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Fukushima’s crippled reactors: the risky plan to move fuel rods – World – CBC News

Fukushima’s crippled reactors: the risky plan to move fuel rods – World – CBC News.

TEPCO workers trying to stabilize Japan's tsunami-crippled nuclear reactors at the Fukushima Daiichi power plant are examined for excessive radiation exposure after their shifts.TEPCO workers trying to stabilize Japan’s tsunami-crippled nuclear reactors at the Fukushima Daiichi power plant are examined for excessive radiation exposure after their shifts. (Tomohiro Ohsumi / Associated Press)

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The thousands of people who punch in every day at what is arguably the world’s most dangerous workplace are accustomed to facing risks.

 

But now workers at the crippled Fukushima Daiichi nuclear plant have embarked on their most precarious operation since the March 11, 2011, earthquake and tsunami triggered meltdowns and explosions at the facility.

 

On Monday, select crews from Tokyo Electric Power Company began  removing hundreds of highly radioactive spent fuel rods from a cooling pool inside a rickety reactor building, a job that is unprecedented in scale, and where one wrong move could have disastrous consequences.

Fuel rod quick facts

Workers at Fukushima Daiichi plan to remove more than 3,100 fuel rod assemblies from four reactor buildings.

Tokyo Electric Power Company officials say 80 of those assemblies are cracked — 70 in the reactor one building. They say holes and cracks in the damaged assemblies could cause radioactive particles to leak out.

Six teams of six workers will operate the crane to move the assemblies to the special containers. Each team can only work for two hours a day — they rotate to keep the operation moving, to minimize radiation exposure.

The amount of radioactive cesium-137 in the pool holding the fuel rod assemblies is said to be the equivalent of roughly 14,000 Hiroshima-sized atomic bombs.

 

 

“It’s a totally different operation than removing normal fuel rods from a spent fuel pool,” Shunichi Tanaka, the chairman of Japan’s Nuclear Regulation Authority, said recently.

 

“They need to be handled extremely carefully and closely monitored. You should never rush or force them out, or they may break. I’m much more worried about this than I am about contaminated water.”

 

TEPCO’s checkered track record

 

But given that TEPCO has not exactly won over the Japanese public with its handling of the catastrophe, and that the amount of radioactive cesium-137 in the pool is said to be the equivalent of roughly 14,000 Hiroshima-sized atomic bombs, this next step is turning into a crucial test for the beleaguered utility as much as it is an engineering challenge.

 

Few in Japan or abroad seem convinced that TEPCO can pull this off, given the company’s checkered track record.

 

This is the same utility, they point out, that used false inspection reports years ago to cover up faults at Fukushima Daiichi; that dismissed warnings in 2008 that a monster tsunami could engulf the plant; that waited weeks to admit meltdowns even happened in March 2011, and that waited many months to acknowledge radioactive water is leaking into the Pacific Ocean.

India-nuclear-protestAnti-nuclear activists around the world, like those here in Mubai, India, in October, have stepped up their campaigns following the meltdown of the Fukushima reactors two years ago. (Rafiq Maqbool / Associated Press)

 

It has also held back key information and stumbled from problem to problem over the past two-and-a-half years.

 

In fact, TEPCO has performed so poorly that a task force for Japan’s ruling Liberal Democratic Party is recommending it be split up so that the job of decommissioning the wrecked plant would be separated from the utility’s power-generating role.

 

Managing risks

 

The fuel rods to be removed over the next 12 months or so are mostly in reactor four, which was offline when Fukushima Daiichi was shaken by powerful tremors and swamped by towering waves.

 

In the subsequent hydrogen explosions and fires, debris rained down on the large pool that holds 1,533 fuel rod assemblies —1,331 used and 202 unused. Another roughly 1,500 assemblies in the three other reactors are to be removed as well.

 

Workers spent months shoring up the structure and the pool, fearing another strong quake could trigger a catastrophe.

 

TEPCO spokesperson Tatsuhiro Yamagishi told CBC News that along with cesium-137 and cesium-134, the radioactive isotopes contained in the fuel include strontium-90, radium-226, uranium-235, and plutonium-239, which has a half-life of approximately 24,000 years.

 

Yamagishi admits engineers don’t know exactly how many assemblies have been damaged. The current estimate is that 80 have cracks.

 

“We are managing different types of risks,” he said. “We are evaluating each case right now.”

 

John Froats, an associate professor and nuclear engineer in residence at the University of Ontario Institute of Technology, says those risks can probably be dealt with if handled carefully.

hi-fukushima-google-852 

 

“The Fukushima Daiichi plant evolution is no doubt complicated by the plant damage and debris,” he said. “These complications can be managed by careful inspection to understand the state of systems and equipment and the fuel, and then by careful planning of the step-by-step tasks that need to be achieved.”

 

TEPCO workers have already removed a good amount of debris, checked some fuel rod assemblies to make sure they weren’t corroded by the seawater that was used to cool the pool in the early days of the crisis, and stabilized the building.

 

 

They’ve also successfully removed two unused rod assemblies. This week they began using the specially constructed crane to extract the fuel units one-by-one, keeping them underwater as they move them into specially-designed containers and then to another location on site.

 

In a corporate video on the TEPCO website, a deep-voiced narrator cheerfully runs through a simplified version of the process.

 

“Moving the spent fuel out of the damaged reactor building and into safe, permanent storage lays the groundwork for moving forward with cleanup and remediation of the damaged reactor building,” the video says.

 

In the video, TEPCO also calls the removal of the fuel rod assemblies from the reactor four building “a milestone” in the recovery of Fukushima Daiichi.

 

The world is watching

 

Certainly, it’s a key part of the decades-long decommissioning process now underway, and perhaps key to the company’s survival.

 

But while utility managers have no choice but to show they’re up to the task, the reality is they’re tackling a challenge none in their industry has faced before, and they’ll be carrying out the work knowing people around the world will be watching with critical eyes.

Fukushima-craneTEPCO workers gather earlier this month near the giant crane that began on Monday lifting stored fuel rod assemblies from Daiichi reactor four. (Kimimasa Mayama / Associated Press)

 

Among the critics is Mitsuhiko Tanaka, a science journalist and engineer who helped build part of reactor four at Fukushima Daiichi (and who later admitted to helping cover up a manufacturing flaw with the unit).

 

As he sees it, “TEPCO is a selling-electricity company, not an engineering company.

 

“It is quite apparent that TEPCO doesn’t have enough ability to cope with the problems in progress now. That’s why [it] has made a lot of mistakes.”

 

Tanaka, who calls the current state of the nuclear plant “hopeless,” says that while the utility has plenty of experience in normal fuel removal work, this job is different because of the possibility that some of the rod assemblies have been damaged.

 

And although TEPCO spokespersons insist their inspections and those by outside experts confirm the reinforcement of the reactor building has made it seismically sound, Tanaka maintains the structure is still vulnerable.

 

“I think it is very dangerous,” he says. “Furthermore, this very difficult work is going to be done in an earthquake-prone country.”

TEPCO was given permission in late summer to take on the removal of the fuel rods. But just before the operation begain U.S. Energy Secretary Ernest Moniz visited the facility to offer American help.

 

“The success of the cleanup also has global significance,” Moniz said. “We all have a direct interest in seeing that the next steps are taken well, efficiently and safely.”

 

Fukushima-Fuel Rod Removal Starts, Risk Spikes

 

TEPCO Admits To Finding Radioactive Cesium 1Km Off Coast Of Fukushima | Zero Hedge

TEPCO Admits To Finding Radioactive Cesium 1Km Off Coast Of Fukushima | Zero Hedge. (source)

The dismal news keeps coming for the Fukushima nuclear power facility. According to NHK World, TEPCO is admitting to detecting radioactive cesium about one kilometer off shore. While the level is low, it is the secoond time radioactive substances have been found that far offshore and it is believed to be from wastewater leaking out with the groundwater. The company, reassuringly, says the leak poses no environmental risk… As if that was not enough, Bloomberg reports TEPCO also found high levels of radiation in the drainage ditches and wells at the site. Of course, this will likely be met with cries of delight by Abe who will “need to build a bigger wall” to contain the leaks and thus create a Keynesian utopia from the ‘broken nuclear plant fallacy’ that is ongoing.

Via NHK World,

Tokyo Electric Power Company says a very small amount of radioactive cesium has been detected about one kilometer off the damaged Fukushima Daiichi nuclear plant it operates.

TEPCO has been analyzing seawater taken at 5 locations outside the plant’s harbor. This is to monitor the spread of radioactive substances in wastewater that’s believed to be seeping out with groundwater.

A sample taken last Friday about one kilometer offshore was found to contain 1.6 becquerels of cesium-137 per liter.

The level is far below the 90 becquerels-per-liter limit for releasing cesium-137 into the sea. But it is the second time the substance has been detected at this location since monitoring began in August. The previous finding was on October 8th.

TEPCO says it does not know why cesium has been found at that specific spot. But the company says it poses no environmental risk as the level is near the minimum detection threshold. It adds that hardly any cesium is being found elsewhere in the sea outside of the port.

Via Bloomberg,

Co. found 59,000 Bq/L of beta radiation levels from water taken yesterday at B-2 drainage ditch at Fukushima Dai-Ichi plant, higher than previous record of 34,000 Bq/L in Oct. 17 sample, according to an e-mailed statement from the utility.

Co. detects 350,000 Bq/L of tritium radiation at monitoring well “No. 1-12” near turbine buildings, according to a separate statement

First time to take sample from monitoring well “No.  1-12, Co. found record 790,000 Bq/L of tritium radiation    near H4 storage tank area on Oct. 17

We just can’t wait to see the Olympic sailing events with boats whose hulls are lead-shielded…

 

Fukushima overwhelmed with radioactive water – Asia-Pacific – Al Jazeera English

Fukushima overwhelmed with radioactive water – Asia-Pacific – Al Jazeera English. (source)

Highly radioactive water overflowed barriers into Japan’s Fukushima Daiichi nuclear power station after its operator Tepco underestimated how much rain would fall and failed to pump it out quickly enough.

Tepco has been battling to contain radioactive water at the nuclear complex, which suffered meltdowns and hydrogen explosions following a devastating earthquake and tsunami in March 2011.

Dealing with hundreds of tonnes of groundwater flowing through the wrecked nuclear station daily is a constant problem for the utility and for the government, casting doubt on the promises of Japan’s prime minister, Shinzo Abe, that the Fukushima water “situation is under control”.

After heavy rain on Sunday, water with high levels of radioactive strontium overflowed containment areas built around
some 1,000 tanks storing tonnes of radioactive water at the plant, Tepco said.

The radioactive water is a by-product of an improvised cooling system designed to keep the wrecked reactors under control in case of further disaster.

Tepco said it had planned to pump out the accumulating rainwater into empty tanks, check it for radioactivity, and if
it was uncontaminated, release into the sea. But the company was overwhelmed by the amount of rainwater.

“Our pumps could not keep up with the rainwater. As a result, it flowed over some containment areas,” said Tepco
spokesman Yoshikazu Nagai.

The company had planned for 30mm to 40mm of rainfall on Sunday, but by late afternoon the rainfall already stood at about 100mm, he said.

The ongoing crisis at the Fukushima Daiichi plant, 220km north of Tokyo, highlights the immensity of the task of containing and controlling radioactive water and eventually decommissioning the plant, processes that are expected to take decades.

Tepco is seeking permission to restart its only remaining viable power station – Kashiwazaki Kariwa, the world’s largest nuclear power facility, to cut high fuel costs and restore its finances.

 

Fukushima: Japan promises swift action on nuclear cleanup | Environment | theguardian.com

Fukushima: Japan promises swift action on nuclear cleanup | Environment | theguardian.com.

 

Fukushima apocalypse: Years of ‘duct tape fixes’ could result in ‘millions of deaths’  |  Peak Oil News and Message Boards

Fukushima apocalypse: Years of ‘duct tape fixes’ could result in ‘millions of deaths’  |  Peak Oil News and Message Boards.

 

“Tepco Has Lost Control” – What Is Really Happening At Fukushima In Four Charts | Zero Hedge

“Tepco Has Lost Control” – What Is Really Happening At Fukushima In Four Charts | Zero Hedge.

 

3. Fukushima Nuclear Disaster Worse than Anticipated – The Top 25 Most Censored Stories of 2012

3. Fukushima Nuclear Disaster Worse than Anticipated – The Top 25 Most Censored Stories of 2012.

More steam rising from Fukushima reactor – Asia-Pacific – Al Jazeera English

More steam rising from Fukushima reactor – Asia-Pacific – Al Jazeera English.

Steam Rising Again From Fukushima Reactor | Zero Hedge

Steam Rising Again From Fukushima Reactor | Zero Hedge.

 

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