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Fukushima Daiichi nuclear disaster

Japanese official drinks Fukushima water!

http://www.bbc.co.uk/news/world-asia-pacific-15533018

I think the BBC reporting of this is probably sloppy. I very much doubt this is water that has been used to 'hose down' the damaged reactors. Rather it is probably water that has been building up at the basement of reactor buildings 5 & 6, reactors which did not meltdown. So its not highly contaminated water that has been decontaminated and is then normally reinjeted into the reactors. It's slightly-contaminated groundwater that has been processed and then sprayed around the site. I mentioned this water a little while back because obviously some people are not happy that its been sprayed around the site, but its not the really bad water. I still wouldn't want to drink it though.
 
Cheers, I could probably have trimmed it down a bit more but I struggle to be brief at the best of times.

Anyways, potentially significant news has emerged. I haven't had time to find he best stories about this yet, but it appears that the gas system they put in & switched on for reactor 2 on October 28th has detected a gas which indicates nuclear fission has occurred recently. So they stuck a load of boron in to attempt to suppress any nuclear reactions that could be occurring in this reactor. Im not that shocked since reactor 2 has been of most interest to me for many months now. More in a bit when I get myself up to speed.
 
Here is an article as a starting point:

http://www.nytimes.com/2011/11/03/w...n-detected-at-fukushima-reactor-in-japan.html

Nuclear workers at the crippled Fukushima power plant raced to inject boric acid into the plant’s No. 2 reactor early Wednesday after telltale radioactive elements were detected there, and the plant’s owner admitted for the first time that fuel deep inside three stricken plants was probably continuing to experience bursts of fission.

The unexpected bursts — something akin to flare-ups after a major fire — are extremely unlikely to presage a large-scale nuclear reaction with the resulting large-scale production of heat and radiation. But they threaten to increase the amount of dangerous radioactive elements leaking from the complex and complicate cleanup efforts, raising startling questions about how much remains uncertain at the plant, the site of the world’s worst nuclear disaster since Chernobyl. The Japanese government has said that it aims to bring the reactors to a stable state known as a “cold shutdown” by the end of the year.
On Wednesday, the plant’s operator, the Tokyo Electric Power Company, said that measurements of gas from inside Reactor No. 2 indicated the presence of radioactive xenon and other substances that could be the byproduct of nuclear fission. The presence of xenon 135 in particular, which has a half-life of just nine hours, seemed to indicate that fission took place very recently.
 
A video of a recent drive round the site which is a good reminder of the sheer scale of the site and its facilities. Lots of the things they have put in place to cope with the disaster are on view, just look at the scale of the water storage facilities for a start.

 
The discovery of the noble gasses with the short half-life got hyped up when the company said they 'could not rue out re-criticality having taken place' and then everything got downplayed when they changed their mind and decided that its just a sign of some spontaneous fission, which is pretty normal. I'm keeping an open mind, but certainly I think we'd know about it if much in the way of large-scale re-criticality had occurred, I would expect far more heat to be generated for a start and for this to show up on various readings, which it didn't. But I don't rule out some more limited form of re-criticality having taken place occasionally, in this instance perhaps around October 25th-28th timeframe, though there isn't really strong evidence to support this, just a few weak pointers that I could be wrong about.
 
The dark comedic side of the story rears its head once more.

http://www3.nhk.or.jp/daily/english/20111117_28.html

An Environment Ministry official has dumped radiation-contaminated soil near his home in Saitama Prefecture, near Tokyo.

Environment Minister Goshi Hosono revealed this at a news conference on Thursday.

He said a cardboard box containing the soil was sent to his ministry on November 8th from a sender who identifies himself as a resident of Fukushima City.

An enclosed message calls on the ministry to store and dispose of the soil collected from the sender's garden.

The Environment Ministry kept the soil in its warehouse, and the radiation reading taken close to it was 0.18 microsieverts per hour.

A section chief at the ministry said this is no higher than readings taken in many areas in and around Tokyo and suggested he could dispose of the soil in his own garden.

His subordinate then dumped the soil in a vacant lot near his home on Sunday.

This was revealed after another box marked as "ash" was sent to the ministry apparently from the same sender on Wednesday.

The ministry is said to have already retrieved the soil and plans to dispose of it appropriately.

Hosono said he takes the inappropriate dumping of the soil very seriously and apologized. He said it should not have happened, as his ministry has been playing a central role in efforts to clean up areas contaminated with radiation.

Hosono said he will punish the section chief and study taking punitive actions against other senior officials, including himself.

He also said sending radiation-contaminated materials to his ministry will not lead to a fundamental solution to the problem, and called on people not to do so.

Thursday, November 17, 2011 18:41 +0900 (JST)
 
Another story about the rice:

http://www.japantimes.co.jp/text/nn20111117x1.html

Onami is about 80 km from the Fukushima No. 1 nuclear power plant.
Fukushima officials said the prefecture had examined earlier samples of rice from the area and didn't find cesium above the 500-becquerel threshold.
The contaminated rice was found when a farmer from Onami took unmilled rice to a local agricultural cooperative for inspection on Monday.
A more precise test Tuesday confirmed the high level of cesium.
Rice grown on the farm this year has not been shipped. The prefectural government on Wednesday requested farmers in the district to refrain from shipping their harvests.
After passing the initial tests, a total of 1 ton of rice from 86 farms among the 154 in the Onami district has already been shipped to local rice sellers, according to the prefecture.
To prevent tainted rice from making it to store shelves, Fujimura said, "the government will continue inspections as we had been doing before."
An official said the agriculture ministry will consider launching more efficient food inspections next year.
Meanwhile, Prime Minister Yoshihiko Noda will continue to keep eating rice harvested in Fukushima Prefecture at his official residence, Fujimura said.
Noda wrote in his official blog post last month that he began eating rice from Fukushima on Oct. 21, a few days after visiting the prefecture and promising the people there he would switch to Fukushima rice at the Prime Minister's Official Residence.
"I want to help even though it may do little to wipe away harmful rumors" about Fukushima agricultural products caused by the nuclear disaster, the blog entry says.
 
The manager of Fukushima has had to quit his post as he has been admitted to hospital. They won't say whats wrong with him, so its impossible to judge whether radiation may be a factor.

http://www.telegraph.co.uk/news/wor...ector-steps-down-suddenly-due-to-illness.html

The following news has come up before but Im not sure if we talked about it here so I will post it. TEPCO did a study in 2008 which warned that there was a risk of a tsunami that would reach heights beyond the previous assumed levels. But they didn't do anything about it, considering it unrealistic.

http://www.japantimes.co.jp/text/nn20111128x2.html

Meanwhile at the plant there have only been a few things to report recently. They have decided that they need to inject nitrogen into the reactor vessels to prevent the hydrogen ratio increasing to potentially explosive levels (in addition to injecting it into containment which they have already been doing for months). But it will take time to get this new injection stuff up and running, so in the meantime they have decided to reduce the amount of water being injected into the reactors, to increase the temperature a bit in order to generate more steam, which they think will help reduce the hydrogen risk.

In reactor 3 building they got a robot to clean some rails on the floor which are normally used as part of a system for opening a large containment hatch in the containment wall. They discovered rather high radiation levels (more than a Sievert/hr) when doing this on one part of a rail, and when performing a similar operation some days later they got more readings in this range.
 
As part of the gradual drip drip release of info by TEPCO, they & some other orgs had a workshop the other day where they used computer modelling to look at what may have happened to the melted fuel.

For reactor 1 the model suggests that all of the fuel melted through the reactor vessel, and then ate into the concrete below. They think it didn't get as far as the steel containment vessel, but as data isn't brilliant and its just a model, its hard to know how well this simulation reflects reality.

At reactors 2 & 3 it is thought that just over half of the fuel fell out of the reactor vessel, and didn't eat into the concrete so much.

http://www.nytimes.com/2011/12/01/world/asia/meltdown-in-japan-may-have-been-worse-than-thought.html

http://www.google.com/hostednews/af...ocId=CNG.017a81500c7adf1d02b69eed35946522.a01
 
From the Guardian

Fuel rods inside one of the reactors at the Fukushima Daiichi nuclear power plant may have completely melted and bored most of the way through a concrete floor, the reactor's last line of defence before its steel outer casing, the plant's operator said.

Tokyo Electric Power (Tepco) said in a report that fuel inside reactor No 1 appeared to have dropped through its inner pressure vessel and into the outer containment vessel, indicating that the accident was more severe than first thought.

The revelation that the plant may have narrowly averted a disastrous "China syndrome" scenario comes days after reports that the company had dismissed a 2008 warning that the plant was inadequately prepared to resist a tsunami.

Tepco revised its view of the damage inside the No 1 reactor – one of three that suffered meltdown soon after the 11 March disaster – after running a new simulation of the accident.

It would not comment on the exact position of the molten fuel, or on how much of it is exposed to water being pumped in to cool the reactor. More than nine months into the crisis, workers are still unable to gauge the damage directly because of dangerously high levels of radiation inside the reactor building.

"Uncertainty involved in the analysis is significant, due to the uncertain nature of the original conditions and data used," Tepco said in a report. It said the concrete "could have been penetrated", but added that the fuel remained inside the reactor's outer casing.

Previously, the firm had said that only some of the fuel had burned through its inner pressure vessel and dropped into the containment vessel.

"Almost no fuel remains at its original position," Tepco said. The simulation shows that the fuel may have penetrated the concrete floor by up to 65cm, just 37cm from the reactor's outer steel wall.

Tepco said that about 60% of the fuel in the two other reactors that experienced meltdown had dropped onto the concrete base, but had caused less damage.

After the tsunami, workers at the site stopped injecting reactor No 1 with water for about 14 hours, resulting in more serious damage than sustained by the two other reactors.

The company added, however, that fuel in all three reactors was being kept stable by cooling water, adding that the erosion had stopped.

It said the findings would not affect plans to bring the reactors to a safe state, known as cold shutdown, possibly by the middle of the month.

Japanese authorities may announce cold shutdown on 16 December, the Yomiuri Shimbun reported on Friday. That stage is reached when water used to cool the fuel rods remains below boiling point, thereby preventing the fuel from heating up again.

Stabilising the reactors is just the first stage of the operation to resolve the crisis. Tepco has said it won't be able to begin removing the fuel for another 10 years. Decommissioning the plant could take at least 30 years.
 
Cheers, although I should point out that I haven't attempted to post about many of the food contamination stories, only drawing attention to these matters when sporadically, mostly when a new class of foodstuff turns up with radiation for the first time. Cant even remember if I reported on the radioactive rice that started to be detected a while back. Quite how concerned people eating/drinking this stuff should be comes down to whether you believe there is a 'safe' level of contamination. But even before this powdered milk formula story, there have been numerous examples where reasonable steps to protect children from food & drink contamination have not been taken, e.g. school meals. Aspects of Japanese culture, corruption and governance have left them wide open to this sort of thing :( (not that any country is likely to be able to deal with a disaster on this scale 'perfectly', but even so)
 
I will review the visual 'evidence' in a bit.

But speaking generally, there were certainly concerns about the integrity of reactor 4 building and specifically the fuel pool (since all the fuel for 4 is in that pool as the reactor itself was undergoing some hardcore maintenance (shroud replacement) at the time of the disaster). So they built a steel structure inside the building, underneath the pool, to reduce the risk to the pool should another earthquake cause problems.

Its certainly true that if the pool collapsed and the fuel was scattered about/no longer shielded by water, it would be a major event and would at the very least make it hard for humans to be present on site. The fuel would get a bit hot and that could case a release into the wider atmosphere.

So really the key to this scaremongering story is what has actually happened to the building. They were performing debris removal in the upper areas of both reactors 3 & 4, and building 4 was already in bad shape, plus some complete chumps scare mongered months ago that 'reactor 4 was leaning' which was guff, so Im quite cynical right now, but I shall review the footage anyway just in case.
 
I have reviewed the footage. It looks very likely that they have neatly removed a damaged section of reactor 4 building roof and wall to the south. This stuff is above the pool and was not helping pool integrity, and it make sense to move it as the main risk was for it to fall into the pool. So that site is just a typical example of scaremongering idiocy where they don't even understand what they are looking at.
 
I have reviewed the footage. It looks very likely that they have neatly removed a damaged section of reactor 4 building roof and wall to the south. This stuff is above the pool and was not helping pool integrity, and it make sense to move it as the main risk was for it to fall into the pool. So that site is just a typical example of scaremongering idiocy where they don't even understand what they are looking at.
that makes perfect sense to remove damaged structure from around the reactor, that's why I bring it here, to get it cleared up. There's lots of scaremongering about, it's nice to get some perspective. (thanks again for entertaining the link)
 
I never mind doing that stuff, and sometimes the 'evidence' is interesting for completely different reasons to the scaremongering narrative. As long as you can live with me insulting those sites then carry on :D
 
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