8.8 earthquake hits Japan

The mice loved it.

The records show that the water of the Kitakami river in Miyagi Prefecture rose by 11 centimeters about 49 kilometers inland nearly 3 hours after the earthquake.

The Tone river rose by 30 centimeters at a point more than 44 kilometers from the estuary.

The ministry believes the waves would have reached further upstream if all the floodgates had been open. 6 of the 9 gates located 18 kilometers from the shore were closed when the tsunami hit one of Japan's longest rivers.

The plumbing leaks however do, and they're getting worse; some of that radioactive water tests at 1 Sv/hr and containment tanks and ditches are filling up fast. The robots have started arriving; there's electricity for remote monitors and batteries charges, but they have to be tethered to fiber-optic cables as radio wave communications are said to suffer interference from ambient radiation in the plant.

That datum worried me a bit - wouldn't it take runaway fission to produce so much interference? Even if things are so bad, why can't the robot operators switch to longer frequencies? There's got to be longer waves that get through any electromagnetic storm. Thanks for any information. Link and pictures:

http://www.technologyreview.com/computing/37164/page1/

All four have been equipped with fiber-optic tethers for communication, in case radio signals don't work in the plant's highly radioactive environment.

As for that "one sievert per hour" water, I hope that pumping it doesn't involve getting a human anywhere near it.

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PS HS, you should look up muromontite on the minerals data dot org site (called mindat). Its a very unique neutron generating 111/011 bifacial mineral where BeSiO8 is in direct contact w Uraninite . Whereever a lattice point of Be adjoins a U lattice point we have activity.The mineral is basically a neutron generator and then a reprocessor and Pu 244 source of . Its a fascinating mineral but, with all the apha around, its potentially a real killer. Most of it comes from Africa/Sweden and a teeny bit in US(That was my assignmentcough, cough)

I asked a health physicist friend about the pattern of Pu at Fukushma. She will look at some of the air data and soil data as it hits the web. If you find any of the soil data (as random walk or grid data) please post it up .K?

Hunt for Plutonium
Workers are still probing for the source of the plutonium found Monday at the Fukushima Daiichi nuclear plant.

Possible scenarios:
1. Some of the plutonium found is believed to have been there before the nuclear crisis started and is unconnected to the current situation. Tokyo Electric Power Co. says three of five samples are "equivalent to the fallout observed in Japan when the atmospheric nuclear test was conducted in the past."
2. Heating of spent fuel rods
A likely source of the plutonium, experts say. As it decays, uranium in fuel rods produces some plutonium, which might have been borne aloft by steam in spent-fuel containment pools, or in water that splashed out as workers doused the spent fuel rods to keep them cool.
3. Partial melting of fuel in reactors 1 or 2
Decaying uranium in the fuel rods of reactors 1 and 2 would also produce plutonium. A partial melting in No. 2 is already considered the likely source of the strong radiation readings there and could also account for the plutonium. However, experts say that if partially burned fuel accounted for the plutonium found on the site, radioactivity levels would likely be much higher than they now are
4. Partial melting of fuel in reactor No. 3.
Reactor No. 3's mixed-oxide, or MOX, fuel contains plutonium, and any breach in the reactor's containment unit might account for a plutonium release. Government and company officials say they don't have indications of such a breach, though, and experts say this is among the least likely scenarios.

...we detected the first arrival of the airborne fission products 131-I, 132-I, 132-Te, 134-Cs, and 137-Cs in Seattle, WA, USA, by identifying their characteristic gamma rays using a germanium detector. The highest detected activity to date is <~32 mBq/m^3 of 131-I.

Okay. No problem.

This is a much-abused word, but...awesome!

TEPCO chairman apologizes

The chairman of the Tokyo Electric Power Company has apologized for trouble and anxiety caused by radiation leaks from the Fukushima Daiichi nuclear power plant.

Tsunehisa Katsumata on Wednesday was speaking to reporters in Tokyo for the first time since problems at the plant surfaced. The firm's president, Masataka Shimizu, was hospitalized for hypertension and dizziness on Tuesday night.

Katsumata said he feels particularly sorry for local residents who've had to evacuate or refrain from going outside while coping with the impact of the quake and aftershocks.

Katsumata admitted that the company has not been able to cool the reactors, and pledged maximum efforts to stabilize them. He added that the No.1 through 4 reactors would eventually have to be shut down for good.

Katsumata also said his company is preparing to compensate in accordance with the law for damage caused by the radiation leaks.

The chairman apologized for the inconvenience caused by the company's rolling blackouts to cope with chronic power shortages since the March 11th quake and tsunami.

He said the company will do its best and work closely with the government to minimize or even avoid rolling blackouts this summer.

Wednesday, March 30, 2011 16:37 +0900 (JST)

Areva CEO arrives in Japan to help at Fukushima

The CEO of French nuclear reactor maker Areva says she will meet with Japanese officials to improve the situation at the quake-damaged Fukushima Daiichi nuclear power plant.

Speaking to an NHK reporter on her arrival at Narita Airport, near Tokyo, on Wednesday afternoon, Anne Lauvergeon pledged full cooperation. She brought along a team of experts, the first such group to arrive from France since the outbreak of the incident.

The Tokyo Electric Power Company and the Japanese government asked Areva -- one of the world's largest nuclear energy firms -- for technical support to remove highly radioactive water at the Fukushima plant. The contaminated water has hampered restoration work.

France is the world's second largest operator of nuclear power plants.

Soon after the accident in Fukushima, France sent Japan mobile radiation monitors, generators and protective clothing.

Wednesday, March 30, 2011 20:32 +0900 (JST)

Edano: Cover may be used to stop radiation

Japan's top government spokesman says the government and experts are considering whether to cover the reactor buildings at the Fukushima Daiichi nuclear plant with a special material, to stop the spread of radioactive substances.

Chief Cabinet Secretary Yukio Edano told reporters on Wednesday the experts are also examining the use of a tanker to collect irradiated water at the plant.

Edano said a variety of options are being studied to minimize radioactive contamination in areas around the plant, and to prevent health hazards.

He said working-level discussions are underway on the new measures and a political decision will probably be sought at some stage.

He said the whole situation is not at a point where he can responsibly say when the reactors will be brought under control. He said it will likely take a considerable amount of time before the fuel rods in the reactors and spent fuel pools cool down and stabilize.

Edano said monitoring for plutonium contamination may be extended to areas outside the plant compound since trace amounts of the element were found in soil on the plant grounds.

Edano said consumption and shipping restrictions on farm products will be lifted once their safety is consistently confirmed.

Wednesday, March 30, 2011 12:56 +0900 (JST)

In an article in The Guardian yesterday, Richard T. Lahey, former chair of nuclear engineering at Rensellaer Polytechnic Institute, in Troy, N.Y., was quoted as saying that the evidence he had seen indicated that fuel melted through the pressure vessel of reactor No. 2 at some point after the crisis began. He told The Guardian:

"The indications we have, from the reactor to radiation readings and the materials they are seeing, suggest that the core has melted through the bottom of the pressure vessel in unit two, and at least some of it is down on the floor of the drywell."

This morning, Lahey elaborated on his analysis for IEEE Spectrum, which he said had been accurately reported by The Guardian, but misinterpreted by some. (A careless read of the article suggests a new melt down at the plant, rather an analysis of what probably occurred early on in the crisis.)

Lahey says his analysis was based on the data sources seen by him and colleagues around the world, but that the information has been inconsistent and changes hourly. “It’s really hard to read the tea leaves,” Lahey says. “They keep blowing around… I may be wrong. I hope I’m wrong.”

However, his best take is that “all cores have melted, and it appears as though Unit 2 has melted through.”

His conclusion about reactor No. 2 comes largely from the amount of radiation in the water found there and the chemical contents of that water.

Flooding the building with sea water was the right move, he says. In a melt down, where the fuel escapes through the bottom of the chamber, the mix of molten metal—called corium, a buzzword for steel, uranium, zircolite, and other molten goop from the reactor—will vaporize the concrete and create dangerous radioactive aerosols. “The water will scrub out the radioactive aerosols” besides cooling the molten mass.

How long it will take to cool the corium beneath the vessel will depend on exactly how it escaped. If it melted a single big hole through the bottom of the vessel, it would pile up as a blob on the concrete. The blob’s low surface-area-to-volume ratio will make it hard to cool.

However, Lahey thinks there’s a chance that the corium escaped through narrow channels formed by the control rods, which in this type of reactor go all the way to the bottom of the vessel. In that case, the corium could have been extruded through the channels, forming something with more surface area.