Sources from Fukushima have reported that the workers have managed to stop the water leak from reactor 2, thus putting an end to the flow of the highly radioactive iodine into the ocean. They had been working around the clock, struggling for almost a month to keep the damaged reactors from overheating. Nevertheless, the Japanese officials warned that the fight is still far from over.
Until Wednesday, radioactive liquid was flowing into the ocean from a cracked concrete shaft near the turbine plant's water intake. Workers managed to seal that breach on Wednesday morning, but officials say they still have other important problems to solve.
"Is it completely stopped? We cannot be optimistic, just because we were able to plug this one." said Yukio Edano, chief of the Secretary Cabinet. Hidehiko Nishiyama of Japan's Nuclear and Industrial Safety Agency said the now-contained water "may lead to more leakage somewhere else."
Precautionary measures have been taken to minimize the risk of any additional explosions at other reactors. TEPCO announced that "The possibility of a hydrogen explosion is extremely low, but more hydrogen could eventually develop in the containment vessel." Hydrogen buildup is a symptom of overheating fuel rods and can cause explosions like the blast that blew the roof off reactor 1 and 3. But Tokyo Electric said it did not believe any explosion was imminent.
Since the leak was discovered (on Saturday, April 2nd), concentrations of iodine-131 measured in the water near the reactor have been million times higher than the legal limites. After plugging the leak, they have dropped dramatically (to less than 4 percent of that amount) in 24 hours, according to figures released by Tokyo Electric. The level remained 280,000 times higher than the legal limit, but these concentrations are dropping fast. The levels of cesium-137 remained higher than those of the iodine (about 61,000 times the legal limit), but much lower than initially measured during the leak.
Samples from a monitoring point 20 kilometers South-East of the plant found iodine-131 levels down to 1.5 times legal limit, with no reading for cesium. Experts said that the existing releases should not pose any long-term health risks to humans or sea life, as most radiatioactive particles detected are iodine-131 which loses half of its radiation every eight days.
Nevertheless, the existence of this still significant amount of radioactive water around the facility suggests that there may be other leaks and other problems.
Showing posts with label reactor. Show all posts
Showing posts with label reactor. Show all posts
Thursday, April 7, 2011
Friday, April 1, 2011
Modern Samurai - Fukushima's suicide teams
"The Suicide Team" or "Samurai", as they are being called, make up a group of workers still trying to avoid a nuclear disaster at Fukushima, will be paying the ultimate price.
The Japanese Government is offering high salaries for workers willing to sacrifice themselves for "the good of the nation". And there are many who accept to consciously expose themselves to high radiation levels in order to try and stabilize the nuclear reactors and prevent core meltdown.
The core in reactor 2 is melting
The core in reactor 2 seems to have almost completely melted, warned experts on Tuesday, spreading fear that workers will not be able to save the reactor and avoid radioactive gases leaking into the atmosphere.
Richard Lahey, who was chief of one the safety research teams at General Electric back when the company had installed units in Fukushima, said that in his opinion, the workers still pumping water over these 3 reactors practically have already lost the battle.
Workers at Fukushima paid with 1,000 euros per day
According to The Independent, workers receive amounts between 80,000 and 100,000 yen per day, or the equivalent of about 1,000 euros/day. The amount was disclosed by a former worker who was part of the team at Fukushima.
Employees from Fukushima nuclear plant are being exposed to high levels of radiation in an attempt to control the overheated reactor core. They agree to work in these conditions, although they are conscious that it's a suicide mission.
Heroes of Fukushima: "It is inevitable that some of them will die in the coming weeks"
Workers from the team "Fukushima 50" are trying to cool the nuclear power reactors are repeatedly expose themselves to high radioactive levels.
"My son and his colleagues have discussed and are willing to die if necessary to save the nation" said the mother of a 32 year old worker. "He told me that they have all accepted the idea that they will probably die soon after because of high radiation or long-term due to cancer."
She could not confirm whether her son or other workers already suffered from any diseases caused by radiation, but said it was inevitable that some of them would die in the coming weeks or months.
"They know that it is impossible not to have been exposed to deadly doses of radiation" said the worker's mother.
Japanese Prime Minister, Naoto Kan, said Thursday, while in a conversation with the Japanese Communist Party leader, that the damaged Fukushima nuclear power plant will most probably have to be torn down for good.
The Japanese Government is offering high salaries for workers willing to sacrifice themselves for "the good of the nation". And there are many who accept to consciously expose themselves to high radiation levels in order to try and stabilize the nuclear reactors and prevent core meltdown.
The core in reactor 2 is melting
The core in reactor 2 seems to have almost completely melted, warned experts on Tuesday, spreading fear that workers will not be able to save the reactor and avoid radioactive gases leaking into the atmosphere.
Richard Lahey, who was chief of one the safety research teams at General Electric back when the company had installed units in Fukushima, said that in his opinion, the workers still pumping water over these 3 reactors practically have already lost the battle.
Workers at Fukushima paid with 1,000 euros per day
According to The Independent, workers receive amounts between 80,000 and 100,000 yen per day, or the equivalent of about 1,000 euros/day. The amount was disclosed by a former worker who was part of the team at Fukushima.
Employees from Fukushima nuclear plant are being exposed to high levels of radiation in an attempt to control the overheated reactor core. They agree to work in these conditions, although they are conscious that it's a suicide mission.
Heroes of Fukushima: "It is inevitable that some of them will die in the coming weeks"
Workers from the team "Fukushima 50" are trying to cool the nuclear power reactors are repeatedly expose themselves to high radioactive levels.
"My son and his colleagues have discussed and are willing to die if necessary to save the nation" said the mother of a 32 year old worker. "He told me that they have all accepted the idea that they will probably die soon after because of high radiation or long-term due to cancer."
She could not confirm whether her son or other workers already suffered from any diseases caused by radiation, but said it was inevitable that some of them would die in the coming weeks or months.
"They know that it is impossible not to have been exposed to deadly doses of radiation" said the worker's mother.
Japanese Prime Minister, Naoto Kan, said Thursday, while in a conversation with the Japanese Communist Party leader, that the damaged Fukushima nuclear power plant will most probably have to be torn down for good.
The Fukushima nuclear plant could be buried in concrete
The solution from Chernobyl could eventually be applied at Fukushima.
Two of the largest concrete pumps in the world will be sent next week from the United States to Fukushima. They will be transported on board the world's largest cargo plane - the Antonov 225.
Each pump can pour out 160 cubic meters of concrete per hour. Another two somewhat smaller pumps are already on their way (Vietnam and Germany) towards Tokyo.
At first, the pumps will be used in a final attempt to cool the reactors. However, if the operation fails, the reactors will most probably be covered with concrete.
Two of the largest concrete pumps in the world will be sent next week from the United States to Fukushima. They will be transported on board the world's largest cargo plane - the Antonov 225.
Each pump can pour out 160 cubic meters of concrete per hour. Another two somewhat smaller pumps are already on their way (Vietnam and Germany) towards Tokyo.
At first, the pumps will be used in a final attempt to cool the reactors. However, if the operation fails, the reactors will most probably be covered with concrete.
Saturday, March 26, 2011
High level of radioactive iodine measured in the sea water near Fukushima
A radioactive iodine level 1,250 times higher than normal has been measured in the sea water, a few hundred meters off the coast near the Fukushima nuclear power plant, in North-Eastern Japan, announced on Saturday the Japanese Agency for Nuclear Safety.
The agency said the tests had been conducted by the company that manages power plant, Tokyo Electric Power Company (TEPCO), in the water off the coast of reactor 1.
"If you drank 500 ml of water with this concentration of iodine, you would immediately reach the annual maximum limit that you can absorb. This is a relatively high level." said an agency spokesman.
He added that "the radioactivity released into the sea will dilute due to the tide, which in turn means that the concentration would have to be much higher for marine algae and animals to absorb", he added.
"In addition, the concentration of iodine is reducing itself by half every eight days, so that when people will eat these sea food products, the quantity will most likely be greatly reduced" he said.
Tuesday, the level of iodine 131 was 126 times higher than the legal limit set by the Government in the water tested in the Pacific Ocean at the exact same place, near Fukushima Daiichi plant. Therefore, radioactive iodine concentration increased approximately ten times in just a few days.
Public authorities have announced increased controls imposed on fish and seafood caught along the coast.
This nuclear power plant located 250 km North-East of Tokyo, was severely damaged by the earthquake followed by a tsunami on March 11. Cooling systems at four of the reactors have been shut down since then, resulting in numerous incidents and emissions of radioactive particles.
The agency said the tests had been conducted by the company that manages power plant, Tokyo Electric Power Company (TEPCO), in the water off the coast of reactor 1.
"If you drank 500 ml of water with this concentration of iodine, you would immediately reach the annual maximum limit that you can absorb. This is a relatively high level." said an agency spokesman.
He added that "the radioactivity released into the sea will dilute due to the tide, which in turn means that the concentration would have to be much higher for marine algae and animals to absorb", he added.
"In addition, the concentration of iodine is reducing itself by half every eight days, so that when people will eat these sea food products, the quantity will most likely be greatly reduced" he said.
Tuesday, the level of iodine 131 was 126 times higher than the legal limit set by the Government in the water tested in the Pacific Ocean at the exact same place, near Fukushima Daiichi plant. Therefore, radioactive iodine concentration increased approximately ten times in just a few days.
Public authorities have announced increased controls imposed on fish and seafood caught along the coast.
This nuclear power plant located 250 km North-East of Tokyo, was severely damaged by the earthquake followed by a tsunami on March 11. Cooling systems at four of the reactors have been shut down since then, resulting in numerous incidents and emissions of radioactive particles.
Friday, March 18, 2011
Japan has lifted the serverity level of the Fukushima accident from 4 to 5
11.35 Update: The Japanese Nuclear Agency raised from 4 to 5 the severity level of the accident at Fukushima.
10.10 Update: Japanese engineers take into account burying the nuclear reactor in sand and concrete in order to save Japan from a nuclear catastrophe.
Nevertheless, the potential nuclear disaster at Fukushima has a good chance of being avoided. The technicians have restored the electricity supply necessary for the cooling pumps at reactors 5 and 6. The situation situation still remains critic at the other four reactors, more seriously damaged by explosions and fires.
Meanwhile, the radioactivity level near the nuclear power plant has decreased slightly. A priority remains cooling the first four reactors, where it's believed that part of the nuclear fuel (in the reactor's core) has already melted. Technicians continue their efforts to restore the operation of the cooling pumps, which triggered the this chain of events in the first place. Until now, water has been poured over the reactors from helicopters, which seems to have slowly started to stabilize the situation.
As a precaution, passengers and goods arriving from Japan are being tested for radioactivity in airports. So far they have only detected radiation in certain parcels of goods, but the level is still far below the risk limits.
10.10 Update: Japanese engineers take into account burying the nuclear reactor in sand and concrete in order to save Japan from a nuclear catastrophe.
Nevertheless, the potential nuclear disaster at Fukushima has a good chance of being avoided. The technicians have restored the electricity supply necessary for the cooling pumps at reactors 5 and 6. The situation situation still remains critic at the other four reactors, more seriously damaged by explosions and fires.
Meanwhile, the radioactivity level near the nuclear power plant has decreased slightly. A priority remains cooling the first four reactors, where it's believed that part of the nuclear fuel (in the reactor's core) has already melted. Technicians continue their efforts to restore the operation of the cooling pumps, which triggered the this chain of events in the first place. Until now, water has been poured over the reactors from helicopters, which seems to have slowly started to stabilize the situation.
As a precaution, passengers and goods arriving from Japan are being tested for radioactivity in airports. So far they have only detected radiation in certain parcels of goods, but the level is still far below the risk limits.
Thursday, March 17, 2011
Hope revives: Reactor 2 connected to an external source of electricity
Japanese authorities have informed the International Atomic Energy Agency that engineers were able to finally connect one of the reactors (Reactor 2 of the Fukushima nuclear power plant) to an external source of electricity.
Tepco had been trying to connect the power line yesterday, but radiation risks postponed the work.
The new power line means that they will most likely be able to cool down the core of the reactor before it melts. Tepco already had resorted to cooling reactors 1, 2, and 3 with seawater, including dropping several loads of water from a helicopter, insufficient though to successfully reduce the reactor's core temperature.
Due next for a connection is reactor 3, which suffered a previous explosion of its own and which is fueled by a more hazardous combination of uranium and plutonium oxide.
Tepco had been trying to connect the power line yesterday, but radiation risks postponed the work.
The new power line means that they will most likely be able to cool down the core of the reactor before it melts. Tepco already had resorted to cooling reactors 1, 2, and 3 with seawater, including dropping several loads of water from a helicopter, insufficient though to successfully reduce the reactor's core temperature.
Due next for a connection is reactor 3, which suffered a previous explosion of its own and which is fueled by a more hazardous combination of uranium and plutonium oxide.
Japan: Next 48 hours are crucial at Fukushima
The radiation level at the Fukushima nuclear plant in Japan is "extremely high". The warning was released by the chief of the American Nuclear Regulating Commission. The Institute for Nuclear Safety, France, announced that the next 48 hours will be crucial in Fukushima. Last night the head of the International Atomic Energy Agency admitted that the situation at the nuclear power is "very serious".
U.S. warning is especially important when it comes from the most important agencies inthe nuclear field.
"We are halfway between a disaster and an even greater disaster. During the next hours catastrophic developments could happen and there is a real danger to the health and life of the island's inhabitants" said a European Energy Commissioner.
The IAEA Director stated that the Fukushima Daiichi nuclear power plant situation is very serious. The interior of the three reactors was damaged and currently it is not known exactly what the situation is inside the reactors.
Meanwhile, the Fukushima response teams are struggling to drop the core temperature of the reactors. Two military helicopters have dropped tons of seawater over reactor 3, damaged by an explosion on Monday night. Helicopters have made four drops of about 100 needed, but the radiation level remained unchanged. Yesterday operation failed due to strong winds.
Faced with the threat of a major nuclear accident, most embassies have advised their citizens to depart from the area towards the south, in the Osaka region, or leave Japan altogether. The U.S. Embassy has established a risk zone at 80 km around the plant.
U.S. warning is especially important when it comes from the most important agencies inthe nuclear field.
"We are halfway between a disaster and an even greater disaster. During the next hours catastrophic developments could happen and there is a real danger to the health and life of the island's inhabitants" said a European Energy Commissioner.
The IAEA Director stated that the Fukushima Daiichi nuclear power plant situation is very serious. The interior of the three reactors was damaged and currently it is not known exactly what the situation is inside the reactors.
Meanwhile, the Fukushima response teams are struggling to drop the core temperature of the reactors. Two military helicopters have dropped tons of seawater over reactor 3, damaged by an explosion on Monday night. Helicopters have made four drops of about 100 needed, but the radiation level remained unchanged. Yesterday operation failed due to strong winds.
Faced with the threat of a major nuclear accident, most embassies have advised their citizens to depart from the area towards the south, in the Osaka region, or leave Japan altogether. The U.S. Embassy has established a risk zone at 80 km around the plant.
Wednesday, March 16, 2011
Japan's nuclear crisis - The situation is still deteriorating
The fire at the reactor 4 is "apparently out", they announced on Tuesday several Japanese publications. "The fire which occurred on the fourth floor of the reactor 4 is apparently off, " said agency Jiji.
IAEA stated that there were places whre the radioactivity was up to 400 milisievert per hour. Medical observations show that starting from a level of 100 milisievert/h the cancer risk is increasing dramatically in the human body.
As the situation develops, people are starting to compare the potential of this crisis with the 1986 Chernobyl explosion. The author William Tucker said "This is not going to be a Chernobyl... The Soviets didn't have a containment structure on top of their reactor."
The Fukushima Daiichi nuclear plant does. It has a massive structure of concrete and steel sitting on top of its reactors. But given the fact that the emergency cooling system failed due to the tsunami, the authorities are now trying other ways of containing the situation, like pumping seawater to cool the fuel rods and even using a helicopter to attack the problem directly from above.
The plant's operator, Tokyo Electric Power Company, has tried to keep the population calm, saying that serious radioactive leaks can be averted. But given the company's track record, we can't help but question their candidness.
"The history of Japan's nuclear industry and the government, that is very closely tied with the industry, is less than glorious in regards to public information and full disclosure, and what is going on now is actually an illustration of that," says Arjun Mahkhijani, president of the Institute for Energy and Environmental Research.
In 2002, TEPCO's president and some executives resigned after it was revealed that they have falsified the repair and inspection records. "It was discovered that TEPCO had covered up incidents of cracking in an important piece of equipment with the reactors' vessels of all its reactors, and as a result, they were forced to close down all 17 reactors," says Philip White of the Citizens Nuclear Information Center.
Then, in 2007, after a 6.8-magnitude earthquake, TEPCO told the public the plant had only suffered a minor fire and leak of radioactive water. It was later revealed that the fire had burned for a few hours and hundreds of gallons of radioactive water had leaked into the sea.
For the moment though, the situation at Japan's Fukushima Daiichi nuclear plant has not reached a critical level, but the events are still unfolding.
We'll just have to keep an eye on these developments. So follow the news!
Tuesday, March 15, 2011
Germany closes 7 nuclear reactors
Germany will close all seven nuclear reactors that had gone into operation before 1980, and it is currently unclear whether they will be restarted, writes Reuters.
The announcement was made by German Chancellor Angela Merkel after the several explosions in the last few days in Fukushima at one of the largest nuclear plants in Japan, following a 9-degree earthquake that devastated the country. "Nuclear power stations that have started before 1980 will be stopped during the moratorium" said the German Chancellor on Tuesday.
The announcement was made by German Chancellor Angela Merkel after the several explosions in the last few days in Fukushima at one of the largest nuclear plants in Japan, following a 9-degree earthquake that devastated the country. "Nuclear power stations that have started before 1980 will be stopped during the moratorium" said the German Chancellor on Tuesday.
The Environment Minister Norbert Roettgen said that it is not yet clear whether the plants closed during the moratorium will ever be restarted.
Merkel announced on Monday a three-month provisional mortarium life extension of nuclear plants, while the nuclear accident in Japan has exacerbated the traditional hostility of the German population against atomic energy.
As promised in the campaign of 2009, the Chancellor decided to extend the 12 years average lifetime of the reactors, while environmentalists allied with the Social Democrats have scheduled a decade ago a gradual stop in 2020.
According to the European Nuclear Society, there were 17 active nuclear plants in Germany (as of the end of last year) with an electricity production of 21,500 MW and an annual quantity of electricity delivered of about 150 billion kW.
Radiation exposure threat in Japan
In a nutshell: Nuclear alert and radioactive leakage, smoldering fires at the refinery, thousands of people still trapped under rubble, interrupted communications, and dozens of replicas of the huge earthquake still rock Japan.
The Japanese Government declared a state of emergency following the earthquake off the eastern coast of the country on Friday, 11.March. The first estimates say that over 3,000 people died in the magnitude 9.0 earthquake and the devastating tsunami that followed, but authorities fear that the actual death toll could exceed 10,000. Nevertheless, the search for survivors continues.
After the earthquake, all nuclear reactors in the area automatically shut down, beginning a slow cool-down process. Howerver, the cooling systems in the 40-year old Fukushima nuclear reactors 1 and 3 failed and the coolant began to evaporate from heat building up inside. To reduce pressure, the steam had to be vented, which released the first amount of radiation into the atmosphere. Caesium-137 and Iodine-131 were detected near Reactor 1. The nuclear alert in Japan is currently just one step bellow the maximum alert level established in the Chernobyl accident.
A fire at a fourth reactor followed by an explosion has released even more radiation and the Government is currently telling people within a 20-mile radius to stay indoors.
More and more countries express concern over Japan's nuclear incidents. Radiation is also increasing in Russia, where Russian troops are preparing to evacuate residents of the Kuril Islands and Sakhalin, in the event of a worsening situation.
The Japanese Government declared a state of emergency following the earthquake off the eastern coast of the country on Friday, 11.March. The first estimates say that over 3,000 people died in the magnitude 9.0 earthquake and the devastating tsunami that followed, but authorities fear that the actual death toll could exceed 10,000. Nevertheless, the search for survivors continues.
After the earthquake, all nuclear reactors in the area automatically shut down, beginning a slow cool-down process. Howerver, the cooling systems in the 40-year old Fukushima nuclear reactors 1 and 3 failed and the coolant began to evaporate from heat building up inside. To reduce pressure, the steam had to be vented, which released the first amount of radiation into the atmosphere. Caesium-137 and Iodine-131 were detected near Reactor 1. The nuclear alert in Japan is currently just one step bellow the maximum alert level established in the Chernobyl accident.
A fire at a fourth reactor followed by an explosion has released even more radiation and the Government is currently telling people within a 20-mile radius to stay indoors.
More and more countries express concern over Japan's nuclear incidents. Radiation is also increasing in Russia, where Russian troops are preparing to evacuate residents of the Kuril Islands and Sakhalin, in the event of a worsening situation.
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