Global Voices reports
Large Japanese electricity utility Tokyo Electric Power (Tepco) confirmed on Thursday, March 19 that nearly all fuel in one of four damaged nuclear reactors at Fukushima No. 1 nuclear power plant has melted and fallen into the containment building.
With the design of the Fukushima Daiichi plants, the containment building was a very simple shell protecting the reactor from the elements, but provided no real protection in the event of a nuclear accident. Instead, the nuclear reactor was enclosed in primary and secondary containment vessels, which sat atop a thick concrete pad at the base of the containment building.
In the event of a meltdown, the thick concrete pad is the only barrier between highly radioactive molten fuel and groundwater.
While there has been suspicions that nuclear fuel did melt its way through the containment vessel and to the base of the containment building, until Thursday there was no definitive proof meltdown had occurred.
The implication of the findings is that it will be very difficult to remove the highly radioactive molten fuel from Unit 1. As well, the molten fuel must continue to be cooled with water until it is removed.
Holes and fractures in the concrete base of the reactor building also means that groundwater continues to seep in and become irradiated before draining into the Pacific Ocean, causing an ongoing nuclear disaster.
The official decommissioning plan tells us the plant should be fully shut down sometime after 2022.
(Score: -1, Insightful) by Anonymous Coward on Tuesday April 07 2015, @10:23AM
Flamebait title not referenced/substantiated anywhere in the summary/article.
(Score: -1, Troll) by Anonymous Coward on Tuesday April 07 2015, @10:54AM
Protip: if you don't want crap summaries/articles, ignore anything submitted by _gewg.
(Score: 3, Informative) by soylentsandor on Tuesday April 07 2015, @11:25AM
The bit after the comma (which I suppose you consider to be the offending part) was taken literally from TFA.
(Score: 5, Informative) by wonkey_monkey on Tuesday April 07 2015, @12:41PM
Did you try reading the summary? With your eyes?
Tokyo Electric Power (Tepco) confirmed on Thursday [...] that nearly all fuel [...] has melted and fallen into the containment building.
until Thursday there was no definitive proof meltdown had occurred.
systemd is Roko's Basilisk
(Score: 1) by Sulla on Tuesday April 07 2015, @01:23PM
Tepco, please.
Ceterum censeo Sinae esse delendam
(Score: 4, Insightful) by kaszz on Tuesday April 07 2015, @11:21AM
Nuclear power is great as long as no pointy haired bosses or bean counters are involved in any way..
(Score: 5, Insightful) by VLM on Tuesday April 07 2015, @11:36AM
This is true in all forms of human activity, not just nuclear power
(Score: 1) by Steve Hamlin on Tuesday April 07 2015, @04:36PM
No bean counters at all means the only commerce that exists is real-time bartering of goods and services, wealth must be stored in land and physical objects, and human effort is not allocated very efficiently.
No thank you.
(Score: 2) by kaszz on Wednesday April 08 2015, @01:09AM
No it means administrators of resource management. And that they have limited abilities of control. Ie not save $10 screw which causes a $10 000 000 accident because it makes the budget sheet look good. Or any schemes that gets too much out of touch with the real resources that the economy has to reflect.
(Score: 2) by mojo chan on Wednesday April 08 2015, @10:52AM
True, but the key difference is that most human activity can't cause trillions of yens worth of damage over a wide area, and take decades to clean up.
const int one = 65536; (Silvermoon, Texture.cs)
(Score: 5, Informative) by Jeremiah Cornelius on Tuesday April 07 2015, @05:18PM
Nuclear power is great as long as no pointy haired bosses or bean counters are involved in any way..
Nuclear power is great - as long as you locate it in a fusion source at the center of a planetary orbital system.
There's never been a nuke system that paid its way. Domestic commercial nuclear electrical generation has always been a subsidized, big-corp boondoggle issued as another expensive side-effect of major military suppliers like Westinghouse and GE. Same in France.
Then? There's the poor tolerance for risk, and disposal of waste - inherent in the technology.
You're betting on the pantomime horse...
(Score: -1, Flamebait) by Anonymous Coward on Tuesday April 07 2015, @09:15PM
And the fuck is that different to every other power generating tech?
(Score: 3, Informative) by kbahey on Tuesday April 07 2015, @01:25PM
There are radiation traces of cesium from Fukushima that reached British Columbia in Canada [www.cbc.ca]. Not dangerous, but noteworthy.
2bits.com, Inc: Drupal, WordPress, and LAMP performance tuning [2bits.com].
(Score: 4, Funny) by Jeremiah Cornelius on Tuesday April 07 2015, @05:19PM
Yeah! And now I can find my maguro sashimi... in the DARK!
You're betting on the pantomime horse...
(Score: 2) by moondrake on Tuesday April 07 2015, @06:15PM
While true news like linked in your post is sadly not understood by most people. Isotopes are wonderful stuff for detecting even the smallest effects. It is not good or bad that the cesium is detectable in Canada. I would say its fairly normal and expected.
I do not work with Cesium, but are more familiar with carbon and oxygen isotopes. For example, its normal to correct for the bomb spike [noaa.gov]. I guess you could make fairly scary headlines saying that the bomb testing increased radioactivity in the air we all breathe by a 500 times! And its visible in all trees growing since then (hence, its also in your salad, and many of these C atoms from food will end up being incorporated in your body).
I know you acknowledged its not dangerous, but there is something about radioactivity that gives people the creeps. Actually I worry least about most forms of radioactive pollution because it is so easy to measure. There are much worse things dumped in the sea every day and we have either no way of measuring directly (often because we do not even know what to look for), or that are low or even below detection until they accumulate in our food to toxic levels (mercury).
(Score: 2) by kbahey on Tuesday April 07 2015, @06:28PM
Not only me. The article itself is non-alarmist as well, and says that the levels are perfectly safe.
The reason I posted it is that it is relevant to the event at hand, and also confirms that there is some radiation leak despite the denials prior to the article.
2bits.com, Inc: Drupal, WordPress, and LAMP performance tuning [2bits.com].
(Score: 2) by moondrake on Tuesday April 07 2015, @06:52PM
I admit I may have responded to strongly and agree the article actually does actually a good job of explaining its not so worrisome. The measurement of Cs in water reminded me that after similar measurements of the atmosphere 2 years ago, some sites were claiming that Americans were already dying [newrepublic.com]....
(Score: 0) by Anonymous Coward on Tuesday April 07 2015, @02:00PM
quick and dirty calculation (0.15 cents per kwh):
1 GW x 24 h x 365 days x 0.15 cents = 1'314'000'000 dollars per year
a dirty and dangerous monument that will outlast the great pyramids and paid for by you!
(Score: 2) by KilroySmith on Tuesday April 07 2015, @04:18PM
So what is it that you are calculating?
(Score: 2) by tangomargarine on Tuesday April 07 2015, @06:30PM
The cost of the electricity that the plant isn't producing anymore? Not sure what his point is either, as undoubtedly the cleanup cost orders of magnitude beyond that.
"Is that really true?" "I just spent the last hour telling you to think for yourself! Didn't you hear anything I said?"
(Score: 2, Disagree) by khallow on Tuesday April 07 2015, @02:06PM
Holes and fractures in the concrete base of the reactor building also means that groundwater continues to seep in and become irradiated before draining into the Pacific Ocean, causing an ongoing nuclear disaster.
This is another abuse, here of the term, "disaster".
(Score: 2) by bob_super on Tuesday April 07 2015, @03:59PM
The most interesting part about that whole disaster to me: Given what I know now, which is quite a few orders of magnitude less than what a nuclear engineer knows, I see everything that has happened as logical and predictable from the situation on day 1.
On March 12, the right guy could have drawn a timeline of what was about to happen, with the only uncertainty being when. That would have spared us the massive amount of scaremongering headlines and usual ignoramuses.
I believe that someone must have that for Tepco, and it directed their response. There would have been no shame in sharing.
(Score: 4, Interesting) by Nuke on Tuesday April 07 2015, @04:41PM
As for "needing cooling with water", fuel in a shut-down reactor will emit residual heat for a while (that is what melted it), but the rate of heat output declines rapidly. After 4 years it will be so small as to be absorbed by its immediate surroundings and be conducted away through supports and even insulation. I am a nuclear engineer, and am involved in the off-load refuelling and maintenance of power stations. The residual heat is so little by the end of a four week maintenance period that no special provision is made to disperse it by then - natural convection does it. Let alone four years. Guys like me are even working inside what is normally the cooling circuit - it's just warm enough not to need a woolly jumper under your overalls :-)
The molten fuel will have water over it to stop its radioactive emissions activating the surrounding metalwork any more than necessary. Wonderful stuff for stopping radiation, water is.
(Score: 3, Insightful) by Fluffeh on Tuesday April 07 2015, @09:47PM
This is another abuse, here of the term, "disaster".
I don't know, I've had a breakfasts that can be referred to as disasters... groundwater seeping into the base reactor, getting all "clickey-clickey" on a geiger counter, then getting pumped into the Pacific.... might be worthy of being called a disaster. It's subjective, but I wouldn't refer to this as a "general whoopsie-daisy" in the scale of things.
(Score: 5, Insightful) by drussell on Tuesday April 07 2015, @04:14PM
I don't even know where to begin to explain everything wrong with the linked article. The Fukushima Daiichi reactor problems were (and are) very serious, but WOW, talk about scaremongering, misinformation and BS sprinkled with a few half-truths and incomplete facts. Someone has an agenda, for sure.
For a real play-by-play, including lots of speculation that turned out to be false, see this excellent thread which is over 700 pages long and continues into a second thread (you can start reading a few hundred pages in if you like... :)
https://www.physicsforums.com/threads/japan-earthquake-nuclear-plants.480200/ [physicsforums.com]
As someone who has studied (among others) the SL-1, TMI, Chernobyl and Fukushima Daiichi reactor meltdowns and other nuclear OOPSiesin detail, I'd like to point out a few things.
Firstly, while Tepco has never exactly been completely forthcoming with worst-case scenario predictions and obviously always hoped for the best rather than the worst, they have consistently released virtually all of their information as they get it and updated their projections accordingly. Contrast this with Chernobyl where we (the rest of the world) didn't get virtually any information for many, many years. The US government wasn't exactly forthright with information about the TMI meltdown, either and even today many questions still remain unanswered. Compared to previous nuclear disasters the Japanese have been extremely open and honest about what has transpired and should be given credit for that. The article makes it seem like they've been hiding things when they have in reality been exceptionally open.
This has allowed physicists and nuclear experts to follow along and create their own models, simulations, predictions, etc. The vast majority of the wild speculations of the early days of the disaster have been proven false by Tepco's continuing information releases. Tepco had obviously HOPED in the early days that all of the fuel in the Unit 1 reactor had not melted down completely but most models and even simple knowledge of the Mark 1 containment and the timeline means it was virtually impossible for it to be anything other than completely melted and Tepco has acknowledged this for YEARS now. Trying to make it look like they "finally admitted" it is BS. They just finally managed to do a difinitive test using muon rays (in a rather ingenious manner, I might add) to confirm for sure that there were no fuel rods left in their original positions as had been hoped for (but not expected.)
Interestingly, the Unit 1 reactor, the oldest of the six, with it's Mark 1 design actually should have done better than the other reactors after the loss of power and cooling water because of its design with an Isolation Condenser. This is the only one of the reactors that had a passive cooling system. Had the valves been aligned the correct way when the battery power failed basically all they would have had to do is refill the gravity-fed supply water for the IC from firetrucks. The newer reactors all required active, pressurized cooling water injection.
Unfortunately, though, unit 1 went without any cooling for much longer than initially understood so a complete meltdown was all but inevitable. People may try to blame the operators and while there is plenty of blame to go around, to think that they weren't trying their best with multiple reactors in distress is wrong. Hindsight is 20/20 and there are many things that should have been realized before the accident but they did the best they could with what was at hand and multiple reactors in crisis. Virtually every nuclear power plant in the world could have a similar disaster with the right (wrong?) conditions and lessons should be learned.
Anyway, other problems with the article... They say things like "The implication of the findings is that it will be very difficult to remove the highly radioactive molten fuel from Unit 1.". The fuel was previously molten, yes, but they make it sound like it still is. It is not. It will be a solid mass of corium and has been for some time. They also say "As well, the molten fuel must continue to be cooled with water until it is removed. More misinformation making it sound like it's still a red-hot molten blob. It is still emitting heat, yes, but making it sound like it's way hotter than it actually is right now is scaremongering BS. It's not going to eat through to the centre of the earth or something.
Also, while yes, the reactor buildings do have groundwater leaking into them and I'm sure a bit of radiaton is still making it out to the ocean, the vast majority of the water is being captured, pumped into thousands of giant tanks and being treated with various filtration systems that end up removing everything except the tritium. Making it sound like it is ALL leaking out to the ocean is scaremongering BS. Tepco has been sealing things, pumping out water and even tried to make a freeze-wall all the way around the site to stop groundwater penetration! They recently used some newly-invented-for-this-purpose hydrophobic cement-like mix that to fill a leaking cable/pipe trench that runs nearly 100m! Nifty stuff they've come up with, actually. (see part 2 page 32 of the thread linked above)
They also make it sound like the cause of the diaster was a simple loss of power. The much bigger problem was the destruction of the seawater intake pumps. They could have much more easily supplied power than supplied the water. It was most certainly a multiple-blunder situation. Insufficient seawall protection from the Thunami when they should have known from historic records there could be larger Thunamis than they were designing for... Battery banks, diesel backup generators, seawater intake pumps, etc. located where they would be flooded or damaged if there WAS a larger Thunami than designed for... The list goes on and on...
The article says the molten fuel ate its way though the "primary and secondary containment". This isn't really correct, or at least probably isn't and we certainly have no real evidence of that yet. It ate through the Reactor Pressure Vessel (RPV), yes. That is expected in a meltdown situation and the reactor is designed for that. Since the control rod penetrations are from below the core, up into the RPV, if the fuel melts it is certainly going to eat through this weak point and end up in what is called the Primary Containment Vessel (PCV). The newer containment designs even have the base of the containment area shaped in such a way called a "core catcher" to spread a melted-down reactor coruim blob into a non-critical shape. The containment is designed to contain a melted down core.
What Tepco's muon ray experiment was set up to do was to see if there was still fuel in the RPV where it should have been if there were still undamaged fuel. There wasn't any there. They are now planning a series of tests and experiments to see where it is in the PCV and the area around it... like if any of it flowed into the Torus room, for example. It is likely mostly still within the PCV, the Primary containment. Perhaps a bit is in the secondary containment (concrete areas surrounding the PCV) but the article makes it sound like it is outside the building. That is complete and utter BS!!
The link to the Tepco release on the Muon ray is here:
http://www.tepco.co.jp/en/nu/fukushima-np/handouts/2015/images/handouts_150319_01-e.pdf [tepco.co.jp]
The last few pages detail what they plan to do to investigate where the core is within the PCV using robots, etc.
That's another thing about the article. They make it sound like nobody can go anywhere in any of the reactor buildings due to radiation. That isn't true. They can't go some places (like the basement of Unit 1 near the access doors to places like the Torus room) but there have been all sorts of workers in all sorts of places. They continue to use cleaning, scrubbing, sealing, etc. to make more areas accessible to workers. Making it sound like it's the reactor hall at Chernobyl after the blast is ridiculous.
Gaaaa... What a horrible article... My brain is about to go into meltdown.
(Not that I'm apologizing for the stupidity of the nuclear industry in general, but what a terrible article.)
These are only a few of the things wrong with this article. If you want to know what really happened, what has been done (like the completion of the removal of all of the fuel from the Spent Fuel Pool of unit 4, which on all reactor designs I can think of is located outside the containment and potentially many times more dangerous than what is inside the containment vessels), what is going on now and what is planned for the future, read that thread at the Physics Forums.
(Score: 3, Touché) by Jeremiah Cornelius on Tuesday April 07 2015, @05:23PM
Well.
I feel much better from this explanation. I certainly feel less nervous now, about the possible meltdown of the Hoover dam or the Ivanpah solar farm.
You're betting on the pantomime horse...
(Score: 2) by HiThere on Tuesday April 07 2015, @06:24PM
Different power sources have different modes of collapse. E.g., the Hoover Dam has two possible modes of collapse:
1) The lake behind the dam fills up with silt, and the dam becomes useless.
2) The dam breaks, and floods the downstream area with an immensely destructive flood.
2a) Well, the dam breaks, but it's only a small crack, so the water drains slowly.
2a1) Well, the dam breaks, but it's only a small crack that can be patched, so the water doesn't drain, but the water leaking into the dam gets into the re-bar, rusts it, and the entire dam starts crumbling over a period of decades.
I could have added a bunch more, but I want to call your attention to failure mode 2 (without the subheads). This can easily be more destructive than the Fukishima disaster was...if you don't include the tidal wave. If you include the tidal wave its' about the same. The difference is that it's over more quickly. The main problem with fission piles is that there is no planning for recovery. This would entail reprocessing nuclear wastes, which nobody seems willing to do. And the only way to get rid of them is to burn them in a reactor designed to burn them. Which can probably be done fairly easily, but nobody is willing to build even one to test the design. So even if we don't have nuclear disasters, every time a pile is decommissioned we effectively have a disaster. I believe the name of the design of reactor that burns radioactives to harmless is fast-breeder, but it might be a slightly different design. There are reasons why they are discouraged, but if we won't build them, then fission reactors are a bad idea. (IIRC, they make it too easy to build plutonium, which is much easier to purify out than a uranium isotope, and that's the reason they are discouraged. Not a bad reason.)
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 2) by DeathMonkey on Tuesday April 07 2015, @06:43PM
A dam failure will resemble the mass-murdering tsunami, not the non-murdering nuclear incident.
(Score: 2) by Jeremiah Cornelius on Tuesday April 07 2015, @08:39PM
Dam failure tends not to be an everyday risk, potentiated by operator error, etc.
You're betting on the pantomime horse...
(Score: 2) by zeigerpuppy on Thursday April 09 2015, @01:59AM
This is even worse than a meltdown and should appropriately be called a melt-through.
Elvis has left the containment and is in contact with the environment.
The other thing they'll have to eventually address is how the reactor 3 explosion was so energetic. It's more likely to have been a catastrophic containment failure under pressure or flash steam vaporization than a hydrogen-air explosion.
A prompt criticality (that is brief nuclear explosion) has also been suggested. Fukushima is by far the worst nuclear accident in history (as far as total radioactivity released); just that most of it is via the water vector as opposed to air.
It's tragic that it will happen again if aging nuclear reactors are not shut down. The increased embrittlement of the containment vessel of these old reactors forced the cooling to be slowed on the days of the disaster. The same embrittlement applies to all the Mark I reactors beyond their design life in the US.