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Meltdown Likely Under Way At Japan Nuclear Reactor


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NHK:

14 hospital patients die at emergency shelter

Fukushima Prefecture is looking into the deaths of 14 hospital patients at an emergency shelter where they had evacuated.

Prefectural officials say 128 hospital patients evacuated on Monday to a high school in Iwaki city. Two of them reportedly died en route on a bus, and 12 others died shortly after arriving at the shelter.

Most of the patients were elderly, and some bedridden. They were asked to stay at the shelter before being moved to another hospital.

The high school principal says there were 4 medical staffers at the shelter, but medical equipment has been in short supply. The patients were laid on a blanket on a tatami mat, with heaters placed nearby.

Thursday, March 17, 2011 08:35 +0900 (JST)

http://www3.nhk.or.j...lish/17_13.html

Edited by jfchandler
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NHK:

New power lines being planned for cooling system

The operator of the quake-damaged Fukushima Daiichi nuclear power plant says it is trying to install new power lines to reactivate its cooling systems in a desperate effort to stop the ongoing radioactive leakage.

Tokyo Electric Power Company says it wants to start the work to install the new lines as early as Thursday morning.

Emergency diesel power generators in the Fukushima Daiichi nuclear power plant failed to work because of a power blackout following the earthquake. They were also damaged by the ensuing tsunami.

The troubled diesel power generators caused the cooling systems to fail, which then affected the Number-1, -2 and -3 reactors. All the spent fuel rods housed in the 6 reactor buildings were also affected.

As a result, the rods remained hot and exposed above the surface of the coolant water. Damage and melting may have occurred.

The top priority at the moment is restoring the functions of the cooling systems now that radiation is continuing to leak from the plant.

Tokyo Power Electric Company says it is considering laying new power lines into the plant directly from cables of another power company. The company says it hopes to reactivate the cooling systems by connecting the cables to a makeshift switchboard and using them as an emergency power source for the systems.

But the company says it was unable to carry out the work on Wednesday because of high readings of radiation in the compound.

The company says it will try to complete the installation as soon as possible after reviewing the procedures in order to keep the workers' radiation exposure to a minimum.

Thursday, March 17, 2011 05:35 +0900 (JST)

http://www3.nhk.or.jp/daily/english/17_02.html

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If they pull this off, we're more or less out of the woods. The reactors themselves never really worried me much, as even a worst-case failure only means a very expensive site cleanup (contained melt-down).

The open storage pools are a big deal though IMHO, once they get power and circulation back to them, it will be safe.

Cleanup will be a long term operation though, I don't think anything at the Daiichi site will ever produce power again.

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NHK:

Japan calls on foreign countries to remain calm

Japan's Foreign Ministry has urged calm as some foreign governments have issued warnings against travel to Japan, or advised citizens already in the country to leave. The moves come amid the threat of seismic aftershocks and continuing leaks from the Fukushima nuclear power plant.

The governments of Iraq, Bahrain and Angola have notified the Foreign Ministry that they will temporarily close their embassies in Japan. Their staff are reportedly moving out of Tokyo.

The Foreign Ministry says the Panamanian government has transferred its embassy functions to Kobe, western Japan, and Austria has evacuated its ambassador and embassy officials to Kyoto, also in western Japan.

The ministry on Wednesday asked foreign diplomats and government officials in Japan to accurately convey information provided by Japanese authorities concerning the plant.

Wednesday, March 16, 2011 22:06 +0900 (JST)

http://www3.nhk.or.j...lish/16_47.html

Edited by jfchandler
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En route....so they say.

Am I the only one feeling some signs of optimism for the first time in days?

Always lots of hope, but I don't see much to be optimistic about yet. NHK saying 11 water cannon trucks enroute or on site.

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Will post a couple of items on nuclear explosion versus reactor explosion as the general public often equate the two as same-same.

Why A Nuclear Reactor Will Never Become A Bomb

By Alasdair Wilkins on March 17, 2011 at 10:14 AM

As Japan’s Fukushima power plant continues to struggle with massive equipment failure and radiation release that could well reach Chernobyl levels, we can take some small comfort in the knowledge that a full-on nuclear explosion is completely impossible. Here’s why.

Chain Reactions

Both nuclear reactors and nuclear weapons depend upon chain reactions. Such reactions require the presence of fissile materials, which are any atomic isotopes which can, when they undergo a particular nuclear reaction, create the raw materials necessary for the same reaction to repeat itself. There’s only one naturally occurring fissile isotope, and that’s uranium-235 – all other fissile isotopes, such as various plutonium isotopes, have to be artificially “bred” from natural isotopes.

So how does a chain reaction work? Let’s consider the one involving uranium-235, which is the chain reaction used in nuclear reactors and many nuclear weapons. A free neutron hits a slow-moving uranium-235 isotope and is absorbed into it. Here one of two things can happen: the uranium will fission into two lighter, faster-moving isotopes, typically krypton-92 and barium-141, as well as some gamma radiation. The nuclear reactor is then able to absorb this energy, which is about three million times the energy the same amount of coal can produce in conventional burning.

Crucially, this reaction also creates additional free neutrons, which can then be absorbed into other uranium-235 isotopes and start the whole process over again. This is why, of the naturally occurring uranium isotopes, only uranium-235 is fissile – when uranium-238 undergoes such reactions, it can’t release neutrons with the energy to start up a chain reaction.

As long as the reactions create an average of one or more neutrons, the chain reaction can go on indefinitely. Frequently, these reactions create more than one free neutron, which can cause the amount of energy being produced to increase over subsequent generations.

Source

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Can Japan's nuclear power plants explode like a nuclear bomb?

Thankfully, it is physically impossible for a nuclear power plant to explode like a nuclear bomb. It simply doesn't have the right kinds of materials: A fission bomb uses highly enriched uranium or plutonium (90%+ of U-235 or Pu-239), while a nuclear power station generally uses Uranium that is only enriched to around 5% (sometimes up to 20% in smaller research reactors). A nuclear power station also lacks all the other mechanisms that are necessary to create a nuclear explosion (like for example the implosion or gun-type assembly configurations that allow supercritical mass to be reached).

Mini-FAQ on Japans reactors

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Well, they've already put sea water into 3 or 4 of the reactors.. among 1-4... 5 and 6 still hanging out there...

For any individual reactor, sea water injection means that particular reactor is done.

ICleanup will be a long term operation though, I don't think anything at the Daiichi site will ever produce power again.

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Mar 14, 2011

Nuclear reactor explosion, not nuclear explosion

Posted in Science at 8:21 am by David Bradley

It is not skilful engineering or clever reactor design that precludes a nuclear explosion at a nuclear power plant, it is the laws of physics.

The materials in a nuclear reactor core and the uranium enrichment level make impossible a nuclear explosion of the type for which nuclear weapons are designed. Despite this, repeatedly we have heard talk of nuclear explosions in the media from observers, pundits, anti-nuclear activists and journalists.

An explosion at a nuclear reactor is not a nuclear explosion and can never be. Power plant grade uranium contains the fissile form of uranium, the uranium-235 isotope, at just a few percent, the majority is non-fissile U238. Compare that to weapons grade uranium which has to contain 80% or more of U235. Moreover, a nuclear weapon requires that a critical mass of the radioactive material be forced together quickly in a relatively small volume. This cannot happen in a nuclear plant, the low concentration of fissile U235 means it can never reach an explosively critical mass of fissile material but there is also no process that could force it together into a small volume quickly, anyway.

Sciencebase.com

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NHK:

Prime Minister Kan thanked the United Nations for sending its disaster specialists to Japan and for offering assistance to his country.

He emphasized the importance of sharing disaster information with other countries, saying his government will provide necessary information to the international community.

Thursday, March 17, 2011 08:29 +0900 (JST)

:

Edited by jfchandler
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NHK:

Govt asked about 500 missing foreigners

Japan's Foreign Ministry has received inquiries about 500 foreign nationals missing since Friday's earthquake.

The ministry said on Wednesday it is asking municipal officials, police, and fire departments in the damaged areas for any information they may have on the whereabouts of foreign residents.

The ministry also noted that some countries are urging their citizens to leave Japan or refrain from visiting due to the series of nuclear accidents in the disaster zone.

The ministry said it had asked these countries to accurately relay the information provided by the Japanese government about the earthquake and nuclear accidents, and respond calmly to the situation.

Wednesday, March 16, 2011 15:09 +0900 (JST)

http://www3.nhk.or.jp/daily/english/16_31.html

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NHK:

UK, France, Germany asking their nationals to leave

Foreign embassies are asking their nationals to evacuate Japan temporarily to avoid problems caused by the leaking nuclear power plant in Fukushima Prefecture.

On Wednesday, the British government asked Britons staying in Tokyo and the city's northern areas to consider leaving.

The Russian Foreign Ministry also announced on Wednesday that family members of its officials will leave Japan temporarily this week. The officials are working at the embassy, the trade representation in Tokyo and 3 consulates in Niigata, Sapporo and Osaka. The ministry has no plan to allow the officials to leave Japan.

The ministry calls on Russian nationals staying in Japan to act calmly and not depend on unreliable information.

On the same day, the German foreign ministry advised its nationals, who live in northern Japan and Tokyo metropolitan areas, to move toward Osaka or return home via Osaka. The ministry said the embassy will send its officials to its consulate general in Osaka to help Germans who want to evacuate Japan.

The French government has urged its citizens in Tokyo to move to western Japan or leave for their country.

The Croatian foreign ministry said it will temporarily move its embassy function from Tokyo to Osaka on Thursday.

Thursday, March 17, 2011 08:26 +0900 (JST)

http://www3.nhk.or.jp/daily/english/17_07.html

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NHK:

US military restricts activity within 90km

The US Defense Department says it has provisionally suspended activities of US forces engaging in rescue operations in northeast Japan within 90-kilometers of the Fukushima Daiichi nuclear power plant.

Pentagon spokesman David Lapan announced the decision on Wednesday.

The US military has dispatched 15 ships including the nuclear-powered aircraft carrier Ronald Reagan to aid Japan's disaster response efforts.

The spokesman says the measures are meant to prevent troops from being exposed to nuclear radiation.

Lapan also says in an exceptional case if troops were to operate within 90 kilometers of the stricken power plant, they would be given potassium iodine tablets to guard against possible acute radiation symptoms.

The US Navy revealed on Monday that low-level radioactive materials were detected on some of the helicopter crewmembers carrying out relief operations in northern Japan.

The US military has so far dispatched 2 fire engines to help Japan cope with a series of troubles at the plant, and it also says preparations are under way to send other equipment such as hoses and pumps to the plant.

Thursday, March 17, 2011 10:14 +0900 (JST)

http://www3.nhk.or.j...lish/17_14.html

Edited by jfchandler
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Here is some interesting reading about 'pool fires'

http://brc.gov/e-mails/September10/G_Thompson_WasteConfRpt09.pdf

The accident sequences that could result in water loss from the SFP, including beyond design basis earthquakes, various types of seal failures and dropped shipping casks, and the Zircaloy cladding fire issues have been studied by the NRC staff. The results of these studies are provided in NUREG-1353, “Regulatory Analysis for the Resolution of Generic Issue 82, Beyond Design Basis Accidents in Spent-Fuel Pools”.

Although these studies conclude that most of the spent-fuel pool risk is derived from beyond design basis earthquakes, this risk is not greater than the risk from core damage accidents due to these beyond design basis earthquakes. Therefore, reducing the risk from spent-fuel pools due to events beyond the safe shutdown earthquake would still leave a comparable risk due to core damage accidents. The risk due to beyond design basis accidents in spent-fuel pools, while not negligible, is sufficiently low that the added cost involved with further risk reduction is not warranted.

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Please include the links to your posts, James...

Guardian UK: UN forecast of movement of radioactive plume coming from Fukushima shows it possibly reaching CA on Friday,

it was a tweet from the Guardian - let me see if I can find it again and will add it in.

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NHK:

GE to send power generators to Japan

The US-based General Electric Company, or GE, will send 10 gas turbine generators to Japan to help replace power generating capacity lost when nuclear reactors were damaged in Friday's mega-quake.

GE said on Tuesday it was sending the generators on request from Tokyo Electric Power Company, which is struggling with a nuclear crisis at its Daiichi plant in Fukushima Prefecture. GE manufactured 2 of the plant's 6 reactors.

GE said 3 of the 10 gas turbine generators have been moved to Florida ahead of being flown to Japan.

The company said it is also offering technological assistance to Japan through a joint venture set up with Japanese electronics-maker Hitachi.

Wednesday, March 16, 2011 15:09 +0900 (JST)

Edited by jfchandler
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NHK:

Japan calls on foreign countries to remain calm

Japan's Foreign Ministry has urged calm as some foreign governments have issued warnings against travel to Japan, or advised citizens already in the country to leave. The moves come amid the threat of seismic aftershocks and continuing leaks from the Fukushima nuclear power plant.

The governments of Iraq, Bahrain and Angola have notified the Foreign Ministry that they will temporarily close their embassies in Japan. Their staff are reportedly moving out of Tokyo.

The Foreign Ministry says the Panamanian government has transferred its embassy functions to Kobe, western Japan, and Austria has evacuated its ambassador and embassy officials to Kyoto, also in western Japan.

The ministry on Wednesday asked foreign diplomats and government officials in Japan to accurately convey information provided by Japanese authorities concerning the plant.

Wednesday, March 16, 2011 22:06 +0900 (JST)

http://www3.nhk.or.j...lish/16_47.html

5555... Government officials want others to accurately convey information about the plants just as provided by them; while the IAEA and USNRC want those same Japanese officials to finally start conveying accurate and timely information about the crisis!

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Big lag in CNN's reporting. They're way behind. They are overly negative now. They need to access this thread guys.

Basically forget about being informed by any US based news station. They seem to exist solely to push their respective political stance.

Edited by Jdietz
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Please include the links to your posts, James...

Guardian UK: UN forecast of movement of radioactive plume coming from Fukushima shows it possibly reaching CA on Friday,

it was a tweet from the Guardian - let me see if I can find it again and will add it in.

Scientists Project Path of Radiation Plume

By WILLIAM J. BROAD

A United Nations forecast of the possible movement of the radioactive plume coming from crippled Japanese reactors shows it churning across the Pacific, and touching the Aleutian Islands on Thursday before hitting Southern California late Friday.

http://www.nytimes.com/2011/03/17/science/17plume.html?_r=1

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