Entries in Nuclear Reactors (5)


Japan Restarts Nuclear Reactors

STR/AFP/Getty Images(NEW YORK) -- Japanese Prime Minister Yoshihiko Noda ordered the restart of two idle nuclear reactors Saturday amid widespread public opposition, more than a year after a powerful earthquake and tsunami triggered three nuclear meltdowns at the Fukushima Dai-ichi Power Plant, and halted all 50 reactors in Japan.

The decision to reactivate the Ohi reactors in western Japan marks the first time the government has turned nuclear power back on since the Fukushima accident, the worst nuclear disaster since Chernobyl. Japan was rocked by a series of powerful earthquakes and a tsunami in March 2011.

Operator Kansai Electric Power or KEPCO said it would take several weeks to restart its reactors. They could be fully operational by late July.

"We will increase our efforts to restore the public's trust over nuclear safety regulation and atomic energy administration," Noda said, following a meeting with ministers.

Saturday's decision comes as the government scrambles to shore up its energy supply, to avert power shortages during the summer months, when usage is at its peak.

KEPCO provides power to Kansai, the area around Osaka, Japan's third-largest city. Without the Ohi reactors, the utility has said the region would see a 15 percent electricity shortfall in July and August.

Japan relied on nuclear power for a third of its energy prior to the Fukushima disaster, but all 50 reactors have been taken offline since, for maintenance and safety checks.

Noda, who favors reducing Japan's reliance on nuclear power overtime, has aggressively pushed to turn existing reactors back on, saying the country's economy depended on it. But the Japanese public remains largely opposed to the idea.

Recent polls show a majority of the public opposes the restart of the Ohi reactors, and think Japan should reduce its reliance on nuclear power.

In a sign of how polarizing the issue has become, crowds of demonstrators protested outside the Prime Minister's residence in the rain, as Noda met with ministers.

In Koriyama city, where many of the 80,000 evacuees displaced by the nuclear disaster now live, residents said the government was acting too quickly, just 15 months after the Fukushima accident.

"[The politicians] don't care because it doesn't affect them," one man told broadcaster NHK. "They act as if they're taking responsibility but they're not. Nothing has been resolved."

The focus will now shift to the remaining 48 reactors, and how quickly the government moves to resume operations.

Officials will likely hold off on any decision until a new, more independent nuclear regulatory agency is created, to replace the old one.

The Japanese parliament is expected to pass a bill calling for that change, as early as next week.

Copyright 2012 ABC News Radio


US Report: Japan's Nuclear Plant Is Far From Stable

ABC News(TOKYO) -- After workers successfully plugged the highly radioactive leak seeping into the Pacific Ocean, a new confidential assessment by the Nuclear Regulatory Commission obtained by The New York Times suggests that the damaged Fukushima Daiichi plant is far from stable.

Fragments of incredibly dangerous nuclear fuel were blown out of the reactors "up to one mile from the units," and then simply bulldozed over to protect workers on site, according to the NRC report.

Until now, flooding the damaged reactors with water has been considered the most efficient cooling method but the latest assessment raises concerns that the water may have introduced a new set of dangerous complications.  U.S. engineers now worry that the enormous amount of water is actually weakening the containment vessels, making them more vulnerable to possible ruptures.

In an effort to avoid the continued spread of radiation and worse, a hydrogen explosion due to the hydrogen and oxygen present in seawater, plant operator Tokyo Electric Power Company announced that it will begin injecting nitrogen into reactor one and likely reactors two and three.  Nitrogen is normally present inside the containment that surrounds the reactor core and can prevent highly combustible hydrogen from exploding as it did three times in the early days after the March 11 disaster.

ABC News contributor and president of Ploughshares Fund, Joe Circinione told ABC News that a hydrogen explosion, while not expected, is not totally out of the question.

"A new hydrogen explosion could happen, there could be a failure of one of the fuel rods, the fuel ponds that could cause a fire and if so, it could be a major release of radiation," said Circinione.

While the newest threat is concentrated on land, nearly 11,500 tons of radioactive sea water is slowly diluting in the Pacific Ocean.  Many worry that migrating fish such as albacore tuna might be contaminated as they make their way from Japan to the Pacific Northwest.

Copyright 2011 ABC News Radio


Radiation Leak Halts Work at Damaged Japanese Reactors

Stockbyte/Thinkstock(TOKYO) -- Work to stabilize the damaged reactors at the Fukushima Daiichi nuclear power plant was halted early Wednesday because radiation leaking from the units made the situation unsafe, Japanese officials said.

Radiation levels started to rise sharply after steam was seen escaping from unit 3 at the plant, which was damaged first by the powerful earthquake and tsunami that struck Japan Friday, and then by an explosion in the reactor.

There have been explosions in two other reactors at the plant, and two fires at a fourth unit, which was being used as a storage facility for radioactive material.

A Japanese government official also indicated for the first time that the containment vessels of all three of the reactors at the plant that exploded may be leaking, raising worries of dangerous radiation leaks.

Both the release of steam and the work stoppage came after firefighters extinguished a fire at the plant's unit 4.

The International Atomic Energy Agency said Tuesday that radiation dose rates of up to 400 millisievert (mSv) per hour had been reported at the Fukushima plant site immediately following one of the explosions. A typical chest X-ray exposes an individual to about 0.02 mSv.

However, after the steam was observed escaping from unit 3, radiation levels rose sharply, a government spokesman said.

Chief Cabinet Secretary Yukio Edano said there was a reading of 1,000 millisieverts before the level began falling again to 600-800 millisieverts per hour, which is still considered unsafe.

"So the workers cannot carry out even minimal work at the plant now," Edano said. "Because of the radiation risk, we are on standby."

Japanese Prime Minister Naoto Kan urged those living from 12 to 19 miles around the plant to stay indoors. The 140,000 people living within 12 miles of the plant have been evacuated. So far, 150 people from that area have tested positive for radiation exposure.

Copyright 2011 ABC News Radio 


Japan Seeks U.S. Help With Nuclear Reactor Emergency

Koichi Kamoshida/Getty Images(TOKYO) -- The Japanese government formally asked the United States' Nuclear Regulatory Commission for help in stabilizing its troubled nuclear reactors in the wake of the country's massive earthquake and tsunami.

The NRC sent two boiling water reactor experts to Japan as part of a team of aid workers to help in the recovery efforts. A series of nuclear reactors continue to deteriorate at the Fukushima Daiichi plant, raising worries of a nuclear meltdown.

After two hydrogen explosions in three days at the Fukushima Daiichi plant, a third reactor has lost its ability to cool. Officials are increasingly concerned about unit 2 at the plant.

"They continue to work hard to raise the water level to cover the fuel. Let's pray again," Tatsujiro Suzuki, vice chairman of Japan's Atomic Energy Commission, posted on Facebook Monday.

The fuel rods on unit 2 have been fully exposed for the second time Monday, a dangerous development in the effort to stop the reactor from melting down. The exposure of the fuel rods means that the temperature in the reactor is likely to rise, which will allow it to make steam. The steam could lead to the creation of hydrogen and cause another explosion, experts said.

Knowing how long the fuel rods have been exposed is key to understanding if there is a real chance of a meltdown, said Dr. Peter Hosemann, a nuclear energy expert and professor at the University of California at Berkeley.

Japanese officials acknowledged that the fuel rods appear to be melting inside all three of the reactors at the Fukashima plant.

Copyright 2011 ABC News Radio


Emergencies at 5 Japanese Nuclear Reactors; Radiation Spikes at Most-Affected Site

Koichi Kamoshida/Getty Images(TOKYO) -- Radiation inside a Japanese nuclear reactor surged to 1,000 times its normal level after Friday's 8.9-magnitude earthquake knocked out power to a cooling system, and tsunami floods have hampered efforts to get it restored.

It was one of five Japanese nuclear reactors that lost cooling ability, prompting a race against the clock to install fixes.

In the worst case, at the Fukushima Daiichi power plant's No. 1 reactor, heat-induced pressure built up inside the crippled reactor, prompting widespread evacuations within a 10 kilometer radius and stoking fears of a potentially catastrophic radioactive event.

Officials declared a "nuclear emergency" at the plant, about 200 miles northeast of Tokyo, amid the cooling system failure after the No. 1 reactor lost power and automatically shut down.

Scientists said that even though the No. 1 reactor at the Fukushima Daiichi site, in particular, had stopped producing energy, its fuel continued to generate heat and needed steady levels of coolant to prevent it from overheating and triggering a dangerous cascade of events.

A meltdown could lead to a breach of the reactor's steel containment vessel and allow radiation to escape into an outer, concrete containment building, or even into the environment.

Japanese officials said radiation has not yet leaked from the Fukushima Daiichi plant, but ordered 2,800 people living around the facility to evacuate their homes as a precaution.

The Kyodo News Service has reported, however, that some radioactive material may already have escaped, citing reports from the Japanese Nuclear Safety Agency that radiation levels outside the plan have been eight times the normal level. Experts said that level of exposure is not dangerous to the general population.

Copyright 2011 ABC News Radio 

ABC News Radio