Dramatic escalation in Japan (Fukushima Nuke Plant)
world-nuclear-news.org
world-nuclear-news.org
Conclusions at any stage of this crisis have been premature, but HN seems to want a heavy dose of finality to a crisis that isn't even over yet. Apparently people don't want it to be a big deal, but it's slowly turning into a big deal. It just is. Instead of big essays and conclusions about how the powers-that-be have it under control complete with inaccurate depictions of how a reactor works, why don't we focus on facts?
With that in mind, we do not know how bad it is. Anyone who says they do is lying to you. It isn't over, and it is a basic fact of logic that we will not be able to reflect on how bad this is or was until it is over.
At the risk of a neener-neener I told you so, I presented some of this viewpoint[2] on the self-aggrandizing risk management Ph.D.'s everything's fine piece, but my viewpoint was drowned out by people wanting to rush to a conclusion so they can put the crisis out of sight and out of mind.
[1]: http://edition.cnn.com/2003/WORLD/asiapcf/east/06/17/tokyo.s...
It's inconceivable (cue sound clip from Princess Bride) to most of us that extremely extensive and effective contingency plans are not in place.
The nuclear risk is obvious, and so any nuclear construction's main emphasis must be on handling all possible contingencies... right?
If Fukushima does end up being a "Big Deal" that is going to forcibly shift the world view of many many engineers and hackers. It will represent a piece of data that is fundamentally at odds with our view of the world.
The facts will eventually win out, but for the short term, it is necessary that we go through these cycles of disbelief and then shock. Because that's just reality.
I will be shocked if Fukushima causes serious harm to humans because until now it has been inconceivable to me that people making nuke plants could possibly underestimate the risks. If my inaccurate beliefs are shattered by the harsh reality of nuclear related deaths then... that's just how it will have to be. I'll have to eat my hat. I'm not looking forward to it.
In the meantime I have to go with what I know. Which is that this should not be an issue that threatens human life.
Sadly that rarely changes anyones mind.
Any guess as to who understands the science better? But then, its not about science is it? And its certainly not about facts.
The piece that rationalist engineers (I am one of them) tend to gloss over is that the public has historically been lied to, by experts about the dangers and difficulties of nuclear power -- all nuclear technology, really. X rays for shoe sizing. Atmospheric weapons tests. Ed Teller. The downside to accidents is large, and there's not much trust anymore. Some, but not much.
These are the facts that are perhaps engaging people's fears.
Given this history, for some people, the bank of "expert credibility" is overdrawn already. The classic nerd technique of argument from expertise is ineffective.
Seriously if they won't listen to experts (assuming that we can agree on whom the experts are), that is perhaps the best argument against democracy that I have ever heard.
It's an argument against lying in the first place.
Ah, the glorious ad hominem. Here's one of your recent comments.
"In terms of real disasters, when measured in human deaths, [chernobyl] are tiny footnotes in history, statistically irrelevant."
Ironic isn't it, given my previous comment?
Or this,
"just as several decades of extensive use of nuclear power generation with practically no deaths"
What is the scientific definition of "several", or better yet, "practically no deaths"?
That actually hurt me physically to read.
Take Chernobyl. All of those kids that have developed and will develop thyroid cancer, the firefighters that knowingly sacrificed themselves to get the fire out (thereby directly saving more lives), the plant workers who killed themselves in order to minimize the effects, the liquidation workers who contracted cancer in the process of building the sarcophagus, and the babies being born -- even today! -- in the surrounding area prematurely and dying before even being able to comprehend where they are (which some doctors from that region blame on Chernobyl). Yeah, those deaths aren't practical at all. How can you be so obtuse?
Nothing wrenches my gut more than a child dying before being able to speak a single word. I'm actually tearing up that you dismiss such things as impractical statistically, in order to further your argument that us laymen have no idea what we're talking about when it comes to nuclear episodes.
You take relative figures and turn them into an absolute. In multiple comments, you have denied that nuclear power has ever had a disaster, and that "practically" anybody has died (whatever the hell that means). You might believe strongly in nuclear power, but you cannot erase or modify history.
Nuclear power is safe. It can also go horribly wrong, and we learned a lot from Chernobyl. Why does it have to be polar with you? It can be both.
> And its certainly not about facts.
Such cruel irony.
Yeah, that always gets to me, too. And it is also funny how lots of these people try to downplay the effects of the Chernobyl disaster, if that's even possible. When it comes to the number of casualties they hurry up in bringing up the 4,000 mentioned in the IAEA report, which is like asking Dick Cheney or Donald Rumsfeld of writing up about the effects of the Iraq mess.
Just today I was reading about how in one of counties of Romania (of which I am a citizen) the number of deaths caused by cancer is double the number of deaths caused by TBC (which used to be the number one killer before 1986) or diabetes. One might argue that this may be caused by a sudden change in the the conditions of living or anything related, but I can assure you that's not the case (if anything, heart-related deaths should have been on the number one spot). Of course, you won't see these cancer-related deaths taken into account in any of IAEA's reports.
I also have some sort of personal emotional involvement in all this, as one of my childhood playmates and best-friends died of leukemia in 1990. He was 5 when Chernobyl happened, but of course no-one can link his death to that disaster, can it? It doesn't matter that I can't even remember one case of my parents telling me about kids dying of cancer in the '50s or the '60s, because that just didn't happen (although child mortality was way higher back then). It all miraculously started to happen after Chernobyl.
I wouldn't liken IAEA to Dick and Bush... It is the only credible international organisation assessing effects of nuclear energy and proliferation.
I think IAEA does superb job, unfortunately Japan haven't been very cooperative with them thus far.
So we need to have responsible, transparent and safe nuclear power, and IAEA is the only organisation that tries to ensure that on a global level, IMHO.
What happen in Chernobyl, while bad, cannot happen at these plants because we build them with the security measures that the communists should have built but didn't.
As for the radiation, normal power plants produce more every year than was released here (at least until yesterday).
And the number of people who died as a result of the quake is houndred of times higher than those who may die as a result of the radiation.
That reminds me of all the bragging about how the Titanic was "virtually unsinkable".
Also, I'm not sure what you define as "failsafes", but the conventional measurement is number of containment levels. This reactor had 3, while I believe more modern reactors have 4.
Nature's effect is finite and measurable... earthquakes are easily predictable in the long term... the terrible cost of radiation leak is easily predictable.
Like most other human efforts, the goal posts are pretty clear. Make nuke plants stronger than the strongest that nature is capable of producing.
A tsunami + earthquake in japan is not a surprise to anyone.
What is a surprise is that the people running the reactor consider it a surprise.
I wonder where "8.2" came from in the engineering spec. and whether shooting for the ability to withstand a quake somewhere in the neighborhood of, say, the 10th largest is the right target. Maybe "the largest + 200%" is a better place to start? Of course, it costs more money.
but that's not the fault of the plant's designers
But it is a totally avoidable error. Not the plant's designers error, but a human error nonetheless. Why are we limiting our concerns over human error to just the people responsible for the original design? Surely there were organizations/contractors involved in developing replacement generators. Surely there are current plant safety and maintenance directors. Surely there is a complete nuclear regulatory agency.
It is also likely that the money could be better spend elsewhere (that is, it could same more lives) such as in improving road safety or to hire more police officers.
Consider two possibilities.
One: design the reactor so that a magnitude-9 quake leaves it completely undamaged. Let's say that makes it cost $4B instead of $2B.
Two: design the reactor so that a magnitude-8.2 quake leaves it completely undamaged and a magnitude-9 quake (which might affect it, let's say, once per 200 years on average) makes it fail in a way that takes 100 lives and requires it to be completely rebuilt (to the same spec, let's say) at a cost of $2B.
Cost of option 1: $4B now. Nothing more. Cost of option 2: $2B now. $2B and 100 lives in another 200 years.
Suppose your discount parameter is 0.5% per year (much, much lower than just about any real person or institution uses). Then $2B + 100 lives in 200 years = $740M + 37 lives now.
Can you save 37 lives for $260M? Why yes, you can. Far more than 37 lives, in fact. If you do anything reasonable with $260M you may well save more than 37 lives just by (say) making everyone a little better off. (Wealth correlates with health.)
Therefore, option 2 is probably better.
Turning from hypothetical examples to the real world: $2B/$4B is probably an underestimate (in which case, the advantage of option 2 over option 1 is greater) and 100 lives is probably an overestimate (in which case, again the advantage of option 2 is greater).
On the other hand, the earthquake happened improbably early in the life of the plant. It is not an error to do things that work out well in almost all cases but badly when you get unlucky, when the alternative is something that works out (relatively) badly most of the time but well when you get unlucky.
For the record, I wouldn't agree that all the nuclear power plant dangers have been solved, but they're a hell of a lot safer than most of the day-to-day activities most people engage in, and certainly safer (and cleaner!) than more prevalent electricity-generation schemes in use.
If only that was the only spectacular engineering failure.
Unfortunately, history is littered with them: from Bhopal to Exxon to BP to the Hindenburg, and many many more.
For some more examples, see:
https://secure.wikimedia.org/wikipedia/en/wiki/List_of_accid...
This belief is basically it's own logical fallacy; the idea that because someone has figured out a theoretical solution to a problem, the issue is moot. I feel like I've posted this previously, but I can't find now so maybe not.
How many times are you going to hear:
"The issues were easily avoidable with proper upgrades, but it was decided that the cost of upgrading the plant was not justified given the low probability of an 8.9 earthquake"
:\
And that decision may very well have been correct. If I don't buy a lottery ticket but the numbers I would have picked come up, that doesn't mean I made a mistake.
not a good decision
If anything, you are buying lottery tickets with other people's money and are not winning.
four different reactors
an earthquake
followed by a tsunami
followed by loss of electricity for the emergency pumps
followed by parts of the plant blowing up
followed by tons of dust getting in the way
followed by possibly more aftershocks
followed by possibly more tsunamis
followed by possible injuries to the personnel needed to run these operations
considering other equipment can break down
considering political pressures to make certain decisions
considering some of the physics/chemistry here may be entirely novel
...
There is no kill switch, if they had a "kill switch" and executed it right now, you'd be condemning all the reactors to meltdowns, and you'd be condemning the US Western Coast to dangerous levels of radiation.
The content of the fuel rods take DAYS to become non-radioactive enough for them to not need to be cooled constantly. The very problem that's occuring now is occuring because either the radioactive cesium and iodine is either at risk of not being cooled which will lead to a meltdown and release of them into the atmosphere, or a containment breach with largely the same impacts.
I'm not overly familiar with this specific reactor design; but usually what happens is they seal the containment as the core melts, flooding the sump (where the slag would collect) with water to cool it down.
Right now they are trying to avoid that because a) there is always a risk of radiation leak from the containment and b) because the cleanup bill would catch quite a few more zeroes. The point is; meltdown is the final failure scenario, if they get to it, well, they get to it. But there is no fallback if something goes wrong at that point; so it is potentially better to try and control it at this stage, while you still have a fallback to implement.
Please don't be overly dramatic ("and you'd be condemning the US Western Coast to dangerous levels of radiation"); this is a bad situation. But at the moment there does not appear to be a major risk to the US Western Coast. As you say, best not to comment in too much depth if you don't know the details.
What do you think is failing and is the entire cause for all of this concern. The fallback system is pumping water into the reactor to keep it cool. Those are the systems that have been failing and have failed (during the explosions/fires) and have caused the (temporary-ish) meltdowns in the last few days.
A full meltdown has the potential to release a significant amount of radiation. A full meltdown increases in possibility as the reactors become harder to control and cool due to explosions and containment failure. It probably doesn't pose a significant risk to CA, but they will receive some radiation if it were actually to experience complete failure.
Meltdown isn't binary. They're experiencing meltdown right now. By definition. That's what the release of radioactive material is. The question is, can they keep it under relative control and prevent further exposure of the still proceeding fuel rods.
Not really; in this case "meltdown" refers to the actual process of core melting, it is not entirely clear but it does not appear much or any of the cores have melted. Certainly not to the stage I would refer to as a meltdown. They are still in a "struggling to cool it down" stage.
The release of radioactive material is not equatable to a meltdown - all manner of things can lead to such a release, meltdown is just one of them.
If they actually have a full core melt (to the point it drops out of the reactor vessel into the dry well), yes, the risk of release of radioactive material is heightened. But probably not to the level you envision, and it is certainly not a case of "if it melts it's game over".
Explosions within the reactor shell are extremely unlikely, even in the event of a core meltdown, because the system is specifically designed to stop such an event occurring (which is one reason it has not so far happened :)).
Note; containment failure has not occurred, as far as we know, at any stage. The reactors are not being "controlled", the process is stopping by itself. The reactors simply have to be kept cool while that happens.
What do you think is failing and is the entire cause for all of this concern.
There is a different system in such a case (or, rather, a different approach). Essentially they just flood it with water.
With the best will in the world; it is worth reading some of the more technical explanations rather than just the media. They explain the process and the issues much better - even Wikipedia has reasonable material (and is at least a place to start with links)
QUOTE: "A meltdown occurs when a severe failure of a nuclear power plant system prevents proper cooling of the reactor core, to the extent that the nuclear fuel assemblies overheat and melt, either partially or completely"
That has occurred. That's not in dispute, unless I'm just completely 100% off base here. A quick Google search reveals that fuel rods in both reactors were not only uncovered by water at various points, but were also "exposed" which I presume to be through a containment failure, AND there are numerous reports that the parts of the rods have in fact melted.
As I said earlier, this constitutes a meltdown and greatly increases the severity and danger of the problem at hand. It's not a total meltdown, I already "disclaimered" that repeatedly. Those rods melting pose a large risk to containment efforts. If they melt, they can escape much more easily and that means radiation exposure on a much greater level, even if only for workers at the plant.
Whilst mostly you're correct, there are some fundamental problems with what you are saying.
It's definitely stretching the definition of a meltdown to refer to this event as such. It's still pretty much unknown if any melting has occurred, and to what extent it has done. Generally a meltdown is as I described it; where the situation is unrecoverable with the standard cooling and you are facing the situation of simple containment.
I suppose technically this could be seen as a partial meltdown; but the truth is that this situation is at the very edge of the margin for such a problem. A meltdown is not a binary thing, but in this case it is not really a meltdown, and that was my main point.
Right now it is absolutely recoverable, and based on the latest data #1 and #3 reactors will be fine from this point on. Certainly if they survive the next couple of days it will all be fine.
but were also "exposed" which I presume to be through a containment failure
No. If this were the case there would be a much serious issue :) It simply means the coolant level dropped so far that they were exposed to the air inside the container.
If they melt, they can escape much more easily and that means radiation exposure on a much greater level, even if only for workers at the plant.
Potentially... but bear in mind that radiation expulsion so far is relatively unrelated to the core; the radiation released so far is included in the steam that is being vented (and then the explosions push it right out). In a proper meltdown situation the risk is that an explosion releases actual core material into the wild, that would be a magnitude worse than the current situation.
At the moment I don't believe the rods are melting, they are being successfully cooled (and for the most part have been).
That hasn't helped, though, because a nuclear reactor takes months/years to become "safe" (depending on exactly what you measure and consider safe)
Perhaps what you mean is "hasn't made the impact of a magnitude-9 earthquake and tsunami zero". Honestly, I can't see that that's a reasonable thing to ask for.
The poster clearly thought that a kill switch would be some kind of magic button that would turn everything off and "make it safe". I'm pointing out that nuclear power stations don't work like that.
Clearly, it is a much better situation now than if they had been going when the tsunami hit.
They were unlucky that the tsunami was slightly worse than they had planned for, which washed away the diesel backup generators. Backups for those generators were quickly brought in, though.
OTOH, they have been very lucky that no aftershocks have caused any tsunamis (yet). If that happened right now then they are screwed.
I haven't seen any evidence of the last two occurring.
http://www.democracynow.org/2011/3/14/japan_facing_biggest_c...
In their defense here though, I believe they got that pumped out pretty quickly.
The process of nuclear decay is well understood, so you can compute, given any mass of nuclear material, how much heat and for how long that mass will generate sitting in a pile by itself. You do that calculation in the presence of full moderation (all control rods inserted, below the critcial level) and without moderation (control rods out).
Now you design a thermal sink which can absorb that much heat indefinitely when either covered in soil or sitting out in free air (choose the option that has the worst heat conduction) Note that modern reactors like the Pebble Bed can't really do the whole core meltdown thing, but those that can you can design what is essentially a bucket of boron laced sand underneath them such that in the event hell breaks loose with the control rods out, the core will melt and diffuse into the sand which will drop it below critical and now you're solving for "non-critical pile turned off, how much heat from time 0 to n?"
Ok, now lets see what can cause this reactor design to cause any damage. Hmm, well its immune to anything that doesn't hit it directly and destroy the containment vessel.
So basically anything except a direct hit by an asteroid or perhaps a nuclear weapon.
Now if you look at Pebble Bed reactors they take the approach that the fuel itself is in self contained containment vessels, you can dump them out across the floor and they will cool off without doing anything else and without any radiation.
But to re-iterate what others have said, there is a security/hazard/value trade off, airplanes fall out of the sky all the time and yet people still fly, automobiles kill their occupants and yet people still drive, coal miners die trying to dig up coal and yet they keep mining.
Nuclear reactors are no different in this regard, they have a 'worst case' scenario (similar to a plane losing a wing at altitude but we're not all demanding that planes have a parachute under the seat cushion), if we only have to deal with worst case reactor scenarios during 9.0 earthquakes, I'm ok with that. I can understand if you aren't.
I don't know what you consider 'Serious Harm to Humans', but as of Sunday, there were an assumed 160 people with radiation exposure (9 confirmed).[0]
From what I remember on the news the other day, the reason for the failures of the plants was the fact that they had not conceived of an earthquake and tsunami of this magnitude. PM Kan said that there were adequate protections in place for the facilities, but the earthquake was beyond the conceived scope of the protection.
Also, while 20km from site 1 have been evacuated, they've needed to extend the radiation-affected area to 30km. Unfortunately, it's too wide of an area to evacuate, so they have told people to stay in their homes.
[0]http://jp.reuters.com/article/mostViewedNews/idJPJAPAN-19971...
edited: edited "poisoning" into "exposure" edited: Added evacuation distances
So far, the only report of radiation poisoning which I've heard is a SDF member who was on-site when one of the steam explosions happened.
I believe there were 3 SDF members who were hospitalized for radiation, but I could be wrong (also, I read it on the 共産党 site, so who knows)
According to that, fatal poisoning starts at around 2 Sv. According to the BBC, levels in the surrounding area are 8 mSv per hour, so not enough for acute poisoning given the timings, though not at all good for you. For comparison, a chest x-ray is 60 µSv.
I just wanted to make that clear.
But I don't think it does.
It's not just engineers who are responsible, in any event.
The bottom line is that nuclear power is still safer than many activities/environments that regular people encounter on a daily basis, and is certainly safer and cleaner than other, much more prevalent sources of power generation. It's obviously not the safest or cleanest, but it's up there.
I really can't say how many lives are enhanced or saved by simply being more efficient. And I can't predict the future, so neither do I know if nuclear power will ultimately be our downfall. But the question is far more complex than "society considers the loss of life acceptable." Society makes these choices to support and sustain better (and more numerous) lives.
Calculate, how many lives are already saved and will be saved in future by nuclear reactors in comparison to other sources of energy. Calculate how many lives will be lost in worstests scenarios. Multiple number by probability and sum up.
For example:
* nuclear reactor can save 1000 lives per year in 100 years of it life with 0.9999 probability;
* in worstest case, with 0.0001 probability, it can kill 10000 humans per year in 1000 years.
Result: 1000⋅100⋅0,9999 + −10000⋅1000⋅0,0001 = 98,99E3
0,0001 probability is too optimistic - we already have Chernobyl and few other smaller nuclear disasters while number of nuclear stations is much smaller than 1K.
Energy Source Death Rate (deaths per TWh)
Coal – world average 161 (26% of world energy, 50% of electricity)
Coal – China 278
Coal – USA 15
Oil 36 (36% of world energy)
Natural Gas 4 (21% of world energy)
Biofuel/Biomass 12
Peat 12
Solar (rooftop) 0.44 (less than 0.1% of world energy)
Wind 0.15 (less than 1% of world energy)
Hydro 0.10 (europe death rate, 2.2% of world energy)
Hydro - world including Banqiao) 1.4 (about 2500 TWh/yr and 171,000 Banqiao dead)
Nuclear 0.04 (5.9% of world energy)PS. If something will blow up our Earth, it will be even safer than nuclear energy! (If we calculate number of deaths per TWh).
http://www.scientificamerican.com/article.cfm?id=coal-ash-is...
When it comes to nuclear energy, perception is more important than reality.
When you read nuclear news website (http://www.world-nuclear-news.org/), it seems the issue is potentially very serious, where the potentially become less and less uncertain rapidly. Given that this news website has the support of the world nuclear association, I would be inclined to trust them most than any general news channel out there (being tv/journals or of course Japanese gvt).
What I don't understand is why the walls meant to protect the plant from a Tsunami were too low.
Not at all true for the intellectual engineer types I know. You may want to reassess how much of your certainties are cultural.
it has been inconceivable to me that people making nuke plants could possibly underestimate the risks.
That sounds so inconceivably naive to me that, out of the context of the rest of your post, I'd be sure it was meant sarcastically.
I applaud your more measured approach, but I must say that, as someone who has read most of the stories and comments regarding this topic that have hit the front page, I do feel that you are decidedly in the minority. There are plenty of people rushing to call this a horrendous disaster, who are privy to the same limited information, and who are likewise doing very little to contribute to the discussion.
The information we do have tells us it's bad; the information we don't have doesn't tell us how bad.
1 - work to close existing nuclear plants
2 - work to make sure no new ones are built
That, in turn, would not only forestall global warming, but possibly prevent some of the "hard crash" scenarios that could happen on the way down from the oil peak.
Unfortunately, getting rid of cars would probably be much harder than getting rid of nuclear power plants.
So I'd vote to start on something that's realistically accomplishable in the relatively near term: get rid of existing nuclear power plants, and keep new ones from being built.
The onset of global warming and the oil peak are starting to prove that building economies around suburbs, highways, and long commutes is unsustainable anyway.
See this great documentary, "The End of Suburbia":
Nuclear power has overwhelmingly been shown to be safe, and something can be safe and have unexpected Big Deals at the same time. That's a non-binary attitude that this polarizing subject doesn't exactly favor, as shown by this thread in numerous places.
I mean, that's part of being human, isn't it? Nuclear power is safe. Humans build nuclear power. There will always be a human element...
Of course, you're presenting a vastly incomplete list. We can also do things like:
3 - advocate extra layers of redundancy
4 - analyse what could have been done up-front to eliminate the possibility of this happening given the conditions of the earthquake+tsunami and implement the findings
5 - work to replace older nuclear reactors (with less-safe designs) with new reactors with state-of-the-art safety features
...
1. Work to close the existing nuclear plants, most of which have been sitting around 30+ years.
2. Work to replace that aging technology with newer, safer designs like the pebble bed reactors.
Because we don't have any actionable ones?
But, okay, as you wish. I have the crisis firmly in mind now. I will not "rush to believe that everything is fine" or anything.
So.
Do you have any advice about what action I should take next? I live twelve time zones away, am a citizen of a different country, and have only a passing acquaintance with nuclear engineering.
I can't accomplish anything useful by panicking. I can't change building codes from N years ago, I couldn't prosecute anyone in Japan for negligence even if I had any evidence of same (which I do not), I can't dictate to Japanese industry even if I knew what to do (which I obviously don't), I can't run the Japanese government, I can't even vote in Japan. Neither I nor anything else we know can stop radioactive elements from decaying, and I can't unwind time and stop the earthquake.
I suppose I can raise my blood pressure, and raise the blood pressure of everyone else I know, and we might even achieve mass hysteria. Is that really a good idea? Why? Like every citizen of the USA, I happen to have some experience with mass hysteria. It didn't turn out well in 2001. I'm not anxious to see more of it.
What would you like me to do, instead of waiting for events to unfold, staying away from certain portions of the Japanese coast, hoping that various Japanese nuclear engineers have done their duty well, and meanwhile focusing on other things?
This is the meat of the entire thing, I think, and those upvoting you are feeling the same way, so let's have a Robin Williams/Matt Damon moment, okay?
YOU CAN'T DO ANYTHING. RELAX AND WAIT.
YOU CAN'T DO ANYTHING. RELAX AND WAIT.
YOU CAN'T DO ANYTHING. RELAX AND WAIT.
This isn't your fault, either. It's the media's, for setting an expectation of knowing about something before it's over and for moving on before the long-term ramifications are widely disseminated.
I keep on thinking of Akira Kurosawa's "Dreams..." (One of the segments deals with just this kind of scenario. The protagonist finds himself in hell after a nuclear disaster.) A horror like this has been in the cultural subconscious of Japan for decades. They always knew that there was a possibility of something like this, but they chose to gamble against it happening.
They didn't do it because they were foolish, or naive. They did their best to avert that disaster. The people had faith in the talent and skills of those engineers responsible.
It's our nature to want to see the good... even in a horror like this. (Especially a bunch of people who are willing to risk everything to start a business.)
> Apparently people don't want it to be a big deal, but it's
> slowly turning into a big deal.
I think that the reality probably boils down to:
It's possible to do nuclear in a safe way. It's even possible
for humans to build such a system (i.e. the complexity
is not out-of-reach), but it's possible that (like economics)
this fails to take into account how illogical humans are (e.g.
cutting corners on something that is *really* dangerous).So no, it's not a giant conspiracy, it's just normal human fear of the unknown...
1. In reactor 4 spent fuel rods are burning and radioactivity is being freely vented in to the air. NONE of the optimistic reports suggested this possibility but I see a prophetic article at http://www.nytimes.com/2011/03/15/world/asia/15fuel.html.
2. Reactor 2 has had an explosion that has damaged the core containment structure - something we were assured would not happen.
Why were engineers so optimistic, while the ground reality is so much worse? Probably the complexity of the system escapes us and look at small parts of the issue and assume they are under control. In reality many things are interacting and the combination can overwhelm defences. For eg. as water is being routed to reactors 1, 2 and 3 to prevent meltdowns, the spent fuel rods are overheating.
Hubris strikes again.
There are way too many people on here who've been drinking too much of the radioactive koolaid doled out by the nuclear industry.
The general consensus here tends to be that nuclear power is wonderful and amazingly safe.
Well, we're seeing them being proven wrong yet again. How much more proof are they going to need? How many more nuclear disasters is it going to take?
This could definitely have been far, far worse by now.
It still can. The disaster may be far from over.
And it may take quite a while to calculate the real cost of this disaster, both economically and in terms of human life.
[1]: http://www.iaea.org/newscenter/news/2007/npp_extension.html [2]: http://en.wikipedia.org/wiki/European_Pressurized_Reactor
Yes, I would be thrilled if we switched entirely to solar, wind, geothermal, and hydroelectric power sources, but nuclear power isn't anywhere near as disastrous as the people strongly against it would like us to believe. It's also not as safe as a lot of people would like to think, but, by and large, it is fairly safe.
Most of Brazil depends on a single hydro facility with endless miles of aluminum wires crossing the southeast part of the country. If anything serious fails there, the country pretty much stops.
Renewables like solar, hydro, biomass, and wind have their place, but you don't generate solar during night, you may want to spare your water during a drought, you may need to eat the biomass and you may have days without wind. Nuclear too has its place. Technology is a tool we should wield with reason, not passion.
[1] http://www.research-in-germany.de/61660/2011-03-08-molten-sa...
If some of you anti-nuclear types get frustrated that I and others are not rushing out to forswear nuclear forever and ever amen, it's not because we don't understand the risks. It's because we don't ignore a death just because it happened in a non-radioactive flood or a non-radioactive coal mining accident and didn't involve any OMGRadiation!!1!. Nor are deaths caused by nuclear issues magically worse than being killed in a flood or a coal mining accident. Dead is dead. Someone who wants to be seen caring waves around their fashionable concerns and waits for congratulations from their peers; an engineer who wants to care considers the costs and benefits of the whole system, and doesn't simply assume either is zero without evidence. Regardless of how bad this particular crisis may become, it still nets out that people are dying every year because we're too cowardly to look at nuclear head on and use more of it and less of the even-more dangerous other technologies we are using, so that we can feel good about our irrational fear of OMGRadiation!!1!.
Indeed....please provide us with the list of nuclear disasters, it should be an easy exercise judging by the tone of confidence in your post. Just for fun, throw in some stats on deaths per kwh of electrcity.
PREDICTION: you will not respond to this, because there have been no nuclear disasters. And no one disputes that in practice, nuclear is the safest form of power statistically. If you want to assert that nuclear power is incredibly powerful and dangerous, that is one thing, but trying to pass off potential disaster as reality, is a but disingenuous.
Spain is known to be investing heavily on concentrating solar power.
I'm not sure that's an accurate assessment, given that solar will probably become much cheaper as more solar plants are built.
And, as we're seeing with the Fukushima and Chernobyl disasters, the real price of nuclear could be much higher than just the price of a power plant.
What would be your price tag on the lives lost in or ruined by these nuclear disasters? (not to mention the economic cost stemming from the areas being contaminated by nuclear fallout)
"Not even the USA can afford to go 100% renewable with a price like that."
Of course they could. They could start by giving fewer handouts to the rich in terms of bailouts and tax breaks. Then they could cut the military budget so that the US no longer spends more on its military than the rest of the world combined. And they could legalize drugs, and get rid of the War on Drugs, cut spending on filling prisons with people who commit victimless crimes, etc.
All together that would make for many trillions saved (plus a handy profit on taxing legal drugs). Then the US could easily afford to go 100% solar (and probably much more), without any of the risks of nuclear.
I understand that there are many political reasons why none of these things are going to happen in the US any time soon (though some estimates put legalization of pot on 10 year horizon, when the baby boomers start withdrawing from the political scene, and as the younger generation is far less afraid of pot). But it's not like these things couldn't happen.
It's all a matter of political will.
If there's one good thing that's come out of this latest nuclear disaster is that it's starting to wake people up to the true dangers and costs of nuclear power. Hopefully they won't need many more such lessons before they get the point.
Do you really think the USA will stop building coal and natural gas power plants any time soon?
How many kwh of electricity is your life worth?
How many kwh or electricity are the nearly 1 million people who died as a result of the Chernobyl disaster worth? [1]
And I'd love to hear you show me a list of solar array or wind farm accidents that prove nuclear power is safer than either.
If Chernobyl or the Fukushima plants were solar arrays or wind farms, how much environmental damage and cost in human suffering would there have been were they to have been destroyed?
I'm looking forward to hearing you sing about how nuclear is the "safest form of power statistically" if the radioactive cloud from Fukushima ever winds up floating over your home town.
---
[1] "Nearly one million people around the world died from exposure to radiation released by the 1986 nuclear disaster at the Chernobyl reactor, finds a new book from the New York Academy of Sciences"
Is your home off the grid? Have you really considered the compromises that have to be made to live entirely(electric, heating, cooling, transport) from wind and solar? It's not easy, it demands changes to all aspects of ones lifestyle and has a significant price.
Just how many people do they kill?
You got any stats on that?
"The by-products of mining and industrial production are often dangerous and result in disease"
How does that compare to the hazards of mining radioactive ore and the hazards from storing and transporting nuclear waste?
"Have you really considered the compromises that have to be made to live entirely(electric, heating, cooling, transport) from wind and solar?"
These compromises aren't necessarily all bad. For instance, if the impact to transport means that we'll have to live on goods made locally and not be able to commute as far to work, that could make for stronger, more pleasant, and more sustainable communities and economic systems.
"It's not easy, it demands changes to all aspects of ones lifestyle and has a significant price."
Does that price approach dying of radiation poisoning from a Chernobyl-style disaster? Or how about having your children be born with all sorts of mutations caused by radiation? Or of poisoning the environment with nuclear waste?
Good luck getting the rare earths from China for all those green technologies if you have to get them from local sources. The one big US mine was shutdown. The reason?
"In 1998, chemical processing at the mine was stopped after a series of wastewater leaks. Hundreds of thousands of gallons of water carrying radioactive waste spilled into and around Ivanpah Dry Lake."
Source: http://en.wikipedia.org/wiki/Mountain_Pass_rare_earth_mine
But it's okay because, currently, we get all those rare elements from China, where you don't hear about the pollution and accidents. Of course, China is saying that they don't want to share with everyone else any more, so that may change soon.
And why couldn't solar panels be developed without them?
Why not put a few tens or hundreds of billions (a tiny fraction compared to TARP or how much the US spends on the military) in to research in to these technologies to make them less dependent on rare earths?
But, as for the availability of rare earths outside China:
"As China slashes exports of rare earth elements, U.S. mine digs for more"
"Molycorp Inc., which owns the open mine, plans to dig out about 40,000 tons of dirt a year by 2014, up 1,200% from the current rate of about 3,000 tons.
The Colorado company is boosting production to meet an insatiable global appetite for rare earth elements..
The mine, about 16 miles from the Nevada border, has one of the world's largest deposits of rare earth elements outside Asia..
The company is spending more than $500 million to modernize and rebuild the 2,200-acre facility. The project is expected to create hundreds of permanent jobs and eventually produce rare earths at cheaper rates than mines in China."
http://www.latimes.com/business/la-fi-rare-earth-20110220,0,...
also:
"China's monopoly of the supply of strategic "rare earth" minerals will end when the Australian mining corporation Lynas brings a massive new refining plant in Malaysia into operation later this year...
The company has invested about $230 million in a refinery covering about 20 hectares which in September is due to start processing about 11,000 tonnes of rare earth oxide a year."
http://www.vancouversun.com/China+lose+monopoly+rare+earth+m...
Wind can't do base load power, either. Maybe someone will work that out by, I don't know, storing the energy in a flywheel or something. But they haven't done so yet. It's also dependent on our solar energy budget (as is solar, obviously). Conservation of energy is a pain, but no one knows how to violate it yet.
How do you know how much something like that would cost to develop?
Come on, do you expect to be taken seriously? Make a reasoned argument, I'm willing to listen. If you can quote any sort of a credible science agency that claims Chernobyl actually contributed to major death, I would consider it.
You can't simultaneously accuse your OP of being disingenuous about nuclear power (which he is, and I agree), then claim there have been no nuclear disasters, because that is probably more disingenuous than the original claim. That's just not true.
Are we working with the same definition of the word disaster? Even bloody Wikipedia, which I'd hardly call the tome of truth, calls Chernobyl a disaster[1]. Human life, property damage (ask Belarus), worldwide fallout...you don't get to rewrite what disaster means so that nuclear power keeps an untarnished image. There has been at least one. Debatably -- and I don't care to get into it -- there could now be as many as three.
There's a parallel with airliner crashes. More people die every day on highways, but an airliner going down is a very serious thing because there are hundreds of lives suddenly ended. So it was with Chernobyl: due to a catastrophic failure of engineering, humanity, and government, dozens of peoples' lives suddenly ended. You can argue that tens of thousands of lives are now in jeopardy due to the radiological effects. That is a disaster, regardless of any pro/anti-nuclear agenda.
Hundreds of people die every year, just mining coal. How many people have died from nuclear power generators in their entire history? Disingenuous indeed.
http://www.who.int/mediacentre/factsheets/fs303/en/index.htm...
There are a lot of relevant statistics in that document, such as the thousands of thyroid cancer cases directly attributed to the radiation exposure, not to mention the tens of firefighters that died saving the rest of the world. I would hate to live in your world, where there's a threshold of death to call something a disaster -- you are really minimizing the effects on hundreds of thousands (potentially millions) of people, simply because they haven't died yet or at all. How about getting uprooted from their homes and lives?
Just as I pointed out with my airliner analogy, the deaths from mining coal are over time, and many probably attributable to basic industrial accidents. Black lung has kind of been figured out, hasn't it? Five hundred coal miners didn't wake up on a Tuesday and die from coal poisoning, and as a result we're not talking about a disaster that needs investigation with coal power production.
What about those that die mining uranium? Not talking about them, are you? The Navajo would probably like to tell you about their history with uranium extraction: http://www.epa.gov/region9/superfund/navajo-nation/index.htm...
I agree that nuclear power is statistically safe, but you are really skewing facts and doing a great disservice to less-educated readers about the (real) dangers of nuclear power, and calling it science elsewhere in this thread. This isn't a binary proposition -- something can be really safe and have the occasional Big Deal. Just like air travel.
Regarding proof: I don't think anything has been proven, yet, except that there have been a lot of powerful forces at work with this disaster.
Doesn't compare to the potential consequences of a nuclear incident, but it's quite possible to build and mishandle crappy coal infrastructure, too.
You've had one and a half. TMI had no ill effects on health, Chernobyl was caused by Soviet incompetence, and Fukushima is the result of an earthquake 7 times more powerful than it was designed to survive. Compare that to the damage caused by oil spills alone.
No power source that is economically viable on a large scale is 100% safe, including nuclear. They do their damndest, but sometimes it fails. There were some design flaws in Fukushima, namely the placement of the backup generators and the height of the tsunami barriers, but the precipitating earthquake was still the strongest in 1200 years. It looks like the containment vessel on the #4 reactor has been breached, and that's very, very bad. Still, the only people injured were those injured by the hydrogen explosions, not by radiation. There's been a few people (~12) who suffered radiation exposure, I believe all plant workers.
Is this event bad? Yes. Could it be another Chernobyl? Probably not. Reactor 4 is on fire, and is releasing radiation into the atmosphere, but on nowhere near the scale that Chernobyl did.
Most of the "optimism" yesterday was based on what had actually occurred: the coolant had failed, #1 was flooded, and #3 had encountered the same problems. Both reactors had hydrogen explosions outside of the containment vessel that didn't compromise them. No significant radiation had been released.
Today is a different story. We'll keep an eye on things and see how they progress, but the optimism was based on the situation at #1 and #3, not the yet-to-happen situation at #2 and #4.
People keep mentioning this as if that matters. The fact is that it happened, and there's really no telling when future natural disasters will strike any given nuclear plant. All we know is that they can happen and that if disasters on this scale do happen, nuclear reactors are not up to surviving them.
"Reactor 4 is on fire, and is releasing radiation into the atmosphere, but on nowhere near the scale that Chernobyl did."
Yet.
But this disaster may be far from over.
"There's been a few people (~12) who suffered radiation exposure, I believe all plant workers."
That's not what I'm hearing. From a former nuclear industry executive and whistleblower interviewed recently on Democracy Now:
"they talk about 160 people that have been contaminated. That’s all they’ve tested. Basically, everything they’re testing is coming up contaminated in that inner couple of miles around the plant. You’ve got radiation being detected 60 miles to the north in a Navy helicopter, a hundred miles to the east on a Navy aircraft carrier. So, it’s not clear to me that that cloud is not looping around and affecting Japan."
http://www.democracynow.org/2011/3/14/japan_facing_biggest_c...
As for this not being on the same scale as Chernobyl, I doubt even a full, uncontained meltdown would be as bad as that. Chernobyl made heavy use of graphite, which burned for a long time, spewing long-lived fallout everywhere. Fukushima I uses a different design, with less inherent risk.
Wikipedia has a pretty decent article on the matter: http://en.wikipedia.org/wiki/Fukushima_I_nuclear_accidents#O...
Fukushima is still listed as INES 4, or lower than TMI, although that could change.
Actually the reactors came out of the earthquake quite well! It was that pesky tsunami taking out the backup generators to power the cooling systems that's really causing all these problems. And even then, new generators were brought in to fix the problem caused by the tsunami, but somehow nobody thought to check to make sure the new generators were compatible with the plant's power system before trucking them in. Oops.
The mobile generators deal was a fuckup, plain and simple. I think, had they known what the price of failure was, they would have found a way to make it work. I think they were overconfident in the safety systems they had in place.
Even if AT THIS POINT the chances of such a fire are <1% (which quite frankly seems optimistic) we should be very very concerned...
Software engineers especially, but engineers in general, have a tendency to love complex machines. But engineers of all kinds SHOULD know best: that there are ALWAYS bugs, and where you least expect them.
We ought to put aside the politics here: whether you like nuclear power or you don't: we've all been very much dependent on it, and benefited from it greatly. It's impact on life is different, but not clearly better or worse than other sources.
Let's hope the engineers on the ground in Japan are getting very very creative.
This brings up a question I've been wanting to ask since the ordeal started. How much do we know about the severity of radioactivity being spread to Hawaii, California or countries outside of Japan?
Assuming worst case scenarios, are the citizens of Hawaii in real danger of poisoning? Should neighboring countries be stocking up on potassium iodine?
McIntyre, P (May-June 2006). Chernobyl 20 years on. Cancer World, 40-44.
Anti-nuclear groups have hyped up Chernobyl to such an extent that many people have an irrational fear of nuclear energy.
http://www.who.int/ionizing_radiation/chernobyl/en/
http://www.who.int/ionizing_radiation/chernobyl/chernobyl_di...
http://whqlibdoc.who.int/publications/2006/9241594179_eng.pd...
http://www.unscear.org/docs/reports/annexj.pdf
http://www-pub.iaea.org/MTCD/publications/PDF/Pub1239_web.pd...
http://www.iaea.org/newscenter/statements/2005/ebsp2005n008....
We have endless reports from international agencies. Cover-up? I doubt it. Ukraine and Belarus want aid and help, have no interest in covering up, and it’s difficult to believe in an international nuclear industry driven cover-up taking in all those UN agencies.
What did these agencies say? Read for yourself,
http://www.who.int/ionizing_radiation/chernobyl/en/
http://www.who.int/ionizing_radiation/chernobyl/IAEA_Pub1239...
http://www.who.int/ionizing_radiation/chernobyl/chernobyl_di...
http://whqlibdoc.who.int/publications/2006/9241594179_eng.pd...
http://www.unscear.org/docs/reports/annexj.pdf
http://www-pub.iaea.org/MTCD/publications/PDF/Pub1239_web.pd...
http://www.iaea.org/newscenter/statements/2005/ebsp2005n008....
and so on, the list really is endless, you can click through for hours.
What is this "large body of evidence" you speak of? It would be nice to have some reports by reputable scientists but all you've done is spew conspiracy hystaria.
Good scientists--those of the WHO included--do their best with what data they have, and don't make claims that can't be backed up by data. Because there isn't enough data to support it, there will never be a comprehensive scientific analysis of the real impact of the Chernobyl event... at least until we get some kind of time machine tech.
Until then, you can't KNOW the impact of Chernobyl. Sorry, but you just have to GUESS. I realize that makes a lot of people uncomfortable, but that's how life works a lot of the time.
So my point wasn't "I know the real Chernobyl outcome in its entirety! It was baaaaad, man!" It was, "nobody knows the real Chernobyl outcome; we only know some partial results that we've been able to piece together, mostly many years after the fact from inconsistent data." (And that my personal hunch is that there was probably a lot of negative impact to humans which could not be captured in reports such as the ones you cite.)
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2011/03/14/...
One thing I learned in school is that you respect any machine bigger than you.
I have no idea why things went so completely wrong there. I always assumed people who design and build nuclear reactors do so in ways they can't fail. Now I am more inclined to believe they are happy to have plans B through G instead of having a really bulletproof plan A. It's certainly more impressive to list a long series of failsafe devices than just having a very unimpressive core that can cool itself in the event of an emergency.
It appears they were much less respectful than they should have been. Some people may end up paying with their lives.
But clearly no one knows how bad this situation is going to get.
2. The hydrogen explosion on 2 may have damaged containment.
Am I wrong? If you could somehow magically snap your fingers and make nuclear power 100% safe, would you do it?
http://www.bloomberg.com/news/2011-03-14/japan-appeals-for-i...
That fourth reactor had been turned off and was under refurbishment for months before the earthquake and tsunami hit the plant on Friday. But the plant contains spent fuel rods that were removed from the reactor, and experts guessed that the pool containing those rods had run dry, allowing the rods to overheat and catch fire.
Of course, this is assuming that things aren't worse than the official statements let on. The sordid history of the Japanese nuclear industry, including falsification of safety records at Fukushima, doesn't inspire confidence. Japanese nuclear officials are notoriously slippery in front of the press, and the lack of reliable information from Fukushima has been very frustrating. No one really knows what's going on there, and every time the officials claim to have it under control another building explodes.
In Ukraine, Chernobyl related benefits and programs are still funded by 5-7 percentage of government spending each year. In Belarus, government spending on Chernobyl reached 22.3 percent of the national budget in 1991, declining gradually to 6.1 percent in 2002. Total spending by Belarus on Chernobyl from 1991 through 2003 was more than US $13 billion. (Chernobyl Forum, 2006)
In Japan live over 100 million people, in an area the size of California.
If the Fukushima disaster grows anywhere near the scale of Chernobyl, the damage (both economically and in terms of human life) will likely be much, much greater.
Consider that the population density of Japan is less than a third that of a somewhat average-density city like Austin, TX, and is even less dense than that of the state of New Jersey.
There is no evidence to suggest that Dai-ichi is actually a "disaster," let alone one anywhere near the scale of Chernobyl. Do you even know anything about the design of the plant at Chernobyl? Orders of magnitude less safe than even these pretty-old Dai-ichi reactors.
Consider that the population density of Japan is less than a third that of a somewhat average-density city like Austin, TX, and is even less dense than that of the state of New Jersey."
If Austin or New Jersey had either the area or population close to that of Japan, maybe these would be relevant comparisons.
If you want to compare cities, try comparing New York to Tokyo, which at least are somewhat comparable. Though even there, Tokyo is far more populous, while NYC is far more densely populated.
"There is no evidence to suggest that Dai-ichi is actually a "disaster""
I guess you've been reading different news than than I have. What I've been reading says three of the reactors have exploded and a fourth has caught fire. There have already been reports of radiation leaks and at least 160 people have been exposed to radiation (so far). Sounds like a "disaster" to me.
Now, whether it escalates to the scale of Chernobyl (or larger) remains to be seen.
Ok, let's reframe: I shouldn't even have bothered. Comparing the population density of a country like Japan to a state like California (as you originally did) is meaningless.
I guess you've been reading different news than than I have. What I've been reading says three of the reactors have exploded and a fourth has caught fire.
Then you've read wrong, or at least drawn the wrong conclusions from it. I haven't read up on the 3rd explosion, but two of them were "cosmetic" in nature and only affected the building structure around the reactors (the purpose of the structure is to keep weather out and is not designed to keep nuclear material in). Neither of the reactors "exploded." Yes, there were explosions at the reactors, but those are two very different things.
I still don't agree that this is a disaster by many reckonings of the term, but I recognize that people are free to define the severity to invoke it as they wish. I just happen to disagree.
Now, whether it escalates to the scale of Chernobyl (or larger) remains to be seen.
Highly unlikely, but yep, remains to be seen.
All energy sources have risks and I believe that nuclear can be safe and reliable and better than any of the alternatives. In the end we will build nuclear power plants because there is no other large scale source of energy that can power an industrial civilization. (If you think so-called green energy and solar power can save us you need to learn some math. You are an environmentalist dupe). Need I remind all the ambitious hackers on HN that computers and the internet do not run on pixie dust -- it is running on oil, gas, coal and, yes, nuclear power right now. We know that at some point the oil will run out or become too expensive to mine. At that point its nuclear or turn off the lights and the drastic drop in living standards that implies.
This accident will teach us a lot about how to design and build reactors and nuclear power stations and maybe will delay the construction of those new plants which would be the real tragedy of this accident. We need to start building them now.
It's instructive that we've already engineered ways of preventing the problems TEPCO is experiencing at their Fukushima. Many newer reactor designs have a passive residual heat removal system that removes decay heat even without electrical power to run cooling pumps.
http://www.ap1000.westinghousenuclear.com/ap1000_psrs_pccs.h...
You need to learn some reality. You are a nuclear lobby dupe.
As regarding sustainable energy, here's my favorite book on the subject: http://withouthotair.com . It takes the approach I like: "let's just sit down and calculate".
From the Japanese Prime Minister and Chief Cabinet Secretary. My source is NHK World (Japan News):
People up to 30km from Dai-ichi (number-1) plant are being asked to remain indoors. ALL people within 20km of PLANT 1 are being asked to evacuate.
The Japanese Govt. have asked the Japanese people to act calmly. (My comment: Watch the stock market now.)
Here we go (information for PLANT 1 - Dai-ichi):
Number 4 reactor: is on fire. There has been a hydrogen explosion there. There was an implosion of the building structure. Radiation is being released into the environment. Note reactor 4 was not in operation, but the fire has caused spent fuel to heat up generating hydrogen.
Number 2 reactor: there was a blast 30 minutes after number 4's explosion. A hole/crack (trans?) has been observed in the reactor. Radioactive material has been released to the environment.
At 10:22am between reactor 2 and 3, 30milliSievert and at reactor 4, 100 milliSievert. At reactor 3 the reading was 400 MILLI Sieverts. Note MILLI, not micro.
They believe the fire at reactor number 4 is likely the main cause of the dramatic increase in radiation.
The roof of a containment facility for spent fuel has also been damaged. It is possible that a leak exists there too.
> A hole has been observed in the reactor. Radioactive
> material has been released to the environment.
The english translation is very poor. Yesterday they used the phrase: "there is a small chance of a massive release of radioactive material". The correct translation was in fact, "there is little chance that there has been any substantial release of radioactive material"
Previous measurements were in micro sieverts.
Source: https://twitter.com/#!/timeouttokyo/status/47480888463859712
What is the bottom graph representing?
EDIT: Looks like data from a little over a year ago- The date range in the screenshot is from Dec 4th to 5th 2010.
Other text: "100 CPM is equivalent to exposure of 1 micro-sievert per hour". Or, approximately one tenth your rate of exposure when flying commercial.
I keep hearing about seawater being pumped into the reactor chamber but apparently the chamber is still very hot. Where is all this seawater going? Steam? How big is this chamber?
EDIT: Also I've heard of at least two explosions. Does this mean that containment vessels are compromised? What exactly exploded?
Some steam is lost when they vent hydrogen, presumably.
The chamber is pretty large, several meters deep around the core.
The explosions are as a result of the release of the hydrogen/oxygen mix - which does not take much to catch - but they occurred outside the pressure vessel. Such a situations is technically planned for, the building structure "fails outward" allowing the blast out and away from the pressure containment. It is relatively unlikely to damage the integrity of the vessel in such a situation; they are very very strong pieces of kit (at three mile island the explosion took place inside the vessel and I believe it did not compromise its integrity).
At this stage is somewhat unclear but it appears that the third explosion has damaged one of the pressure vessels. However the technical explanations I am seeing are stating that it hasn't compromised the integrity of the containment; instead it appears to be saying that parts of the mechanism inside the containment are damaged (in this case the "torus" which is used as an emergency pressure relief system).
This is actually, though, a significant problem, if true, because it could affect what happens if it finally does meltdown (as I mention in another comment, my working knowledge of this form of reactor is incomplete, but IIRC the torus also forms part of the final emergency response to a meltdown).
Bottom line is; at this stage we know there have been 3 hydrogen explosions at 3 of the units, and one fire at another of the reactors. But it is still unclear the level of damage and risk with each unit - TEPCO (and indeed Japanese companies in general) tend to play down or not discuss details and risk publicly. Take this fire; no one really picked it up until it was out - at which point TEPCO appear to have started mentioning it.
If I had to lay a claim I suspect that reactor 2 at this stage will probably meltdown; loss of the torus is significant enough that it raises the risk of what they are currently doing (i.e. trying to cool the core).
"As of 0:30 pm, the measured value of radiation dose near MP6 was 4μSv/h. The increase of the radiation dose cannot be confirmed at this time."
http://www.tepco.co.jp/en/press/corp-com/release/11031405-e....
I've seen lots of things reported, but I'm always leery of things that have gone through two or three languages to get to us. We've all played that translation party where things get translated into gibberish. I'm going to have to take it with a grain of salt when people get their news from the French embassy (which, last I knew, was not known for nuclear expertise, but feel free to prove me wrong).
...if the fuel pools are not cooled, they will melt down, in which case we’re going to have Chernobyl on steroids."
http://www.democracynow.org/2011/3/14/japan_facing_biggest_c...
Rough translation of the prime ministers speech on reddit: http://www.reddit.com/r/worldnews/comments/g3zel/breaking_ex...
Nikkei Flash Crash - Futures Plummet 16%
http://www.zerohedge.com/article/nikkei-flash-crash-futures-...