Tonnes of radioactive water was discovered to have leaked into the ground from the Fukushima nuclear plant, Japan's nuclear watchdog said on Tuesday. About 15 tonnes of water with a low level of radiation leaked from a storage tank at the plant, on the Pacific coast 240 km (150 miles) north of Tokyo, the Nuclear and Industrial Safety Agency said. Plant operator Tokyo Electric Power Co said it was still investigating the cause of the leak, which was repaired
after being discovered around noon on Tuesday. Vast amounts of water contaminated with varying levels of radiation have accumulated in storage tanks at the plant after being used by the utility to cool reactors damaged when their original cooling systems were knocked out by the March 11 earthquake and tsunami. Tepco is trying to use a decontamination system that cleans radioactive water so it can be recycled to cool the reactors, but has encountered technical glitches.
Tokyo Electric Power Co. played down concern a solution to its nuclear crisis may be delayed, one day after finding more radiation than expected must be removed from millions of gallons of water before work can proceed on a shutdown. Decontamination efforts at the Fukushima Dai-ichi plant were halted yesterday after a filter expected to remove the radioactive element cesium for several weeks exceeded capacity in just five hours. Oil and sludge in the water contained more radiation than expected,
said Junichi Matsumoto, a spokesman for the utility. “The entire cooling process has been suspended because of the shutdown of the water decontamination system,” Matsumoto said at a media briefing in Tokyo today. “We’re still looking for a solution, but this won’t delay step one of the road map, in which we try to achieve stable cooling status by mid-July.” Decontamination of about 105 million liters (28 million gallons) of water in basements and trenches at Fukushima Dai- Ichi was halted after the level of cesium in a filtering unit reached 4.7 millisieverts of radiation, Matsumoto said yesterday. The units generally need replacement at a level of 4 millisieverts, and the company had expected the unit to last about a month, he said.
‘Simple System’
“Tepco should have had a very simple water decontamination system of its own,” said Tadashi Narabayashi, a nuclear engineering professor at Hokkaido University. “Then, it’s easy to fix or replace a troubled part by themselves.” The utility, known as Tepco, on April 17 outlined plans to end within six to nine months the world’s worst nuclear crisis since Chernobyl in 1986. The first stage is to reduce radiation levels at the plant within three months and then achieve a so- called cold shutdown where reactor temperatures fall below 100 degrees Celsius (212 degrees Fahrenheit). Tepco said today it will vent pressure from the No.2 reactor building to aid cooling and keep on schedule the first phase of progress. There will be “limited impact” on the environment from this, Matsumoto said. The Fukushima plant suffered three reactor meltdowns after the March 11 earthquake and tsunami knocked out power and backup generators, crippling its cooling systems. Japan in April raised the severity rating of the crisis to 7, the highest on an international scale and the same as the Chernobyl disaster. Tepco has been criticized for its slow response to the accident and for publishing erroneous radiation data, while the government-run Nuclear and Industrial Safety Agency has been blamed for not ensuring the utility heeded warnings that a tsunami could overwhelm the plant’s defenses.
What Went Wrong
The utility is now the subject of study by Yotaro Hatamura, appointed by Prime Minister Naoto Kan last month to head a 10- member team conducting an “impartial and multifaceted” investigation into what went wrong and how to prevent a repeat. Hatamura told reporters in Tokyo last week that plant manager Masao Yoshida, said he couldn’t imagine such a huge tsunami. “From our discussions, I gathered that no one at the plant could imagine that such a tsunami would occur,” Hatamura said.
Compensation
While it struggles to shut down the reactors Tepco is also preparing to compensate victims of the disaster, including 50,000 households displaced because of radiation leaks. Japan’s Cabinet on June 14 approved a disaster compensation bill to help the utility pay reparations. The nation’s largest banks and insurers, including Sumitomo Mitsui Financial Group Inc. and Dai-ichi Life Insurance Co., will provide short-term operating funds to Tokyo Electric, according to local media reports. Japan’s government is discussing plans for a fund of several hundred billion yen to finance reconstruction and support families and companies in the disaster-hit prefectures of Fukushima, Miyagi and Iwate, the Nikkei newspaper reported today. Fukushima Governor Yuhei Sato reiterated his opposition to restarting Tepco’s nuclear reactors in the prefecture, the Asahi newspaper reported today. Sato said he will respect and adhere to the denuclearization outline of a prefectural committee on reconstruction, the newspaper reported. Municipal authorities in Fukushima City have expanded radiation monitoring to 1,045 spots, from 100 observed earlier, the Yomiuri newspaper reported yesterday.
Supply ‘Gap’
Trade Minister Banri Kaieda yesterday said he may let utilities restart nuclear generators that had been shut for routine maintenance. There are negatives to suspending all nuclear power, Kaieda said at a press briefing in Tokyo, citing an expected “gap” in power supply and demand in Japan’s coming summer months. Hatamura indicated his team will probe whether an earthquake-prone country such as Japan should build its energy policy around nuclear plants. Because of the inherent dangers, it’s a mistake to treat the industry as safe, he said.
A HUGE floating structure to hold radioactive water has been berthed at the quay of Japan's disaster-hit Fukushima Daiichi nuclear power plant.
The plant's operator, Tokyo Electric Power Company, says the pontoon-type structure is 136 metres long, 46 metres wide and three metres high and can hold 10-thousand tonnes of water.
90-thousand tonnes of contaminated water has been stored at the facility.
Cooling systems at the Fukushima plant were knocked out when a massive 9.0-magnitude earthquake and monster tsunami struck in March.
Japan's government and the owner of the damaged Fukushima Daiichi nuclear power plant are reviewing efforts to wind down the two-month crisis as thousands of nearby residents await word regarding planned evacuations.
Plant workers are making step-by-step progress toward restoring normal cooling, the Tokyo Electric Power Co. said.
Nearly 80,000 people have spent two months away from their homes in the 20-kilometer (12.5-mile) zone around the plant, while tens of thousands more are awaiting orders to evacuate more distant towns where radiation levels are likely to raise the long-term cancer risk.
In the city of Fukushima, displaced residents berated Tokyo Electric President Masataka Shimizu and other top utility executives, who asked for forgiveness in their hands and knees Tuesday. About 100 residents from the village of Kawauchi were allowed to return home for a short visit.
They were issued protective gear, allowed to pack one small bag and spend two hours in their homes. Some returned to find pets -- left behind in the initial confusion -- dead of starvation, Japan's Environment Ministry reported Wednesday.
Private animal-rescue groups had mounted expeditions into the evacuation zone to rescue pets before the government began enforcing the restricted area in late April. Government officials plan to retrieve other pets Wednesday, the ministry said.
Residents of several cities and towns outside the 20-km zone have been told to be ready to move by mid-May. They were put on notice in April that evacuation orders would be coming in about a month, and about a third have already left, government spokesman Noriyuki Shikata said Wednesday.
"It depends on the circumstances of individuals," Shikata said. "It's a bit difficult to get the most updated figure, but I understand that over half the original residents are still residing in the zone."
Tokyo Electric and Japanese nuclear regulators have been trying to wind down the crisis at Fukushima Daiichi since March 11, when the massive earthquake and tsunami that struck northern Japan's Tohoku region knocked out the plant's cooling systems. The result was the world's worst nuclear accident since Chernobyl, compounding a natural disaster of historic proportions.
Japan will mark two months since the earthquake and tsunami with a moment of silence Wednesday. While no deaths have been attributed to the Fukushima Daiichi accident, the earthquake and tsunami have killed nearly 15,000 and left 10,000 more missing, Japan's National Police Agency reported.
In early April, Tokyo Electric announced a six- to nine-month plan to bring the nuclear crisis to an end by restoring normal cooling systems and fully shutting down the reactors. That plan is being reviewed by the utility and the government, and its results are expected to be announced in mid-May, Tokyo Electric spokesman Hiro Hasegawa said Wednesday.
Tokyo Electric has "a number of balls in the air" as it tries to wind down the crisis, said Margaret Harding, a nuclear engineer and former executive at reactor designer General Electric.
"We want them going in with a well thought-out plan that will succeed, because failure here is really not something any of us want them to have happen," Harding said.
The three operating reactors at Fukushima Daiichi overheated, massive hydrogen explosions blew apart the buildings housing units 1 and 3 and another suspected hydrogen blast is believed to have damaged the No. 2 reactor. Engineers have been pouring hundreds of tons of water a day into the reactors since as an emergency measure, and
have also struggled to keep spent fuel pools in units 1, 3 and 4 from overheating.
Huge quantities of radioactive materials spewed from the plant, prompting Japan to declare the accident a top-scale event on the international rating system for nuclear disasters. Thousands of tons of radioactive water have flooded the basements where the cooling systems were housed, making it impossible for workers get into the facilities.
Workers have been able to install air filters inside the No. 1 reactor building to limit the further release of radioactive particles and have begun filling the primary containment shell around the reactor core with water to cover the now-exposed fuel rods, said Yoshikazu Nagai, another spokesman for Tokyo Electric.
The plan will be to recirculate that water through a heat exchanger to cool it, then send it back into the reactor, Nagai said -- essentially building a new cooling system. Similar plans are being considered for unit 2, which is believed to be leaking radioactive water, and 3, where engineers noted a disturbing rise in the reactor's temperature readings last week.
"First we have to tackle unit No. 1, and we need to see if we can succeed," Nagai told CNN.
Equipment that will be used to decontaminate the stagnant, radioactive water pooling in the plant's basements is expected to arrive by mid-May, he said.
The spent but still-energetic fuel assemblies housed in pools of water at the reactor sites remain a concern, however. Water samples taken Sunday from the No. 3 spent fuel pool showed a sharp spike in levels of radioactivity after finding negligible concentrations of reactor byproducts such as radioactive iodine and cesium the previous week, the company reported.
A previous increase in radiation levels in the unit 4 spent fuel pool was blamed on radioactive debris falling into that pool, which was exposed by damage to the reactor building. But the cause of Sunday's reading was unknown, Nagai said.
Meanwhile, Japanese Prime Minister Naoto Kan says his government will rethink its plans for nuclear energy "from scratch" as a result of the disaster.
"Under the basic plan for energy in 2030, the proportion of nuclear energy and total electricity supply would be 50% for nuclear energy and 20% renewable energy," Kan told reporters Tuesday. "But with the occurrence of a major nuclear disaster, the basic plan for energy is going to have to be reviewed thoroughly, from scratch."
Alternative sources of energy like biomass, wind and solar "should be regarded as one of the major pillars" in a new plan, Kan said, and conservation efforts will be ramped up.
In addition, after years of complaints from anti-nuclear activists, his government called on Japanese utility Chubu Electric to shut down the Hamaoka nuclear power plant southwest of Tokyo. The facility sits on a fault line that Japan's science ministry says has an 87% chance of producing a massive earthquake within the next three decades.
Chubu Electric said it would suspend operations at Hamaoka "until further measures" are completed to protect the plant from a tsunami like the one that crippled Fukushima Daiichi .
Whilst the footage, captured by a "packbot", confirmed that electricity and water supplies inside the reactor were undamaged, monitoring equipment showed that radiation levels were far higher than expected.
The Tokyo Electric Power Company (TEPCO) said it will combat the danger by installing fans with filters at the damaged reactor in an attempt to reduce radiation inside to one-twentieth of current levels.
TEPCO has said it may take the rest of the year to bring the nuclear plant back under control.
The company want a "cold shutdown" of the earthquake and tsunami hit plant, 240km (150 miles) from the capital, within six to nine months, a timeline experts say will be tough to meet.
The magnitude 9.0 quake and resulting tsunami knocked out the cooling systems at the power station, causing all four reactors to overheat and leak radiation.
Radiation readings at Japan’s Fukushima Dai-Ichi station rose to the highest since an earthquake and tsunami knocked out cooling systems, impeding efforts to contain the worst nuclear crisis since Chernobyl.
Two robots sent into the reactor No. 1 building at the plant yesterday took readings as high as 1,120 millisierverts of radiation per hour, Junichi Matsumoto, a general manager at Tokyo Electric Power Co., said today. That’s more than four times the annual dose permitted to nuclear workers at the stricken plant.
Radiation from the station, where four of six reactors have been damaged by explosions, has forced the evacuation of tens of thousands of people and contaminated farmland and drinking water. A plan to flood the containment vessel of reactor No. 1 with more water to speed up emergency cooling efforts announced yesterday by the utility known as Tepco may not be possible now.
“Tepco must figure out the source of high radiation,” said Hironobu Unesaki, a nuclear engineering professor at Kyoto University. “If it’s from contaminated water leaking from inside the reactor, Tepco’s so-called water tomb may be jeopardized because flooding the containment vessel will result in more radiation in the building.”
The cores in reactors 1, 2 and 3 and the spent fuels rods in reactor 4 have been damaged. Tepco has been using fire trucks, concrete pumps and other emergency measures for nearly seven weeks to pour millions of liters of water to cool the units after the accident.
Packpots Go In
Tepco shares fell 3.3 percent to 412 yen today in Tokyo. The shares are down about 80 percent since the quake and tsunami struck on March 11, leaving almost 26,000 people dead or missing.
Reactors 1 and 2 are less damaged than estimated, Tepco said in a statement today.
As much as 55 percent of the No. 1 reactor core at the Fukushima Dai-Ichi station was damaged after the March 11 earthquake and tsunami, compared with its earlier estimate of 70 percent.
The assessment for the No. 2 reactor was cut to 25 percent from 35 percent, while that for the No. 3 unit was raised to 30 percent from 25 percent.
“We revised the core damage data because some readings on the containment vessel monitors were wrong,” Matsumoto said when asked about the reassessment. “There was also a recording mistake. We are investigating why this happened.”
Radiation in Tokyo’s water supply fell to undetectable levels for the first time since March 18, the capital’s public health institute said today.
The level of iodine-131 in tap water fell to zero yesterday, and Cesium-134 and cesium-137 also weren’t detected, the Tokyo Metropolitan Institute of Public Health said today.
Tokyo residents were told on March 23 that the city’s water was unsafe for infants after iodine and cesium levels exceeded guidelines.
Japan has decided to raise its assessment of the accident at the crippled Fukushima Daiichi nuclear power plant to the worst rating on an international scale, putting the disaster on par with the 1986 Chernobyl explosion, the Japanese nuclear regulatory agency said on Tuesday.
The decision to raise the alert level to 7 from 5 on the scale amounts to an admission that the accident at the nuclear facility, brought on by the March 11 earthquake and tsunami, is likely to have substantial and long-lasting consequences for health and for the environment. Some in the nuclear industry have been saying for weeks that the accident released large amounts of radiation, but Japanese officials had played down this possibility.
The new estimates by Japanese authorities suggest that the total amount of radioactive materials released so far is equal to about 10 percent of that released in the Chernobyl accident, said Hidehiko Nishiyama, deputy director general of Japan’s nuclear regulator, the Nuclear and Industrial Safety Agency.
Mr. Nishiyama stressed that unlike at Chernobyl, where the reactor itself exploded and fire fanned the release of radioactive material, the containments at the four troubled reactors at Fukushima remained intact over all.
But at a separate news conference, an official from the plant’s operator, Tokyo Electric Power Company, said, “The radiation leak has not stopped completely and our concern is that it could eventually exceed Chernobyl.”
On the International Nuclear Event Scale, a Level 7 nuclear accident involves “widespread health and environmental effects” and the “external release of a significant fraction of the reactor core inventory.” The scale, which was developed by the International Atomic Energy Agency and countries that use nuclear energy, leaves it to the nuclear agency of the country where the accident occurs to calculate a rating based on complicated criteria.
Japan’s previous rating of 5 placed the Fukushima accident at the same level as the Three Mile Island accident in Pennsylvania in 1979. Level 7 has been applied only to the disaster at Chernobyl, in the former Soviet Union.
“This is an admission by the Japanese government that the amount of radiation released into the environment has reached a new order of magnitude,” said Tetsuo Iguchi, a professor in the department of quantum engineering at Nagoya University. “The fact that we have now confirmed the world’s second-ever level 7 accident will have huge consequences for the global nuclear industry. It shows that current safety standards are woefully inadequate.”
Mr. Nishiyama said “tens of thousands of terabecquerels” of radiation per hour have been released from the plant. (The measurement refers to how much radioactive material was emitted, not the dose absorbed by living organisms.) The scale of the radiation leak has since dropped to under one terabecquerel per hour, the Kyodo news agency said, citing government officials.
The announcement came as Japan was preparing to urge more residents around the crippled nuclear plant to evacuate, because of concerns over long-term exposure to radiation.
The authorities have already ordered people living within a 12-mile radius of the plant to evacuate, and recommended that people remain indoors or avoid an area within a radius of about 19 miles.
The government’s decision to expand the zone came in response to radiation readings that would be worrisome over months in certain communities beyond those areas, underscoring how difficult it has been to predict the ways radiation spreads from the damaged plant.
Unlike the previous definitions of the areas to be evacuated, this time the government designated specific communities that should be evacuated, instead of a radius expressed in miles.
The radiation has not spread evenly from the reactors, but instead has been directed to some areas and not others by weather patterns and the terrain. Iitate, one of the communities told on Monday to prepare for evacuation, lies well beyond the 19-mile radius, but the winds over the last month have tended to blow northwest from the Fukushima plant toward Iitate, which may explain why high readings were detected there.
A fresh round of tremors, including one with a magnitude of 6.3, shook northern Japan on Tuesday afternoon, the Japan Meteorological Agency reported.
The quake was centered in Fukushima Prefecture, near Japan's Pacific coast and about 64 kilometers (40 miles) southwest of the crippled Fukushima Daiichi nuclear power plant. Workers retreated to earthquake-resistant shelters during the event, but there was no loss of power at the plant, the Tokyo Electric Power Company told CNN.
It followed a magnitude-6.4 quake Tuesday morning that killed at least six people when it triggered a landslide in Iwaki, north of Tokyo.
The earlier quake buried three homes, the Iwaki fire department said. Three people were rescued and hospitalized, and fire officials were working to rescue an unknown number of others believed to be trapped, the department said.
The quake struck at about 8:08 a.m. Tuesday (7:08 p.m. Monday ET), according to the U.S. Geological Survey. It had a depth of about 13 kilometers (8 miles) and was centered about 77 miles east-southeast of Tokyo.
Monday night, one person was killed in Iwaki and several others were trapped when a powerful 6.6-magnitude earthquake triggered landslides there, the fire department said. It happened exactly one month after the country's devastating 9.0-magnitude quake and tsunami.
Since the March 11 disaster, there have been more than 400 aftershocks of magnitude 6.0 or greater.
The earlier quake was centered about 100 miles (164 kilometers) northeast of Tokyo and about 30 miles (50 kilometers) southwest of the nuclear facility, according to the U.S. Geological Survey.
The landslides in Iwaki buried three houses. Police in Fukushima Prefecture initially reported that four people were trapped. The Iwaki Fire Department later said more than four people were trapped, but the exact number was unclear.
TOKYO - Japan's government on Monday told the operator of the crippled Fukushima nuclear plant to move quickly to stop radiation seeping into the ocean as desperate engineers resorted to bath salts to help trace a leak from one reactor. One official has warned it could take months before the nuclear crisis caused by a March 11 earthquake and tsunami is under control. "We need to stop the spread of (contaminated water) into the ocean as soon as possible. With that strong determination, we are asking Tokyo Electric Power Co to act quickly," Chief Cabinet Secretary Yukio Edano told a news conference. He warned that accumulating radiation from a leak that has defied desperate efforts to halt it "will have a huge impact on the ocean". In the face of Japan's biggest crisis since World War Two, one newspaper poll said that nearly two-thirds of voters want the government to form a coalition with the major opposition party and work together to recover from the massive damage from the March 11 earthquake and tsunami. Underlining the concern over the impact on the world's third largest economy, a central bank survey showed that big manufacturers expect business conditions to worsen significantly in the next three months, though they were not quite as pessimistic as some analysts had expected. An aide to embattled Prime Minister Naoto Kan said on Sunday that the government's priority now was to stop radiation leaks from the Fukushima nuclear plant, 240 km north of Tokyo, and that the situation had "somewhat stabilised".
"How long will it take to achieve (the goal of stopping the radiation leaks)? I think several months would be one target," said Goshi Hosono, a ruling party lawmaker and aide to Kan.
In their desperation, engineers at plant operator Tokyo Electric Power Co (TEPCO) have used anything to hand to try to stop the leaks. At the weekend, they mixed sawdust and newspapers with polymers and cement in a so far unsuccessful attempt to seal the crack in a concrete pit at reactor no.2, where radioactive water has been flowing into the sea. On Monday, they resorted to powdered bath salts to produce a milky color to help trace the source of the leak. TEPCO is planning to put some sort of curtain into the sea by the nuclear plant to try to prevent radioactive water spreading further into the ocean. It has not decided what material to use. The government has said three of the six Fukushima reactors were now generally stable. At least four will eventually be scrapped but that could take decades.
The president of the embattled utility that owns the crippled Fukushima Daiichi nuclear plant has been hospitalized due to "fatigue and stress," the company said Wednesday.
Tokyo Electric Power Co. President Masataka Shimizu was hospitalized Tuesday. The company has not released further details about his condition.
Shimizu made a public apology several days after a March 11 earthquake and tsunami knocked out cooling systems at the plant. The last time he was spotted in public was at a March 13 news conference.
Reporters peppered company officials with questions about the president's whereabouts Sunday. A spokesman said Shimizu had been staying inside the company's Tokyo headquarters.
His physical condition had been on the decline from overwork, the spokesman said Sunday.
News of Shimizu's hospitalization comes a day after an inspector for Japan's nuclear safety agency described austere working conditions at the plant.
Workers were sleeping in conference rooms, corridors, and stairwells on leaded mats intended to keep radiation at bay, safety inspector Kazuma Yokota said.
They were also eating only two meals each day -- a carefully rationed breakfast of 30 crackers and vegetable juice, and for dinner, a ready-to-eat meal or something out of a can.
"My parents were washed away by the tsunami, and I still don't know where they are," one worker wrote in an e-mail that was verified as authentic by a spokesman for the Tokyo Electric Power Co.
"Crying is useless," said another e-mail. "If we're in hell now, all we can do is crawl up towards heaven."
In a statement released March 18, Shimizu said the company was taking the crisis seriously.
"We sincerely apologize to all the people living in the surrounding area of the power station and people in Fukushima Prefecture, as well as to the people of society for causing such great concern and nuisance," he said.
Meanwhile, tests revealed radioactive iodine at more than 3,000 times the normal level in ocean water near the plant -- a new high, Japan's nuclear safety agency said Wednesday.
The Nuclear and Industrial Safety Agency said monitoring data collected Tuesday afternoon detected the I-131 isotope at 3,355 times the normal level.
The sample was taken 330 meters (1,080 feet) away from one of the plant's water discharge points, the agency said.
Radiation readings from seawater outside the plant have fluctuated. They spiked Sunday, then dropped a day later.
Officials did not pinpoint a particular cause for the higher readings.
But officials and experts have noted that workers at the plant face a difficult balancing act as they struggle to keep reactors cool and prevent radioactive water from leaking into the ocean.
Water has been a key weapon in the battle to stave off a meltdown at the facility. Workers have pumped and sprayed tons of water to keep the plant's radioactive fuel from overheating, and the plant is running out of room to store the now-contaminated liquid.
"They have a problem where the more they try to cool it down, the greater the radiation hazard as that water leaks out from the plant," said Jim Walsh, an international security expert at the Massachusetts Institute of Technology.
Despite occasional sightings of smoke and steam billowing from damaged reactor buildings at the Fukushima-1 nuclear power plant in Japan, the effort has resumed to restore electricity and critical cooling functions. Radiation continues to be detected above normal
levels as far as 300 kilometers south of the facility, which was knocked out of commission by a huge quake and tsunami nearly two weeks ago.
After a break, because of concerns about smoke and radioactive steam, workers at the Fukushima-1 nuclear power plant on Thursday resumed the attempts to repair the cooling system at the Number 3 reactor.
That is the considered to be the most dangerous unit, because its fuel contains a mix of uranium and plutonium.
Video taken from a helicopter Thursday morning shows what appears to be steam rising from four of the nuclear facility's six reactor buildings. However, authorities say the situation is not serious enough to continue a halt in the critical work to prevent a potentially larger catastrophe.
A re-emergence of black smoke at the Number 3 reactor halted work Wednesday.
There is also fresh concern about the damaged Number 1 reactor where pressure inside the reactor again increased.
Japan's chief cabinet secretary Yukio Edano says crews are trying to maintain a delicate balance between spraying water on the radioactive fuel, which causes a rise in pressure, and reducing the water flow which could see temperatures increase to a dangerously high level.
Edano says experts are watching the situation closely and there is no evidence that the reactor vessel has been damaged by excessive pressure.
Since the March 11 magnitude 9.0 earthquake, which triggered a destructive tsunami, the nuclear power complex has experienced many serious problems. These include hydrogen explosions in reactor buildings, radiation leaks, exposed and overheating fuel rods, damaged reactor cores and shaking from powerful aftershocks.
Tokyo Electric Power Company, the plant operator, has also revealed that it spotted 13 times, between March 13 and 16th, a radioactive "neutron beam" about 1.5 kilometers from the Number 1 and 2 reactors.
Some scientists say this means uranium and plutonium might have leaked from the plant's nuclear reactors and the exposed used nuclear fuel rods have discharged a small amount of neutron beams via fission.
James Symons, the director of the nuclear science division at the Lawrence Berkeley National Laboratory in California, expresses surprise and skepticism about the report.
"A neutron beam would be a beam of neutrons, which are a neutral particle. They are certainly produced in a fission reaction inside a reactor. But if neutrons escape and were to come out of the reactor they would not be visible. So you would not see a neutron beam," he said. "Plus Ican't imagine a process in which neutrons would be emitted from the reactor in a beam."
The physicist says, at this stage, the Fukushima disaster has more in common with 1979 Three Mile Island partial meltdown, in the United States, than the 1986 Chernobyl catastrophe in Ukraine.
"All these things are different. But it's closer," said Symons. "It's certainly very unlike what happened at Chernobyl where the entire reactor exploded basically. It's certainly very serious, but - as far as we can tell - it's also coming under control."
Radiation continues to be detected in the surrounding air, soil and sea water.
Japan's government is now advising people beyond the 30-kilometer exclusion zone around the Fukushima plant to remain indoors. Officials say that, since the explosions, some infants theoretically may have accumulated 100 millisieverts of radiation in their thyroids.
Some scientists say those exposed to that total radiation dose should take potassium iodide, because an annual dose of 100 millisieverts is believed to be associated with an increased risk of cancer.
Japan's science ministry says radiation levels detected in Tokyo have tripled, compared to those detected earlier in the week.
The Tokyo metropolitan government, as well of those of the adjacent prefectures of Chiba and Saitama, have announced levels of radioactive iodine considered unsafe for infants were detected this week in tap water.
That has prompted panic buying of bottled water.
Vegetable shipments have been stopped out of areas adjacent to the crippled nuclear power plant after some leafy greens were found to be contaminated with radioactive iodine and cesium exceeding government standards.
TOKYO—Fear about radiation dangers posed by Japan's nuclear crisis spiked as the U.S. instructed its troops and citizens to stay at least 50 miles away from the crippled reactors—establishing a "no-go" zone far wider than the buffer recommended by the Japanese government itself. And in a vivid sign that Japan's leadership is trying to move decisively to take control of the deepening crisis, the nation's military force dispatched two helicopters Thursday morning local time to dump water over the crippled Fukushima Daiichi power complex in hopes of taming its dangerously overheating nuclear facilities. The effort targeted a pool of spent nuclear fuel at reactor No. 3. Defense Minister Toshimi Kitazawa said the water would help cool the spent fuel, lessening the risk of a catastrophic fire, if the water hit its target.
Mr. Kitazawa also said 11 water-cannon trucks were to be deployed at the plant Thursday afternoon in a further effort to cool the overheating waste.
Japan's nuclear regulator also announced that it was working to connect outside power cables to two of the units at the stricken plant, in hopes of restarting their cooling pumps. They hoped to have the cables available by Thursday afternoon.
Restarting the pumps would mark a major advance in the effort to prevent the nuclear disaster from worsening.
Japan's widening government involvement came as international skepticism built up. Late Wednesday, the U.S. State Department authorized the voluntary evacuation of dependents of U.S.-government personnel based in northeast Japan. The State Department also added that U.S. citizens in Japan consider departing, and reiterated its caution that citizens defer travel to the country at this time.
Earlier in the day, the top U.S. nuclear regulator, Gregory Jaczko, called radiation levels at one of the plant's units "extremely high," adding that, "for a comparable situation in the United States we would recommend an evacuation for a much larger radius than is currently being provided in Japan."
Previously the U.S. had agreed with Japanese officials that a 12-mile evacuation zone was adequate. The change came after the NRC ran computer-modeling exercises using "the best available information we have" about the damaged reactors along with accumulated knowledge about how systems inside nuclear plants perform under "severe accident conditions," a spokesman with the Nuclear Regulatory Commission said.
Asked why the U.S. set a broader "no-go" zone than did Japan, government spokesmen Yukio Edano said in a press conference that it was understandable to make a more "conservative decision" when trying to ensure the safety of citizens abroad, in a country where it doesn't exert direct control. He reiterated that Japan's government feels it is taking appropriate measures.
Also on Wednesday, the U.K. government advised its citizens in the city of Tokyo, a full 150 miles from the nuclear site, to "consider leaving the area" due to increasing infrastructure problems. The European Union's energy chief, Guenther Oettinger, also declared the Fukushima Daiichi site "effectively out of control." A spokeswoman for Mr. Oettinger later said the commissioner's remarks reflected his own personal views, and weren't based on privileged information.
Stock markets staged large swings, reflecting the depth of anxiety world-wide. "Every investment decision is made through the prism of what is going on in Japan," said Phil Orlando, chief equity strategist at Federated Investors. The Dow Jones Industrial Average closed 2% lower at 11613. Thursday morning, Tokyo shares slid 2.1%.
Late Wednesday, the U.S. Environmental Protection Agency said it was deploying additional radiation monitors out of "an abundance of caution." The EPA already monitors the air for radiation via a national network of approximately 140 stationary and mobile devices. The agency said it sent additional monitors to Alaska and plans to send some to Hawaii.
Officials with the U.S. Nuclear Regulatory Commission and the Energy Department say they don't expect harmful radiation levels to reach the U.S.
As part of the government effort to take on a larger role in the crisis management, on Wednesday plant operator Tokyo Electric Power Co., or Tepco, said 20 government officials had moved into the company's offices as part of a joint crisis headquarters.
The government's use of helicopters to dump water on the site was ordered by Economics Minister Banri Kaieda. "The minister considered the situation to be dangerous and judged there was an imminent necessity to issue the order," said a spokesman for the Nuclear and Industrial Safety Agency, which is part of Mr. Kaieda's purview. "After learning that Tepco was not injecting cooling water, he judged it to be very dangerous."
Two helicopters made two trips each, scooping up tons of seawater in a massive bucket and then trying to dump it into a pool used to store waste-fuel at reactor No. 3. An earlier explosion had blown the roof off of the building, exposing the storage pool and making the helicopter mission possible.
Because of radiation risk, the helicopters had to maintain considerable altitude. A government official said it wasn't yet clear whether the water hit its target.
The race to build an emergency power supply for the crippled plant, combined with details from the early moments of the crisis, highlight new questions about the design and safety record of the facility, which is Japan's oldest.
Common to all nuclear plants is this fundamental design problem: Engineers try to make the equipment impervious to one threat, but that may make it vulnerable to another.
In this case, the Fukushima Daiichi nuclear complex's back-up diesel-powered generators were built below ground level. This bunker-like positioning would protect the generators from an air strike, cyclone or typhoon—but made them more vulnerable to an earthquake-driven tsunami.
When last week's giant waves struck, they immobilized the generators despite being designed to protect against water. The tsunami also apparently washed away the generators' fuel tanks, which were above ground.
"The earthquake and tsunami we had last week both exceeded our engineering assumptions by a long shot," said Tetsuo Ito, head of Kinki University's Atomic Energy Research Institute, near Osaka. "The nuclear industry around the world probably will have to review how we set those assumptions in designing a nuclear power plant."
Another area of scrutiny is the proximity of the plant's six reactors to one another. Damage to one reactor contributed to damage to another, and their proximity hindered a recovery.
This arrangement can be found at other plants, because it can make it easier to move equipment around and helps to keep a smaller work force, said Mr. Ito. But now it looks like a "bad idea," he said. "We need to strike a better balance of operational efficiency and safety."
Terry Pickens, director of nuclear regulatory policy at Xcel Energy Inc. of the U.S., said there is no cookie-cutter reactor of the vintage of the Fukushima units because utilities in those days hired their own engineering firms and architects, and customized the plants' designs. At Xcel's Monticello plant in Minnesota, diesel generators are kept as far apart as possible so that "a natural phenomenon isn't likely to take both of them out," Mr. Pickens said.
The Japanese plant lost power during Friday's earthquake. The three active reactors shut off automatically as designed, but a lack of electricity left workers unable to operate their cooling systems, leading to overheating. Tepco says the tsunami paralyzed all but one backup generator.
In a weekend briefing, Tepco Managing Director Akio Komori cited the elevation of the backup generators as one potential issue. A Tepco spokesman confirmed the remarks, adding that a full probe will have to wait while workers try to bring the reactors under control.
A spokesman for Japan's Nuclear and Industrial Safety Agency, the nation's nuclear-power regulator, said Fukushima Daiichi's emergency-generator design is "fairly prevalent" at other Japanese plants. The spokesman, Shigekatsu Ohmukai, disputed that the elevation of the generators was a problem. The agency, he said, had concluded that the plant could withstand a certain size of tsunami but "obviously the tsunami caused by Friday's earthquake exceeded our assumptions. That's the problem."
Tepco tested the Fukushima Daiichi plant to withstand an earthquake magnitude of 7.9—a level of seismic activity the power company thought wouldn't be surpassed in the area, according to company documents on its website from 2010. The quake that struck Friday, however, was about 10 times as big as that theoretical maximum.
In the U.S., where there are 23 similar reactors operated by 11 different companies, backup generators typically are housed in bunker-like buildings at ground level. They are designed with watertight fittings that are intended to keep out water from floods or hurricanes.
General Electric Co. designed three of the six reactors for Tepco at the Daiichi complex but it didn't determine the layout of every piece of equipment, a company spokesman said. Some of that was done by architects and engineers hired by Tepco. He added that the main problem was the larger-then-expected tsunami, not the generator placement.
The Daiichi plant was central to a falsified-records scandal a decade ago that led Tepco to briefly shut down all its plants and led to the departure of a number of senior executives. Nuclear experts say that led to a number of disclosures of previously unreported problems at the plant.
The tsunami that barreled into northeast Japan on Friday was so murderous and efficient that not much was left when search-and-rescue teams finally reached Natori on Monday. There was searching, but not much rescuing. There was, essentially, nobody left to rescue. The mournful scene here in Natori, a farm and fishing town that has been reduced to a vast muddy plain, was similar to rescue efforts in other communities along the coast as police, military and foreign assistance teams poked through splintered houses and piles of wreckage.The death toll from the 8.9-magnitude quake — the strongest in Japan’s seismically turbulent history — continued to climb, inexorably so, as officials uncovered more bodies. By Monday afternoon, the toll stood at 2,800 but many thousands of people remained unaccounted for and were presumed dead. Police officials said it was certain that more than 10,000 had died. Police teams, for example, found about 1,000 bodies that had washed ashore on a scenic peninsula in Miyagi Prefecture, close to the epicenter of the quake that unleashed the tsunami. The bodies washed out as the tsunami retreated. Now they are washing back in. A string of crippled nuclear reactors at Fukushima also continued to bedevil engineers who were desperately trying to cool them down. The most urgent worries concerned the failures of two reactors at the Fukushima Daiichi nuclear plant, where workers were still struggling to avert meltdowns and where some radiation had already leaked. The building housing Reactor No. 1 exploded on Saturday, and a hydrogen buildup blew the roof off the No. 3 reactor facility on Monday morning. The blast did not appear to have harmed the reactor itself, government and utility officials said, but six workers were injured in the blasts. Later Monday, a company official said Reactor No. 2 was losing cooling function and workers were pumping in water, according to Yukio Edano, the chief government spokesman. The collective anxiety about Japan caused a rout in the Japanese stock market, and the main Nikkei index fell 6.2 percent in Monday’s trading, the worst drop in three years. The broader Topix, or Tokyo Stock Price index, dropped 7.4 percent. Worried about the severe strains on banking and financial systems, the Bank of Japan pumped about $180 billion into the economy on Monday, and the government was discussing an emergency tax increase to help finance relief and recovery work. The Tokyo Electric Power Company, which operates the country’s crippled nuclear power grid, announced plans for rotating blackouts across the region to conserve electricity — the first controlled power cuts in Japan in 60 years. Tokyo residents worriedly followed a series of confusing and apparently contradictory statements about the location and duration of the power cuts. Public conservation of electricity was significant enough, the company said, that the more drastic blackout scenarios were being scaled back. Monday’s explosion at the Daiichi plant was the latest development in what Japan’s prime minister has called the nation’s worst crisis since World War II. Japan’s $5 trillion economy, the third largest in the world, was threatened with severe disruptions and partial paralysis as many industries shut down and the armed forces and volunteers mobilized for the far more urgent effort of finding survivors, evacuating residents near the stricken power plants and caring for the victims of the 8.9 magnitude quake that struck on Friday. The disaster has left more than 10,000 people dead, many thousands homeless and millions without water, power, heat or transportation. The death toll was certain to climb as searchers began to reach coastal villages that essentially vanished under the first muddy surge of the tsunami, which struck the nation’s northern Pacific coast near the port city of Sendai. In one town alone, the port of Minamisanriku, a senior police official said the number of dead would “certainly be more than 10,000.” That is more than half the town’s population of 17,000. Prime Minister Naoto Kan told a news conference in Tokyo late Sunday: “I think that the earthquake, tsunami and the situation at our nuclear reactors makes up the worst crisis in the 65 years since the war. If the nation works together, we will overcome.” The government ordered 100,000 troops — nearly half the country’s active military force and the largest mobilization in postwar Japan — to take part in the relief effort. An American naval strike group led by the nuclear-powered aircraft carrier Ronald Reagan also arrived off Japan on Sunday to help with refueling, supply and rescue duties. The quake and tsunami did not reach Japan’s industrial heartland, although economists said the power blackouts could affect industrial production — notably carmakers, electronics manufacturers and steel plants — and interrupt the nation’s famously efficient supply chain. Tourism was also bound to plummet, as the United States, France and other nations urged citizens to avoid traveling to Japan. AIR Worldwide, a risk consultant in Boston, said its disaster models estimated property damage to be as high as $35 billion. The company said 70 percent of residential construction in Japan was wood, and earthquake insurance was not widely used. Amid the despair and the worry over an unrelenting series of strong aftershocks, there was one bright moment when the Japanese Navy rescued a 60-year-old man who had been floating at sea for two days. The man, Hiromitsu Arakawa, clung to the roof of his tiny home in the town of Minamisoma after it was torn from its foundations by the first wave of the tsunami, the Defense Ministry said. He saw his wife slip away in the deluge, but he hung on as the house drifted away. He was discovered late Sunday morning, still on his roof, nine miles south of the town and nine miles out to sea. The quake was the strongest to hit Japan, which sits astride the “ring of fire” that designates the most violent seismic activity in the Pacific Basin. About 80,000 people were ordered to evacuate danger zones around the two compromised atomic facilities in Fukushima Prefecture. Japanese officials reported that 22 people showed signs of radiation exposure and as many as 170 were feared to have been exposed, including some who had been outside one of the plants waiting to be evacuated. Three workers were suffering what officials described as full-blown radiation sickness. In a televised address the trade minister, Banri Kaieda, asked businesses to limit power use as they returned to operation on Monday. He asked specifically for nighttime cutbacks of lights and heating. The power company said the blackouts would affect three million customers, including homes and factories. The Japan Railways Group cut operations at six of its commuters lines and two bullet trains to 20 percent of normal to conserve electricity. Tokyo and central Japan continued to be struck by aftershocks off the eastern coast of Honshu Island. A long tremor registering 6.2 caused buildings in central Tokyo to sway dramatically on Sunday morning. Search teams from more than a dozen nations were bound for Japan, including a unit from New Zealand, which suffered a devastating quake last month in Christchurch. A Japanese team that had been working in New Zealand was called home. A combined search squad from Los Angeles County and Fairfax County, Va., arrived from the United States with 150 people and a dozen dogs that would help in the search for bodies. Assistance teams were also expected from China and South Korea, two of Japan’s most bitter rivals. Tokyo’s acceptance of help — along with a parade of senior officials who offered updates at televised news conferences on Sunday — was in marked contrast to the government’s policies after the 1995 Kobe earthquake, which killed more than 6,000 people. Japan refused most offers of aid at the time, restricted foreign aid operations and offered little information about the disaster. In Sendai, a city of roughly a million people near the center of the catastrophe, many buildings cracked but none had collapsed. Still, city officials said that more than 500,000 households and businesses were without water, and many more lacked electricity as well. Soldiers surrounded Sendai’s city hall, where officials were using two floors to shelter evacuees and treat the injured, using power drawn from a generator. Thousands of residents sought refuge inside and waited anxiously for word from their relatives. A line of people waited outside with plastic bottles and buckets in hand to collect water from a pump. Masaki Kokubum, 35, has been living at the city hall since the quake. He had worked at a supermarket, and his neighborhood lost power and water. He said he had not slept in three days. “I can’t sleep,” he said as he sat in a chair in a hallway. “I just sit here and wait.”
Japanese efforts to prevent a nuclear meltdown by flooding reactors with seawater are a last-ditch attempt, but do not mean that a nuclear tragedy is imminent, experts said Sunday. Nuclear experts who have followed the developments at the damaged Fukushima Daiichi nuclear plant in northeastern Japan say that despite several setbacks, the possibility of massive radiation exposure remains low -- at least for now. Meanwhile, a state of emergency has been declared at a nuclear power plant in Onagawa, Japan, where excessive radiation levels have been recorded following Friday's massive earthquake, the United Nations' atomic watchdog agency said Sunday. Authorities have told the agency that the three reactor units at the Onagawa plant "are under control." "I don't think we're really close to a meltdown," said Dale Klein, vice chancellor for special engineering projects at the University of Texas, referring to the Daiichi plant. There does appear to be some fuel damage to one of the reactors, but the seawater method to keep them cool seems to be working. "I think when the dust all settles, the death toll from the tsunami and the earthquake will be much more significant than any damage from these reactors," he said. The use of seawater shows that authorities are giving up future use of the Daiichi plant and are focusing solely on protecting people and the environment, experts said. "If they are (using seawater), it's because they have no other choice," said James Walsh, a research associate at the security studies program at MIT. "The last thing you want to do is pump seawater and boron into a reactor." The salt and boron will corrode the reactor, he said. "Essentially, they are saving the white flag and saying, 'This plant is done,' " Walsh said. "This is a last-ditch mechanism to try to prevent overheating and to prevent a partial or full meltdown." In addition, danger from any radiation that escapes would vary on a number of factors, including the type of radiation, the amount and geography, he said. The use of the seawater reflects the seriousness of the damage, said James Acton of the nuclear policy program at The Carnegie Endowment. "You're only going to do that if you're seriously worried about the possibility of significant core meltdown," he said. He added that the word "meltdown" can mean a lot of different things, depending on its severity. "So there's both significant uncertainty about what's going on at the moment, and significant uncertainty about the possible outcomes," Acton said. A major explosion of a reactor at the Daiichi plant is "almost inconcievable," he said. "I think that worst-case outcome is unbelievably unlikely in this case." At the Daiichi nuclear plant, workers have been scrambling to cool off fuel rods at both reactors after the massive earthquake and tsunami disabled their cooling systems. Japanese authorities have said there is a "possibility" that a meltdown has occurred in the reactors. A meltdown is a catastrophic failure of the reactor core, with a potential for widespread radiation release. But Japanese officials stressed that there were no indications of dangerously high radiation levels in the atmosphere around the two reactors at the Fukushima Daiichi nuclear plant in northeastern Japan. They said they were unable to confirm whether a meltdown had occurred because they cannot get close enough to the reactors' cores. "We are continuing to monitor the radiation, but it is under control," Edano told reporters. Later Sunday, a spokesman for Japan's prime minister repeated that assertion and said he would not describe what was occurring in the reactors as a "meltdown." "The situation is under control. ....We have been succeeding in lowering pressure inside the containment vessel," spokesman Noriyuki Shikata said. The aftermath of the devastating earthquake -- from the scores of casualties to the nuclear concerns at the plant in Fukushima prefecture -- marks the "toughest and most difficult crisis for Japan" since the end of World War II, Japanese Prime Minister Naoto Kan said Sunday. Chief Cabinet Secretary Yukio Edano said an explosion could take place in the building housing the No. 3 reactor at the Daiichi plant. "There is a possibility that the third reactor may have hydrogen gas that is accumulating in the reactor (that) may potentially cause an explosion," he said. An explosion caused by hydrogen buildup Saturday blew the roof off a concrete building housing the plant's No. 1 reactor, but the reactor and its containment system were not damaged in the explosion. Edano said the No. 3 reactor would also likely withstand a similar blast, noting that workers had already released gas from the building to try to prevent an explosion. Meanwhile, the prime minister ordered a Tokyo power company to conduct a widespread power outage in an effort to preserve energy as workers try to repair power plants damaged in the earthquake, including nuclear facilities. The Tokyo Electric Power Company has been instructed to conduct three-hour rolling blackouts as the country faces a 10 million kilowatt shortage, officials said. Edano said doctors were examining nine people who tested positive for high radiation levels on their skin and clothing. Meanwhile, he said authorities were responding under the presumption that meltdowns had taken place in both reactors. If the effort to cool the nuclear fuel inside the reactor fails completely -- a scenario experts who have spoken to CNN say is unlikely -- the resulting release of radiation could cause enormous damage to the plant or release radiation into the atmosphere or water. That could lead to widespread cancer and other health problems, experts say. Authorities have downplayed such a scenario, insisting the situation appears under control and that radiation levels in the air are not dangerous. Still, as what they described as "a precaution," more than 200,000 people who live within 20 kilometers (12 miles) of the plant have been ordered to leave the area. "The bottom line is that we just don't know what's going to happen in the next couple of days and, frankly, neither do the people who run the system," added Dr. Ira Helfand, a member of the board of Physicians for Social Responsibility. What we do know, he added, is that Japan's nuclear facilities are "way out of whack." At one medical facility in Koriyama, about one hour from Fukushima, about 1 in 5 people being tested for high radiation levels are being referred to a hospital for further testing. About 1,000 people have been tested so far, officials said. While some analysts said Japanese officials had not informed the public quickly enough about the evolving crisis, Jay Lehr, science director at the Heartland Institute in Chicago, said he was "100% confident" that Japan would be able to solve the problems at its nuclear plants. "Nobody builds better power plants than Japan, because they are the most seismically active country on earth. They are built to withstand this very earthquake," he said. "I am absolutely, 100% confident that they will be able to solve the existing problem of a meltdown, if it is occurring, that they will be able to totally eliminate the escape of any radiation," he said. Robert Apthorpe, a nuclear engineer who has been fielding questions about Japan's nuclear plant problems on Twitter, said Sunday that time is of the essence. "We have to watch very carefully the next 24 to 48 hours. ... We're not out of the woods yet," he said. The problems at the Daiichi plant began Friday, when the 8.9-magnitude quake that struck offshore forced the automatic shutdown of the plant's nuclear reactors and knocked out the main cooling system, according to the country's nuclear agency. A tsunami resulting from the quake then washed over the site, knocking out backup generators. The reactors at the Daiichi plant are boiling-water reactors. The reactor affected by Saturday's explosion is Fukushima Daiichi 1. It was connected to the grid in November 1970, making it about 40 years old. The No. 1 unit is the oldest of six reactors at the Fukushima Daiichi site, according to the World Nuclear Association. Japan is heavily dependent on nuclear power, with 54 plants and another eight slated for construction, said Aileen Mioko Smith of Green Action, an environmental group. All are located in "very seismic" areas, she said. Authorities have also detected cooling system problems at another nuclear facility in Fukushima Prefecture, the Fukushima Daini plant, but have not expressed any concerns about possible meltdowns there. Edano said that there have not been any leaks of radioactive material at either of the affected plants. Authorities deliberately have let out radioactive steam in order to alleviate growing pressure inside both of the affected reactors.
