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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.”

 

Tepco Successfully Removes First Nuclear Fuel Rods at Fukushima – Bloomberg

Tepco Successfully Removes First Nuclear Fuel Rods at Fukushima – Bloomberg.

Tokyo Electric Power Co. (9501) successfully removed the first nuclear fuel rods today from a cooling pool at the wrecked Fukushima nuclear plant, an early milestone in decommissioning the facility amid doubts about whether the rods had been damaged and posed a radiation risk.

The first of the fuel-rod assemblies at the plant’s No. 4 reactor building was transferred from an underwater rack on the fifth floor to a portable cask just before 4 p.m., the utility known as Tepco said in an e-mailed statement.

A member of the media wearing a protective suit and a mask walks in front of a fuel handling machine on the spent fuel pool inside the building housing the No. 4 reactor at Tokyo Electric Power Co.’s (Tepco) Fukushima Dai-ichi nuclear power plant in Okuma, Fukushima Prefecture, Japan on Nov. 7, 2013. Photographer: Tomohiro Ohsumi/Bloomberg

Tepco planned to remove 22 assemblies from the pool, which contains 1,331 spent fuel assemblies and 202 unused assemblies, by the end of tomorrow, the company said. Crews are beginning with the unused assemblies because they are less fragile, spokesman Yusuke Kunikage said by phone.

The operation is the most significant test to date of Tepco’s ability to contain the threat stemming from the worst nuclear disaster since Chernobyl. Were the rods to break or overheat, it could prompt a self-sustained nuclear chain reaction similar to the meltdowns at three Fukushima reactors following the March 2011 earthquake and tsunami.

“Although moving spent fuel into long-term storage is a routine task that Tepco has taken more than 1,200 times over the years, the circumstances at Fukushima Dai-Ichi require special care,” Tepco president Naomi Hirose said in a video message on the company’s website. “The success of the extraction process therefore represents the beginning of a new and important chapter in our work.”

Workers’ Experience

Japan’s Nuclear Regulation Authority assigned an inspector to oversee the removals, in addition to its existing staff at the plant, and is using video monitoring of the removal, the agency said in a statement Friday.

An uncontrolled nuclear reaction due to structural failures or mishandled fuel is highly unlikely because of safeguards and workers’ experience with the procedure, Akira Ono, the Dai-Ichi plant’s chief supervisor, said at a Nov. 7 news conference at the power station.

Removing the rods, bunched in assemblies, will take place from a large shoebox-shaped structure cantilevered atop the reactor building, which was damaged in an explosion after the earthquake and tsunami. The assemblies, each holding about 80 rods, will be moved to a more secure pool on the ground.

Tepco said that it plans to complete the removal of all the fuel in the pool by the end of 2014.

 

We’re In The Most Dangerous Moment Since the Cuban Missile Crisis | Washington’s Blog

We’re In The Most Dangerous Moment Since the Cuban Missile Crisis | Washington’s Blog.

Scientists Warn of Extreme Risk

We’ve long said that the greatest short-term threat to humanity is from the fuel pools at Fukushima.

The Japanese nuclear agency recently green-lighted the removal of the spent fuel rods from Fukushima reactor 4′s spent fuel pool. The operation is scheduled to begin this month.

The head of the U.S. Department of Energy correctly notes:

The success of the cleanup also has global significance. So we all have a direct interest in seeing that the next steps are taken well, efficiently and safely.

If one of the pools collapsed or caught fire, it could have severe adverse impacts not only on Japan … but the rest of the world, including the United States. Indeed, a Senator called it a national security concern for the U.S.:

The radiation caused by the failure of the spent fuel pools in the event of another earthquake could reach the West Coast within days. That absolutely makes the safe containment and protection of this spent fuel a security issue for the United States.

Hiroaki Koide – a nuclear scientist working at the University of Kyoto – says:

I’m worried about whether Tepco can treat all the 1,331 [spent-fuel] assemblies without any problem and how long it will take.

Award-winning scientist David Suzuki says that Fukushima is terrifying, Tepco and the Japanese government are lying through their teeth, and Fukushima is “the most terrifying situation I can imagine”.

Suzuki notes that reactor 4 is so badly damaged that – if there’s another earthquake of 7 or above – the building could come down. And the probability of another earthquake of 7 or above in the next 3 years isover 95%.

Suzuki says that he’s seen a paper that says that if – in fact – the 4th reactor comes down, “it’s bye bye Japan, and everyone on the West Coast of North America should evacuate. Now if that’s not terrifying, I don’t know what is.”

 

 

The Telegraph reports:

The operator of Japan’s crippled Fukushima nuclear power plant … will begin a dry run of the procedure at the No. 4 reactor, which experts have warned carries grave risks.

***

Did you ever play pick up sticks?” asked a foreign nuclear expert who has been monitoring Tepco’s efforts to regain control of the plant. “You had 50 sticks, you heaved them into the air and than had to take one off the pile at a time.

“If the pile collapsed when you were picking up a stick, you lost,” he said. “There are 1,534 pick-up sticks in a jumble in top of an unsteady reactor 4. What do you think can happen?

I do not know anyone who is confident that this can be done since it has never been tried.”

ABC notes:

One slip-up in the latest step to decommission Japan’s crippled Fukushima nuclear plant could trigger a “monumental” chain reaction, experts warn.

***

Experts around the world have warned … that the fuel pool is in a precarious state – vulnerable to collapsing in another big earthquake.

Yale University professor Charles Perrow wrote about the number 4 fuel pool this year in the Bulletin of Atomic Scientists.

“This has me very scared,” he told the ABC.

Tokyo would have to be evacuated because [the] caesium and other poisons that are there will spread very rapidly.

Perrow also argues:

Conditions in the unit 4 pool, 100 feet from the ground, are perilous, and if any two of the rods touch it could cause a nuclear reaction that would be uncontrollable. The radiation emitted from all these rods, if they are not continually cool and kept separate,would require the evacuation of surrounding areas including Tokyo. Because of the radiation at the site the 6,375 rods in the common storage pool could not be continuously cooled; they would fission and all of humanity will be threatened, for thousands of years.

Former Japanese ambassador Akio Matsumura warns that – if the operation isn’t done right – this could one day be considered the start of “the ultimate catastrophe of the world and planet”:

(He also argues that removing the fuel rods will take “decades rather than months.)

Nuclear expert Arnie Gundersen and physician Helen Caldicott have both said that people should evacuate the Northern Hemisphere if one of the Fukushima fuel pools collapses. Gundersen said:

Move south of the equator if that ever happened, I think that’s probably the lesson there.

Harvey Wasserman wrote two months ago:

We are now within two months of what may be humankind’s most dangerous moment since the Cuban Missile Crisis.

***

Should the attempt fail, the rods could be exposed to air and catch fire, releasing horrific quantities of radiation into the atmosphere. The pool could come crashing to the ground, dumping the rods together into a pile that could fission and possibly explode. The resulting radioactive cloud would threaten the health and safety of all us.

***

A new fuel fire at Unit 4 would pour out a continuous stream of lethal radioactive poisons for centuries.

Former Ambassador Mitsuhei Murata says full-scale releases from Fukushima “woulddestroy the world environment and our civilization. This is not rocket science, nor does it connect to the pugilistic debate over nuclear power plants. This is an issue of human survival.”

Even Japan’s Top Nuclear Regulator Says that The Operation Carries a “Very Large Risk Potential”

Even the head of Japan’s nuclear agency is worried. USA Today notes:

Nuclear regulatory chairman Shunichi Tanaka, however, warned that removing the fuel rods from Unit 4 would be difficult because of the risk posed by debris that fell into the pool during the explosions.

It’s a totally different operation than removing normal fuel rods from a spent fuel pool,” Tanaka said at a regular news conference. “They need to be handled extremely carefully and closely monitored. You should never rush or force them out, or they may break.”

He said it would be a disaster if fuel rods are pulled forcibly and are damaged or break open when dropped from the pool, located about 30 meters (100 feet) above ground, releasing highly radioactive material. “I’m much more worried about this than contaminated water,” Tanaka said

The same top Japanese nuclear official said:

The process involves a very large risk potential.

BBC reports:

A task of extraordinary delicacy and danger is about to begin at Japan’s Fukushima nuclear power station.

***

One senior official told me: “It’s going to be very difficult but it has to happen.”

Why It’s Such a Difficult Operation

CNN notes that debris in the fuel pool might interfere with operations:

South China Morning Post notes:

Nothing remotely similar has been attempted before and … it is feared that any error of judgment could lead to a massive release of radiation into the atmosphere.

***

A spokesman for Tepco … admitted, however, that it was not clear whether any of the rods were damaged or if debris in the pool would complicate the recovery effort.

The Wall Street journal notes:

Among the risks [Hiromitsu Ino, professor emeritus of nuclear engineering at the University of Tokyo] and other experts cite is the possibility that a container being used to move the units falls and breaks apart, exposing the fuel to the air.

Similarly,  Edwin Lyman – a nuclear expert and the chief scientist for the Union of Concerned Scientistsnotes:

The biggest risk with Unit 4 pool unloading is that a spent fuel cask might drop and damage the pool, causing a leak that could expose some fuel and cause overheating.

Professor Richard Broinowski – former Australian Ambassador to Vietnam, Republic of Korea, Mexico, the Central American Republics and Cuba – and author of numerous books on nuclear policy and Fukushima, says some of the fuel rods are probably fused.

Murray E. Jennex, Ph.D., P.E. (Professional Engineer), Professor of MIS, San Diego State University,notes:

The rods in the spent fuel pool may have melted …. I consider it more likely that these rods were breached during the explosions associated with the event and their contents may be in contact with the ground water, probably due to all the seawater that was sprayed on the plant.

Fuel rod expert Arnie Gundersen – a nuclear engineer and former senior manager of a nuclear power company which manufactured nuclear fuel rods – recently explained the biggest problem with the fuel rods (at 15:45):

I think they’re belittling the complexity of the task. If you think of a nuclear fuel rack as a pack of cigarettes, if you pull a cigarette straight up it will come out — but these racks have been distorted. Now when they go to pull the cigarette straight out, it’s going to likely break and release radioactive cesium and other gases, xenon and krypton, into the air. I suspect come November, December, January we’re going to hear that the building’s been evacuated, they’ve broke a fuel rod, the fuel rod is off-gassing.

***

I suspect we’ll have more airborne releases as they try to pull the fuel out. If they pull too hard, they’ll snap the fuel. I think the racks have been distorted, the fuel has overheated — the pool boiled – and the net effect is that it’s likely some of the fuel will be stuck in there for a long, long time.

In another interview, Gundersen provides additional details (at 31:00):

The racks are distorted from the earthquake — oh, by the way, the roof has fallen in, which further distorted the racks.

The net effect is they’ve got the bundles of fuel, the cigarettes in these racks, and as they pull them out, they’re likely to snap a few. When you snap a nuclear fuel rod, that releases radioactivity again, so my guess is, it’s things like krypton-85, which is a gas, cesium will also be released, strontium will be released. They’ll probably have to evacuate the building for a couple of days. They’ll take that radioactive gas and they’ll send it up the stack, up into the air, because xenon can’t be scrubbed, it can’t be cleaned, so they’ll send that radioactive xenon up into the air and purge the building of all the radioactive gases and then go back in and try again.

It’s likely that that problem will exist on more than one bundle. So over the next year or two, it wouldn’t surprise me that either they don’t remove all the fuel because they don’t want to pull too hard, or if they do pull to hard, they’re likely to damage the fuel and cause a radiation leak inside the building. So that’s problem #2 in this process, getting the fuel out of Unit 4 is a top priority I have, but it’s not going to be easy. Tokyo Electric is portraying this as easy. In a normal nuclear reactor, all of this is done with computers. Everything gets pulled perfectly vertically. Well nothing is vertical anymore, the fuel racks are distorted, it’s all going to have to be done manually. The net effect is it’s a really difficult job. It wouldn’t surprise me if they snapped some of the fuel and they can’t remove it.

The Japan Times writes:

The consequences could be far more severe than any nuclear accident the world has ever seen. If a fuel rod is dropped, breaks or becomes entangledwhile being removed, possible worst case scenarios include a big explosion, a meltdown in the pool, or a large fire. Any of these situations could lead to massive releases of deadly radionuclides into the atmosphere, putting much of Japan — including Tokyo and Yokohama — and even neighboring countries at serious risk.

Reuters notes:

Experts question whether it will be able to pull off the removal of all the assemblies successfully.

***

No one knows how bad it can get, but independent consultants Mycle Schneider and Antony Froggatt said recently in their World Nuclear Industry Status Report 2013: “Full release from the Unit-4 spent fuel pool, without any containment or control, could cause by far the most serious radiological disaster to date.”

***

Nonetheless, Tepco inspires little confidence. Sharply criticized for failing to protect the Fukushima plant against natural disasters, its handling of the crisis since then has also been lambasted.

***

“There is a risk of an inadvertent criticality if the bundles are distorted and get too close to each other,” Gundersen said.

***

The rods are also vulnerable to fire should they be exposed to air, Gundersen said. [The pools have already boiled due to exposure to air.]

***

[Here is a visual tour of Fukushima’s fuel pools, along with graphics of how the rods will be removed.]

Tepco confirmed the Reactor No. 4 fuel pool contains debris during an investigation into the chamber earlier this month.

Removing the rods from the pool is a delicate task normally assisted by computers, according to Toshio Kimura, a former Tepco technician, who worked at Fukushima Daiichi for 11 years.

“Previously it was a computer-controlled process that memorized the exact locations of the rods down to the millimeter and now they don’t have that. It has to be done manually so there is a high risk that they will drop and break one of the fuel rods,” Kimura said.

***

Corrosion from the salt water will have also weakened the building and equipment, he said.

ABC Radio Australia quotes an expert on the situation (at 1:30):

Richard Tanter, expert on nuclear power issues and professor of international relations at the University of Melbourne:

***

Reactor Unit 4, the one which has a very large amount of stored fuel in its fuel storage pool, that is sinkingAccording to former prime Minister Kan Naoto, that has sunk some 31 inches in places and it’s not uneven.

And Chris Harris – a, former licensed Senior Reactor Operator and engineer – notes that it doesn’t help that a lot of the rods are in very fragile condition:

Although there are a lot of spent fuel assemblies in there which could achieve criticality — there are also 200 new fuel assemblies which have equivalent to a full tank of gas, let’s call it that. Those are the ones most likely to go critical first.

***

Some pictures that were released recently show that a lot of fuel is damaged, so when they go ahead and put the grapple on it, and they pull it up, it’s going to fall apart. The boreflex has been eaten away; it doesn’t take saltwater very good.

Nuclear engineers say that the fuel pool is “distorted”, material was blown up into air and came down inside, damaging the fuel, the roof fell in, distorting things inside.

Indeed, Fukushima documents discuss “fuel that is severely damaged” inside cooling pool, and show illustrations of “deformed or leaking fuels”.

The Urgent Need: Replace Tepco

Tepco is severely downplaying the risks involved in removing fuel rods. For example, Tepco’s head of the Fukushima plant, Akira Ono, says:

We have removed spent fuels many times. Therefore, we don’t think we are going to be doing anything that is very dangerous.

That is idiotic given that (as shown above) this is anything but a normal fuel removal operation.

Tepco is incompetent and corrupt, and has been in cover-up mode since day one. As such, it is the lastcompany which should be in charge of the clean-up.

Top scientists and government officials say that Tepco should be removed from all efforts to stabilize Fukushima. They say that an international team of the smartest engineers and scientists should instead handle this difficult mission.

Bloomberg notes:

Prime Minister Shinzo Abe is being told by his own party that Japan’s response is failing.Plant operator [Tepco] alone isn’t up to the task of managing the cleanup and decommissioning of the atomic station in Fukushima. That’s the view of Tadamori Oshima, head of a task force in charge of Fukushima’s recovery and former vice president of Abe’s Liberal Democratic Party.

***

[There’s] a growing recognition that the government needs to take charge at the Fukushima station…. “If we allow the situation to continue, it’ll never be resolved” [said Sumio Mabuchi, a government point man on crisis in 2011].

Because the U.S. controls Japanese nuclear policy, Americans should demand of our political representatives that they pressure Japan to kick Tepco off the job … and let an international team of scientists and engineers take over.

Postscript: As challenging as removing the fuel rods from the pool at unit 4 will be, it will be even harder at units 1 through 3. Specifically, it’s too radioactive for Tepco to even get a look at what’s going on in those 3 reactor pools, and they have no idea how to do it. Indeed, the technology does not even exist to approach those reactors, as the high radiation levels quickly destroy even robots.

Nuclear fuel rod expert Gundersen says the pool at unit 3 is in much worse shape than at 4:

Unit 3 is worse [than No. 4]. Mechanically its rubble, the pool is rubble. It’s got less fuel in it [than unit 4, but] structurally the pool has been dramatically weakened. And, god nobody has even gotten near it yet.

Tepco’s not up to it … we need a focused, well-funded international effort to fix this mess

 

Fukushima-Fuel Rod Removal Starts, Risk Spikes

 

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