Archive for the ‘Tsunami’ Category

Officials inspect the damaged building housing the No.3 reactor at Fukushima Daiichi nuclear power plant on June 17, 2011  
Officials are not yet sure if the readings pose a problem
A radioactive gas has been detected at Japan’s crippled Fukushima nuclear plant, the facility’s operator says.

Tepco said xenon had been found in reactor two, which was previously thought to be near a stable shutdown.

There has been no increase in temperature or pressure, but the discovery may indicate a problem with the reactor.

Boric acid – used to suppress nuclear reactions – has been injected as a precaution.

Ever since the meltdowns in March triggered by the huge earthquake and tsunami, engineers have been working to bring the Fukushima reactors under control.

The government and Tepco – the Tokyo Electric Power Company – have said they are on track to achieve a stable shutdown by the end of the year.

But now they have found what could be a problem – radioactive xenon gas detected in a filter in reactor two.

Since it has a short half-life, it indicates a possibility of resumed nuclear fission in recent days.

Tepco says the temperature of the reactor, which has been below boiling point, has not increased, indicating any reaction would be small.

It is not ruling out a false reading but boric acid, which suppresses fission, was injected into the reactor overnight.

Meanwhile, elsewhere in Japan a reactor has been switched on for the first time since the disaster.

Safety fears mean local authorities have been refusing permission for restarts after routine maintenance.

Dozens of facilities are offline amid concern about electricity shortages.


Devastation caused by earthquake and tsunami There has been growing discontent in Japan about the government’s handling of the quake and tsunami
Japan’s new Prime Minister Yoshihiko Noda has unveiled his cabinet, which will be charged with rebuilding the country and boosting growth.

Japan has been trying to rebuild after the damage caused by the earthquake and tsunami earlier this year.
At the same time, Japan’s economy is in recession.
Jun Azumi has been appointed finance minister, while Motohisa Furukawa has been given charge of the economics portfolio.
Yoshio Hachiro has been named as the new trade minister by Mr Noda.
Unknown quantity? Mr Noda took over Japan’s top job after his predecessor Naoto Kan resigned following public anger about his handling of March’s quake and tsunami.
A slowdown in Japan’s economy further fuelled feeling against the government.
It meant the decision over who would take charge of key ministries such as finance, economics and trade had been keenly watched.
However, the announcements, especially that of Mr Azumi, who had not been considered a front runner, have raised fresh questions.


Jun Azumi was not the first choice to be finance minister, arguably the toughest job in the new cabinet, according to Japan’s national broadcaster NHK.
That was Katsuya Okada, but the former foreign minister turned it down.
Market reaction to the surprise decision was muted, even though little is known about Mr Azumi’s views on fiscal and currency policy.
The reason is the new Prime Minister Yoshihiko Noda has come to the job from the finance ministry.
He is likely to have chosen a man who agrees with him to be his successor there.
Mr Noda has pushed for sales tax to be doubled by the middle of the decade to try to rein in the massive public debt, although the real challenge will be to persuade reluctant members of the Diet to back the plan.
And he oversaw intervention in the currency markets to try to bring down the record high yen, which hurts Japan’s exporters.

“Appointment of a relatively unknown person raises more questions than answers and heightens a sense of uncertainty,” said Koji Fukaya of Credit Suisse Securities.

Analysts also said they were not sure about his stance on financial policies.
“He [Mr Azumi] has not made many comments about intervention or fiscal policies,” said Ayako Sera of Sumitomo Trust and Banking.
Financial policy The new cabinet will have to hit the ground running given the overall health of the country’s economy, which has now contracted for three consecutive quarters.
At the same time, a rising currency is threatening to cause further damage to the nation’s export-dependent manufacturing sector.
During his time as in charge of the finance ministry in the previous cabinet, Mr Noda had voiced his concerns about the rising currency.
Japanese authorities had intervened twice in the foreign exchange markets in a bid to weaken the currency.
Analysts said that given that Mr Noda has appointed a relatively inexperienced candidate as the finance minister, he was likely to continue with the policies he had put in place.
“If he were a veteran lawmaker, the new finance minister might have clashed with Noda on some issues,” said Koichi Haji of NLI Research Institute.
“But that appears not to be the case and the choice is likely a sign Noda will pursue his own policies on economic and fiscal issues.” he added.
Nuclear power Another key area that the new cabinet needs to address immediately is the power situation in the country.
Japan relies on nuclear power as major source of its electricity supply.
The 11 March earthquake and tsunami caused substantial damage to the Fukushima Daiichi nuclear plant, which resulted in other nuclear power stations in the country being shut down as well.
That resulted in a shortage of power supply which could last for three to five years according to Japan’s former economics minister Kaoru Yosano.
At the same time, radiation leaks at the Fukushima Daiichi plant have raised concerns about the safety of nuclear energy.
Although prime minister Noda has not been as vocal as his predecessor about nuclear energy, he has acknowledged that building new reactors will be next to impossible, given the public’s worries about safety.

A tsunami wave approaches the Fukushima nuclear plant on March 11, 2011

Photo: Courtesy TEPCO
A tsunami wave approaches the Fukushima nuclear plant on March 11, 2011

Japanese nuclear regulators say they were told four days before the March 11 earthquake that the Fukushima nuclear plant could be hit by a far-larger tsunami than it was designed to withstand.

The regulators told reporters Wednesday that the plant’s operators, Tokyo Electric Power Company, determined in 2008 that the plant could be hit by a tsunami more than 10 meters high. But the findings, based on a computer simulation of a major undersea earthquake, were not passed along until March 7 of this year.

The Nuclear and Industrial Safety Agency says it responded to the report by asking for urgent countermeasures at the plant, which was designed to withstand a tsunami of only 5.7 meters. The tsunami that hit the plant four days later is estimated to have been as high as 15 meters.

The 10-meter estimate prepared in 2008 was based on an assumption of an 8.2-magnitude earthquake in the Pacific Ocean east of the plant. The actual earthquake had a magnitude of 9.0, one of the five most powerful ever recorded.

The resulting tsunami destroyed all sources of power to cooling systems at the plant, leading to core meltdowns in three of its six reactors. Workers have been struggling ever since to halt radioactive leakage into the ocean, air and soil around the plant.

A worker points to a crack in a concrete pit near Fukushima Daiichi's No 2 reactor, 2 April The concrete pit near Reactor No 2 was cracked by the quake
A leak of highly radioactive water into the Pacific Ocean from Japan’s crippled Fukushima Daiichi nuclear plant has been stopped, its operator reports.

Tepco said it had injected chemical agents to solidify soil near a cracked pit that was the source of the leak.
Engineers have been struggling to stop leaks since the plant was damaged by the earthquake and tsunami on 11 March.
They are currently discharging less contaminated water into the sea so more radioactive water can be stored.
Since the earthquake knocked out cooling systems, workers have been pumping water into reactors to cool fuel rods, but must now deal with waste water pooling in and below damaged reactor buildings.
Engineers also face a potential new problem of a build-up of hydrogen gas in one of the reactors at the six-unit plant. Tepco said it could inject nitrogen gas into the No 1 reactor to prevent an explosion.
Blasts caused by a build-up of hydrogen gas took place in three reactors in the aftermath of the earthquake.
“The nitrogen injection is being considered as a precaution,” said Hidehiko Nishiyama, a spokesman for Japan’s Nuclear and Industrial Safety Agency.
‘Water glass’ Plugging the leak from the pit in the No 2 reactor represents a measure of success for engineers at the plant, analysts say.

Fukushima update (6 April)

  • Reactor 1: Damage to the core from cooling problems. Building holed by gas explosion. Radioactive water detected in reactor and basement, and groundwater. Hydrogen gas building up again.
  • Reactor 2: Damage to the core from cooling problems. Building holed by gas blast. Highly radioactive water detected in reactor and adjoining tunnel. Crack identified in containment pit now plugged.
  • Reactor 3: Damage to the core from cooling problems. Building holed by gas blast; containment damage possible. Spent fuel pond partly refilled with water after running low. Radioactive water detected in reactor and basement
  • Reactor 4: Reactor shut down prior to quake. Fires and explosion in spent fuel pond; water level partly restored
  • Reactors 5 & 6: Reactors shut down. Temperature of spent fuel pools now lowered after rising high
It is thought to have been the source of high levels of radiation found in seawater close to the plant.

In order to stem the leak, Tepco (the Tokyo Electric Power Co) injected ”water glass”, or sodium silicate, and another agent into the pit.
Desperate engineers had also used sawdust, newspapers and concrete in recent days to try to stop the escaping water.
The government’s top spokesman said workers could not rule out other leaks at the reactor.
“Right now, just because the leak has stopped, we are not relieved yet,” said Chief Cabinet Secretary Yukio Edano. “We are checking whether the leak has completely stopped, or whether there may be other leaks.”
Meanwhile, engineers are continuing to pump some 11,500 tonnes of low-level radioactive seawater into the sea so the more highly contaminated water can be stored in waste buildings.
Officials said this water would not pose a significant threat to human health, but local fishermen have reacted angrily.
In a letter, the largest fisheries group accused the government of an “utterly outrageous” action that threatened livelihoods.
On Tuesday, elevated levels of radioactive iodine – about twice the legal limit for vegetables – were found in launce (a small fish) caught off Ibaraki prefecture to the south of Fukushima.
The government has promised compensation for the fishing industry and Tepco has already unveiled plans to compensate residents and farmers around the nuclear plant.
Shares in the power giant continued to tumble on Wednesday, hitting a new closing low of 337 yen.
Meanwhile figures from immigration authorities said the number of foreign visitors to Japan had fallen 75% compared with March 2010 in the wake of the earthquake and tsunami that damaged the nuclear plant.
The tourist industry had been hard-hit, with many hotels reporting cancelled bookings, Kyodo news agency reported.
The number of people known to have died in the earthquake and tsunami has now reached 12,494, with another 15,107 still missing, according to police.

Tokyo (CNN) — Radioactive iodine in seawater around the Fukushima Daiichi nuclear power plant dropped sharply even before workers plugged a water leak believed to be from its crippled No. 2 reactor, the plant’s owner said Wednesday night.

Stopping the flow of highly radioactive water into the Pacific Ocean was a key victory for workers who have struggled to keep the earthquake-damaged plant’s reactors from overheating for nearly four weeks. But the Tokyo Electric Power Co. and a top Japanese official warned the fight was far from over.

Concentrations of iodine-131 had been as high as 7.5 million times legal standards in water directly behind the plant after the leak was discovered Saturday. They had dropped to less than 4 percent of that amount in the 24 hours before the leak had been cut off Wednesday morning, according to figures released by Tokyo Electric.

The level remained 280,000 times higher than the legal limit, but those concentrations were dropping sharply as the water flowed out into the Pacific. Levels of longer-lived cesium-137 were down sharply as well but remained 61,000 times the legal standard, according to Tokyo Electric’s water sampling data.

Samples from a monitoring point 20 kilometers (12.5 miles) southeast of the plant found iodine-131 levels down to 1.5 times legal levels, with no reading for cesium.

Japanese authorities said they believe the leaking water was part of the 8 metric tons (2,100 gallons) per hour being pumped in the No. 2 reactor, one of three that suffered core damage after the massive earthquake that struck northern Japan on March 11. The water has been leaking into the basement of the unit’s turbine plant, carrying with it radioactive particles that are the byproduct of nuclear reactors.

Until Wednesday, the fluid was pouring into the ocean from a cracked concrete shaft near the turbine plant’s water intake. Workers managed to use a silica-based polymer dubbed “liquid glass” to seal the breach Wednesday morning, but the Japanese government’s top spokesman on the crisis said government and utility officials had other problems.

“Is it completely stopped? Are there any other areas where (radioactive) water is being released?” said Chief Cabinet Secretary Yukio Edano, the spokesman. “We cannot be optimistic, just because we were able to plug this one.”

Hidehiko Nishiyama of Japan’s Nuclear and Industrial Safety Agency said the now-contained water “may lead to more leakage somewhere else.”

Tokyo Electric began pumping non-flammable nitrogen into the primary containment vessel around reactor No. 1 late Wednesday in what it said was a precautionary measure to counteract a possible buildup of hydrogen.

“The possibility of a hydrogen explosion is extremely low,” the company announced Wednesday night. “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 spectacular blasts that blew the roofs off the No 1 and No. 3 reactor buildings in the days after the March 11 earthquake. But Tokyo Electric said it did not believe an explosion was imminent.

The radioactive cores of units 1-3 were damaged when the tsunami that followed the earthquake flooded the plant, knocking out power to its coolant systems and disabling backup generators needed to restore electricity. Engineers responded by pumping water into the reactors from outside to stave off a feared meltdown, but they are now struggling with what to do with thousands of tons of now-contaminated liquid.

Since Monday night, the plant has been discharging nearly 10,000 tons of less-radioactive water into the ocean, largely to make room in a waste treatment reservoir for the supercharged coolant leaking from the No. 2 reactor.

“Right now they have no systems available to them for processing liquid rad waste, and they’re generating liquid rad waste at the rate of about 400,000 gallons a day,” said Michael Friedlander, a former nuclear power plant operator. “So without any doubt whatsoever, if they don’t put in place some systems to handle this, they are going to have to continue dumping the water into the ocean.”

Tokyo Electric had released about three-quarters of the water — which also came from the subdrains below reactors 5 and 6 — by Wednesday night and had reduced its estimate of how much was being dumped from the treatment facility. But the discharge, which Japanese officials called an emergency measure, drew protests from neighboring South Korea and enraged the country’s fishermen.

Edano said Wednesday that the move was “unavoidable” and would minimize harm to the environment. But he told reporters, “We should have reported (more information) to the people who may be concerned, especially to the neighboring countries.”

“It was a measure to prevent more serious marine contamination, but we needed to explain the reasoning better,” he said.

Members of Japan’s fishery association voiced their ire in a Wednesday morning meeting with Tokyo Electric officials, complaining that they had argued against the measure beforehand and were not told until later that the process would begin. Edano said the Japanese government is considering “provisional compensation” to give a more immediate boost to fishermen, ahead of a more final payment plan that may be established in the future.

Experts have said the releases likely won’t pose any long-term health risks to humans or sea life. It also helps that most of the radiatioactive particles detected are iodine-131, which loses half its radiation every eight days.

The emergency discharge equates to about five swimming pools, compared to “about 300 trillion swimming pools of water” that fill the Pacific Ocean, said Timothy Jorgensen, chairman of the radiation safety committee at Georgetown University Medical Center.

“So hopefully the churning of the ocean and the currents will quickly disperse this so that it gets to very dilute concentrations relatively quickly.”

After a tumultuous first few weeks, utility and government officials have described conditions recently in the plant’s reactors and spent nuclear fuel pools as generally stable. Levels of airborne radiation nearby and further away, meanwhile, steadily have been declining.

Still, the existence of significant amounts of collected radioactive water around the facility suggests that there may be other leaks — and other problems.

Tome, Japan (CNN) — Children run across a playing field in a game of dodgeball, oblivious to the snow that fills the air along with their screams of laughter.
The unadulterated joy is heartening, considering the children and the location. The playing field is a school converted into a shelter in Minamisanriku, one of the worst places hit by the March 11 earthquake and tsunami which cost all the children here their homes, their possessions and — in many cases — family members. Thousands of people are still unaccounted for.

World Vision has created a “child-friendly space,” a program that the organization has replicated around the world, for children to help each other. High school students volunteer to help pick teams for cops and robbers and teach children soccer skills.

The effort goes a long way.

Misato Oyama, 11, lost her grandfather in the tsunami. “I am scared that another big tsunami will come and destroy another part of my city,” she said.

Families who lived along the coast are now scattered among many different shelters, creating more instability for children still dealing with the destruction they have experienced. “For them to regain their routine and their normal life, it’s so important to become stabilized and then recover from their stress and grief,” says Makiba Yamano, a World Vision team leader.

On one morning the gymnasium at Kamaishi elementary school is transformed from the makeshift home it has become for hundreds of people into a venue for a belated graduation day.

“I am overwhelmed I can see my son graduate sixth grade despite every day being a nightmare after friends and relatives have died,” said Shigeko Ogasawara.

Her son Shu was back among friends and laughing, despite his worries about the future.

The principal, Kouko Kato, said she believed that constant tsunami drills helped save the whole class when the actual tsunami alert sounded. “I’m very happy I was able to give 42 certificates to 42 students,” she said.

A worker points to a crack in a concrete pit near Fukushima Daiichi's No 2 reactor, 2 April The concrete pit near Reactor No 2 was cracked by the quake
A leak of highly radioactive water into the Pacific Ocean from Japan’s crippled Fukushima Daiichi nuclear plant has been stopped, its operator reports.

Tepco said it had injected chemical agents to solidify soil near a cracked pit, from where the contaminated water had been seeping out.
Engineers have been struggling to stop leaks since the plant was damaged by the earthquake and tsunami on 11 March.
Japan has asked Russia for the use of a floating radiation treatment plant.
In another development, government sources said that a plan to cover the damaged reactor buildings with special metal sheets could not be carried out until September at the earliest due to high-level radioactivity hampering work at the site.
The official death toll from the 9.0-magnitude earthquake and tsunami stands at more than 12,000 with some 15,000 people still unaccounted for, and more than 161,000 people still living in evacuation centres.
‘Water glass’ Samples of water used to cool one of the plant’s six reactors, No 2, showed 5m times the legal limit of radioactivity, officials said on Tuesday.

The Landysh moored near Vladivostok (archive image from 2004) The Landysh (Suzuran) is used to decommission nuclear submarines

In order to stem the leak, Tepco (the Tokyo Electric Power Co) injected ”water glass”, or sodium silicate, and another agent near a seaside pit where the highly radioactive water had been seeping through.
Desperate engineers had also used sawdust, newspapers and concrete to try to stop the escaping water.
The company still needs to pump some 11,500 tonnes of low-level radioactive seawater into the sea because of a lack of storage space at the plant.
But officials said this water would not pose a significant threat to human health.
Russia’s nuclear agency Rosatom said it was awaiting answers to some questions before granting Japan’s request to lend its vessel the Landysh, known in Japanese as the Suzuran, which is used to decommission Russian nuclear submarines in the far eastern port of Vladivostok.
One of the world’s largest liquid radioactive waste treatment plants, the Landysh treats radioactive liquid with chemicals and stores it in a cement form.
It can process 35 cubic metres of liquid waste a day and 7,000 cubic metres a year.