Japanese reactor crisis

[AtLast]

My next door neighbor is a retired structural engineer (not nuclear) from PG&E (retired about a year after 35 years). Handy guy to have around. Anyway, he has worked on several nuclear reactors through the years and has been to Japan to see their reactors and attend conferences, etc. in his field while doing structural work on CA reactors. His areas of expertise are in metallurgy compounds and elemental structures (yup, sometimes, i just listen with my mouth open).

I ran into him this AM and asked him quite a few things, but the convo about how good it is that power is being returned to the plants and ER workers was interesting. he said if even some of the intrumentation in the plant control centers is working or can be fixed, so many of our questions could answered in terms of the actual damage inside the reactors- the containment vessels, especially. They have cameras throughout them. Other data could also finally be collected that can't be without the electrical systems working.

Then, TEPCO would have so much more info to put plans together- well, as long as the cooling continues to work.

He had lots to say about how newer plants designed after these (built in 1979) plants went online had many, many changes in those designs as well as how they are built- right down to cement mixing and rebar!! Obviously, the spent fuel arrangement at the Japan plants would not be done in the same way any longer.

Interesting conversation- Frank is super as a neighbor- has given me lots of tips for landcape and deck projects, plus helped me with getting my house's foundation (1940 bungalow) retro-fitted for earthquakes here in the SF Bay area.

just thought I'd share this. Aj has more of the goods on radiation- and Linus posted a chart. Thank!

[AtLast]

As always, media coverage is conflicting- re- CNN (Situation Room) just said Japanese governemnt widing evacuation zone- also might inpose mandatory evacuations in some areas. Yet, the continued down-play of radiation levels even with the mox mix.

NPR has blurb on why we we may never get full details.

http://www.npr.org/2011/03/25/134844...ed?ft=1&f=1001

March 25, 2011
The operators of the damaged Fukushima Dai-ichi power plant say it's likely that radiation detected in water pooling in the basement of a Unit 3 building came from the reactor's main vessel. This reactor has been the source of major concern since the March 11 earthquake and tsunami that devastated northern Japan, and led to the current crisis at the power facility.

Friday marks the two-week anniversary of the earthquake and tsunami that killed more than 10,000 people, and led to the crisis at the nuclear plant.

The announcement of the water leak raised concerns that the reactor core may have been breached. Officials later insisted that they have found no evidence of an actual breach in the reactor. There are many pipes and connections leading from the main vessel to the turbine building that could be the source of leaking water.

The water found in the turbine building of Unit 3 showed extremely high levels of radiation, and also contained isotopes that are not ordinarily present in cooling water.Since the accident began, there's been considerable speculation as to whether radiation leaks are coming from the reactors themselves or from spent fuel stored in pools that may have been damaged. This latest announcement is another indication that a leak is coming from the reactor itself. Highly radioactive water has also been found in the turbine buildings of Unit 1.

Japan Self-Defense Force officers in radiation protection suits hold a blue sheet over patients who were exposed high levels of radiation at the the Fukushima nuclear power plant as they are transferred to a hospital Thursday.

Japan Self-Defense Force officers in radiation protection suits hold a blue sheet over patients who were exposed high levels of radiation at the the Fukushima nuclear power plant as they are transferred to a hospital Thursday.

Injured Workers

The news of the leak comes a day after three workers were exposed to high levels of radioactivity while laying electrical cable in the basement of Unit 3's turbine building. Two of the men were taken to a local hospital for treatment of possible radiation burns. All three men were then brought to Japan's National Institute of Radiological Sciences in the Tokyo area.

The men worked for Kandenko Co, a electrical engineering firm doing subcontracting work for Tokyo Electric Power Co., or TEPCO. They are reported to be in good condition, and are expected to be released next week.

In a statement Friday, TEPCO, which runs the plant, indicated that the workers had ignored high readings on their dosimeters, which measure the presence of radiation.

The Nuclear Safety Commission of Japan also widened a voluntary evacuation area around the plant to a radius of about 18 miles from the nuclear plant. Since March 15, residents living within 12 miles have been urged to leave the area, and those living within the 18-mile range had been told to remain indoors.

Chief Cabinet Secretary Yukio Edano says local governments are being told to call for voluntary evacuations 18 miles out. The government said that the main concern was not radiation exposure, but that services in the area had been severely disrupted by the earthquake, tsunami and the nuclear crisis.

Mothers receive bottled water at a ward office in Tokyo, Friday, March 25, 2011 as the Tokyo Metropolitan Government started on Thursday to distribute three small bottles of water each to an estimated 80,000 families with babies of 12 months or younger

Mothers receive bottled water at a ward office in Tokyo, Friday, March 25, 2011 as the Tokyo Metropolitan Government started on Thursday to distribute three small bottles of water each to an estimated 80,000 families with babies of 12 months or younger.
The U.S. government previously had told its citizens to stay 50 miles away from the plant.

Food And Water Concerns

Radiation leaks have contaminated some food and water around the plant. Tokyo residents were warned on Wednesday that tap water had tested high for radioactivity, and that they should not allow infants to drink the water.

That order was rescinded the next day when readings dropped. But water systems in a number of cities continue to test above the levels considered safe for small children.

Japan has restricted the sale and consumption of vegetables, fruit and milk produced around the plant. And the United States and other countries have banned the import of some food products from the affected area.

Damage To Reactor Buildings

Japan's Self-Defense Forces released a video of the damaged reactor buildings, shot from a military helicopter. The film shows extensive damage to many of the buildings.

Despite these problems, officials continue to insist they are making progress in getting control of the six reactors at the Fukushima Dai-ichi plant. Work to revive the cooling equipment that lost power continues, officials say. External power has been restored to all six reactors. And the lights are coming back on in control rooms that have been dark and deserted for two weeks.

Technicians are also beginning to pump fresh water, instead of seawater, into Unit 1. TEPCO has been injecting seawater into some of the reactors to keep nuclear fuel from overheating, but there's concern that salt deposits from the seawater could make it more difficult to cool the fuel inside the reactors. The company plans to replace seawater with fresh water at Units 2 and 3, which have also suffered fuel damage.

Relief officials now say the confirmed death toll from the earthquake and tsunami has reached 10,000, with more than 17,000 people still missing. Hundreds of thousands of people are believed to be homeless, and the number of evacuees will now increase, with the government's decision to expand the safety zone around the plant.

With reporting from NPR's Jon Hamilton and Greg Dixon in Tokyo. Material from The Associated Press was also used in this report.

[AtLast]

The radiation levels leaking are an obvious concern- but this might explain why they are not able to get the core re-covered in water. Some claims of several cracks.

http://www.guardian.co.uk/world/2011...k-reactor-core

Japanese nuclear officials fear crack in reactor corePossible damage at Fukushima nuclear power plant could cause leak of high levels of radiation


Friday 25 March

Japanese people leave Minamisoma after the government told residents living near the Fukushima nuclear power plant to evacuate. Photograph: The Asahi

Nuclear safety officials in Japan fear the core of a reactor at the Fukushima Daiichi nuclear power plant may have cracked, causing a leak of high levels of radiation.

Growing uncertainty over the state of the stricken reactor prompted the government to tell people living within a 12-19 mile (20-30km) radius of the plant to consider leaving their homes temporarily.

The government's chief spokesman, Yukio Edano, said 130,000 residents in the area had been encouraged to leave to improve their quality of life, not because their health was at risk.

The nuclear emergency, 150 miles north of Tokyo, has caused severe disruption to business, supply routes and other services in the area.

On Thursday, three workers were exposed to radiation after stepping in contaminated water in the turbine building of the No 3 reactor. They were trying to cool the crippled reactor when the accident occurred.

"The contaminated water had 10,000 times the amount of radiation as would be found in water circulating from a normally operating reactor," said Hidehiko Nishiyama, a spokesman for Japan's nuclear safety agency. "It is possible that there is damage to the reactor."

Two of the men received possible beta ray burns to their legs. All three have been transferred to a special radiation treatment facility.

Edano said the source of the leak remained unknown. "We are exploring every possibility, but we don't think this is a new situation, rather that a certain amount of radiation may have leaked from the reactor. This is a possibility that we have been mentioning for some time.

"But at this point we don't know if the radiation is coming from the reactor itself or from another source."
Nuclear officials say the leak may have come from pipes or the reactor's pool for storing spent fuel rods, which workers have been struggling to cool off since the plant was badly damaged in the 11 March earthquake and tsunami.

Officials were preparing themselves for the possibility that the reactor core was damaged in an explosion three days after the disaster that destroyed its containment building. The reactor contains 170 tonnes of radioactive fuel in its core, and is the only one of the facility's six reactors that contains the potentially more dangerous plutonium-uranium mixed oxide fuel.

Thursday's accident forced a temporary halt to work on two reactors while technicians check radiation levels.

"We should try to avoid delays if at all possible, but we also need to ensure that the people working there are safe," Nishiyama said.

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I'm wondering (for Aj- or anyone that might know), if this is true, if the filling of the reactor as was done in Chernobyl with cenent and boron will be used?

The only resports I have heard about this being part of the reason the workers haven't been able to get the core covered with water due to these breaches (cracks) was on the Rachael Maddow Show this evening via one of her guests. Professor Frank Von Hippel, nuclear physicist and co-founder of the program on science and global security at Princeton University.



http://www.msnbc.msn.com/id/26315908/#42261008