tagged w/ Ban Nuclear Power Plants
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The New York Times
PART ONE...
April 5, 2011
U.S. Sees Array of New Threats at Japan’s Nuclear Plant
By JAMES GLANZ and WILLIAM J. BROAD
United States government engineers sent to help with the crisis in Japan are warning that the troubled nuclear plant there is facing a wide array of fresh threats that could persist indefinitely, and that in some cases are expected to increase as a result of the very measures being taken to keep the plant stable, according to a confidential assessment prepared by the Nuclear Regulatory Commission.
Among the new threats that were cited in the assessment, dated March 26, are the mounting stresses placed on the containment structures as they fill with radioactive cooling water, making them more vulnerable to rupture in one of the aftershocks rattling the site after the earthquake and tsunami of March 11. The document also cites the possibility of explosions inside the containment structures due to the release of hydrogen and oxygen from seawater pumped into the reactors, and offers new details on how semimolten fuel rods and salt buildup are impeding the flow of fresh water meant to cool the nuclear cores.
In recent days, workers have grappled with several side effects of the emergency measures taken to keep nuclear fuel at the plant from overheating, including leaks of radioactive water at the site and radiation burns to workers who step into the water. The assessment, as well as interviews with officials familiar with it, points to a new panoply of complex challenges that water creates for the safety of workers and the recovery and long-term stability of the reactors.
While the assessment does not speculate on the likelihood of new explosions or damage from an aftershock, either could lead to a breach of the containment structures in one or more of the crippled reactors, the last barriers that prevent a much more serious release of radiation from the nuclear core. If the fuel continues to heat and melt because of ineffective cooling, some nuclear experts say, that could also leave a radioactive mass that could stay molten for an extended period.
The document, which was obtained by The New York Times, provides a more detailed technical assessment than Japanese officials have provided of the conundrum facing the Japanese as they struggle to prevent more fuel from melting at the Fukushima Daiichi plant. But it appears to rely largely on data shared with American experts by the Japanese.
Among other problems, the document raises new questions about whether pouring water on nuclear fuel in the absence of functioning cooling systems can be sustained indefinitely. Experts have said the Japanese need to continue to keep the fuel cool for many months until the plant can be stabilized, but there is growing awareness that the risks of pumping water on the fuel present a whole new category of challenges that the nuclear industry is only beginning to comprehend.
The document also suggests that fragments or particles of nuclear fuel from 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.
David A. Lochbaum, a nuclear engineer who worked on the kinds of General Electric reactors used in Japan and now directs the nuclear safety project at the Union of Concerned Scientists, said that the welter of problems revealed in the document at three separate reactors made a successful outcome even more uncertain.
“I thought they were, not out of the woods, but at least at the edge of the woods,” said Mr. Lochbaum, who was not involved in preparing the document. “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.”
CONTINUED...The New York Times
PART ONE...
April 5, 2011
U.S. Sees Array of New Threats... more
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CNN...
Jimmy Carter's exposure to nuclear danger
By Arthur Milnes, Special to CNN
April 5, 2011 6:50 p.m. EDT
Former President Carter attends a dedication ceremony for a nuclear submarine bearing his name April 27, 1998.
STORY HIGHLIGHTS
President Jimmy Carter was trained to work in the Navy's atomic energy program
Arthur Milnes says he was lowered into damaged nuclear reactor in Ontario in 1952
He says Carter's experience was similar to that of workers at Fukushima plant in Japan
Carter was exposed to high levels of radiation, Milnes says
Editor's note: Arthur Milnes, an award-winning Canadian journalist, is the Inaugural Fellow in Political History at Queen's University Archives in Kingston, Canada and the editor of "Jimmy and Rosalynn Carter: A Canadian Tribute" (2011 McGill-Queen's University Press and the Queen's School of Policy Studies ). He can be reached at arthur.milnes@sympatico.ca
Kingston, Ontario, Canada (CNN) -- Though Georgia is a continent and an ocean away from the Fukushima Daiichi nuclear plant, we can be confident that an 86-year-old man in that state knows full well the fears the Japanese cleanup crews are experiencing.
The Georgian's name? James Earl Carter, the 39th president of the United States. Almost 60 years ago, and then a young U.S. Naval officer working at the dawn of the nuclear age with the U.S. atomic submarine program, Carter was physically lowered into a damaged nuclear reactor in Chalk River, Ontario, Canada, and exposed to levels of radiation unthinkable today after an accident.
"We were fairly well instructed then on what nuclear power was, but for about six months after that I had radioactivity in my urine," President Carter, now 86, told me during an interview for my new book in Plains in 2008. "They let us get probably a thousand times more radiation than they would now. It was in the early stages and they didn't know."
Despite the fears he had to overcome, Carter admits he was animated at the opportunity to put his top-secret training to use in the cleanup of the reactor, located along the Ottawa River northwest of Ottawa.
"It was a very exciting time for me when the Chalk River plant melted down," he continued in the same interview. "I was one of the few people in the world who had clearance to go into a nuclear power plant," he said.
"There were 23 of us and I was in charge. I took my crew up there on the train."
On December 12, 1952, the NRX research reactor at Chalk River Laboratories suffered a partial meltdown. There was a power surge and as a result some fuel rods melted after rupturing. Millions of liters of radioactive water ended up in the reactor building's basement. The crucial reactor's core was left unusable. It was later rebuilt and worked for decades before its retirement in the early 1990s.
At the time, Carter was based in Schenectady, New York, and working closely with Adm. Hyman Rickover on the nuclear propulsion system for the Sea Wolf submarine. He was quickly ordered to Chalk River, joining other Canadian and American service personnel.
When he was running for president in 1975-76, Carter briefly described this experience in his book, "Why Not the Best?"
"It was the early 1950s ... I had only seconds that I could be in the reactor myself. We all went out on the tennis court, and they had an exact duplicate of the reactor on the tennis court. We would run out there with our wrenches and we'd check off so many bolts and nuts and they'd put them back on. ...
And finally when we went down into the reactor itself, which was extremely radioactive, then we would dash in there as quickly as we could and take off as many bolts as we could, the same bolts we had just been practicing on. Each time our men managed to remove a bolt or fitting from the core, the equivalent piece was removed on the mock-up."
Atomic Energy of Canada, a Crown corporation owned by the federal government in Ottawa, still operates nuclear facilities at Chalk River today but the aging systems have caused political controversy in Canada in recent years.
Carter biographer Peter Bourne, a close friend and adviser to Carter, believes the Chalk River experience had a lasting impact on the president, influencing him when he had to confront nuclear issues while leading the western alliance.
"My sense is that up until that point in his career, (Carter) had approached nuclear energy and nuclear physics in a very scientific and dispassionate way," he told me in a separate interview.
"The Chalk River experience made him realize the awesome and potentially very destructive power he was dealing with. It gave him a true respect for both the benefits but also the devastatingly destructive effect nuclear energy could have. I believe this emotional recognition of the true nature of the power mankind had unleashed informed his decisions as president, not just in terms of having his finger on the nuclear button, but in his decision not to pursue the development of the neutron bomb as a weapon."
In his 1995 foreign policy memoir (co-authored by Ivan Head), "The Canadian Way," the late Canadian prime minister, Pierre Trudeau -- in office from 1968 to 1979 and 1980-1984 -- made it clear that fellow world leaders had great respect for Carter on nuclear and non-proliferation issues due to his pre-White House work in the nuclear field.
In his inaugural address, Carter said he would work towards the goal of ridding the Earth of nuclear weapons, and it is a quest he continues today as a former president.
While in the White House, Carter signed the SALT II nuclear arms limitation agreement with the Soviet Union. According to his memoir, "Keeping Faith," he also asked that Vice President Walter Mondale receive full briefings on his possible role in a nuclear exchange and was shocked to learn that no previous second-in-command had been so informed. "It was obvious to me that ... the president might be incapacitated and (the vice president) had to be fully qualified to assume his duties."
As the Japanese workers struggle in their dangerous work, there's no doubt Jimmy Carter's thoughts and prayers have been directed their way. Unlike most of us, he truly understands their fears.
The opinions expressed in this commentary are solely those of Arthur Milnes.CNN...
Jimmy Carter's exposure to nuclear danger
By Arthur Milnes, Special... more
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The New York Times...
Higher Radiation Levels Found at Japanese Reactor
Carlos Barria/Reuters
Family members of the earthquake and tsunami victims at a mass funeral of their relatives on Saturday in Kesennuma, Japan.
By DAVID JOLLY and HIROKO TABUCHI
Published: March 27, 2011
TOKYO — Japanese officials continued to battle a spreading contamination problem at the Fukushima nuclear complex on Sunday, saying that water pooling inside one of its reactors and the seawater just outside the plant were showing sharply increased levels of radiation.
Status of the Nuclear Reactors
A daily tracker of the damage at the two imperiled nuclear plants.
Carlos Barria/Reuters
Tsunami victims in Kesennuma, Japan, dug through debris. The United Nations nuclear chief said Saturday that the country was far from the end of the nuclear crisis.
The developments came after the world’s chief nuclear inspector said that Japan was “still far from the end of the accident” that struck the plant, which continues to spew radiation into the atmosphere and the sea. Yukiya Amano, the director general of the International Atomic Energy Agency, acknowledged that the authorities were still unsure about whether the reactor cores and spent fuel were covered with the water needed to cool them and end the crisis.
Mr. Amano, taking care to say that he was not criticizing Japan’s response under extraordinary circumstances, said, “More efforts should be done to put an end to the accident.”
More than two weeks after a devastating earthquake and tsunami, he cautioned that the nuclear emergency could still go on for weeks, if not months, given the enormous damage to the plant.
His concerns were underscored on Sunday when officials in Japan announced higher levels of radiation in pools of water at the facility’s stricken reactors.
The Nuclear and Industrial Safety Agency said that water seeping out of the crippled No. 2 reactor building into the adjacent turbine building contained levels of radioactive iodine 134 that were about 10 million times the level normally found in water used inside nuclear power plants.
The higher levels may suggest a leak from the reactor’s fuel rods — from either the suppression chamber under the rods or various piping — or even a breach in the pressure vessel that houses the rods, the Japanese nuclear regulator said.
Tetsuo Iguchi, a professor in the department of quantum engineering at Nagoya University, said that at that level of radiation, workers would be able to remain on site for only about 15 minutes before health considerations required them to leave, further complicating work.
“First, Tokyo Electric has to figure out where the leak is coming from,” he said, “then they’ve got to isolate the water somehow. It’s a difficult task.”
Tests also found increased levels of radioactive cesium, a substance with a longer half-life, the Japanese safety agency said.
“Because these substances originate from nuclear fission, there is a high possibility they originate from the reactor,” said Hidehiko Nishiyama, the agency’s deputy director-general, at a news conference. He said that it was likely that radiation was leaking from the pipes or the suppression chamber, and not directly from the pressure vessel, because water levels and pressure in the vessel were relatively stable.
Mr. Nishiyama also said that radioactive iodine in seawater just outside the plant had risen to 1,850 times the usual level on Sunday, up from 1,250 on Saturday.
“Radiation levels are increasing and measures need to be taken,” he said, but added that he did not think there was need to worry about high levels of radiation immediately escaping the plant.
Yukio Edano, the chief cabinet secretary, said he did not think the pressure vessel, which cases the fuel rods, was broken at the No. 2 reactor. He said pressure levels inside the reactor remained higher than atmospheric pressure, suggesting that there was no breach.
“I don’t think the container is breached, but there is a possibility the water is coming from somewhere inside the reactor,” he said. “We want to find out as quickly as possible where the highly radioactive water is leaking from, and take measures to deal with it,” Mr. Edano said on a live interview on the public broadcaster, NHK, early Sunday.
Naoto Sekimura, a professor of engineering at the University of Tokyo, told NHK on Sunday that information suggested that the No. 2 unit at Fukushima was leaking significantly more radiation that the No. 1 unit or the No. 3 unit.
“The No. 2 unit’s suppression pool, which connects to the containment building, is damaged, so its ability to contain radiation has been compromised,” Mr. Sekimura said. “They’ve got to find the source of the leak.”
Separately, the I.A.E.A., citing data from the Japanese authorities, reported that two of three workers who were exposed to radioactive water on Saturday suffered “significant skin contamination over their legs.”
“The Japanese authorities have stated that during medical examinations carried out at the National Institute of Radiological Sciences in the Chiba Prefecture, the level of local exposure to the workers’ legs was estimated to be between 2 and 6 sieverts,” the I.A.E.A. said on its Web site.
“While the patients did not require medical treatment, doctors decided to keep them in hospital and monitor their progress over coming days.”
The elevated levels of radiation at and around the Fukushima plant will require careful monitoring of seafood in Japan, said Kimberlee J. Kearfott, a professor of nuclear engineering and radiological sciences at the University of Michigan.
“It is extremely important that seafood be carefully monitored,” she said in an e-mail. “This is because many of the radionuclides are concentrated in the environment,” she added. “For example, iodines are concentrated in kelp (a Japanese food, seaweed) and shrimp.
“Iodines, cesium and strontium are concentrated in other types of seafood,” she continued. “Fish can act like tea or coffee presses. When you push down the plungers, the grounds all end up on one side. In this case, that is the fish.”
She said an example of this phenomenon occurred after the Chernobyl disaster, when specific radionuclides were concentrated far away in Norwegian lichens. Reindeer ate the lichens, concentrating it again, a danger to the native peoples whose diet includes a large amount of reindeer meat.
William J. Broad reported from New York, and David Jolly from Tokyo. Reporting was contributed by David E. Sanger from Palo Alto, Calif., Hiroko Tabuchi and Chika Ohshima from Tokyo, and Kevin Drew from Hong Kong.
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Higher Radiation Levels Found at Japanese Reactor
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