Fukushima Daiichi nuclear disaster

[elbows]

What's happening to all the water that they're pumping in? Presumably it is becoming contaminated? Is it being collected in any way? Will it flow into the ground, water table, sea?

They havent said much about it, except when the monitoring for certain radioactive substances int he sea turned stuff up, and they pointed the blame in that sort of direction. Its going to take a while for the detail on this stuff to emerge.

 

[elbows]

Unit 2's spent fuel pool temperatures, which have ben available since Monday, continues to lurk around the 50C level.

Unit 5 & 6 have the following news which I dont yet fully comprehend: 'The pumps for Residual Heat Removal (RHR) was automatically stopped when the power supply was switched from the temporary to the permanent. (17:24 March 23rd)'

Unit 2 spent fuel pool temp down to 40C at 17:00 JST.

Unit 5/6 pump news seems clearer now - the following official status update does indeed indicate that the pump had previous broken (at 17:24 on the 23rd).

Unit 5 RHRS temporary pump has been repaired (24th 16:14), and cooling Resume (24th 16:35)

Now then, the shared spent fuel pool. Its temperature appears to have risen to a level that starts to make my eyebrows raise. But maybe its nothing to worry about as they appear to have started the cooling system shortly before this temp was measured. Here are a range of temperatures taken over time from this pool, computer translated from the Japanese report so please excuse the way its worded.

<Shared pool of spent fuel>
18 - after 6:00, the pool will ensure that nearly full capacity
9:00 - 19 at the time the pool water temperature is about ℃ 57
- Injection into a shared pool (Sun 21 10:37 to 15:30)
16:30 - 21 at the time the pool water temperature is about ℃ 61
13:15 - 23 at the time the pool water temperature is about ℃ 57
- Start the power supply (24th 15:37), and begin cooling (24th 18:05).
18:40 - 24 at the time the pool water temperature is about ℃ 73

Original source http://www.meti.go.jp/press/20110324006/20110324006-1.pdf

 

[ATOMIC SUPLEX]

I'm not sure I fully understand but it looks like a mix of bad and good. Do you think unit 2 is under control for now?

 

[elbows]

I cant really use the term under control about much at the plant right now. There are all sorts of positive signs and progress, but none of them have reached the point where anything like normality can return, where full control is reestablished, and it could drag on like this for many weeks.

I think its pretty hard to guess which problems could yet get worse, or even which reactor has caused the most woe up till now and will be the hardest to sort going forwards, although number 2 reactor is certainly a strong candidate given the concerns that the explosion there damaged the suppression chamber in ways that we have not learnt anything about since. As discussed previously, the high radiation levels at the turbine room at this reactor are already causing some problems with the repair plan, and I've seen nothing that could give us clues about how this will pan out over time.

Its been good to see progress. Its obviously necessary, but it poses two dangers. The first is that as a result of the new actions which are being taken, such as different equipment coming back into use, a new dangerous situation will occur. The second is that we discover some realities about what already happened a while ago, for relatively few of the questions about events during the nightmare week when things started exploding have been answered.

Even if no new bad events happen at the plant, I would be fairly surprised if some revelation about the existing state of at least one of the reactors or fuel pools is not made within the next month. I was certainly hoping to have learnt at least a little bit more by now, its unclear if the authorities know much more than they have said in public, my best guess is that there may be a few worrying indicators or strong suspicions that they have which they are not exactly likely to hype up in press conferences at the moment, but its also pretty likely that there is lots they have not been able to determine at all yet, or that some of the current assumptions are just plain wrong.

 

[Barking_Mad]

Union of Concerned Scientists

Worth reading in full.

...a report coming out of Norway that estimates the quantity of radioactivity that's already been released. In particular, iodine cesium isotopes are now from 20 to 50 percent of the release from the Chernobyl accident. Some of the stories have been reporting this as if it's good news, that this event is not as bad as Chernobyl, but one has to remember that there's still no evidence that the containment structures at the damaged reactors, 1, 2, and 3, have been significantly breached, which is a difference from Chernobyl, where the confinement structure was destroyed in the very early stage of the accident.

So, the fact that radiation releases are approaching the level that they did at Chernobyl is a cause for concern, a sign of the severity of the accident that has already taken place.

The difference with Chernobyl is that spent fuel pools at Fukushima have been implicated, that up to three of them may have damaged fuel and potentially have released some radioisotopes that could contribute to the additional cesium. But, you know, since we do have six reactors, of which four have experienced some level of fuel damage, the potential source term for what could be released ultimately could be significantly greater than Chernobyl.

I would also like to mention there are reports of black smoke being emitted from reactor number 3 today. Authorities don't know what the origin is, but they say they don't think it's a serious problem if this is originating from the spent fuel pool; however, it could be an indication that there has been severe damage to the fuel itself in that there's larger particulate matter that's now being carried into the air in the form of smoke. That would be fuel particles that would include less volatile isotopes, including plutonium.

So, if the levels of a type of radiation known as alpha radiation start increasing, that could be an indication that the fuel itself is starting to degrade and being released, which might be additional cause for concern.

There are also reports of elevated iodine levels as far away as Tokyo that are now violating drinking water standards for infants. A child under the age of one is roughly ten times more sensitive to the same intake of radioiodine, which explains why there is more stringent standards for children and infants. But I think this is, again, an indication that the significant effects of this accident are being felt further away than the nuclear industry has led most people to believe over the last 20 years. Thank you.

....

REPORTER: Hi, and thanks for making yourself available.

I wanted to see if you could react to the EPA/DOE report out late yesterday about the radiation levels, the plume they found northwest of the Fukushima plant, and the 12.5 milli-REMs that they observed over three days, and specifically, whether that changes assumptions that we have domestically about the emergency planning zones or whether that should be reevaluated.

DR. LYMAN: This is Ed Lyman. I actually haven't analyzed those figures yet, but all the numbers I've been seeing do suggest that there was good justification for the U.S. evacuation order within 50 miles and that dose rates are a cause for concern further away than the 10-mile zone that's imposed in the U.S.

So, I don't think we've seen any data to contradict that, our previous assessment that at least a 50-mile evacuation zone is appropriate and that the Japanese should have also imposed such a zone, and that there will need to be reassessment of emergency guidance in the United States based on the evidence that we're seeing now in Fukushima.

REPORTER: Just to be clear, your position is that the U.S. should have a 15-mile evacuation zone in lieu of the 10-mile zone?

DR. LYMAN: No. I didn't say -- I don't think -- no, I don't think we have a recommendation yet what that should be. It depends on the objective of emergency planning.

Now, in the U.S., the basis for the ten-mile zone in the first place was not to prevent increased doses that do not have acute effects but might significantly increase the risk of cancer. They were primarily imposed to avoid the appearance of acute effects, like acute radiation syndrome.

And, again, the basis is the perception that any accident that would cause higher doses further away is so remote that it does not require a high level of those regulatory attention. We think that the bases for those decisions are going to have to be reexamined and made consistent with other government regulations that protect the public from a certain level of harm due to the emission of carcinogens, and where that level should be set I think is not clear at this point.

 

[Barking_Mad]

New York Times updates

http://www.nytimes.com/interactive/2011/03/16/world/asia/reactors-status.html

 

[mincepie]

Some more photos released:

http://www.theglobeandmail.com/news...-japans-damaged-nuclear-plant/article1954640/

http://news.nationalgeographic.co.u...ear-plant-control-room-dark_33629_600x450.jpg

 

[elbows]

Excessive radioactivity found in Tokyo vegetable
Japan's health ministry says radiation above the legal limit has been detected in a vegetable grown in Tokyo. This is the first time that radioactive cesium exceeding the legal limit has been found in a Tokyo vegetable.

The ministry says the radioactive cesium was detected on Thursday in a leafy vegetable taken from a field in Edogawa ward on Wednesday. The vegetable is called Komatsuna, or Japanese mustard spinach. The radioactive level was 890 becquerels per kilogram, exceeding the legal limit of 500.

http://www3.nhk.or.jp/daily/english/25_03.html

 

[Barking_Mad]

from Reuters blog, by a poster:

...whether talking about a group or an individual, "The best predictor of future behavior is past behavior". I agree that the nuclear industry, and TEPCO among other utility companies, having lied, obfuscated, ignored safety requirements, and used political influence to maximize profits in the past -- unless put on a very short leash and monitored by truly independent scientists with the results made public, will do so repeatedly, as long as they can get away with it.

 

[mincepie]

All this massive amount of water put on the plant from the fire/airport trucks must drain straight out into the sea?? They've not said much about this, but it can hardly be good.....

 

[story]

I'm guessing it was a calculated risk, a decision made in the moment: use water to cool the reactors and thus hope to stop a catastrophic explosion / meltdown, against the slow seep and wash of radioactive water back into the environment.

If so, I can't imagine the agony of having to make the decision, live with the knowledge as the consequences of either scenario play out

 

[Barking_Mad]

Rating may be increased to 6. They are saying containment at #3 may have been breached but aren't saying in totality or just one level. However radiation levels appear to suggest it is leaking on a level that *might* suggest a fundamental break.

 

[xes]

What's this I'm hearing about yellow rain? Apparently the oficial story is pollen, but chernobyl also had yellow rain which was highly radioactive.
http://enenews.com/yellow-rain-arou...-by-the-rain-may-have-contained-radioactivity
http://enenews.com/2006-article-yel...oo-government-assured-residents-it-was-pollen

 

[Dr Jon]

What's this I'm hearing about yellow rain? Apparently the oficial story is pollen, but chernobyl also had yellow rain which was highly radioactive.
http://enenews.com/yellow-rain-arou...-by-the-rain-may-have-contained-radioactivity
http://enenews.com/2006-article-yel...oo-government-assured-residents-it-was-pollen

Nah, that's only bee shit.

Surprisingly, samples of the supposed chemical agent supplied to independent scientists turned out to be honeybee feces, suggesting that the "yellow rain" was due to mass defecation of digested pollen grains from large swarms of bees.

Whether the bee shit is contaminated by radionuclides is another matter.

 

[Barking_Mad]

Reuters:

TEPCO says it is possible that the radiation in the water in reactor 3 came from the reactor core.

 

[Barking_Mad]

"Japan's nuclear safety agency says it is highly likely that the Number 3 reactor of the troubled Fukushima Daiichi nuclear power plant has been damaged, leading to the leak of high levels of radiation. <...> The agency said while the reactor appears to have partially retained its function to contain radiation leaks, there's a strong possibility that some part of the reactor is now damaged and the containment function is weakening."

http://www3.nhk.or.jp/daily/english/25_19.html

 

[elbows]

Yep, not good, I guess the water some workers stepped in has lead to this conclusion. The numbers are stupidly high.

The company says 3.9 million becquerels of radioactive substances per cubic centimeter were detected in the water that the workers were standing in. That is 10,000 times higher than levels of the water inside a nuclear reactor in operation.

The level of radioactive cerium-144 was 2.2 million becquerels. Also, 1.2 million becquerels of iodine-131 was measured. These substances are generated during nuclear fission inside a reactor.

http://www3.nhk.or.jp/daily/english/25_10.html

 

[Barking_Mad]

High-level radiation detected Thursday in water at the No. 3 reactor's turbine building at the crisis-hit Fukushima Daiichi nuclear plant appears to have originated from the reactor core, the government's Nuclear and Industrial Safety Agency said Friday.

But no data, such as on the pressure level, have suggested the reactor vessel has been cracked or damaged, agency spokesman Hidehiko Nishiyama emphasized at an afternoon press conference, backing down from his previous remark that there is a good chance that the reactor has been damaged. It remains uncertain how the leakage happened, he added.

http://english.kyodonews.jp/news/2011/03/81048.html

 

[laptop]

suppression chamber

I've never managed to figure out what one of these is for.

In the diagram it seems to be linked to the concrete containment enclosure, but not to the pressure vessel:

So what does it suppress?

This from the US NRC doesn't help me...

There aren't supposed to be pressure variations outside the pressure vessel, are there?

 

[Fuchs66]

I've never managed to figure out what one of these is for.

By no means an expert on reactor design but it seems to be a safety feature incase of a breach in containment. Oh here we go:

Much misinformation about the pressure suppression chamber feature of Boiling Water Reactors in the press... this feature is NOT for normal pressure control at all, but rather is connected to the outside of the drywell, which is OUTSIDE the reactor vessel. Its purpose is to suppress the surge of external pressure in case of a serious breach of the primary.

http://atomicpowerreview.blogspot.com/2011/03/fukushima-daiichi-no-2-suppression-pool.html

 

[elbows]

Once you skip past the first 6 or 7 pages of this document, the diagrams featuring the suppression chamber starts to show this chamber being connected to quite a number of different things. It looks like it can serve multiple purposes, as part of several different cooling systems, and can both supply water and receive steam.

http://www.scribd.com/doc/50630215/Nuclear-Power-Plant-Information-Boiling-Water-Reactor-BWR

 

[elbows]

Actually this document appears to answer the question decently:

http://www.ucsusa.org/assets/docume...40503-ucs-bg-bwr-containment-overpressure.pdf

 

[Barking_Mad]

The situation looks to be worse if anything

 

[Fuchs66]

OK after skimming that document it would appear to have a dual function in case of a breach of containment, suppressing any pressure surges and acting as an emergency water reservoir for low pressure cooling operations. Nice to learn something new.

 

[elbows]

Oh dear, its not just unit 3 that has problems with very radioactive water in its turbine room:

Tokyo Electric Power Co. said Friday it has begun injecting freshwater into the No. 1 and No. 3 reactor cores at the crisis-hit Fukushima Daiichi nuclear plant to enhance cooling efficiency, but highly radioactive water was later found leaking near all four troubled reactor units at the plant.

A day after three workers were exposed to water containing radioactive materials 10,000 times the normal level at the turbine building connected to the No. 3 reactor building, a water pool with similarly highly concentrated radioactive materials was found in the No. 1 reactor's turbine building, causing some restoration work to be suspended, it said.

Pools of water that may have seeped from either the reactor cores or spent fuel pools were also found in the turbine buildings of the No. 2 and No. 4 reactors, measuring up to 1 meter and 80 centimeters deep, respectively, while those near the No. 1 and No. 3 reactors were up to 40 cm and 1.5 meters deep.

http://english.kyodonews.jp/news/2011/03/81133.html

 

[elbows]

Analysis of the water at reactor 3 turbine building which workers were exposed to, some real nasty substances:

http://www.tepco.co.jp/en/press/corp-com/release/11032503-e.html

For example, according to another source cobalt-60 "is also produced as a by-product of nuclear reactor operations, when structural materials, such as steel, are exposed to neutron radiation."

 

[elbows]

This NYT story isnt very happy.

http://www.nytimes.com/2011/03/26/world/asia/26japan.html?pagewanted=1&_r=1

Just to focus on the most worrying part of this article:

Hidehiko Nishiyama, deputy director-general of the Japan Nuclear and Industrial Safety Agency, mentioned damage to the reactor vessel on Friday as a possible explanation of how water in the adjacent containment building had become so radioactive. A senior nuclear executive who insisted on anonymity but has broad contacts in Japan said that there was a long vertical crack running down the side of the reactor vessel itself. The crack runs down below the water level in the reactor and has been leaking fluids and gases, he said.

The severity of the radiation burns to the injured workers are consistent with contamination by water that had been in contact with damaged fuel rods, the executive said.

“There is a definite, definite crack in the vessel — it’s up and down and it’s large,” he said. “The problem with cracks is they do not get smaller.”

I believe I have read that the Japan Nuclear and Industrial Safety Agency subsequently backed away somewhat from their earlier comments about rector vessel damage. I have no way to judge the reliability of the 'senior nuclear executive' that NYT spoke to. And on page 2 some other 'expert' has a different theory. But regardless, even if this particular news goes unconfirmed or turns out to be wrong, I think this is still the sort of stuff we may well expect to come out in a confirmed way at some point.

 

[elbows]

There are some more site photos in this pdf:

http://www.nisa.meti.go.jp/english/files/en20110325-1-5.pdf

 

[southside]

One thing I find very suspicious about this is the fact the the media have reduced their coverage and I for one don't trust what we're being told. Also no one has even considered the fact that sea water is being used so where is it going? back into the sea where the delicate ecosystems are being contaminated? another thing that has astounded me is no one has reported the affect the gulf stream is having after some 15 days of radiation being pumped into the atmosphere, that is being carried on the gulf stream that incidentally stops in the UK and is part of the reason our weather is so changeable, our weather reporters don't really report the gulf stream here, ever. Looking back at WW2 the Japanese launched balloons that carried bombs to the USA using the gulf stream and although the accuracy wasn't really there some of the bombs did hit the main land this tells me that Euorope and the Americas if not the whole world will have some problems with radiation from Fukushima and it's probably being played down for obvious reasons.

 

[elbows]

Part of the reason the media reduced their coverage was because the pace of developments slowed, and no new exciting explosions that were captured on video became available. However, thats certainly not the whole story. The media have sometimes done a good job during this event, but as time has gone on I've been less and less impressed by some of the reporting or the amount of attention that important new details are not given. We are almost certainly suffering from information inhibitors on more than 3 levels. The company desires to downplay certain things. The Japanese government does too. And the international bodies such as IAEA, and the media gets bored, is sloppy, lacks necessary level of understanding, has lots of other world events to focus on, may be subject to editorial pressures, and some of the experts they have on have a variety of reasons for downplaying things. Throw in the fact that its likely the authorities & company dont know the complete picture either, and its no surprise that we may feel like we dont have a great sense of exactly what we are dealing with here.

On the other hand, there is probably not much point in getting too carried away with worst possibilities. The international spread of radiation has not received much attention really, but it gets mentioned here and there, it is acknowledged that detectable levels of radioactive contamination will be found all around the northern hemisphere. Weather reports do mention the gulf stream on a variety of occasions when it is strongly influencing our weather and some weather event looms that the weather reporters feel the need to try and explain. Anyway the point for now is that there hasnt been any data so far which would suggest we might have to deal with levels of radioactive pollution on anything like the scale we received in the uk from Chernobyl. Never say never, there are few certainties at this stage as far as Im concerned, but this issue isnt really on my radar at the moment. We are still learning the levels of radioactivity that the more immediate area is suffering from, and even in parts of Japan that are further away from the reactor it would probably be scaremongering to talk about the radioactive fallout in too strong a way, let alone describe UK contamination in such terms.

But certainly ever since the experts first came on the telly and mocked the idea that this disaster could be on a scale anything like Chernobyl, I have been unamused and unimpressed by the impression being given. There has been quite a lot of shit spoken by 'experts', especially in the early days, and this combined with the failure of answers to emerge to some very big questions, means you are not wrong to be suspicious. But as suspicion does not actually lead us to the facts, but only prepares us for the time when some hefty bad news emerges and our brains will think 'I knew it'. In the meantime I choose to busy myself looking at small geeky details to try to distract me from my impatience to learn the full details of what has happened. If I didnt enjoy geeking out on details then Id be mostly wasting my time, for none of these details has confirmed anything really important in my mind, they just hint at some of the possibilities. I think people can probably get just as good an idea what the possible realities are just by looking at the video of the explosions, the photos of the state of the reactor buildings, and the news about where radiation levels that are above legal levels have been detected, contamination of food stuffs and water.