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John Dolva

Nuclear power and Japan.

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This is indeed a disaster but you still have to remember:

This plant was about to be retired because it no longer met standards. It suffered through a huge earthquake and then a tsunami, and yet still didn't have a 'catastrophic' failure. The failure it is going through now is being caused by more than the 'worst case scenario': loss of power, loss of diesel generators, damage to water intakes, no backup power supplies, etc. And while I would indeed question the wisdom of placing nuclear power plants in a country / area that is guaranteed to be subjected to massive earthquakes, there are a multitude of other nuclear power plants in Japan that were closer / suffered the same forces and still successfully - and safely - shut down.

JAPAN_EARTHQUAKE_20110311.png

Nuclear power plants in Japan

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http://home.vicnet.n...%20Matters.html

Edited by John Dolva

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Australia's role in Japan’s nuclear fiasco

Sunday, March 20, 2011 By Jim Green

fukushima_koriyama_nuclear_radiation_march_16.jpg

Scanned for radiation: a temporary scanning center for residents living close to the quake-damaged Fukushima Daiichi nuclear power plant, March 16. There's every likelihood that radioactive by-products of Australian uranium have spewed into the atmosphere from the nuclear reactor plant at Fukushima in Japan.

BHP Billiton and Rio Tinto export uranium from Australia to Japanese nuclear company TEPCO from the Olympic Dam and Ranger mines.

Despite being a major uranium supplier to Japan, Australia has turned a blind eye to serious, protracted problems with Japan's nuclear industry. It is time for a more responsible approach.

See also: Australia's nuclear spin doctors

The earthquake on March 11 led to the automatic shutdown of the operating nuclear reactors at Fukushima.

However, TEPCO failed in its duty to maintain back-up electricity supply to run pumps to cool the intensely hot and radioactive nuclear cores. That, in turn, led to multiple fires, explosions and radiation releases.

Earthquakes have affected several nuclear plants in Japan. The most serious was the major 2007 earthquake that led to the shutdown of all of TEPCO's reactors at the Kashiwazaki-Kariwa plant in Niigata — not far from Fukushima, but on the west coast.

Radiation was released from two reactor buildings, from a pool containing spent nuclear fuel rods, and from 40 drums of nuclear waste that fell over and lost their lids.

There is a history of distrust surrounding TEPCO.

All of TEPCO's reactors were involved in a 2002 safety data falsification scandal, which led to protracted reactor shutdowns for inspections and repairs.

The “malpractices” were revealed to have been many and varied — and to have been ongoing for up to 25 years.

There have been many other incidents of data falsification involving reactors in Japan since the 2002 scandal. There have been further revelations about past incidents such as TEPCO's concealment of an emergency shutdown of one of the reactors at Fukushima in 1984.

Distrust of TEPCO grew as a result of the 2007 earthquake in Niigata. The company provided conflicting information over a period of several days,. It later acknowledged that the radiation releases would have been reduced if procedures were correctly followed.

Nuclear Engineering International reported: “Japan's nuclear industry has been suffering in the glare of negative publicity brought about by revelations that operators had covered up accidents and problems for decades.

“When it became public knowledge, it was hoped that the public relations disaster that companies were engineering for themselves might lead the wider industry to realise the potential benefits of being more open and honest when problems do crop up. That hope seems to have withered again in Niigata.”

A growing list of accidents are testament to the mismanagement of nuclear power in Japan. Some of the more serious accidents include:

· A sodium leak and fire at the Monju fast breeder plant in 1995.

· A reprocessing waste explosion at Tokai in 1997.

· Fifty tonnes of primary coolant leaked from a reactor at Tsuruga in 1999, leading to a sharp increase of radiation levels inside the reactor building.

· Following a criticality accident at a uranium conversion plant at Tokaimura in 1999, two people died and hundreds were irradiated.

· In 2001, a water pipe at Hamaoka-1 exploded, releasing radioactive steam into the containment building.

· In 2002, 16 workers were irradiated after a water pipe leak at Hamaoka-2.

· At the Mihama nuclear power plant in 2005, a pipe failed due to corrosion, resulting in the deaths of five workers and injuries to six others. The thickness of the failed pipe had not been checked since the plant went into operation in 1976.

A vicious cycle is evident. Mismanagement and slack regulation beget accidents and scandals. The authorities respond with denial and deceit, which later gives way to profuse apologies, resignation and solemn promises of improved performance in future.

Then it's business as usual — mismanagement and slack regulation beget the next accident or scandal. And the cycle repeats.

The pattern of mismanagement, accidents and scandals is reflected in public opinion. A 2005 survey by the International Atomic Energy Agency found that just 21% of Japanese citizens support the construction of new reactors; 76% are opposed.

Of the 18 countries surveyed, only four were more strongly opposed to the construction of new nuclear reactors.

As a major uranium supplier, Australia could play a role in breaking this vicious cycle by making uranium exports conditional on improved management of nuclear plants and tighter regulation.

Indeed, Australia has a responsibility to either insist on better performance or to cease uranium exports to Japan. The business-as-usual option makes us complicit in the ongoing fiasco of Japan's nuclear industry.

Australia is also complicit in fanning regional proliferation tensions by providing Japan with open-ended permission to separate and stockpile weapons-useable plutonium produced in power reactors from Australian uranium.

A 1993 US diplomatic cable posed these questions: “Can Japan expect that if it embarks on a massive plutonium recycling program that Korea and other nations would not press ahead with reprocessing programs?

“Would not the perception of Japan's being awash in plutonium and possessing leading edge rocket technology create anxiety in the region?”

Since 1993, Japan's plutonium stockpile has grown enormously and regional tensions are sharper than ever. Yet Australia continues to provide open-ended approval for Japan to stockpile plutonium.

It also continues to turn a blind eye to the pattern of accidents, scandals and cover-ups.

[Jim Green is the anti-national nuclear campaigner with Friends of the Earth, Australia.]

  • sharethis.png

From GLW issue 873

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''Radioactive water spilling into tunnels beneath Japanese nuclear plant; plutonium found in soil

The buildup of radioactive water in the tunnels underneath at least three reactors at the Fukushima Daiichi plant is hindering efforts to restore power to the facility. The discovery of trace levels of plutonium, which is highly carcinogenic, suggests that contaminated water has seeped into the nearby soil.''

http://www.latimes.com/news/nationworld/world/la-sci-japan-reactor-damage-20110328,0,7963192.story

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http://uk.reuters.com/article/2011/03/30/uk-japan-nuclear-impact-idUKLNE72T02R20110330

''Prolonged nuclear crisis carries big risks for Japan economy

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Quotes

Tokyo Electric Power Co Inc

9501.T

¥466

-100.00-17.67%

03/30/2011

By Linda Sieg

TOKYO | Wed Mar 30, 2011 11:42am BST

TOKYO (Reuters) - Nuclear experts can't agree what the worst-case scenario for Japan's nuclear crisis might be, so predicting the impact of the disaster on the world's third-largest economy with any accuracy is an impossible task.

But even if a catastrophic nuclear meltdown is averted, a drawn-out battle to stabilise the earthquake-crippled Fukushima plant poses a serious risk to an economy already burdened with huge public debt, an ageing population and a big bill to rebuild from a quake and tsunami disaster that caused damages possibly topping $300 billion.

"What is the worst-case scenario? Most people think it's a mushroom cloud. But the worst-case scenario is that this drags on, not one month or two months or six months, but for two years, or indefinitely," said Jesper Koll, director of equity research at JPMorgan Securities in Tokyo. "Japan will be bypassed. That is the real nightmare scenario."

Hundreds of engineers have been toiling for nearly three weeks to cool the plant's reactors and avert a meltdown of fuel rods, although that scenario seems to have become less likely.

"There is no 'best case' but the base case assumption is that things will be controlled and the long-term negative effects will be locally contained and won't affect the national economy -- and most importantly, the psyche of the people of one of the largest urban areas in the world," Koll added, referring to the capital of Tokyo with its population of some 13 million.

Fukushima plant operator Tokyo Electric Power Co (TEPCO) (9501.T) said on Wednesday that it would likely take a "fairly long time" to finally stabilise damaged reactors at the plant but company Chairman Tsunehisa Katsumata was unable to be more specific about the timeline.

That means, for now, the biggest threat for companies and consumers alike is uncertainty.

CONSUMER SPENDING AT RISK

A prolonged lack of clarity would add to pressure on Japanese firms to shift production overseas while further decreasing the attraction of Japan as an investment destination for foreign companies, already put off by the spectre of earthquakes, a strong yen and a sluggish economy.

The hollowing-out of Japan's economy has already seen overseas production rise to 20 percent of total output from 6 percent over the past two decades.

"It's not just companies outside Japan but companies in Japan that would become reluctant to make decisions to invest," said Takuji Okubo, chief economist at Societe Generale Securities in Tokyo.

Ironically, perhaps, that might help Japanese corporate profits if not the domestic economy.

"Japanese companies relocating faster overseas will increase profit margins, since overseas profit margins are three to five times higher than at domestic facilities," Koll said.

Simmering anxiety about the nuclear crisis and its impact on health through a spreading contamination of food and the atmosphere with radiation could also dampen consumer spending, economists said -- though, again, to what extent is difficult to gauge.

"Uncertainty is disliked by consumers and businesses," said Robert Feldman, chief economist at Morgan Stanley MUFG Securities in Tokyo. "The longer the uncertainty continues, the harder it is for demand to revive."

>2''

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http://www.commondreams.org/headline/2011/03/31

''Published on Thursday, March 31, 2011 by The Guardian/UK

Japan Says Battle to Save Nuclear Reactors Has Failed

Tepco says it has 'no choice' but to scrap reactors No 1-4, but hopes remaining two can continue to operate

by Justin McCurry in Tokyo Japanese officials have conceded that the battle to salvage four crippled reactors at the Fukushima Daiichi nuclear power plant has been lost.

japan_battletosave_failed.jpg

Damaged units at Fukushima Daiichi nuclear power plant, Japan. Japanese officials have conceded that the battle to salvage four crippled reactors at the Fukushima Daiichi nuclear power plant has been lost. (Air Photo Service/EPA) The plant's operator, Tokyo Electric Power (Tepco), said the reactors would be scrapped, and warned the operation to contain the nuclear crisis, well into its third week, could last months.

Tepco's announcement came as readings showed a dramatic increase in radioactive contamination in the sea near the atomic complex.

The firm's chairman, Tsunehisa Katsumata, said it had "no choice" but to scrap the Nos 1-4 reactors, but held out hope that the remaining two could continue to operate. It is the first time the company has admitted that at least part of the plant will have to be decommissioned.

But the government's chief spokesman, Yukio Edano, repeated an earlier call for all six reactors at the 40-year-old plant to be decommissioned. "It is very clear looking at the social circumstances," he said.

Tens of thousands of people living near the plants have been evacuated or ordered to stay indoors, while radioactive materials have leaked in to the sea, soil and air.

On Thursday, the International Atomic Energy Agency (IAEA) suggested widening the 30-km exclusion zone around the plant after finding that radiation levels at a village 40km from the plant exceeded the criteria for evacuation. ...''

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http://www.humaniteinenglish.com/spip.php?article1715

''Hidekatsu Yoshii: "Earthquake, Tsunami, Nuclear ... a Triple Shock for Japan"

Translated Friday 18 March 2011, by Henry Crapo and reviewed by Henry Crapo

Communist deputy in charge of the nuclear dossier for the Japanese Communist Party, Hidekatsu Yoshii considers that the arrogance of the private group Tepco has aggravated the lack of preparation in face of this natural catastrophe.

Huma: What is the outcome, up to now, of the earthquake and tsunami?

Hidekatsu Yoshii: Geographically, 20% of the national territory has suffered the effects of the catastrophe. About 520,000 persons have been evacuated. The number of dead and missing has been estimated, recently, at more than 11,500.

Huma: Has the Japanese government reacted rapidly enough and in an appropriate manner?

Hidekatsu Yoshii: Mobilization by the authorities has not at all met the expectations of the population. Neither Tepco, the electric company that exploits the generating plants in Fukushima, nor the government had imagined such a catastrophic scenario. They were not at all prepared for such a situation. Tepco kept saying they were convinced that the nuclear facilities were 100% safe. This multi-national company lived with a myth of absolute security. This arrogance aggravated the lack of preparation for this natural catastrophe.

Huma: How do evaluate the seriousness of this natural catastrophe? Is the comparison with Tchernobyl appropriate?

Hidekatsu Yoshii: After this earthquake of magnitude 9, all the nuclear facilities ceased to function. The reactors are shut down automatically. But that’s when the problems began, especially at the Fukushima Dai-ichi site, which is causing the problems today. Only reactors 1,2, and 3 were in service when the earthquake hit. Reactors 4,5,6 were in maintenance. But even when stopped, the nuclear fuel rods continue to give off heat. In this situation, if you do nothing, the temperature rises, with the danger of fusion in core of the reactor. You can’t manage without the cooling system. But the earthquake damaged the pump that feeds cooling water to the generating plant. As for the emergency relief system, it was put out of operation by the tsunami. The relief motor stopped, halting the secondary system for injection of cooling water. As a result, the fuel rods, out of the water, heated up, increasing the pressure. The technology used at Fukushima is very different from that at Tchernobyl. But left this way, the fuel bars in fusion in the core of the reactor can trigger incalculable consequences.

Huma: Can the earthquake and tsunami, alone, account for this nuclear catastrophe? Is the responsibility of the operating company also in question?

Hidekatsu Yoshii: From a geographic and geological point of view, we have experience with earthquakes. On this basis, we can pose questions as to the pertinence of construction of nuclear power plants in Japan. Tepco, and also the government of Japan, claimed to be convinced of the superiority of the technologies used. Together they maintained the myth of Japanese nuclear safety. The Japanese Commuist Party (PCJ), on the contrary, has always warned of the danger of earthquakes, and of the possible consequences in terms of nuclear safety. In the face of this argument, Tepco and the Japanese government have always placed their faith in existing rescue systems. But under the pressure of the tsunami, all the bolts came loose. It’s a long chain of failures that has led to this nuclear accident.

Huma: Tepco has a long history if concealing nuclear incidents. Has this multi-national company placed profit-making ahead of safety?

Hidekatsu Yoshii: Tepco reacted only after considerable delay in the accident that took place in 1999 in a ractor in Tokai-Mura, clearly in order to protect certain secrets. This culture of secrecy surrounds the electro-nuclear industry, and the opacity has become worse since 11 September 2001, in the name of the "War against Terrorism". Tepco was slow in giving us information. When pressure rose in the interior or the reactor, which made necessary the release of radioactive steam, they said and did nothing at first, fearful that an abnormal level of radioactivity would be detected. This is the reason for which they let the steam build up in the reactor to its upper limit. That’s what provoked the explosions. From the beginning Tepco has tried to conceal the malfunction of the cooling systems. Second problem, the company at first hesitated to inject sea water to cool the fuel rods, for fear of rendering them unusable. All these excesses and silences on the part of Tepco can be explained by their obsession with profitability. At every incident, every incident, they have lied to the population. But this time, there’s no escape. The responsibility of the enterprise is directly involved.

Huma: At this stage, what are the likely consequences for the population and for the environment?

Hidekatsu Yoshii: Earthquake, tsunami, nuclear catastrophe ... the human communities are today confronted by a triple shock. We have the experience of Hiroshima and Nagasaki. We know the dramatic impact of radiation on human beings, on nature, on agriculture. For all these reasons, the JCP calls for a progressive withdrawal from nuclear power generation, with a massive reinvestment in renewable energies.

Huma: How can Japan pick itself up after such a catastrophe? What sort of international solidarity is necessary?

Hidekatsu Yoshii: We have to aid hundreds of thousands of persons, who have lost everything, to reconstruct their lives. Already, the international community has shown great solidarity by sending teams of rescue workers and medical teams. We are very thankful to them. Then we will have to reconstruct the Japanese economy on new bases, with new energy policies, placing under control these multi-national companies, which act in an arbitrary fashion in search of maximum profits.''

http://news.xinhuanet.com/english2010/world/2011-03/31/c_13807189.htm''TOKYO, March 31 (Xinhua) -- Japanese Prime Minister Naoto Kan said on Thursday that the stricken Fukushima Daiichi (No. 1) nuclear power plant must be scrapped.

Kan made the remarks when meeting with the Japanese Communist Party (JCP) chief on Thursday.''

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http://www.guardian.co.uk/world/2011/apr/02/japan-fukushima-radioactive-water-leaking-sea

Radioactive water from Japan's quake-striken Fukushima Daiichi nuclear plant is leaking into the sea, its operator said.

The 20cm (8in) crack in a containment pit under reactor two may be the source of recent radiation in coastal waters, Tokyo Electric Power (Tepco) officials said.

Hidehiko Nishiyama, deputy director-general of the Nuclear and Industrial Safety Agency, said Tepco was planning to pour concrete into the pit to seal the crack, which may have been leaking since the magnitude 9.0 earthquake three weeks ago.

"This could be one of the sources of seawater contamination," Nishiyama said. "There could be other similar cracks in the area, and we must find them as quickly as possible."

----------------

http://www.greenpeace.org/usa/en/news-and-blogs/campaign-blog/new-greenpeace-report-analyzes-radiation-amou/blog/33949

A new analysis prepared for Greenpeace Germany by nuclear safety expert Dr Helmut Hirsch shows that by March 23 2011, Japan’s nuclear crisis has already released enough radioactivity to be ranked at Level 7 on the International Nuclear Event Scale (INES). This is the scale’s highest level, and equal to the 1986 Chernobyl nuclear disaster. Hirsch’s assessment, based on data published by the French government's radiation protection agency (IRSN) and the Austrian governments Central Institute for Meteorology and Geodynamics (ZAMG) found that the total amount of radionuclides iodine-131 and caesium-137 released between March 11 and March 23have been so high that the Fukushima crisis already equates to three INES 7 incidents.

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''

Japan's nuclear crisis: Week 4

April 05, 2011

control-room-for-unit-1-of-the.jpg Control room for unit 1 of the Fukushima Daiichi nuclear power plant. ©TEPCO

Enlarge image Greenpeace expands radiation team to investigate Fukushima fallout.

Greenpeace today announced the resumption of its radiation monitoring outside the evacuation zone (1) surrounding the stricken Fukushima nuclear complex (2). Adding a second field team of radiation experts, the investigation into the health threats to the local population will offer food tests of milk and vegetables.

Last week, Greenpeace called on the Japanese government to evacuate the contaminated areas outside the official zone, after confirming the authorities radiation data for the town of Iitate, where staying for just a few days could mean exposure to the annual allowable dose of radiation (3).

“More then three weeks have passed since the tsunami wreaked havoc at the Fukushima nuclear complex, yet the official response to the radiation risk continues to be sporadic and contradictory, leaving local populations confused and at risk. We hope to be able to provide independent analysis and clear advice to effected populations,” said Rianne Teule, Greenpeace International radiation expert. “ It’s crucial for people here to be kept informed, and for their voices to be heard; this will make it harder for the operators, the government and the international nuclear industry to keep playing down the consequences of this disaster. Those responsible for this crisis must take responsibility for protecting the affected populations, and for ensuring that people are properly compensated for the destruction of their livelihoods”.

“People need to be put before politics and business, no matter where contamination is found. If the radiation levels pose a serious risk to the population, then people should be protected and evacuated.”

“Nuclear power has no place in a modern safe and secure energy system. Japan must take last week’s statement (4) on making renewables a part of reconstruction a step further, and commit to a future based on energy efficiency and renewable energy, by dropping plans for nine new nuclear reactors by 2020.”s

Radiation dosage chart

Our Q and A on the Fukushima nuclear crisis

Read our latest blog

NOTES

(1) A detailed and annotated Google map of locations and radiation eadings compiled by the Greenpeace team can be found here http://bit.ly/gaMGnf

The current official evacuation zone is 20km round Fukushima, while between 20km and 30km is an area where people re advised to stay indoors or evacuate voluntarily.

(2) Greenpeace will have two small field teams carrying out radiation easurements, based in Yonezawa, but operating close to the Fukushima vacuation area. One team will focus on a survey to map surface ontamination and the other will focus on food & milk testing.

Greenpeace is making requests through Japan’s media for food producers and consumers volunteering their food to be tested, which may aid them n future compensation claims.

As part of the monitoring work, the team will be using a selection of standard radiation monitoring equipment:

- Gamma spectrometer: Exploranium GR-135 LB 200 Becquerel monitor

- Geiger counters: Radex RD 1503, RadAlert

- Contamination monitors: RADOS MicroCont, Berthold UMO

Lead by Rianne Teule, Greenpeace International Energy Campaigner and radiation expert, the teams include Greenpeace Germany Climate and energy Unit Head Thomas Breuer, Greenpeace International radiation safety expert Jan van de Putte, and Greenpeace International Logistics manager and qualified radiation safety advisor, Nikki Westwood.

More detailed biographies including other members can be found here:

http://t.co/sHYVSuy

(3) The team measured radiation of between 7 and 10 micro Sievert per hour in the town of Iitate, on Sunday March 27th, 40km northwest of the crisis-stricken Fukushima/Daiichi nuclear plant, and 20km beyond the official evacuation zone. These levels are high enough to require evacuation.

The levels detected refer to external radiation, and do not take into account the further risks such of ingestion or inhalation. The maximum allowable accumulated annual dose for members of the public is 1000 micro Sieverts.

The Fukushima Prefectural Government has been measuring the radiation evels in the same village and confirming even higher range of radiation level during the past two weeks.

http://www.pref.fukushima.jp/j/20-30km18.pdf

(4) “Gov't to push for solar energy in quake reconstruction plan: Edano”

http://english.kyodonews.jp/news/2011/03/81780.html

''

http://www.greenpeace.org/australia/news-and-events/news/nuclear-power/japan-s-nuclear-crisis-week-4

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Zengyoren, the Fishermens Union of Japan, demands the closure of all nuclear power plants in Japan. (Nikkei newspaper)

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Published by the International Committee of the Fourth International (ICFI)

http://www.wsws.org/articles/2011/apr2011/japa-a07.shtml

''US report points to serious dangers at Japanese nuclear plant

By Peter Symonds

7 April 2011

A confidential assessment of the Fukushima nuclear disaster drawn up by the US Nuclear Regulatory Commission (NRC) paints a far bleaker picture than the limited, sanitised reports being made public by the plant operator, Tokyo Electric Power Company (TEPCO) and Japanese nuclear authorities. The American document has not been publicly released but was leaked to the New York Times, which published some details on Tuesday.

Three of the six reactors at TEPCO’s Fukushima Daiichi plant were seriously damaged by overheating after their cooling systems failed during the March 11 earthquake and tsunami. In a desperate attempt to prevent a meltdown, TEPCO initially poured salt water into the primary containment vessels of the three reactors and also spent fuel rod pools that were in danger of overheating. Hydrogen gas produced by the oxidation of the zirconium cladding around reactor fuel rods led to a series of explosions that badly damaged reactor buildings.

Current reports from TEPCO, Japan’s nuclear regulator and the International Atomic Energy Agency (IAEA) provide little more than day-by-day updates on measures implemented, together with the temperatures and pressures of the three damaged reactors, and some readings of radioactivity in the land and sea around the site. The NRC document, however, points to the ongoing and possible dangers that are clearly being discussed behind closed doors in Japan and internationally.

Among the risks identified by the NRC are:

* There is the possibility of further explosions caused by hydrogen produced inside the damaged reactor cores that has the potential to rupture the primary containment vessels enclosing the cores. The NRC recommended the injection of nitrogen, an inert gas, into the containment vessels to try to purge them of accumulated oxygen and hydrogen.

* Fresh water is now being injected continuously into the containment vessels of reactor units 1, 2 and 3 in order to cool the reactor cores, but this process has the potential to compromise these vessels. The report warned “when flooding containment, consider the implications of water weight on seismic capability of containment”. In other words, the stress created by the huge weight of water could make the vessels more prone to damage in the event of aftershocks. Former General Electric reactor designer Margaret Harding told the New York Times: “If I were in the Japanese’s shoes, I’d be very reluctant to have tons and tons of water sitting in a containment whose structural integrity hasn’t been checked since the earthquake.”

* The NRC report recommended the addition of boron to the cooling water being pumped into the reactor cores. Boron acts as a moderator, that is, it absorbs neutrons and can be used to shut down the nuclear fission process inside reactor cores. This function is normally performed by control rods that are inserted directly into the reactor core. Engineers who prepared the NRC report emphasised to the New York Times that the proposal was a precaution and that there was no evidence of sustained nuclear fission, also known as criticality. The recommendation does, however, indicate both the danger of criticality and serious concerns over the extent of damage to the reactor cores, which at this stage can only be estimated.

* The spent fuel rod pools associated with reactor units 1, 2, 3 and 4 are a further danger. At the end of their useful life, fuel rods are removed from the reactor core and placed in cooling pools for a lengthy period. The initial hydrogen explosions may have been caused because water drained out of the pools, the rods overheated—damaging the zirconium cladding—and hydrogen was generated after the pools were flooded with salt water. Unlike the reactor cores, the spent fuel rod pools are not protected by extensive shielding and are now exposed to the atmosphere in the damaged reactor buildings.

The New York Times added: “The document also suggests that fragments or particles of nuclear fuel from the spent fuel pools above the reactors were blown ‘up to one mile from the units,’ and that pieces of highly radioactive material fell between two units and had to be ‘bulldozed over,’ presumably to protect workers at the site. The ejection of nuclear material, which may have occurred during one of the earlier hydrogen explosions, may indicate more extensive damage to the extremely radioactive pools than previously disclosed.”

The NRC report has been regularly updated since it was produced on March 26, but, according to the New York Times, the original version still reflected current thinking among the nuclear experts involved.

Union of Concerned Scientists (UCS) scientist David Lochbaum, who was not involved in the report, told the newspaper that the document revealed serious ongoing problems. “I thought they were, not out of the woods, but at least at the edge of the woods,” he said. “This paints a very different picture, and suggests that things are a lot worse. They could still have more damage in a big way if some of these things don’t work out for them.”

Yesterday, more than a week after the NRC report was drawn up, TEPCO announced that it was preparing to pump nitrogen into the containment vessel of Unit 1. TEPCO officials played down the dangers, declaring it was only a precaution. Hidehiko Nishiyama, spokesman for Japan’s Nuclear and Industrial Safety Agency (NISA), told a press conference there was “no immediate risk of a hydrogen explosion occurring.”

Yet a NISA engineer speaking anonymously to the Wall Street Journal explained that the risk of a hydrogen explosion could increase as the reactor core cooled and the pressure inside the containment vessel dropped, drawing in air from outside. The containment vessels were meant to be airtight but some of the vents and pipes running into and out of the reactor were believed to be damaged, he said, and could thus allow air to seep in, creating conditions for a hydrogen explosion.

The reassurances offered by TEPCO and NISA are highly questionable given that the condition of the containment vessels and the cores of three reactors is not known with any precision. TEPCO has said that 70 percent of fuel rods in the core of reactor 1 are damaged, as well as 20-30 percent of fuel rods in reactors 2 and 3. However, even if these estimates are accurate, the state of the fuel rods is only one element of the complex problem in fully stabilising the reactors.

The NRC assessment pointed to the danger that the initial use of saltwater to cool the reactor cores may have led to deposits of salt and blocked the circulation pathways, particularly in reactor 1. The report stated that water flow in that reactor “is severely restricted and likely blocked.” Inside the core itself “there is likely no water level” and therefore “it is difficult to determine how much cooling is getting to the fuel.” Similar, though less severe, problems probably affected reactors 2 and 3 as well. The switch from salt water to fresh water last week may have eased the dangers by washing away some of the salt, but the actual situation was not known.

None of the dangers identified by the NRC assessment has been aired by TEPCO, NISA or indeed by the IAEA—the international nuclear regulatory body. The very fact that the NRC document has not so far been made public points to a conspiracy of silence aimed at playing down the extent of the Japanese nuclear disaster and ongoing dangers, so as to allow business as usual in a highly profitable industry.''

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http://blog.earth-touch.com/nature-news/tsunami-flotsam-wheres-it-all-going/''California’s sunny beaches could get pretty messy in about three years as floating debris generated by Japan’s tsunami washes ashore.

When last month’s tsunami hit Japan’s coastal towns, it destroyed almost everything in its path – and much of the resulting debris was sucked back into the ocean when the massive wave receded. So where is all this gareki (debris in Japanese) drifting to? Thanks to a projection by scientists from the University of Hawaii, we have some idea of its future course.''

http://iprc.soest.hawaii.edu/users/nikolai/2011/Pacific_Islands/Simulation_of_Debris_from_March_11_2011_Japan_tsunami.gif

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..nan ne

houjin ko..

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