Mirza Jatt
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corrected...post removed.
Japanese nuclear disaster
- Thread starter Cityboy
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corrected...post removed.
hembo
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Nuclear missteps, safety concerns
Sunday, March 13, 2011
Japan's dependence on nuclear energy soared after 1973 in response to skyrocketing oil prices that year. In 2002, the country mapped a nuclear future that sought to decrease its greenhouse gas emissions by further increasing its reliance on nuclear power. Current plans call for 50 percent of the country's electricity to come from nuclear plants by 2017.
But mishaps and scandals have rocked Japan's nuclear industry:
l In 1999, a burst of radiation at a uranium fuel processing plant 75 miles north of Tokyo killed two workers. In response, the government tightened regulation of the nuclear industry.
l In 2002, Tepco, the company operating the crippled Fukushima Daiichi plant, was rocked by a scandal over falsification of safety data. The company shut down all 17 of its reactors for inspection at a reported cost of $1.9 billion.
l In 2007, a government-ordered review unveiled possible - and previously unreported - radiation leakages at two power plants in 1978 and 1999.
l In July 2007, the Kashiwazaki-Kariwa nuclear plant was shut down for 21 months after a 6.8 magnitude earthquake to strengthen the facility.
- Compiled by Brian Vastag
Sources: World Nuclear Association; International Atomic Energy Agency; Tepco; and Japan's Nuclear and Industrial Safety Agency.
Sunday, March 13, 2011
Japan's dependence on nuclear energy soared after 1973 in response to skyrocketing oil prices that year. In 2002, the country mapped a nuclear future that sought to decrease its greenhouse gas emissions by further increasing its reliance on nuclear power. Current plans call for 50 percent of the country's electricity to come from nuclear plants by 2017.
But mishaps and scandals have rocked Japan's nuclear industry:
l In 1999, a burst of radiation at a uranium fuel processing plant 75 miles north of Tokyo killed two workers. In response, the government tightened regulation of the nuclear industry.
l In 2002, Tepco, the company operating the crippled Fukushima Daiichi plant, was rocked by a scandal over falsification of safety data. The company shut down all 17 of its reactors for inspection at a reported cost of $1.9 billion.
l In 2007, a government-ordered review unveiled possible - and previously unreported - radiation leakages at two power plants in 1978 and 1999.
l In July 2007, the Kashiwazaki-Kariwa nuclear plant was shut down for 21 months after a 6.8 magnitude earthquake to strengthen the facility.
- Compiled by Brian Vastag
Sources: World Nuclear Association; International Atomic Energy Agency; Tepco; and Japan's Nuclear and Industrial Safety Agency.
India is in unique situation with manpower and resource to help and india PM offered that very early on. Some indian member even suggested to dispatch ships. Those are all good ideas and india follow PM words with deeds.
hembo
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Backgrounder: Major nuclear accidents around the world
English.news.cn 2011-03-13 15:46:54
BEIJING, March 13 (Xinhua) -- The Fukushima No.1 nuclear power plant in northeast Japan started to leak radioactive material after an hydrogen explosion, which was caused by a devastating earthquake and ensuring tsunamis, occurred Saturday afternoon.
The following are major nuclear accidents around the world since the former Soviet Union set up the world's first nuclear power plant in 1954:
On Oct. 10, 1957, a fire broke out at the Windscale nuclear reactor (later renamed Sellafield) in northwest England, destroying the core and releasing a cloud of radioactive material. The sale of milk and other produces from nearby farms were banned for a month. Scores of people later developed cancer and died because of exposure to radiation.
On March 28, 1979, a partial core meltdown occurred at Three Mile Island in the United States due to its cooling system failure, in the most severe nuclear leak accident in the country which forced the evacuation of at least 150,000 local residents.
On April 26, 1986, the No.4 reactor at the Chernobyl nuclear plant in the former Soviet Union exploded, causing the worst nuclear disaster in history. The explosion killed 30 people on the spot, released more than eight tons of highly radioactive material, contaminated 60,000 square km of land, and caused more than 3.2 million people to be affected by radiation.
On April 6, 1993, a tank containing radioactive liquid exploded at the Tomsk-7 Reprocessing Complex in the Siberian region of Russia. A total of 10 square km of land was contaminated by radioactive material and a number of nearby villages were evacuated.
On Sept. 30, 1999, a nuclear accident occurred at a nuclear fuel plant at Tokai village, Ibaraki prefecture, Japan, killing two workers, exposing dozens of people to radiation and forcing the evacuation of local residents.
On Aug. 9, 2004, four workers were killed and seven others injured by a steam leak at the No.3 reactor at Kansai Electric's Mihama power plant, 350 km west of Tokyo, Japan.
Editor: Wang Yan
English.news.cn 2011-03-13 15:46:54
BEIJING, March 13 (Xinhua) -- The Fukushima No.1 nuclear power plant in northeast Japan started to leak radioactive material after an hydrogen explosion, which was caused by a devastating earthquake and ensuring tsunamis, occurred Saturday afternoon.
The following are major nuclear accidents around the world since the former Soviet Union set up the world's first nuclear power plant in 1954:
On Oct. 10, 1957, a fire broke out at the Windscale nuclear reactor (later renamed Sellafield) in northwest England, destroying the core and releasing a cloud of radioactive material. The sale of milk and other produces from nearby farms were banned for a month. Scores of people later developed cancer and died because of exposure to radiation.
On March 28, 1979, a partial core meltdown occurred at Three Mile Island in the United States due to its cooling system failure, in the most severe nuclear leak accident in the country which forced the evacuation of at least 150,000 local residents.
On April 26, 1986, the No.4 reactor at the Chernobyl nuclear plant in the former Soviet Union exploded, causing the worst nuclear disaster in history. The explosion killed 30 people on the spot, released more than eight tons of highly radioactive material, contaminated 60,000 square km of land, and caused more than 3.2 million people to be affected by radiation.
On April 6, 1993, a tank containing radioactive liquid exploded at the Tomsk-7 Reprocessing Complex in the Siberian region of Russia. A total of 10 square km of land was contaminated by radioactive material and a number of nearby villages were evacuated.
On Sept. 30, 1999, a nuclear accident occurred at a nuclear fuel plant at Tokai village, Ibaraki prefecture, Japan, killing two workers, exposing dozens of people to radiation and forcing the evacuation of local residents.
On Aug. 9, 2004, four workers were killed and seven others injured by a steam leak at the No.3 reactor at Kansai Electric's Mihama power plant, 350 km west of Tokyo, Japan.
Editor: Wang Yan
hembo
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Oh ok, I now get you intension of the initial post. Not letting go off cheap sarcasm even at the time of other human being's suffering, are we? Bravo!!
hembo
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Potential health problems from radiation exposure
The extent of the risk from a nuclear power plant ultimately depends on how much and what kind of radioactive material is released, where it travels and how many people are exposed for how long.
"Anything having to do with health effects has to do with the amount of exposure the population receives, and that's just an unknown" . "That's determined by many factors, including which way the wind is blowing."
Radiation from nuclear power plants poses a host of health risks, ranging from severe toxic effects in workers exposed to high doses to long-term increased rates of many cancers, experts said.
Most of what is known about the risks of radiation comes from studying survivors of the atomic bombings of Hiroshima and Nagasaki during World War II, the 1986 Chernobyl nuclear disaster in Ukraine and radiation exposures for medical purposes.
In Chernobyl, about 30 firefighters who were exposed to very high doses of radiation while trying to douse the blaze at the plant died within a month.
"They had huge exposures," Boice said. "These were the kind of doses that just knocked out the blood system, the gastrointestinal system."
One worker at the Daiichi plant had died from injuries after becoming trapped in the exhaust stack of the plant, according to the World Nuclear Association. At least four other workers were reportedly injured in the explosion and had been hospitalized.
Beyond the deaths of firefighters in Chernobyl, the most well-documented health effect was an increase in thyroid cancer, primarily among children, due to exposure to iodine-131. An estimated 6,000 to 7,000 excess cases of thyroid cancer have occurred because of Chernobyl, mostly among people who were children at the time.
"At Chernobyl, the biggest problem was it got on the grass and the cows ate it and the milk from the cows was given to the kids," said Fred Mettler, a radiation expert at the University of New Mexico.
Japanese officials announced plans to distribute potassium iodide pills, which block radioactive iodine from accumulating in the thyroid glands, causing thyroid cancer, to people living around the Fukushima Daiichi facility and another damaged plant about seven miles away.
Of the radioactive elements released in a nuclear plant leak, radioactive iodine has a relatively short "half-life" of eight days, which means that it essentially disappears within about 80 days, Mettler said. In comparison, another radioactive substance released by nuclear power plants, cesium-137, has a half-life of about 30 years, meaning it poses a much greater risk because it gets into the food chain.
In the Hiroshima and Nagasaki atomic bombings, which provide some of the best data about the risks of radiation, about 80,000 people died from the blasts and exposure to very high doses of radiation. Studies of the survivors found that rates of a variety of cancers, including leukemia and cancer of the breast, lung and colon, remained elevated for decades.
"The Japanese have been studying radiation since they dropped the bomb over there," Mettler said. "They have been following the atomic bomb survivors for 60 years. They are the world experts on radiation effects. So nothing is lost on them."
Excess cases of leukemia begin to show up within two years of exposure and peak within five to 10 years; other cancers do not start to appear in excess for at least a decade, and their risk can remain elevated for decades. But even in Hiroshima and Nagasaki, only about 9,000 survivors have died from cancer. That's about 500 more cases than would have been normally expected, Mettler said.
Studies have also found adverse psychological effects from nuclear accidents, such as the Chernobyl fire and the 1979 Three Mile Island meltdown in Pennsylvania. For example, there was an increase in suicides in Estonia and among cleanup workers after Chernobyl. Abortions also increased in some places.
"It turns out there wasn't increases in birth defects or malformations in the surrounding populations, but there was an increase in elective abortions because people were so concerned," Boice said.
The extent of the risk from a nuclear power plant ultimately depends on how much and what kind of radioactive material is released, where it travels and how many people are exposed for how long.
"Anything having to do with health effects has to do with the amount of exposure the population receives, and that's just an unknown" . "That's determined by many factors, including which way the wind is blowing."
Radiation from nuclear power plants poses a host of health risks, ranging from severe toxic effects in workers exposed to high doses to long-term increased rates of many cancers, experts said.
Most of what is known about the risks of radiation comes from studying survivors of the atomic bombings of Hiroshima and Nagasaki during World War II, the 1986 Chernobyl nuclear disaster in Ukraine and radiation exposures for medical purposes.
In Chernobyl, about 30 firefighters who were exposed to very high doses of radiation while trying to douse the blaze at the plant died within a month.
"They had huge exposures," Boice said. "These were the kind of doses that just knocked out the blood system, the gastrointestinal system."
One worker at the Daiichi plant had died from injuries after becoming trapped in the exhaust stack of the plant, according to the World Nuclear Association. At least four other workers were reportedly injured in the explosion and had been hospitalized.
Beyond the deaths of firefighters in Chernobyl, the most well-documented health effect was an increase in thyroid cancer, primarily among children, due to exposure to iodine-131. An estimated 6,000 to 7,000 excess cases of thyroid cancer have occurred because of Chernobyl, mostly among people who were children at the time.
"At Chernobyl, the biggest problem was it got on the grass and the cows ate it and the milk from the cows was given to the kids," said Fred Mettler, a radiation expert at the University of New Mexico.
Japanese officials announced plans to distribute potassium iodide pills, which block radioactive iodine from accumulating in the thyroid glands, causing thyroid cancer, to people living around the Fukushima Daiichi facility and another damaged plant about seven miles away.
Of the radioactive elements released in a nuclear plant leak, radioactive iodine has a relatively short "half-life" of eight days, which means that it essentially disappears within about 80 days, Mettler said. In comparison, another radioactive substance released by nuclear power plants, cesium-137, has a half-life of about 30 years, meaning it poses a much greater risk because it gets into the food chain.
In the Hiroshima and Nagasaki atomic bombings, which provide some of the best data about the risks of radiation, about 80,000 people died from the blasts and exposure to very high doses of radiation. Studies of the survivors found that rates of a variety of cancers, including leukemia and cancer of the breast, lung and colon, remained elevated for decades.
"The Japanese have been studying radiation since they dropped the bomb over there," Mettler said. "They have been following the atomic bomb survivors for 60 years. They are the world experts on radiation effects. So nothing is lost on them."
Excess cases of leukemia begin to show up within two years of exposure and peak within five to 10 years; other cancers do not start to appear in excess for at least a decade, and their risk can remain elevated for decades. But even in Hiroshima and Nagasaki, only about 9,000 survivors have died from cancer. That's about 500 more cases than would have been normally expected, Mettler said.
Studies have also found adverse psychological effects from nuclear accidents, such as the Chernobyl fire and the 1979 Three Mile Island meltdown in Pennsylvania. For example, there was an increase in suicides in Estonia and among cleanup workers after Chernobyl. Abortions also increased in some places.
"It turns out there wasn't increases in birth defects or malformations in the surrounding populations, but there was an increase in elective abortions because people were so concerned," Boice said.
hembo
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A very good explanation of events at Fukushima Daiichi Unit 1 and prospects in case of further meltdown:
In Japan plant, frantic efforts to avoid meltdown
Posted: Sunday, March 13, 2011 1:16 am | Updated: 1:21 am, Sun Mar 13, 2011.
TOKYO (AP) — Inside the troubled nuclear power plant, officials knew the risks were high when they decided to vent radioactive steam from a severely overheated reactor vessel. They knew a hydrogen explosion could occur, and it did. The decision still trumped the worst-case alternative — total nuclear meltdown.
At least for the time being.
The chain of events started Friday when a magnitude-8.9 earthquake and tsunami severed electricity to the Fukushima Dai-ichi nuclear complex 170 miles (270 kilometers) northeast of Tokyo, crippling its cooling system. Then, backup power did not kick in properly at one of its units.
From there, conditions steadily worsened, although government and nuclear officials initially said things were improving. Hours after the explosion, they contended that radiation leaks were reduced and that circumstances had gotten better at the 460-megawatt Unit 1. But crisis after crisis continued to develop or be revealed.
Without power, and without plant pipes and pumps that were destroyed in the explosion of the most-troubled reactor’s containment building, authorities resorted to drawing seawater in an attempt to cool off the overheated uranium fuel rods.
Robert Alvarez, senior scholar at the Institute for Policy Studies and former senior policy adviser to the U.S. secretary of energy, said in a briefing for reporters that the seawater was a desperate measure.
“It’s a Hail Mary pass,” he said.
He said that the success of using seawater and boron to cool the reactor will depend on the volume and rate of their distribution. He said the dousing would need to continue nonstop for days.
Another key, he said, was the restoration of electrical power, so that normal cooling systems can be restored.
Officials placed Dai-ichi Unit 1, and four other reactors, under states of emergency Friday because operators had lost the ability to cool the reactors using usual procedures.
An additional reactor was added to the list early Sunday, for a total of six — three at the Dai-ichi complex and three at another nearby complex. Local evacuations have been ordered at each location. Japan has a total of 55 reactors spread across 17 complexes nationwide.
Officials began venting radioactive steam at Fukushima Dai-ichi’s Unit 1 to relieve pressure inside the reactor vessel, which houses the overheated uranium fuel.
Concerns escalated dramatically Saturday when that unit’s containment building exploded.
It turned out that officials were aware that the steam contained hydrogen, acknowledged Shinji Kinjo, spokesman for the government Nuclear and Industrial Safety Agency. More importantly, they also were aware they were risking an explosion by deciding to vent the steam.
The significance of the hydrogen began to come clear late Saturday:
—Officials decided to reduce rising pressure inside the reactor vessel, so they vented some of the steam buildup. They needed to do that to prevent the entire structure from exploding, and thus starting down the road to a meltdown.
—At the same time, in order to keep the reactor fuel cool, and also prevent a meltdown, operators needed to keep circulating more and more cool water on the fuel rods.
—Temperature in the reactor vessel apparently kept rising, heating the zirconium cladding that makes up the fuel rod casings. Once the zirconium reached 2,200 degrees Fahrenheit (1,200 Celsius), it reacted with the water, becoming zirconium oxide and hydrogen.
—When the hydrogen-filled steam was vented from the reactor vessel, the hydrogen reacted with oxygen, either in the air or water outside the vessel, and exploded.
A similar “hydrogen bubble” had concerned officials at the 1979 Three Mile Island nuclear disaster in Pennsylvania until it dissipated.
If the temperature inside the Fukushima reactor vessel continued to rise even more — to roughly 4,000 degrees Fahrenheit (2,200 Celsius) — then the uranium fuel pellets would start to melt.
According to experts interviewed by The Associated Press, any melted fuel would eat through the bottom of the reactor vessel. Next, it would eat through the floor of the already-damaged containment building. At that point, the uranium and dangerous byproducts would start escaping into the environment.
At some point in the process, the walls of the reactor vessel — 6 inches (15 centimeters) of stainless steel — would melt into a lava-like pile, slump into any remaining water on the floor, and potentially cause an explosion much bigger than the one caused by the hydrogen. Such an explosion would enhance the spread of radioactive contaminants.
If the reactor core became exposed to the external environment, officials would likely began pouring cement and sand over the entire facility, as was done at the 1986 Chernobyl nuclear accident in the Ukraine, Peter Bradford, a former commissioner of the U.S. Nuclear Regulatory Commission, said in a briefing for reporters.
At that point, Bradford added, “many first responders would die.
In Japan plant, frantic efforts to avoid meltdown
Posted: Sunday, March 13, 2011 1:16 am | Updated: 1:21 am, Sun Mar 13, 2011.
TOKYO (AP) — Inside the troubled nuclear power plant, officials knew the risks were high when they decided to vent radioactive steam from a severely overheated reactor vessel. They knew a hydrogen explosion could occur, and it did. The decision still trumped the worst-case alternative — total nuclear meltdown.
At least for the time being.
The chain of events started Friday when a magnitude-8.9 earthquake and tsunami severed electricity to the Fukushima Dai-ichi nuclear complex 170 miles (270 kilometers) northeast of Tokyo, crippling its cooling system. Then, backup power did not kick in properly at one of its units.
From there, conditions steadily worsened, although government and nuclear officials initially said things were improving. Hours after the explosion, they contended that radiation leaks were reduced and that circumstances had gotten better at the 460-megawatt Unit 1. But crisis after crisis continued to develop or be revealed.
Without power, and without plant pipes and pumps that were destroyed in the explosion of the most-troubled reactor’s containment building, authorities resorted to drawing seawater in an attempt to cool off the overheated uranium fuel rods.
Robert Alvarez, senior scholar at the Institute for Policy Studies and former senior policy adviser to the U.S. secretary of energy, said in a briefing for reporters that the seawater was a desperate measure.
“It’s a Hail Mary pass,” he said.
He said that the success of using seawater and boron to cool the reactor will depend on the volume and rate of their distribution. He said the dousing would need to continue nonstop for days.
Another key, he said, was the restoration of electrical power, so that normal cooling systems can be restored.
Officials placed Dai-ichi Unit 1, and four other reactors, under states of emergency Friday because operators had lost the ability to cool the reactors using usual procedures.
An additional reactor was added to the list early Sunday, for a total of six — three at the Dai-ichi complex and three at another nearby complex. Local evacuations have been ordered at each location. Japan has a total of 55 reactors spread across 17 complexes nationwide.
Officials began venting radioactive steam at Fukushima Dai-ichi’s Unit 1 to relieve pressure inside the reactor vessel, which houses the overheated uranium fuel.
Concerns escalated dramatically Saturday when that unit’s containment building exploded.
It turned out that officials were aware that the steam contained hydrogen, acknowledged Shinji Kinjo, spokesman for the government Nuclear and Industrial Safety Agency. More importantly, they also were aware they were risking an explosion by deciding to vent the steam.
The significance of the hydrogen began to come clear late Saturday:
—Officials decided to reduce rising pressure inside the reactor vessel, so they vented some of the steam buildup. They needed to do that to prevent the entire structure from exploding, and thus starting down the road to a meltdown.
—At the same time, in order to keep the reactor fuel cool, and also prevent a meltdown, operators needed to keep circulating more and more cool water on the fuel rods.
—Temperature in the reactor vessel apparently kept rising, heating the zirconium cladding that makes up the fuel rod casings. Once the zirconium reached 2,200 degrees Fahrenheit (1,200 Celsius), it reacted with the water, becoming zirconium oxide and hydrogen.
—When the hydrogen-filled steam was vented from the reactor vessel, the hydrogen reacted with oxygen, either in the air or water outside the vessel, and exploded.
A similar “hydrogen bubble” had concerned officials at the 1979 Three Mile Island nuclear disaster in Pennsylvania until it dissipated.
If the temperature inside the Fukushima reactor vessel continued to rise even more — to roughly 4,000 degrees Fahrenheit (2,200 Celsius) — then the uranium fuel pellets would start to melt.
According to experts interviewed by The Associated Press, any melted fuel would eat through the bottom of the reactor vessel. Next, it would eat through the floor of the already-damaged containment building. At that point, the uranium and dangerous byproducts would start escaping into the environment.
At some point in the process, the walls of the reactor vessel — 6 inches (15 centimeters) of stainless steel — would melt into a lava-like pile, slump into any remaining water on the floor, and potentially cause an explosion much bigger than the one caused by the hydrogen. Such an explosion would enhance the spread of radioactive contaminants.
If the reactor core became exposed to the external environment, officials would likely began pouring cement and sand over the entire facility, as was done at the 1986 Chernobyl nuclear accident in the Ukraine, Peter Bradford, a former commissioner of the U.S. Nuclear Regulatory Commission, said in a briefing for reporters.
At that point, Bradford added, “many first responders would die.
Capt.Popeye
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Yes, and about 120,000 people need to be evacuated. Its well under way and on-going.
hembo
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Partial nuclear meltdown "no disaster", expert says
Sun Mar 13, 2011 8:37am EDT
* Partial fuel meltdown is "not a disaster"
* Complete meltdown unlikely - industry expert
VIENNA, March 13 (Reuters) - Any partial meltdown of nuclear fuel in a quake-hit power plant in Japan "is not a disaster" and a complete meltdown is unlikely, a German industry expert said on Sunday.
Robert Engel, a structural analyst and senior engineer at Switzerland's Leibstadt nuclear power plant,said he believed Japanese authorities would be able to manage the situation at the damaged Fukushima facility north of Tokyo.
Engel was an external member of a team sent by the International Atomic Energy Agency (IAEA) to Japan after a 2007 earthquake that hit the Kashiwazaki-Kariwa plant, until then the largest to affect a nuclear complex.
"I think nobody can say at this time whether there is a small melting of any fuel elements or something like that. You have to inspect it afterwards," he told Reuters by phone.
But a partial meltdown "is not a disaster" and a complete meltdown is not likely, he said, suggesting he believed Japanese authorities were succeeding in cooling down the reactors even though the systems for doing this failed after the quake hit.
"I only see they are trying to cool the reactor, that is the main task, and they are trying to get cooling water from the sea," Engel said, stressing he did not have first-hand information about events at the Fukushima facility.
Normally, he said, the water level inside a reactor core is about 3 to 4 metres above the fuel. If the rods are not covered by water for a longer time then a core melting is possible.
"I think they will be able to manage it ... When the (reactor) containment is intact only a small amount of radioactivity can go out, like in Three Mile Island," he said referring to the 1979 nuclear accident in the United States.
At Three Mile Island, a cooling fault led to a build-up of pressure in the radioactive core and resulted in a relatively small radiation leak.
Japan was working on Sunday to prevent the fuel rods in the plant from overheating after radiation leaked into the air.
The government said a building housing a second reactor was at risk of exploding after a blast on Saturday blew the roof off the facility's No. 1 reactor, where there is believed to have been a partial meltdown of the fuel rods.
Experts say the critical issue is what has happened or is happening with the fuel -- which contains nearly all the radioactivity in the plant -- and whether and to what extent it is damaged.
If there is a fuel meltdown, it would release radioactivity, but Engel said there were barriers before it could escape into the atmosphere -- the fuel rods, reactor vessel and containment. (Reporting by Fredrik Dahl; Editing by Myra MacDonald)
Sun Mar 13, 2011 8:37am EDT
* Partial fuel meltdown is "not a disaster"
* Complete meltdown unlikely - industry expert
VIENNA, March 13 (Reuters) - Any partial meltdown of nuclear fuel in a quake-hit power plant in Japan "is not a disaster" and a complete meltdown is unlikely, a German industry expert said on Sunday.
Robert Engel, a structural analyst and senior engineer at Switzerland's Leibstadt nuclear power plant,said he believed Japanese authorities would be able to manage the situation at the damaged Fukushima facility north of Tokyo.
Engel was an external member of a team sent by the International Atomic Energy Agency (IAEA) to Japan after a 2007 earthquake that hit the Kashiwazaki-Kariwa plant, until then the largest to affect a nuclear complex.
"I think nobody can say at this time whether there is a small melting of any fuel elements or something like that. You have to inspect it afterwards," he told Reuters by phone.
But a partial meltdown "is not a disaster" and a complete meltdown is not likely, he said, suggesting he believed Japanese authorities were succeeding in cooling down the reactors even though the systems for doing this failed after the quake hit.
"I only see they are trying to cool the reactor, that is the main task, and they are trying to get cooling water from the sea," Engel said, stressing he did not have first-hand information about events at the Fukushima facility.
Normally, he said, the water level inside a reactor core is about 3 to 4 metres above the fuel. If the rods are not covered by water for a longer time then a core melting is possible.
"I think they will be able to manage it ... When the (reactor) containment is intact only a small amount of radioactivity can go out, like in Three Mile Island," he said referring to the 1979 nuclear accident in the United States.
At Three Mile Island, a cooling fault led to a build-up of pressure in the radioactive core and resulted in a relatively small radiation leak.
Japan was working on Sunday to prevent the fuel rods in the plant from overheating after radiation leaked into the air.
The government said a building housing a second reactor was at risk of exploding after a blast on Saturday blew the roof off the facility's No. 1 reactor, where there is believed to have been a partial meltdown of the fuel rods.
Experts say the critical issue is what has happened or is happening with the fuel -- which contains nearly all the radioactivity in the plant -- and whether and to what extent it is damaged.
If there is a fuel meltdown, it would release radioactivity, but Engel said there were barriers before it could escape into the atmosphere -- the fuel rods, reactor vessel and containment. (Reporting by Fredrik Dahl; Editing by Myra MacDonald)
Capt.Popeye
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^^^
Prima-facie, there seems to be a little comfort in the item above. But I'd wait a while longer to make any conclusions. In the meantime keeping my fingers crossed and hoping.
Prima-facie, there seems to be a little comfort in the item above. But I'd wait a while longer to make any conclusions. In the meantime keeping my fingers crossed and hoping.
hembo
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Tokyo Electric Power Co. says it can no longer control pressure inside some of the reactors at a second nuclear power plant at its Fukushima facility in northeastern Japan, according to Reuters.
That plant is now the second to be placed on Japan's nuclear safety agency's emergency list today, says Kyodo News. Government officials are ordering TEPCO to release some of the vapor from another power plant, which was put on the list earlier today, according to Kyodo.
That plant is now the second to be placed on Japan's nuclear safety agency's emergency list today, says Kyodo News. Government officials are ordering TEPCO to release some of the vapor from another power plant, which was put on the list earlier today, according to Kyodo.
hembo
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You're right. There are two definite sets of experts who are predicting two different scenarios. However we have to go by the worst case scenario. In case of melting of reactor 3 (with Plutonium fuel), and escape of radioactive material to atmosphere, the fall out can be bad. And Japan may not be the only one to encounter it.
I'm keeping my fingers crossed too.
