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TEPCO Confirms Partial Meltdown of No.2 and No.3 Reactors
blau writes with an article in NHK World. From the article "The operator of the crippled Fukushima Daiichi nuclear plant says findings show that fuel meltdowns may have occurred at the No.2 and No.3 reactors within days of the March 11th earthquake. But it says both reactors are now stable at relatively low temperatures."
TEPCO is also now blaming the tsunami for most of the damage rather than the earthquake.
Relative to what? The sun?
Many of the status reports from early on indicated a partial meltdown. (It was described as "fuel damage" - but that's meltdown).
So how is this news? We already knew the fuel rods had suffered from partial melting/damage. It's almost a given when you see status reports indicating fuel with only partial water coverage.
retrorocket.o not found, launch anyway?
As I recall, the blame was on the tsunami since day one. Sure, there was a brief moment of "The earthquake may have been more responsible than initially thought" a few weeks back, but that didn't seem to amount to much.
Well, I haven't heard of any 3rd parties reporting anything unusual or notable regarding radioactive contamination above or beyond what has been reported already (and TEPCO can't exactly hide stuff that escapes the site.) Surely if it were so horrible then there would be accurate and reasonable reporting on the "true" radiation levels rather than what is reported, but I'm not seeing anything. And anecdotal rumors and information being spread via social networks (especially in a country like Japan that loves rumors) is suspect.
You don't get it. It melted down. That means that no one can live in Japan ever again. Millions will die, This disaster makes the actual Earthquake and Tsunami seem like nothing!
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
Japan has increased by 20 times the permissible level of radiation for schools, to the limits permitted a German nuclear worker. Thousands of parents are protesting, which in Japan is a pretty big deal. The Fukushima plant is out of places to store radioactive water, more storage is weeks away, and they still need to pump water to keep the fuel cool. The evacuation area may expand again. The slaughter and disposal of livestock in the evacuation zone has begun. Nobody really knows whether or not the fuel is burning through all three primary containment vessels on its way to massive contamination release.
Help stamp out iliturcy.
You do realize that the deaths due to radiation from this incident are well... zero. This was no Chernobyl. Yes, the immediate area will likely be unsafe for some time, but by any rational measurement, the worst that happened was the tsunami, which sadly has been pushed to page 5 by "OH MY GOD, RADIATION LEAK, GODZILLA ATTACK IMMINENT!!!!"
The world's burning. Moped Jesus spotted on I50. Details at 11.
The long term effects of this to the population: Nothing. The levels are so low for the population that they're laughably small.
Don't pretend like 0 is the number of people affected by this meltdown. Nobody has been "laughing" since they got kicked out of homes they lost millions of yen for. It's not like someone's going to give that house back to them, nor their cash. School closings smack in the middle of the Japanese school year also mean lots of disrupted youths.
With Japan's prior issues with unemployment, fukushima was the straw breaking the camel's back for many souls now banned from living somewhere safe and known to them. But nobody is talking about the local lives in the cone of influence of the actual meltdown.
Because, you know, all gunshot wounds only hurt locally and we can just ignore the pain if we concentrate on the body parts not hurting. Right?
Maybe, if the earthquake also knocked out the cooling systems.
But it didn't, so it's likely they could have pumped enough water to keep the rods from melting at all, though they would have had a hell of a time sealing the crack.
The fact is that losing electricity to the pumps led to a cascade of catastrophic explosions turned a cracked vessel from a bad thing into a months-long nightmare. And that fact points to naive, negligent, or deliberately penurious design.
Tepco is shifting blame AGAIN.
The Tsunami knocked out the power, but if it knocked out the valve control systems and pumps, why didn't all three reactors melt down at the same time?
How come they started overheating when their back up batteries ran out of power. With the first reactor's batteries failing earlier due to tsunami damage. Mere coincidence? I think not.
http://en.wikipedia.org/wiki/Timeline_of_the_Fukushima_I_nuclear_accidents
The reason the reactors overheated and melted down was because power was not restored to the reactors' emergency cooling systems before their batteries ran down. If Tepco didn't try to handle everything internally for the first few days, they would have gotten power hooked up to the cooling systems much sooner. The Japanese Self Defense forces could have flown in some generators if requested and if they didn't have any I'm sure the US Military would have been glad to help out and airlift a few generators to help avoid a nuclear meltdown.
The key is that Tepco didn't request any aid from outside sources till it was too late and was forced to by the Japanese government.
From what I can see it's a case of ineptitude by Tepco employees that made this situation much worse than it should be been.
Really?? Are you serious???
You should know very well there's a big difference between nuclear medicine and what was released by the Fukushima reactors. If you don't please beg your parents to send you to a different school before it's too late.
Mod parent up.
Some pumps were still running after the earthquake and tsunami, and they continued to run until the backup batteries ran down. Loss of power was the real cause of the disaster. If they'd some backup power source that worked, the reactors would have reached cold shutdown in a day or two, there would have been no hydrogen explosions, and no core melting.
This is really important. A plant could lose backup power for many other reasons: fire, flood, hurricanes, terrorism, contaminated fuel, tank leakage, transformer damage, maintenance outages, or exhaustion of fuel supplies. Hospitals and data centers with backup power have at times lost power for all those reasons.
Read NUREG/CR-6890, "Reevaluation of Station Blackout Risk at Nuclear Power Plants ", from 2005. Volume 2, page 22, has the line "Risk is evaluated only for critical operation, not for shutdown operation. External events, such as seismic, fire, or flood, are also excluded." That, as we know now, is an overoptimistic assumption. The NRC does a statistical analysis on backup power sources, assuming independent failure of separate units, and computes the odds accordingly.
Nuclear plants that need power to reach shutdown need power sources as tough as the containment vessel. That's now very clear.
Which means after the risks hit 1 x "What they can be made to pay", there is no economic incentive to ensure any more safety. Then add in that the company will be paying not any individual losing his savings and you get into a position where the people making these decisions may well be the ones least impacted. If an engineer makes a mistake that causes an event like this he is never going to work in that field again and is going to be working flipping burgers. If a CEO makes a decision that causes an event like this he is never going to work again since he makes millions a year that is not a big deal.
Of course. No seriously impact. Except for thousands of evacuees and a massive economic damage. That is now. The thyroid cancers come later. Dude, the whole you dug yourself into is so deep by now that you might get your personal china syndrome here. Sometimes the point is reached where simply admitting to be wrong instead of digging on might be the best solution.
Ubi solitudinem faciunt, pacem appellant.
The problems are multiple.
1. Is the containment vessel solid? Will this burn through?
2. If the melted fuel gets hot enough to burn you will get radioactive smoke, and such into the air.
3. You are reducing the shielding to nearby people, by removing water that would be in the way.
4. If you made the wrong and not industry standard choice, do you go to jail?
Probably lots of other issues as well.
Even thyroid cancer is realistically not that bad, I say this as someone who is basically just waiting for that diagnoses. I have the precursor nodules. It is slow moving and slow growing, normally speaking. How many cases of cancer are worth not using coal? How many coal miners and asthmatics do you want to trade for each cancer death?
The reality is all of these power solutions have risk, and yes this will have a high economic cost. So does the deaths of those coal miners. Plug it into a spreadsheet and tell us what you get.
Sure we could have safer power than coal or nuclear but it would be so expensive that it would cost economic growth. That would surely kill people unable to get their medicines when their jobs no longer exist in the new reduced economy or keep their homes warm in the winter due to heating costs. Nothing is free, just tell us how you want to pay for it.
In the initial days of the reactor problems, there was concern that some of the core in reactor #1 might not have been fully covered by water, and that some fuel damage may have resulted -- as in a part of it. The claim was that a relatively small fraction was affected before they restored cooling water levels to normal levels, and that the core, while damaged, was largely intact. The "news" over the last week is that the entire core was uncovered for hours (the gauges were not functioning properly under the conditions), the core heated to 2800C or so, and most of it melted and pooled in the bottom of the reactor vessel. And now there is evidence the same thing has happened in reactor #2 and #3. That's meltdown for 3 out of 3 of the reactors operational at the time the tsunami hit.
If you think there isn't a difference between what was initially claimed in the first week of the reactor problems and what is being claimed now, then you haven't been paying attention. Up until the last week the potential for substantial amounts of the core being melted down and flowing into the bottom of the reactor vessel was only speculation by outside experts familiar with the situation. Now TEPCO has data confirming that is likely what has happened. That's the news: that this isn't theoretical anymore. It's likely.
None of this changes the external results of the disaster in terms of radiation release and so on. It's not like knowing it was a full-blown meltdown changes what has already happened. But it does change how difficult it will be to control and clean up (e.g., you can't pump water in and around the hot fuel as easily if it is a blob of solidified lava and metal), and it provokes serious questions about the ability to monitor exactly what's going on inside a reactor during a crisis. If you couldn't reliably tell that the reactor was actually in the process of melting down, then how can you react to the situation appropriately? It's like having faulty instrument readings while you're trying to safely land a plane with no visibility. The TEPCO crew could be the best reactor operators in the world, but if they don't know what is going on in there, they would be thoroughly borked.
We don't have enough data. Radioactive caesium in the soil can require wholesale decontamination because it's readily taken up by plants and makes its way into the food chain. Can. If it's all in the topsoil and you get a cloudburst, you're minus the topsoil and the problem. The newspapers aren't exactly publishing the levels of Americium or Polonium. Nor is there a vast amount of data on just how deep some of the underground contamination was and what the geology is like. If the contaminants are more likely to be flushed out to sea or trapped by naturally-occuring filters, it's a very different situation from if they're going to constantly cycle within living organisms.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
It is true that thyroid cancer is probably the best choice if you get to select which cancer you get. Survivability is very good. I don't want to discourage you, but I have a couple of friends who lost their thyroid, which may or may not be related to us growing up in on of the fallout hotspots of Chernobyl and getting a healthy dose of rain at exactly the wrong time. They all survived, but having to adjust and readjust your thyroid hormone medication all the time can be pretty shitty. Mood swings, depression, life-long dependency on medication. So, even though a vast majority survives it, the impact on your life is not exactly fun. Regardless of our differences on certain matters, you have my best wishes for getting through that if it should strike you. Regarding coal - there are alternatives. I am not saying to abandon all nuclear power overnight - but a controlled phasing out over 2-3 decades leaves ample room for replacement by natural gas, solar thermal, geo thermal, biomass, smart grid demand control and so on, and so on.
Ubi solitudinem faciunt, pacem appellant.
Are you claiming that there is 600 tons of fuel in each of these reactors?
which may or may not be related to us growing up in on of the fallout hotspots of Chernobyl and getting a healthy dose of rain at exactly the wrong time. They all survived, but having to adjust and readjust your thyroid hormone medication all the time can be pretty shitty. Mood swings, depression, life-long dependency on medication.
I already have those issues and quite possibly for the same reason. Forget the mood swings, the adhd like symptoms or sudden weightloss are much worse. The last one is really vicious, because as you lose weight you end up with too much thyroid hormone, which leads to more weightloss, and on and on.
I agree there are alternatives, but the cost is the issue. Money really does mean the difference between life and death for many. I think 2-3 decades is being very ambitious. If we got rid of coal power on that time scale I would be ecstatic, I think we are stuck with nuclear for a hundred years or more. Solar thermal is great where it can be done. Using northern Africa to power Europe would be a great goal. It is not really an option in a place like Japan though. Not enough land to do that, and not enough light either.
Shipping enough coal or natural gas to replace nuclear power plants is expensive too. Again, that cost could well mean lives.
At this point one might question the logic of evaluating the risk at all. As in, "If there's a cheaper method of producing the same amount of renewable base load power that doesn't have any of these risks, we should use that first." Like, frinstance, geothermal. Why play with nuclear fire if you don't have to? Because it's exciting?
Help stamp out iliturcy.
relative to this, I should note that I spent the last week at the NIH. One of their local newsletter articles included the results of an ongoing survey of possible thyroid cancers among the youth in the immediate area of effect of Chernobyl.
Results? A TOTAL (not increase) of 62 thyroid cancer cases in the relevant population.
"I do not agree with what you say, but I will defend to the death your right to say it"
Termal camera measurements, and instrumentation show that the temps inside the reactor pressure vessels are at 270 C max, bad because that means that still is coming radioactive steam from the damaged reactors, good since that means that even if most fuel has melted, it didn't became a bloob of molten fuel damaging even more the reactor pressure vessels, meaning that as bad has is has get up to now, we are not dealing with the fuel out in the open like in the case of the Chernobyl disaster. The submission was pointing to a very short on details press article, but from the horse's mouth:
http://www.tepco.co.jp/en/press/corp-com/release/11052412-e.html
Press Release (May 24,2011)
Submission of a report on the operation of the plant based on the plant data etc. of Fukushima Daiichi Nuclear Power Station at the time of the earthquake to Nuclear and Industrial Safety Agency, Ministry of Economy, Trade and Industry
From the attached documents, we can see an english summary of the damage to the reactor cores in the best and worst case scenario, but if you can read japanese, this attachment:
http://www.tepco.co.jp/cc/press/betu11_j/images/110524a.pdf
has a far more detailed analysis with real data and scans from the operation log and charts from the instrumentation at the operation rooms. The most interesting data aside reactor status and analysis is the table at page 138 that shows seismometer data. The highest readings detected was of accelerations of up to 550 gals at 4th floor of unit 2 and 302 gal at same's unit basement; so we can make an educated guess that the different outcome of the damage at this unit from its twin, unit 3 was influenced by the stronger effect from the earthquake.
Mexico: 100% conservative's America now!
There are two things that are news here (albeit a little bit late). The first is the extent of the melting. There was always a question as to whether the fuel had melted or if only the cladding had melted. Early on a British scientist wrote an opinion that the data indicated that the fuel had melted completely. TEPCO responded saying that it was a possibility, but that the data could also support the situation where only the cladding had melted. When they finally were able to get inside the building of #1, they decided that the fuel had melted completely. Again, there was still a question if this was also true of #2 and #3. Just recently, they have decided that it was true of those two.
The second piece of news is that when they originally went inside #1, they thought that it might be the case that the containment was cracked in the original earthquake. The coolant would have escaped and the meltdown would have occurred within the first 5 hours. But recently, they have discounted that as a possibility, returning to their assumption that it was a loss of cooling ability which resulted in the meltdown.
I'm replying to too many posts in this thread, but again I feel compelled to do it. I watched the TEPCO news reports on TV. I live in Japan and I speak Japanese. It's possible that I misunderstood some things because it is a technical subject and while I am fluent in Japanese, these things are difficult. But your account of the events do not mesh with my recollection at all. This is from memory, but I recall them originally claiming that a large portion of the core had been left exposed for 5 hours. At that point they said that the fuel was damaged and may have melted. However, they felt that the radiation measurements that they were collecting indicated that the core had not melted down completely, only the cladding had melted. Critically, they said that they couldn't tell for sure what the circumstance were without entering the building.
When the British scientist wrote indicating that he felt the core had melted, TEPCO responded very quickly (the same day IIRC). They admitted that it was a possibility that the core had melted. But they felt that the data also supported the case where only the cladding had melted. Without entering the building they couldn't determine which it was.
Like I said, I watched this on TV and I was not surprised in the least that the core had melted down. They said several times that it was a possibility. On the news, when they were planning on entering #1 they headlined it with saying something to the effect, "They will enter the building and hopefully finally be able to tell whether the core has melted or not".
What's frustrating for me is that the foreign press do *not* report what TEPCO are saying. They report only half of it. Hey, I have never had any love for this company. I consider myself a rather extreme environmentalist. I don't have a car. I don't heat my house. I try to live a spartan life. These energy companies are the antithesis of what I believe in. But I really do find myself feeling bad for those guys lately.
For those of you relying only on the foreign press's reporting of what TEPCO are saying, I urge you to consider that you may be the victim of bad reporting/translation more than the victim of deceit.
...and it provokes serious questions about the ability to monitor exactly what's going on inside a reactor during a crisis. If you couldn't reliably tell that the reactor was actually in the process of melting down, then how can you react to the situation appropriately? It's like having faulty instrument readings while you're trying to safely land a plane with no visibility. The TEPCO crew could be the best reactor operators in the world, but if they don't know what is going on in there, they would be thoroughly borked.
The sad part of the story is that TEPCO crew apparently knew enough to figure out what was going on (whiteboard photos prove this), but officially they pretended they didn't know and simply omitted strongly suggestive datapoints from public releases. Only now, when enough isotopes have been blown around northern hemisphere that any interested scientist can sample the isotope ratio in the air and work back the numbers they slowly admit some truth, while still covering up what really exploded in reactor number 3.