Sea water has now been replaced with fresh water for cooling reactors, and, apparently, spent fuel storage pools. Work continues on restoring power and repairing cooling systems, but the cooling systems remain unrepaired. An interesting development overnight (overday in Japan): A very high radiation reading in Reactor 2 showed what apparently was high enough radiation to cause workers to immediately evacuate, as well as a high enough rate of short-lived radioactive isotope to make it a certainty that fission was happening, if not currently, within the previous few hours, and that radioactive stuff was leaking, according to the engineers, from the core.

Then, later, it was determined that the reading was a mistake. The person who took the reading ran away the moment the reading showed this high level. That may be because the workers who were injured in the radioactive “puddles” in Reactor 3 suffered those injuries in part because they did not believe the high readings they were getting. Policies and procedures were updated, we were told, so that would not happen again.

In the case of last night’s reading, however, it is normal that a second reading would be taken, but that did not happen because the first reading was so astoundingly high that, apparently, running away seemed to be the best thing to do.

At present, we don’t have any reports of new readings that are lower than the very high reading taken some time ago. What we have is the engineers deciding that the very high reading was too high to be believed. I’m not sure how to interpret that. Probably, it was just a bad reading.

Now that you have the necessary background, I give you Ana’s Feed and the usual links to recent news reports and commentary, as well as the International Atomic Energy Agency’s (IAEA) update. Ana is asleep right now, and has not heard about the retraction of the high reading.

Continue reading Japan quake, tsunami, nuke news 11 … overnight spike was false reading? →

A crack in the containment vessel of Fukashima Reactor 3 has been mentioned by MSNBC and ABC news, citing the New York Times. The New York Times has an article in which the crack is mentioned in a side bar, attributed to an anonymous person. An anonymous source is not particularly impressive, but the New York Time is. So I suppose this is somewhat impressive.

Various news sources are reporting an actual quote from the anonymous source and say a little more about him. This is what is being reported:
Continue reading The Crack at Fukushima Reactor 3, and other matters →

This is a particularly important update. An anonymous source in Japan has told reporters connected to the New York Times that there is a visible crack in the Fukushima Reactor 3. This is the reactor that showed isotopic evidence of a leak of some kind. Arguments had been made that a hole in the reactor vessel was an impossibility. The increasingly convincing evidence of a leak led people to admit, or realize, that the reactor vessel already has holes in it … those designed to allow pipes and such in and out of the large thick-walled metal object. It was then presumed that this is where leakage was happening, and that remains a distinct possibility. This presumption was based on the repeatedly stated impossibility of the reactor vessel being burned or corroded through.

But now we have evidence of a visible crack. A crack is a whole nuther matter. If there truly is a crack and the crack is through-and-through and allowing leakage, the we may be observing an excellent and disturbing example of how nuclear accidents often play out, and, in fact, why they happen to begin with. There have been repeated arguments made, in the press, on this blog (in comments), and elsewhere that there is no way that even melted down nuclear stuff inside the reactor vessel could eat its way through that vessel. Then a concession was made for pipe-holes. In the end, however, eating through the vessel or corroded or melted pipes may not be the point. Cracking the vessel then leaking out may be a possibility. Hadn’t been considered before.

There is isotopic evidence that the material leaking out of Reactor 3 is in part the product of fission that has occurred since shutdown of the machine at the time of the earthquake. This is not confirmed and there may be other explanations. But, if that is true, this probably means that fuel pellets have come free of their containment in fuel rods and accumulated somewhere in the reactor vessel in sufficient density to cause a chain reaction. If this has happened, it is probably not that severe of a chain reaction (or we would see more heat and other bad things). But, if there are fuel rods that have fallen apart, this means that future movement or pressure changes or other effects in the vessel could be more dangerous. Under some scenarios, just adding water can cause a brittle corroded fuel rod to fall apart, dropping more pellets into an accumulating pile of pellets lower down in the vessel.

Put metaphorically, the concentration of radioactive material in a mass that is increasingly close to that necessary to cause a chain reaction was dubbed, in the early days of nuclear research, “tickling the dragon’s tail.” Researchers, it is said, would move two piles of radioactive stuff closer and closer and measure the increase in radioactive output, in part to determine what a “critical mass” would be for that material. In theory, they would stop just before a high-level reaction occurred. Louis Slotin went to far with this technique in May, 1946 and it killed him.

If the isotopic evidence truly indicates that there has been post-quake fission in the reactor chamber, then this may mean that there is a dragon in there, metaphorically speaking We just have to hope that the Japanese engineers know how to keep the dragon calm.

There are other startling developments including a shakeup in the government. Ana has put together a very interesting feed. Read on:
Continue reading Japan quake, tsunami, nuke news 10 … Tickling the Dragon’s Tail? →

The water within Reactor Number 3 (where three workers were exposed to high levels of radiation yesterday) is 10,000 times more radioactive than the average water inside a nuclear reactor and contains radioactive iodine that is generated during fission and has a half-life of 8 days. Japanese engineers are pretty sure that this means that fuel rods within the reactor have contributed to fission reactions.

Here’s an important bit: The physical container that holds the fuel rods inside the reactor is very robust and is probably not leaking. However, as you might guess, the reactor container has a number of holes in it for pipes (etc.) that communicate between the inside and outside of the container. The reactor vessel need not be ruptured or broken for stuff to get out. The engineers in Japan think that highly contaminated water probably exited from the reactor containment via these pipes, though they are not sure.

There will be those who will claim that this does not constitute a leak. But it is.

Reactor containers 1 and 2 are also leaking, according to the engineers.

Source: NHK live report. You can also check the IAEA site for updates.

Regarding the workers (from the IAEA site):

Continue reading There is now little doubt that Fukushima Reactor 3 experienced post-tsunami fission but it is leaking →

Ana’s Feed starting at about 2PM Thursday 24 March:

Finally found some info on that simulation mentioned earlier: “…the model showed that areas where cumulative exposure over 12 days reached 100 millisieverts–the government’s maximum for infants–extended beyond the evacuation zone. A map based on data from the center showed areas that received a cumulative 100 millisieverts extended as far as about 40 kilometers northeast and south from the plant.”

Radiation 10,000 times normal level in water where nuke plant workers irradiated -kyodo news

• 1.3 million Bq of iodine 131. (NHK)
• Workers stood in 15cm of water – TEPCO says the day before, there were no puddles. (NHK)
• Safety agency has instructed TEPCO to revise and review their safety measures. (NHK)

There is very little being reported from Daiichi so far today, but here’s what I’ve gleaned :

• Lights are on in control room no.1. Temps. in the reactor reached 400C degrees. To cool, seawater was added and temp. dropped to 243C, but this increased pressure – the delicate dance of regulating temp. and pressure continues. (NHK)
• High levels of radiation in reactor no.2 are hampering work efforts. (NHK)
• Preparations are still underway to test the pump at reactor no.3. (NHK)
• No word on reactor no.4.
• White steam is seen rising from reactors 1-4. (NHK)

Cesium 137 was detected in mustard spinach in a field near Tokyo – 890Bq/kg (limit is 500). It was grown in a research plot and is not intended for consumption. (NHK)

Reactor vessel of Fukushima plant No. 3 unit may have been damaged: Gov’t panel -kyodo news … “The containment vessel is working to a certain degree” in reactor no.3, but it is leaking. -safety agency

Iodine 131 in water at 18 water purification plants exceeds the limit for infants. (NHK)

Edano: The government encourages those living in the 20-30km radius around the plant to move for easier living. (NHK)

• This statement was followed by something that sounded like there might be a future mandatory evac. order for this area, and perhaps beyond.
• “[1:15 a.m. ET Friday, 2:15 p.m. Friday in Tokyo] A Japanese official described the Fukushima Daiichi nuclear plant crisis as a “difficult” situation, and said the government will provide transportation to those seeking to evacuate with…in 30 kilometers. … Chief Cabinet Secretary Yukio Edano said authorities will provide transportation in response to growing demand among those living between 20-to-30 kilometers hoping to get farther away from the stricken plant.”(cnn live blog)

Police working to provide supplies to those in the evacuation zone have “suffered damages…to themselves.” They have asked for a resupply of uniforms, and for any protective equipment. (NHK)

South Korean water bottlers are diverting product from the domestic market, have amplified production, but still cannot meet Japanese demand. (NHK)

The 2 beta-burned workers have been transferred to the National Institute of Radiological Sciences. (NHK)

In which TEPCO confirms the presence of Zirconium 95 in seawater: http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110324e6.pdf

“It seems that somehow the containment function could have been compromised somewhat.” -safety agency briefing
Pressed by reporters on whether this is the case in all of the first 3, after a consult with men in the wings it is explained that given the reading of 500mSv in No.2 and also high readings in No.1, that similar things could be happening there, though the scale may be different.
Due to the spraying (necessary for avoiding total meltdown), water has accumulated in the basement-level turbine rooms (originally flooded by tsunami). Due to the containment leakages, this water cannot be worked in. On acknowledgement of this situation, a reporter asks “How will you proceed with the work?” The NISA spokesman says, “So far, we have not heard about how to proceed with the work.”
The 3rd contaminated worker, “with an abundance of caution,” has also been sent to hospital.
In the press briefing, the NISA spokesman is very careful to make clear that there is no confirmation of leaks/cracks in the containment, but that even so, “when we look at the composition of the water” it seems to have come form the core (it is more likely to have come from the core than the spent fuel area). Half an hour later, kyodo news reports that there is: No data suggesting No. 3 reactor core cracked: nuke agency

(Ana’s Feed is a collection of Analiese Miller’s facebook status entries posted as she takes in the news live in Japan.)

Links to news stories and updates:
Continue reading Japan quake, tsunami, nuke news 09 →

Ana’s Feed starting just after midnight 24 March:

“…estimates that 57,000 pounds of salt have accumulated in Reactor No. 1 and 99,000 pounds apiece in Reactors No. 2 and 3, which are larger.” (Editor’s note: This is what I had independently calculated, so it looks right to me)

Ban Ki-moon and IAEA and various governments are going to talk about ways to keep nuclear power safe. (NHK broadcast)

NHK is quoting the recent US poll that shows a decline in public opinion about nuclear power, adding “this means the American people are seriously responding to this situation in Japan.” (NHK)

Work at reactor no.3 has been suspended due to injury – 2 workers were exposed to ~170mSv, developed skin lesions on their feet and have been sent to hospital. (NHK)

The Tokyo metropolitan government is distributing mineral water to families with infants. (NHK)

“The challenges of radiological contamination have made this operation particularly difficult. It has required us to constantly watch the direction of the wind, to be mindful of where our forces are in relation to the Fukushima power plant. It has required us to monitor and decontaminate our aircraft, ships and even our people…”

Links to news stories and updates:
Continue reading Japan quake, tsunami, nuke news 08 →