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A Time to Rethink Nuclear Power – New York Times

As events unfold in Japan, we are witnessing the extreme dangers of nuclear power plants. Every time there is a serious explosion at a nuclear power plant people within a large radius of the site have to be evacuated for long periods of time, or indefinitely, as was the case with Chernobyl. Nuclear power plants are a far greater danger than any prospect of another world war. The fewer that are built, the safer we will all be.

Nuclear power is an international concern and no government anywhere in the world has the right to take it for granted that accidents will not happen. No government has the right to deny that it has a responsibility outside its national borders.

We should now be asking ourselves a very important question: Are atomic power plants really worth it given the trouble they cause when things get out of control?

Maurice Fitzgerald, Shanbally, Ireland


Continue reading here: A Time to Rethink Nuclear Power – New York Times

Radiation Falls at Japan Atomic Plant; Explosion Still Possible

March 13, 2011, 8:49 AM EDT

By Tsuyoshi Inajima and Yuji Okada

(See EXT2 for more news on the earthquake.)

March 13 (Bloomberg) — Japanese officials battling to prevent a potential meltdown at a nuclear power station said an explosion was possible at a second reactor building after the plant’s cooling system failed.

Water levels temporarily fell at Tokyo Electric Power Co.’s No. 3 reactor at the Fukushima Dai-Ichi plant 135 miles north of Tokyo, raising the possibility of a hydrogen explosion, Chief Cabinet Secretary Yukio Edano said in Tokyo today.

Asia’s largest utility is battling to prevent a meltdown of two reactors at the nuclear power station by flooding them with water and boric acid to eliminate the potential for a catastrophic release of radiation into the atmosphere. The station lost power to keep the reactor core cool after the March 11 earthquake, the largest ever recorded in Japan.

The “likelihood of success should be fairly high,” Dale Klein, a professor of nuclear engineering at the University of Texas at Austin and former chairman of the U.S. Nuclear Regulatory Commission, said of the seawater flooding. “This should have been part of their overall strategy to keep the core covered and cooled.”

Radiation rose yesterday after a hydrogen leak caused a blast that destroyed the walls of the No. 1 reactor. Four workers were injured in the explosion, while no damage was reported to the container holding the reactor’s radioactive core, according to Tokyo Electric.

Radiation levels peaked at 13:52 p.m. local time and have declined since, Tokyo Electric spokesman Naoki Tsunoda said.

Wind Directions

Winds in the area of the Fukushima plant are blowing at less than 18 kilometers (11 miles) per hour generally in an easterly direction, according to a 12 p.m. update from the Japan Meteorological Agency.

The International Atomic Energy Agency, in partnership with the World Meteorological Organization, forecasts that winds will blow any atmospheric radiation northeast over the next three days, according to an IAEA statement.

Tokyo Electric is preparing to vent gas from containment areas at neighboring nuclear power station, Fukushima Dai-Ni, spokesman Akitsuka Kobayashi said yesterday. The station has four reactors.

The IAEA said Japan has informed the Vienna-based agency that casualties have risen among workers at the reactor site. A crane worker was killed at the Fukushima Dai-Ni plant and seven emergency response workers have been injured, including four hurt in yesterday’s explosion, the IAEA said in a statement on its website.

Tokyo Electric will start power outages in parts of the greater Tokyo area from tomorrow, according to a company statement.

Nuclear Meltdown

Inadequate cooling of the reactor core may lead to a meltdown, the most dangerous kind of nuclear power accident because of the threat of radiation releases, according to the Nuclear Regulatory Commission. The 1979 partial meltdown at the Three Mile Island reactor in Pennsylvania failed to breach the containment building, according to the commission.

“Only a small amount of active particles made it outside and were released into the atmosphere, so there were no consequences for the population,” Rafael Arutyunyan, first deputy director of Institute for Safety of Nuclear Energy at the Russian Academy of Sciences, said on Russian television over the weekend in reference to Three Mile Island. “That’s the way we’re heading at the moment” in Fukushima, he said.

‘Station Blackout’

The Fukushima complex lost power after the earthquake when its reactors shut automatically and a backup generator failed, making it difficult to circulate cooling water, Tokyo Electric has said. Without circulation, water within the reactor can boil away, exposing the hot fuel rods and starting a meltdown, Klein said. Three Mile Island operators exposed the core by mistake, the U.S. concluded.

“The difference here is that people understand what’s happening,” Klein said. “They are just having difficulty getting the equipment to work because of the very adverse conditions of both an earthquake and a tsunami.”

The type of accident that involves the loss of both the electrical grid and backup power on site is known as a “station blackout,” said Ken Bergeron, a physicist and former staff member at Sandia National Laboratories, where he worked on nuclear reactor accident simulation.

“It’s considered to be extremely unlikely, but the station blackout has been one of the great concerns for decades,” he told reporters on a conference call. “We are in uncharted territory. We are in the land where probability says we shouldn’t be and we are hoping that all of the barriers to release of radioactivity will not fail.”

Chernobyl Meltdown

There are six reactors at the Dai-Ichi site. The unit being flooded, No. 1, is a General Electric Co. boiling-water reactor model that is capable of generating 439 megawatts of power and began commercial operation in 1971, according to the International Atomic Energy Agency.

If the seawater-flooding attempt fails, engineers may have to pump in sand and cement to entomb the reactor, Peter Bradford, another former member of the Nuclear Regulatory Commission, said on the press conference call.

That ended contamination from the 1986 Chernobyl accident in Ukraine, where the meltdown of a reactor without a containment building killed at least 28 workers, the United Nations Scientific Committee on the Effects of Atomic Radiation said in a 2011 report.

Death Toll

Thousands were evacuated in Japan as workers vented radioactive gas yesterday from the Fukushima plant. The death toll from the quake and the tsunami that followed topped 970, with more than 700 missing, 1,683 injured and 350,000 in emergency shelters. The death toll may reach 10,000, national broadcaster NHK reported, citing local police.

Tokyo Electric took almost two years to restart power generation at the Kashiwazaki Kariwa nuclear plant in the country’s northwest after a 6.8 magnitude temblor on July 16, 2007, caused a fire and radiation leaks at the world’s biggest atomic energy station.

Nuclear energy provides almost 30 percent of Japan’s electricity, with total capacity of about 47,000 megawatts, with plans to increase that to 40 percent by 2017, according to the World Nuclear Association. The nation’s first reactor began operating in 1966 and there are 54 reactors in the country.

–With assistance from Yuriy Humber, Michio Nakayama, Aki Ito and Aaron Sheldrick in Tokyo, Anna Shiryaevskaya in Moscow, Kim Chipman in Washington, Jim Polson in New York and Rachel Layne in Boston. Editors: Amit Prakash, Peter Langan

To contact the reporters on this story: Tsuyoshi Inajima in Tokyo at [email protected]; Yuji Okada in Tokyo at [email protected]

To contact the editor responsible for this story: Amit Prakash at [email protected]

Continue reading here: Radiation Falls at Japan Atomic Plant; Explosion Still Possible

Radiation Exceeds Regulatory Levels at Japan Nuclear Plant

March 12, 2011, 10:58 PM EST

By Tsuyoshi Inajima and Yuji Okada

(See EXT2 for more news on the earthquake.)

March 13 (Bloomberg) — Radiation levels increased near the Fukushima nuclear power plant 135 miles north of Tokyo and cooling systems at a second reactor failed, intensifying concerns about a possible meltdown.

The radiation at the Fukushima Dai-Ichi plant exceeded Japanese limits after an explosion yesterday destroyed the walls of the reactor building and injured four workers following the magnitude-8.9 earthquake on March 11, said Naoyuki Matsumoto, a spokesman for Tokyo Electric Power Co., the operator of the plant. No damage to the building housing the reactor was reported, the company said.

Tokyo Electric is battling to prevent a meltdown of two reactors at the nuclear power station by flooding them with water and boric acid to eliminate the potential for a catastrophic release of radiation. The station lost power needed to keep the reactor core cool after the earthquake two days ago, the largest ever recorded in Japan.

Chief Cabinet Secretary Yukio Edano, Japan’s top government spokesman, said today the radiation is not at a dangerous level.

Winds in the area of the Fukushima plant are blowing at less than 18 kilometers (11 miles) per hour generally in an easterly direction, according to a 12 p.m. update from the Japan Meteorological Agency.

Tokyo Electric began injecting sea water and boric acid to cool its Fukushima Dai-Ichi No. 1 reactor, according to a statement today. The plant’s No. 3 reactor has been vented to release pressurized gas after its cooling system failed, said spokesman Akitsuka Kobayashi.

Success ‘High’

The “likelihood of success should be fairly high,” Dale Klein, a professor of nuclear engineering at the University of Texas at Austin and former chairman of the U.S. Nuclear Regulatory Commission, said of the seawater flooding. “This should have been part of their overall strategy to keep the core covered and cooled.”

Inadequate cooling of the reactor core may lead to a meltdown, the most dangerous kind of nuclear power accident because of the threat of radiation releases, according to the Nuclear Regulatory Commission. The 1979 partial meltdown at the Three Mile Island reactor in Pennsylvania failed to breach the containment building, according to the commission.

“Only a small amount of active particles made it outside and were released into the atmosphere, so there were no consequences for the population,” Rafael Arutyunyan, first deputy director of Institute for Safety of Nuclear Energy at the Russian Academy of Sciences, said on Russian television over the weekend in reference to Three Mile Island. “That’s the way we’re heading at the moment” in Fukushima, he said.

Lost Power

The Fukushima complex lost power after the earthquake when its reactors shut automatically and a backup generator failed, making it difficult to circulate cooling water, Tokyo Electric has said. Without circulation, water within the reactor can boil away, exposing the hot fuel rods and starting a meltdown, Klein said. Three Mile Island operators exposed the core by mistake, the U.S. concluded.

“The difference here is that people understand what’s happening,” Klein said. “They are just having difficulty getting the equipment to work because of the very adverse conditions of both an earthquake and a tsunami.”

The type of accident that involves the loss of both the electrical grid and backup power on site is known as a “station blackout,” said Ken Bergeron, a physicist and former staff member at Sandia National Laboratories, where he worked on nuclear reactor accident simulation.

‘Station Blackout’

“It’s considered to be extremely unlikely, but the station blackout has been one of the great concerns for decades,” he told reporters on a conference call. “We are in uncharted territory. We are in the land where probability says we shouldn’t be and we are hoping that all of the barriers to release of radioactivity will not fail.”

Radioactive cesium, a product of atomic fission, was detected near the site yesterday, indicating a meltdown may have begun, said Yuji Kakizaki, a spokesman for the Nuclear and Industrial Safety Agency.

“If the fuel rods are melting and this continues, a reactor meltdown is possible,” Kakizaki said.

There are six reactors at the Dai-Ichi site. The unit being flooded, No. 1, is a General Electric Co. boiling-water reactor model that is capable of generating 439 megawatts of power and began commercial operation in 1971, according to the International Atomic Energy Agency.

If the seawater-flooding attempt fails, engineers may have to pump in sand and cement to entomb the reactor, Peter Bradford, another former member of the Nuclear Regulatory Commission, said on the press conference call.

Chernobyl Meltdown

That ended contamination from the 1986 Chernobyl accident in Ukraine, where the meltdown of a reactor without a containment building killed at least 28 workers, the United Nations Scientific Committee on the Effects of Atomic Radiation said in a 2011 report.

Thousands were evacuated in Japan as workers vented radioactive gas yesterday from the plant 220 kilometers (140 miles) north of Tokyo. The death toll from the quake and a tsunami that swept over the northern coastline after the quake topped 600 and an estimated 4,000 were stranded in evacuation centers.

Rain or Snow

Temperatures may fall bringing rain or snow to earthquake stricken northern Japan after tomorrow, with lows dropping to 1 degree Celsius (34 degrees Farenheit), according to Japan Meteorological Agency forecasts. Lows may fall below freezing later in the week, the agency said.

The reactor at the Fukushima Dai-Ichi plant may remain shut for a year, Seth Grae, chief executive officer of Lightbridge Corp., a nuclear energy consulting company whose staff previously inspected the plant, said in an interview with Pimm Fox on Bloomberg Television’s “Taking Stock” on March 11.

“If they do lose several of those plants for a few months it could have a significant effect on Japan’s economy,” he said. “A trickle down could hit factories, slowing down Japan’s production.”

Japanese Reactors

Tokyo Electric took almost two years to restart power generation at the Kashiwazaki Kariwa nuclear plant in the country’s northwest after a 6.8 magnitude temblor on July 16, 2007, caused a fire and radiation leaks at the world’s biggest atomic energy station.

Nuclear energy provides almost 30 percent of Japan’s electricity, with total capacity of about 47,000 megawatts, with plans to increase that to 40 percent by 2017, according to the World Nuclear Association. The nation’s first reactor began operating in 1966 and there are 54 reactors in the country. A nuclear plant usually operates as many as 8 reactors.

A neighboring nuclear power station, Fukushima Dai-Ni, has four reactors. Tokyo Electric has also started preparing to vent gas from containment areas at that plant, Akitsuka Kobayashi, a company spokesman, said yesterday.

“When the pressure starts building up, the emergency procedure is to start venting,” Dave Lochbaum, director of the nuclear safety project at the Union for Concerned Scientists, said in a telephone interview. “They’ve essentially entered a beat-the-clock game. As long as there is no fuel damage, there will be radioactivity, but it will be very low.”

–With assistance from Yuriy Humber, Michio Nakayama and Aki Ito in Tokyo, Anna Shiryaevskaya in Moscow, Kim Chipman in Washington, Jim Polson in New York and Rachel Layne in Boston. Editors: Teo Chian Wei, Aaron Sheldrick.

To contact the reporters on this story: Tsuyoshi Inajima in Tokyo at [email protected]; Yuji Okada in Tokyo at [email protected]

To contact the editor responsible for this story: Amit Prakash at [email protected]

Continue reading here: Radiation Exceeds Regulatory Levels at Japan Nuclear Plant

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Analysis: How bad is the nuclear accident in Japan?

NEW YORK (Reuters) – The Japanese nuclear safety agency rated the damage at a nuclear power plant at Fukushima at a four on a scale of one to seven, which is not quite as bad as the Three Mile Island accident in the United States in 1979, which registered a five. But what does that mean?

The International Atomic Energy Agency — an inter-governmental organization for scientific co-operation in the nuclear field — said it uses the scale to communicate to the public in a consistent way the safety significance of nuclear and radiological events.

The International Nuclear and Radiological Event Scale, or INES, ranges from one to seven with the most serious being a seven referred to as a “major accident”, while a one is an “anomaly”. The scale is designed so the severity of an event is about ten times greater for each increase in level.

The Chernobyl explosion in the Ukraine in 1986, the worst nuclear power accident ever, was rated a seven. That was the only event classified as a major accident in nuclear power history, exploded due to an uncontrolled power surge that damaged the reactor core, releasing a radioactive cloud that blanketed Europe.

The Three Mile Island accident in Pennsylvania was a partial core meltdown in which the metal cladding surrounding the fuel rods started to melt. That metal surrounds the ceramic uranium fuel pellets, which hold most of the radiation and power the reactor.

Nuclear reactors operate at between 550 and 600 degrees F (between 288 and 316 degrees C). The metal on the fuel rods will not melt until temperatures are well above 1000 degrees F. The ceramic uranium pellets themselves won’t melt until about 2000 degrees.

About half the reactor core at Three Mile Island melted before operators restored enough cooling water to stop the meltdown. The core holds the uranium fuel rods, which must be cooled by water to prevent overheating.

So what happened at Fukushima?

The blast at the 40-year-old Daiichi 1 reactor came as plant operator Tokyo Electric Power Co (Tepco) worked to reduce pressure from mildly radioactive steam in the core after the total loss of power needed to keep water circulating to prevent the reactor fuel from overheating.

That blast led to fears of a disastrous meltdown at the plant, which automatically shut after the quake, even though the government has insisted that radiation levels were low.

The cause and exact location of the blast still needs to be established, nuclear experts queried about the incident said.

A couple of examples of fours on the INES scale include a fatal overexposure of workers following an incident at a nuclear facility at Tokaimura, Japan in 1999 and the melting of one channel of fuel in the reactor — though no radiation was released outside the site — at Saint Laurent des Eaux, France in 1980.

(Reporting by Scott DiSavino in New York, Bernie Woodall in Detroit and Fredrik Dahl in Vienna. Editing by Martin Howell)

Continue reading here: Analysis: How bad is the nuclear accident in Japan?