Fukushima: What Happened and What Needs To Be Done 370
IndigoDarkwolf writes "The sometimes confused media coverage around the Fukushima Daiichi nuclear plant left me wanting for a good summary. Apparently the BBC felt the same way, and now delivers an overview starting from the earthquake and concluding with the current state of the troubled reactors."
That's the news for ya! (Score:2)
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Not that the BBC's reporting is any good these days. I stopped reading it after they echoed the Israeli military's line on the boat raid last year. Hell, they were pretty much printing word for word the press release given by Knesset.
I wouldn't trust this article either, it reads like a press release from Tokyo Electric Co. TEC have proven to be untrustworthy as they refuse to have best practice at the centre of their company doctrine - it's now known that they did everything on the cheap and thus why the r
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Not that the BBC's reporting is any good these days. I stopped reading it after they echoed the Israeli military's line on the boat raid last year. Hell, they were pretty much printing word for word the press release given by Knesset.
Doesn't sound like the reporting you'd get from Jeremy Bowen [guardian.co.uk]
This was a team name at Geeks Who Drink trivia.... (Score:3, Funny)
Persective (Score:5, Insightful)
Pity that the nuclear problems seemed to overshadow all the vastly more important and tragic aspects of the quake and tsunami.
Re:Persective (Score:5, Insightful)
What quake and what tsunami?
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Persective indeed (Score:5, Interesting)
The waste is the biggest problem?
1. No civilian spent fuel was ever accidentally or on purpose released into the environment, even though transportation of it is common. Soviet military waste was sometimes dumped directly into rivers, but this is really unrelated to nuclear power.
2. The only person that ever died from civilian spent fuel was a guy that got ran over by a train during an anti-nuclear protest. http://en.wikipedia.org/wiki/Death_of_S%C3%A9bastien_Briat [wikipedia.org]
3. If someone used only nuclear electricity (average U.S. electricity consumption) from present reactor technology for their entire life, he would generate about a soda can of waste.
4. Vitrified nuclear waste is completely insoluble in water. It's rather hard to spread it over a large area. Even if it was just dumped into the ocean, there would be no harm to humans - the waste would bury itself in the seabed. We are not using this solution because Greenpeace and other assorted clowns do not understand anything about marine biology or oceanography. http://www.theatlantic.com/past/docs/issues/96oct/seabed/seabed.htm [theatlantic.com]
5. Even if the waste does somehow escape into the environment, it is very easy to detect this. Radiation detectors are very cheap and compact compared to the laboratory setups needed to analyze chemical pollution - so cheap and compact that every radiation worker has their own detector that keeps track of their exposure. This fact facilitates cleanup operations.
I can understand the uneasy feelings, but let's have some perspective. This isn't even as bad as the hazardous chemical waste we already have to deal with (e.g. from semiconductor production, mining and metallurgy), which unlike nuclear waste will remain toxic forever.
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re-breed the waste and use it again. Funny thing about half lifes, the shorter they are the more deadly but the faster they decay...
There is no good reason (in a first world NATO/EU/etc country) to not re-breed the waste and make good use of it several times. Then once no longer hot enough for power generation, use it (in a double loop) to heat water, or provide heat to other industrial processes. It would make a nice stable heat source.
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>>Pity that the nuclear problems seemed to overshadow all the vastly more important and tragic aspects of the quake and tsunami.
Indeed. Many people's lives were shattered. Corporations involved did what corporations do but I do not consider the handling of this situation any worse than BP's spill. Actually, I believe that the operators of the plant were more forthcoming and there was a lot of confusion going on related to what was screwed, where the problems were, etc.. Not to mention that knowing
Re:Persective (Score:4, Insightful)
Not really.
The Japanese have a saying for situations like the earthquake, Tsunami and the immediate aftermath: "It can't be helped." There's nothing that can be done about the tens of thousands of people who were killed. For the most part everything that can be done for the survivors is being done.
The Fukushima situation is not a misfortune on the scale of the tsunami, but it *is* an ongoing crisis. What sets a crisis apart from a misfortune is that it generates a never-ending stream of new and unexpected questions to be answered. What shall we do about the radioactive water when we don't know where its coming from? What should we do about the effect of radioactivity releases on the food supply? How are we going to put this situation to bed with a team that's been working in crisis mode for a month straight?
Of course the immediate run-up to and aftermath of the tsunami was a crisis too, but now we no longer have a parade of new and unexpected problems, but rather a collection lingering and intractable ones. Those demand attention too, but that doesn't mean you can write off the Fukushima situation as something not meriting much attention.
What 'happened'? (Score:3)
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"Obsolete nuclear reactor containment"
There is no such thing. There is only enough, or not enough. Obsolete is not enough. Once it was determined that the reactor design was flawed and the failure-mitigation systems were worthless, the only correct thing to do would have been to refit the design with failure-mitigation systems that were bulletproof.
There are dozens of this sort of reactor still in use. All of them should be fitted with gravity-fed cooling systems, immediately.
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There is only enough, or not enough.
Well, if you want a binary answer, then there was enough nuclear reactor containment.
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There are dozens of this sort of reactor still in use. All of them should be fitted with gravity-fed cooling systems, immediately.
Indeed, although I think the more difficult problem is going to be finding a constant supply of pure water to circulate as coolant when disaster strikes. Most disasters are going to cause hell for whatever container you're using to keep millions of gallons of pure water at the ready.
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Problem #2 is giving a damn about the reactor once it breaks. You need pure water only if you want to restart it. But when you're trying to prevent people dying by busloads, nobody much is going to care if you can restart it. Whatever coolant you have is fine.
What do you mean, "what happened?" (Score:2, Insightful)
There was a massive earthquake followed by an equally massive tsunami that buried the plant under 10 feet of water. That's what happened.
Earthquakes of that magnitude are rare. There have only been 6 in the world since 1900, and none of those were in Japan.
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So we can expect one somewhere every 16-18 years. And we have hundreds of nuclear reactors worldwide. And we still run reactors that are built out of Jenga blocks?
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How many of the hundreds of reactors are along known fault lines?
Of those, how many are susceptible to tsunamis?
Remember...if not for the tsunami knocking out the diesel generators, Fukushima wouldn't have been a catastrophe.
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How many of the hundreds of reactors are along known fault lines?
Of those, how many are susceptible to tsunamis?
Two are in California, near (but not directly on ) fault lines.
One is on a high cliffside, so it's likely not susceptible to tsunami, but the other is close to the sea so is vulnerable.
One plant was built to withstand a 7.0 quake, the other a 7.5 quake, but there's a good chance of a 7.5 or larger quake in California over the next 30 years. Oh and one plant had the entire reactor vessel installed backwards, and at the other plant the earthquake reinforcements were installed backwards.
Neither plant uses the
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Ok... so you are saying we need to fix and/or refit two reactors to ensure they are more robust than they currently are.
I don't think you'll find anyone here who will argue with you on that, except maybe whoever has to foot the bill of course.
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You can pay me now, or you can pay me later.
Statistics are like that.
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You can pay me now, or you can have a disaster later and let the taxpayers go farther into debt to foot the bill.
Bailouts are like that.
Shoot. Corporate presidents like that.
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Ok... so you are saying we need to fix and/or refit two reactors to ensure they are more robust than they currently are.
I don't think you'll find anyone here who will argue with you on that, except maybe whoever has to foot the bill of course.
I'm not saying anything, just answering the parent poster's question.
But since you asked, I doubt that retrofitting any additional safeguards into the current reactors would be cost effective, and you still end up with a 30 year old reactor that's a bit safer.
If it were up to me, I'd say scrap the current reactors and replace them with a more modern design that is more intrinsically safe. Oh, and maybe move farther from the shoreline since if there ever was a big radiation release, the proximity to the ocea
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If it were up to me, I'd say scrap the current reactors and replace them with a more modern design that is more intrinsically safe
I agree wholeheartedly. Newer reactors are better reactors.
Too bad it's been...oh...about 30 years since a new reactor was built in the US.
Although the ocean does provide a convenient and unlimited source of cooling water
Another convenient fact about the ocean: no one lives there. A nuclear disaster will hurt fewer people, then.
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But since you asked, I doubt that retrofitting any additional safeguards into the current reactors would be cost effective, and you still end up with a 30 year old reactor that's a bit safer.
If it were up to me, I'd say scrap the current reactors and replace them with a more modern design that is more intrinsically safe
For sure. I'd said refit, but I'd be even happier with replace too.
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Those are hindsight questions, not foresight questions. In other words, the question is NOT how many reactors are subject to the previously-understated risks that ended up causing the Fukushima disaster; the question is how many reactors have understated risks, of any kind.
Of course, that's much harder to answer. Which is exactly the problem.
decent news source on fukushima plants (Score:4, Informative)
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Nuclear Energy Institute? Isn't that sort of like tobacco health studies from Phillip Morris?
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This is a complex subject, so I'd rather listen to someone who might want to cover his ass but actually knows what he's talking about than to a neutral person with a poor grasp of the issue.
Yes, you should exercise caution when reading industry sources, but they're far better than the anti-nuclear people. The industry of course has an agenda, but at least it knows what it's talking about.
Japan to raise severity level of Fukushima acciden (Score:5, Interesting)
The Japan Times [japantimes.co.jp] reports:
The Nuclear Safety Commission of Japan released a preliminary calculation Monday saying that the crippled Fukushima Daiichi nuclear plant had been releasing up to 10,000 terabecquerels of radioactive materials per hour at some point after a massive quake and tsunami hit northeastern Japan on March 11.
The disclosure prompted the government to consider raising the accident's severity level to 7, the worst on an international scale, from the current 5, government sources said. The level 7 on the International Nuclear Event Scale has only been applied to the 1986 Chernobyl catastrophe.
If the levels they are reporting are correct then every hour (for a few hours) Fukushima was releasing roughly 0.1% of the total release from Chernobyl. If those levels were maintained for a day (which they were not), that would be almost 2% of Chernobyl per day.
Re:Japan to raise severity level of Fukushima acci (Score:5, Informative)
This comparison is misleading, even if the raw amounts of radiation are comparable. The radioactive materials released from Fukushima Daiichi when those readings were taken have a half-life of minutes and don't pose a health hazard outside of the really close vicinity. The materials released from Chernobyl were much more dangerous, as they have a half-life of a couple hundred years, and only negligible amounts of those have been released from Fukushima.
Bottom line: this accident is not at all like Chernobyl, even though the "OMG RADIATION SPEWING FROM REACTORS!!!!!!" media likes to think so.
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The releases from the Fukushima reactors were nearly all highly-mobile radioactive elements such as iodine, a vapour at normal temperature and cesium, a low-melting-point metal dispersed during the venting of steam and hydrogen from the reactor vessels. The Tchernobyl releases included large amounts of everything in the burning core after the entire reactor vessel slagged down and exposed it to the world including strontium-90, a bone-seeker which usually has too high a melting point to be easily released f
Re:Japan to raise severity level of Fukushima acci (Score:4, Informative)
According to the Nuclear Energy Agency [oecd-nea.org] the majority of the radioactivity released at Chernobyl was in Xenon-33 with a half-life of 5 days. This was followed by Iodine-131 (half-life 8 days) and Tellurium-132 (half-life 78 hours). The next most active element released (measured in Becquerels) was only 3% of the Xenon released, and it has a half-life of 13 days.
If I read the report from the NEA correctly then ISTM I was comparing apples to apples.
Furthermore, unless one or more of the reactor cores at Fukushima has gone critical again after the shutdown then any direct product of the fission reactions that has a half-life measured in minutes was gone after the first day of the accident, well before the meltdowns and hydrogen explosions and measured releases of significant amounts of radioactivity.
There are certainly very short-lived isotopes that are part of the decay chain of long-lived isotopes. Iodine-131 is a perfect example. The problem is that they will continue to be created for the duration of the longer-lived isotopes.
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Considering that Chernobyl released several percent of its core directly into the air through a graphite fire, and the reactor that exploded at Chernobyl was rated at 1000 MW (roughly the combined power of units 1 and 2 at Fukushima I), this can only be an extremely pessimistic upper bound.
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I hope you're right. Let's run some numbers. Say 2% of the Chernobyl core got released and let's say only one reactor at Fukushima is leaking and it has half the total radioactivity of Chernobyl. That would mean the Chernobyl release was 4% of the leaking core at Fukushima. The figures from the article indicate 0.1% (more accurately, 0.07%) of the Chernobyl release escaped from Fukushima per hour for two hours.
This would be 4% x 0.0014 = .0056% of the core of one Fukushima reactor.
Given that a si
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Oh, so we're not modding people that compare Fukushima to Chernobyl into the ground any longer? 35 scorn filled replies questioning DrJimbos's intelligence will not be written? DrJimbo is obviously a fear monger, right?
Given the shear volume of damaged fuel involved in Fukushima it is undeniable that vast amounts of contamination has and will occur. Three venting cores and a burning spent fuel pool filled to the brim with waste. At this point the question is; how will the Fukushima exclusion zone compare
Important Events Missing from BBC Timeline (Score:3, Insightful)
Day 1 - pro-nuclear activists claim there's nothing wrong, there's no danger, containment is fine, no radiation will leak
Day 2 - pro-nuclear activists claim there's nothing wrong, there's no danger, containment is fine, radiation leaks are minor
Day 3 - pro-nuclear activists claim there's nothing wrong, there's no danger, containment breach hardly matters
Day 4 - pro-nuclear activists claim there's nothing wrong, there's minimal danger
...
Day N - pro-nuclear activists claim nobody could have predicted a Tsunami on the Japanese coastline
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Dismissals (Score:3)
"I've never seen a pro-nuclear activist claim any of these things."
Aside from the obvious Slashdot postings... the article here:
http://mitnse.com/2011/03/13/modified-version-of-original-post/ [mitnse.com]
Originally stated, in unequivocal terms, that "there will *not* be any significant release of radiation" (that's pretty close to an exact quote). It was widely circulated, widely quoted, and even posted on Slashdot (a few days late, of course). It has since been edited to remove such predictions, but you can find originals on the web.
Your statement that you've never seen such cavalie
Extensive damage and scale (Score:2)
I've taken a very good look at each part of the picture, and I'm amazed how much damage was done to the reactor buildings. Each and every building you see on the picture is much larger as it appears to be on previous photo's and video's I saw. Just compare the cars sitting next to the buildings. Then take a good look at each building: every one of them sustained extensive damage. There is a huge pipe that has been broken outside the most damaged building (3 most likely) - some of the pipes seem to have been
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Explosions are funny things. An explosion INSIDE a structure does huge damage to it, but an explosion outside a strong structure, especially one that has high pressure inside, does very little. The important structures here are the ones you can't see, the steel and concrete pressure vessels that contain the nuclear reaction. The hydrogen explosions mostly seem not to have damaged those.
Zombie apocalypse (Score:2)
I think we've learned that nuclear power has risks but is still much safer and efficient than most of the other possibilities.
On a related note do nuclear plants have the capability to shutdown cleanly? Otherwise the upcoming zombie apocalypse means I need to get the fuck away from any nuclear plants since zombies usually don't make good nuclear engineers.
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GE's AP600 [wikipedia.org] and AP1000 [wikipedia.org] designs will automatically trip and if they lose coolant flow and start to over-heat will automatically blow some explosive operated valves and start a shower of water falling on the steel containment building for 72 hrs without human intervention, which will maintain safe core temperatures. After 72 hrs you need to have somebody refill the coolant pool on the roof of the containment to keep things stable and it's a lot easier to pour water into a reactor coolant pool when the reactor
Nice but a little late (Score:5, Insightful)
It's nice that the Beeb has released this fairly calm and unbiased recap, but less sensationalistic coverage from the start would have been a whole lot nicer.
I've been watching the coverage of this story on a bunch of different sites for the past few weeks, and this [mitnse.com] is the best I've found - the MIT nuclear science and engineering site. Well written factual articles about the situation, almost entirely devoid of speculation and fearmongering, along with background articles on stuff like how toxic Plutonium is, how radiation doses are measured, etc.
Unfortunately Ivo Vegter [thedailymaverick.co.za] is entirely correct: Every mainstream journalist out there should hang their heads in shame in regards to how their profession has covered this incident.
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To be fair, TEPCO was saying almost nothing, the IAEA was scolding them and usually when that combination happens it's Big And Scary Stuff for real. The media had absolutely no meaningful facts to give and they had no scientists to ask because they were complaining about a lack of information too,
This is as much a PR disaster as a nuclear one, probably more so. TEPCO should have given clear, honest, concise data at all times, damn any theories about panic (people panic when they're ignorant). They should ha
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Hmm, I'm not that sure about your theory... I was following the news from Japanese sources and I was getting really good up to date coverage of what was happening and what were the next steps. I was also getting expert opinions and very good schematics of the reactor design, pinpointing what the potential problems were and what should be done about them.
The US news were pretty much useless, reporting 24h old stuff as breaking news or plain making up stuff on the fly. A good part of the European news channel
We can't handle the technology! (Score:5, Insightful)
We need to accept that we are not capable of cutting through the BS and making clear decisions where highly toxic, unstable, and corrosive substances are handled in a complex manner for great profit (hundreds of millions of dollars).
Put another way, we need trusted technologists to tell us if things are safe or not. Apparently these can be bought when there is lots of money to be made.
At best, people don't think clearly. At worst, we are being lied to and as a result people die and whole regions are rendered toxic.
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Technically "meltdown" simply means failure of the primary cooling system. And it most certainly failed, after standing up to catastrophic events far beyond their rated capacity.
So the reactors technically went into meltdown ... and were brought out again before anything actually melted. A number of indirectly neutron-activated elements, secondary byproducts of the fission reaction, were released into the air, and are totally harmless by now. In fact, over 99% of the Iodine-131 is Xenon by now.
In reality, i
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Re:They blew up and are melted down (Score:5, Informative)
You are 100% wrong.
"A nuclear meltdown is an informal term for a severe nuclear reactor accident that results in core damage from overheating. The term is not officially defined by the International Atomic Energy Agency[1] or by the U.S. Nuclear Regulatory Commission.[2] However, it has been defined to mean the accidental melting of the core of a nuclear reactor,[3] and is in common usage a reference to the core's either complete or partial collapse. "Core melt accident" and "partial core melt"[4] are the analogous technical terms."
And although nuclear reactors might be safe while they're operating, they still produce a lot of radioactive waste. This is waste that has to be stored for over 10,000 years. No one on this planet has done anything that could possibly qualify them to design a vessel to store radioactive waste for a period of 10,000 years. Our knowledge of everything from how materials degrade to geological events that could happen simply is not accurate out to 10,000 years. Sure, I guess we could try to maintain the storage site for 10,000 years, but consider that no civilization on this planet has lasted even half that long. (China comes close at 4000 years).
Generating large amounts of nuclear waste is simply reckless given the problems it can cause and how qualified we are to deal with it.
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So, if I think something 10,000 miles away is not critically affected, I must also think that something at ground zero is uncontaminated?
Please don't post again. You're stupid.
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Ummm.... Those idiots have the best disaster response in the world. They did not delay and did not screw up. They did the best they could; far better than the US did in Katrina.
But then don't let your paranoia and xenophobia get in the way of the facts.
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Nuclear Fire Brigage (Score:2)
The "Feynmans and McGyvers" bit made me chuckle, but your point is well taken.
Running a nuclear power plant is one thing. Managing damaged reactors is quite another.
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As a resident of N'Awlins, I feel I must point out that the disaster response after Katrina was far better than the media made it seem to be.
Pretty much like Fukushima, in fact. Things are blown out of proportion, much scare-mongering is occurring.
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I was a disaster preparedness officer with the US Air Force for a number of years. I would not allow foreigners on my disaster site either. What with the language barrier and unfamiliar equipment someone would be sure to get killed, and then you really have a PR disaster.
In the vast majority of single point disasters, a small well trained group can do much better than a large poorly coordinated group. Something about a mythical man-month, except that people die when you screw up.
Re:The truth (Score:4, Informative)
The "building" that blew off is just a light screen around the reactor building itself. It's very light weight panels hung on an equally light frame, designed to screen the reactor building from view. Nothing else. A relatively small explosoin would blow the panels off. They did not "prevent" the second explosion; it was a calculated risk necessitated by a release of steam and hydrogen from the overheated core.
If you've been following the IAEA blog it's serious but not out of control.
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it's serious but not out of control.
Seems like no matter whtat they did, it just got worse, so I'm having difficulty seeing the control you seem to think they have over the reactors in crisis at Fukushima. They're raising the severity level to maximum. [yahoo.com] Ah, there it is... they are controlling how severe it is? Then why don't they just make it less severe?
Building vs falsework (Score:3)
"It's not a building, it's a falsework designed to hide the building. Big difference."
Citation needed. Everything I've seen suggests the structures damaged in the explosions were the top parts of the building housing the reactors. These are not the secondary containment (the thick concrete "drywell" surrounding the reactor pressure vessel) but they very much are buildings. In particular, they cover the storage pools holding the spent fuel.
http://www.gereports.com/how-it-works-white-paper-on-mark-i-containment/ [gereports.com]
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The amount of destruction from those explosions was tremendous.
What does that mean? What got damaged? Looks to me like they were right, the damage was to stuff outside the reactor which was mostly superficial.
As an armchair nuclear plant operator, it sure seems like they have done a very poor job trying to reign in control of the situation.
Suppose you were in charge. How would you get power for cooling reactors and for the hydrogen discharge systems on these reactors? I don't see you doing any better, because the problem wasn't them not doing a poor job, but being unable to do what needed to be done for several days after the tsunami.
I see your post as an example of confirmation bias. You were lo
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Looks to me like they were right, the damage was to stuff outside the reactor which was mostly superficial.
From Wikipedia: [wikipedia.org]
"An explosion was heard after 06:14 JST on 15 March in unit 2, possibly damaging the pressure-suppression system, which is at the bottom part of the containment vessel."
"On 30 March, Japan's Nuclear and Industrial Safety Agency (JNISA) reiterated concerns about a possible unit 2 breach at either the suppression pool, or the reactor vessel."
"On 27 March, TEPCO reported measurements of very high radiation levels of over 1000 mSv/h in the basement of the unit 2 turbine building"
And the m
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They screwed up venting the the reactor into the containment building because they were afraid of needles moving on radiation detectors half a mile away. They though they were doing good PR, buying time for very short half-life isotopes to decay, but instead they got an explosion. From a structural point of view it doesn't matter, but from a practical point of view it is harder to work in a building in which there has been a recent explosion than one that hasn't. Oh, and the PR backfired, explosions suck mo
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Everything depended on the assumption that the coolant had a backup system.
Once that assumption was mooted by the tsunami, the flaws in the rest of the system became known.
One of which is that once you lose cooling and can't get it restarted, you will inexorably have to vent hydrogen into a closed space full of air. Another is that there is no way to vent it to the outside to reduce the effects of an explosion. Another is that an explosion will further damage the plumbing, making it even harder to get the
Re:The truth (Score:4, Interesting)
Everything depended on the assumption that the coolant had a backup system.Once that assumption was mooted by the tsunami, the flaws in the rest of the system became known.
Not really. The real assumption that failed was that even if there was a complete loss of power in the plant, power could be reasonably quickly (8 hours) provided from outside the plant. The problems escalated because no supplies were available due to tsunami devastation, not even freshwater. The power grid was so damaged that an extra cable had to be laid to get any external power.
One of which is that once you lose cooling and can't get it restarted, you will inexorably have to vent hydrogen into a closed space full of air. Another is that there is no way to vent it to the outside to reduce the effects of an explosion.
The hydrogen was vented inside the containment on purpose, to allow activation products to decay. It could be vented outside the containment, but this would increase the radiation emissions, which the operators desperately wanted to minimize at that point. Hydrogen explosion was deemed an acceptable risk. It looks like this kind of mindset, "reduce public radiation exposure at all cost", is what caused the situation to escalate.
Another is that if the cooling system is completely bunged, there's no way to throw external coolant on the thing that has any effect.
The design assumption was that once cooling completely fails, the reactor will be drained, sealed and allowed to melt down. But this would necessitate a very costly cleanup which TEPCO wanted to avoid.
And another is that they stored the "spent" fuel rods in bunches in what is basically an open swimming pool, so that any chance it gets to evaporate the water around it will result in a fire.
Storing them elsewhere would necessarily expose the workers to more radiation. The point of the temporary storage near the reactor is to allow the fuel to lose most of its radioactivity before it is moved to a longer-term storage location.
What's criminal here is that these things were known to be bad assumptions long ago, but these reactors were operating as originally installed.
Each of the design considerations had a lot of thought behind it. The real problem is that the nuclear safety regulations are not based on a realistic risk analysis, but on fantasies (e.g. child drinking maximally contaminated water for an entire year, or somebody eating exclusively spinach for an entire year). As a result, the operators focused minimizing public radiation exposure rather than on stabilizing the facility, which was actually counterproductive.
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The hydrogen was vented inside the containment on purpose, to allow activation products to decay. It could be vented outside the containment, but this would increase the radiation emissions, which the operators desperately wanted to minimize at that point.
I don't think its true that it could be vented outside, because there was no power to run the ventilation system. The ventilation system pumps the air through HEPA filters to remove any radioactive particles, and that can't be done without power. The only way to vent would have been to cut through or remove the containment walls, either of which could have triggered a hydrogen explosion, probably killing the workers attempting it.
If there had been a way to do it, they probably would have done so on Uni
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I think it will take a while for the full extent of this disaster to become known. Tepco and the government have been downplaying everything since day one. When the first plant exploded due to the hydrogen buildup, and they said in effect that "It isn't a big deal - just the superficial structure over the reactors was damaged" I knew for sure that they were painting a totally different picture than reality. The amount of destruction from those explosions was tremendous. What gets me is that after the first reactor building explosion, they still could not prevent the second (and worse) explosion. As an armchair nuclear plant operator, it sure seems like they have done a very poor job trying to reign in control of the situation.
They *intentionally* vented the hydrogen to prevent bigger problems. The explosion was inevitable.
Re:The truth (Score:4, Interesting)
There are a couple of issues I have seen in the reporting and comparing the report to the photos.
First is regarding the build up of Hydrogen. Some hydrogen build up over time is what has been portrayed. The actual is Zirconium is flammable the same as Magnesium and Titanium. All burn in water or steam. If you have ever seen a magnesium engine block hit with a fireman's hose, you get the idea. Powdered Zirconium is considered an explosive. Fine Zirconium wool as used in flashbulbs, but in an oxygen atmosphere. The reaction with water or steam starts at lower temperatures. The reaction is exothermic. The fuel itself adds heat. At temperatures near 800-1,000 C the reaction changes to a fire. This rapid oxidization of the Zirconium is the source of the rapid and LARGE release of Hydrogen. In the presence of burning Zirconium, there is no free Oxygen so in the presence of this ignition source there is no ignition of the Hydrogen in the Hydrogen/steam cloud. After the Zirconium burnt, the air in the room was then able to come in contact with glowing fuel pellets. This resulted in the ignition of the hydrogen.
From a few days ago, there was a report of some fuel rods found up to a mile away and was bulldozed under to shield them. They don't say much about the containment in #3 other than to say it may have been breeched. That is an understatement. Look up and spend a good amount of time watching videos of demolitions of buildings. Note the blast and resulting dust. The flash happens first then the building breaks. Explosions in #1 and #4 are consistent with the shell and a hydrogen explosion inside. The flash is over before the building ruptures. The ejected material is limited in distance and the blast shape is relatively uniform.
Watch the video of #3. There are some striking differences from anything already seen. First as the building ruptures, there is a large flash, much of it is OUTSIDE the building. Ignition may have been triggered by the blast and was due to the blast. Second using Newton's laws, look at the stuff ejected in the blast. This blast is far from uniform from a blast in the top of the building. At the end of the video, note the very large amount of heavy objects falling from the top of the blast dome. Unlike the other blasts, there are large holes from large heavy objects falling on the turbine hall. These are not from the roof of the building. The blasts from #1 and #4 do not have large heavy itmes falling out of it.
Examination of the high resolution UAV photos raises some more concerns. The containment may have been breeched, but most reporters are citing a lack of evidence of this. I'll tell you where to look. Look on the two pipes that run along the turbine buildings. Look between the turbine hall for #4 and the #4 reactor. Remember those pipes are about 10-12 feet in diameter each. Look for onsite vehicles for size references. Note the object sitting on both pipes. It is covered with dust from the #4 unit explosion. Zoom in and take a good look at it. Knowing the width of each of the pipes and the fact it is resting on both of them, guess it's width. Now look at he edge of the item. Care to guess how thick it is? Now note that it has a painted surface. Under the dust layer it is clearly Yellow. Care to guess what it is and where it came from?
While looking at the high resolution photos from the UAW, look next to the reactor 3 building where the pile of plumbing is lying next to the building. All that plumbing is uniform is size. I'm thinking that is scattered fuel rods from the cooling pond. I think the cooling pond is gone and the steam rising form #3 is not from the pond, but form the containment known as the dry well. I can not tell from the photo if the reactor lid is in place. I'm guessing either a hydrogen buildup in the dry-well exploded or the lid to the reactor blew off. This resulted in the outer containment breech shown in the video. This breech then released the contained Hydrogen which then ignited, This is seen as the flash outside the building.
Re:The truth (Score:5, Interesting)
I agree with most of your first three paragraphs, but the second two dealing with the UAV photos I have to rebut.
Note the object sitting on both pipes. ... guess it's width. Now look at he edge of the item. Care to guess how thick it is? ... Under the dust layer it is clearly Yellow. Care to guess what it is and where it came from?
You're implying that it's part of the containment vessel. Let's look at a specific picture for comparison: http://cryptome.org/eyeball/daiichi-npp/pict10.jpg [cryptome.org]
My origin is at the upper left. The object you're describing is at X:20%, Y60%. Note the thickness of the cut off pipe at X:70%, Y:30%. This is thin walled stuff. In other photos you can see the twin pipes are at the same level as that raised section, and similarly supported. The containment vessel is very thick and heavy. If that was the dome or another section of the containment flung from #3, it would have destroyed or at least damaged the pipe. My analysis: It's just a chunk of wall, similar to the chunks laying in front of #4.
... look next to the reactor 3 building where the pile of plumbing is lying next to the building. All that plumbing is uniform is size. I'm thinking that is scattered fuel rods from the cooling pond.
http://cryptome.org/eyeball/daiichi-npp/pict6.jpg [cryptome.org] - Are you referring to the stuff to the lower-left of the steam, and similar-sized stuff strewn across the top of the turbine hall? I think it's too big to be fuel rods, and too small and mangled to be fuel assemblies. It looks like structural steel from the building.
Lastly, if the stuff flung up in the explosion was fuel rods or containment chunks, we'd be seeing much higher radiation levels in the vicinity of the #3 building. Instead the high levels are centered around #2, where there *was* an explosion inside containment that caused a breach.
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When the first plant exploded due to the hydrogen buildup, and they said in effect that "It isn't a big deal - just the superficial structure over the reactors was damaged"
That's actually correct. They downplayed other things but that was totally accurate. You and people like you are spreading unwarranted fear [...] It has ever been thus, those willfully ignorant of science and facts blocking progress
You should have a talk with the professor of mechanical engineering from Caltech, a nuclear reactor safety
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Yeah, well some guy had a talk here last month about something nuclear and he had some pretty bar graphs and even a picture of a monkey. It was quite entertaining because I was on schrooms but I'm pretty sure he (and he was wayyyyy smart but I don't know his name so you can't check it out for yourself) totally thought the problem wasn't a big deal.
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Help yourself. [caltech.edu]
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So is he a mechanical engineer, or a nuclear reactor safety expert? The fact that you are a professor does not imply you know something about nuclear power. What exactly were his arguments? How does he explain the fact that the increases in radiation at the site perimeter were modest?
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In fact a nuclear facility near the sea in a seismic zone was not equipped to properly withstand a tsunami.
It was a big quake but it was 200km away, so dispersion of energy occurred.
You're right it's not much. Standard f*ckup. In other places, buildings that should withstand a quake fall down, killing students (Abruzzo quake).
I recall a video interview with a scientist made before Chernobyl. EVERYTHING that the scientist had said was still true and accurate after that disaster. But in practice somebody thou
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I recall a video interview with a scientist made before Chernobyl. EVERYTHING that the scientist had said was still true and accurate after that disaster. But in practice somebody thought it was ok to run some test disabling the safeguards and Chernobyl happened. In practice somebody else forgot that in case of flooding the backup diesel generators would also fail and Fukushima happened.
It's not so much that they forgot about flooding, but that it wasn't in the design spec -- they designed for a 6 meter Tsunami but experienced a 15 meter Tsunami.
Engineers aren't (often) given free reign to design for any arbitrary level of safety, they are given design parameters that they need to take into account. And everything comes at a cost - a plant that's twice as safe might cost 4 times as much, making its power unaffordable. Depending on who you talk to, that might be a good thing - some people t
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It was equipped to withstand a tsunami. Just a 6m(~18 feet) high one, not the 15m(45-50 foot) one that it got. Sure we could equip it to handle a 20m one, but what if an asteroid lands a bit off the coast, and generates a 200m high wave... what then?
You have a point about Chernobyl, that was 100% human negligence, but Fukushima wasn't much in the way of a human error. Sure in hindsight they could have built a wall that was 10% bigger than needed for the worst event on record prior to that, but that doesn't
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Slashdot will be swamped with nuclear power industry apologists pretending "Not much and nothing" happened. Dissent will be modded to oblivion.
Reality will continue to disagree.
Then, as per Slashdot's usual and customary behavior, nuclear power haters will chime in with some hyperbolic argument in the opposite direction, citing such illustrious sources as YouTube, Wikipedia and the Daily Mail.
Meanwhile, someone will opine that it's George W. Bush's fault (or Dick Cheney, Steve Jobs, Bill Gates or the Easter Bunny). Several hundred posts will go back and forth covering exactly the same arguments and counterarguments as the last 200 times these subjects were brought up.
The minu
Re:Not much and nothing? (Score:4, Informative)
citing such illustrious sources as YouTube, Wikipedia and the Daily Mail.
AFP
Kyodo earlier reported that preliminary figures from the country's Nuclear Safety Commission revealed the battered plant had released 10,000 terabecquerels of radioactive material per hour for several hours.
That calculation prompted Japan to consider upgrading the accident to the highest level -- something that has only been given to the 1986 Chernobyl disaster -- Kyodo said, citing unnamed government sources.
According to the International Nuclear Events Scale, level seven incidents are ones with a "major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures."
BBC News
"Tokyo Electric Power Company (Tepco) may face as much as 2 trillion yen ($23.6bn; £14.5bn) in compensation claims, according to JP Morgan.
The company has been grappling to contain the radiation leak crisis at its Fukushima Daiichi nuclear plant.
On Tuesday, Japan's Nuclear and Industrial Safety Agency raised the severity of the nuclear crisis at the plant to level 7.
Washington Post
Japanese authorities planned Tuesday to raise their rating of the severity of the Fukushima Daiichi nuclear crisis to the highest level on an international scale, equal to that of the 1986 Chernobyl disaster, according to the Kyodo news agency.
Officials reclassified the ongoing emergency from level 5, an “accident with off-site risk,” to level 7, a “major accident.”
Re:Not much and nothing? (Score:5, Informative)
We all use electricity. And we're using more and more of it as time goes on. Coal releases tons of radiation and kills miners as well as being horribly dirty (there is no such thing as clean coal). We're running out of oil and it pollutes. Wind isn't always blowing or in the right place, sun isn't always shining or in the right place, water isn't always available for dams or in the right place and kills huge aquatic populations, not all of the population lives where tidal generators are a possibility... we're running out of options if we want electricity. Nuclear is great for providing a base generating capability, and there's not a whole lot else right now that's feasible or economical, especially considering the amount of nuclear waste we're planning on storing under a rock in Nevada.
Hell, the Fukushima reactor mostly survived the 4th largest earthquake since 1900 [usgs.gov]. And that's a 40 year old design. We're talking the same year that the Intel 4004 was released. That's a hell of a testament to the design of modern nuclear power plants that are more efficient and even safer.
Yes, shit happens. Fukushima failing is horrible. But it's like being afraid of flying when you're perfectly ok with riding your bike, even though you're much more likely to die. [wikipedia.org]
It's not "nuclear apologists". It's realists who want to maintain our standard of life, and understand what acceptable risks are. Life is all about risk management, and flipping out about the word "nuclear" is very poor risk management.
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>Coal releases tons of radiation
1. Radiation isn't measured in tons.
2. Radioactive coal has been mined, but this is not as common as you have apparently been led to believe.
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Radioactive coal has been mined, but this is not as common as you have apparently been led to believe.
Sir, I give you this link [stackexchange.com] for consideration. It was the first link in my google search, which took me 10 seconds.
Re:Not much and nothing? (Score:5, Informative)
Uranium: 828,632 tons (containing 5883 tons of uranium-235)
Thorium: 2,039,709 tons
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That's right, here in Japan they measure it in milli-sieverts but, as an American, I don't have a good grasp of the metric system. Can anyone tell me how to convert to feet?
Milli-sievert (Score:3)
One milli-sievert = 100 millirem. Chest X-ray = 10 millirem=.1 milli-sievert.
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As compared to producing similar power from other methods, especially coal? Yes. Over the lifetime of the average power source (coal-fired plant, nuclear plant, wind turbine, etc), how much pollution of all forms will it generate from inception, through building, through useful life, to cleanup, per unit of power (say, per TJ)? I would guess here that coal would be among the worst for nearly, if not actually, all forms of pollution. Forms that are espoused as "environmentally friendly" do not produce en
Priorites, please!!! (Score:2, Interesting)
Reality will continue to disagree.
Let me FTFY: fearmongers will continue to disagree.
Apart from the usual "OMG, it's nuclear!!!" there are no valid arguments against nuclear power.
Let's have a reality check: it was the worst earthquake that ever hit Japan, the estimated material damage is $300 billion, the death count at this point is 12000 plus 13000 other people unaccounted for, presumably their bodies are either buried under the rubble or were washed to the sea.
All this, and all you hear about in the press is about four power plants???!!
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Okay, so you're saying that even if it happened here, it wouldn't be so horrible.
My point would be that considering our warlike attitude here in the US, it is a matter of time before we lose a war on US soil. Let's assume that the enemy takes us down with a conventional war (normal bombs, not even heavy uranium armored bombs). When that happens, then power lines *will* go down.
When that happens, a bunch of nuclear power plants *will* go up, in the Fukushima "spent fuel pool" manner.
And you don't think tha
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put it into perspective will you. to replace all four permanently damaged reactors at fukishma japan will need to replace roughly 3,000MW of generating capacity.
Wind turbines are roughly 25% efficient in the real world. that means on average a standard 5 MW turbine is really only good for 1.25 MW.
which means to replace the 4 reactors you need roughly 2,500 5 MW wind turbines. or three times the size of the worlds largest wind farm built to date which covers nearly 400km2 of used land area.
to replace just
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I humbly submit the radical notion that instead of a need to produce more electricity, people could learn to use less.
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You can humbly submit it, but unless you're willing to be the first one to shut off the computer and go live in a cave with no comforts of modern civilization, your notion isn't worth much.
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Of course we are using less here (Japan) already. Lights are off in the office most of the day, train schedules have been cut back to about 80% of normal, etc. Summer is going to be pretty intolerable if we can't use air-con. But just look at the disparity the parent points out. There's no way any reasonable amount of behavioral change is going to make up that difference.
Yes, we should use 'green' power sources as much as possible but it's not going to be enough. For the foreseeable future, we will need to
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I wonder how much iodine-131 this is, compared to the amount released into the South Pacific region by French nuclear tests.
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Hydro's good in NZ, but it can't meet demands everywhere - there just aren't enough large rivers running through conveniently damable canyons. Even in NZ, you're apparently falling off the program: "The plan in 1959 to raise the level of Lake Manapouri to increase hydro-electric generation met with resistance, and the Save Manapouri Campaign became a milestone in environmental awareness. Later hydro schemes (such as the Clyde Dam) were also controversial, and in recent decades coal and gas-fired thermal s