chernobyl exclusion zone", it will be an eye-opener.

Note: I have worked at a nuclear power plant. Me. Not "a friend of mine" or "somebody I met once", me personally. So, if "works at nuclear power plants" (again, your own words) is your criteria for an expert, then, yeah, by that definition, I'm an expert.

Putting aside that I'm not sure any one trope is worth this many walls of text, given we're arguing actual physics here, shouldn't there be citable sources that can be shared to verify one viewpoint or another.

The only such link at all is the one about three mile island, though on closer inspection I'm seeing more references than I initially thought, in light of how discussions screw up links.

^ I have to admit, one of my personal berserk buttons is extremism in any form. Yes, I reacted pretty strongly to Hutar's "OMG nuclear power is so super dangerous it could sterilize the planet for millennia" rhetoric, but in my defense, I'd react just as strongly to "OMG nuclear power is absolutely 100% safe and will solve all our problems oh and it can raise the dead" rhetoric.

So, I apologize for the enormous walls of text. I shall bow out of this discussion (unless someone wants to ask me something) and allow the community and/or moderators to decide.

To be fair, I didn't mean to imply that that the world in the future would be dead and lifeless. And Yes I have read up on Chernoybl exclusion zone extensively. What I meant to imply was that the overall background radiation MAY be much higher than it is normally is now. So much higher that while every other creature would have adapted to it already including the humans who survived the disaster, the ones emerging from their stone prisons would have a harder time of it. That's of course not to mention all the undegradable materials left over like PFAS and plastic which as it turns out does not decompose but breaks down into micro-plastics which are just as bad as plastic if not worse.

I don't think it qualifies for Artistic License anything if you attach the caveat "if someone else unforeseen happened, then theoretically it could've been different."