Japan's Fukushima nuclear plant leaks: What you need to know
Earlier this week, Tokyo Electric Power Co. revealed that approximately 300 tons of highly radioactive water had escaped from the temporary storage tanks hastily built in the aftermath of the massive earthquake and tsunami in March 2011.
According to the cash-strapped utility company, the leaking water tanks were made using a rubber seam that was intended to last only five years.
TEPCO says it will build additional storage tanks with welded seams that are more watertight, but that it will continue to use the rubber-seamed tanks despite at least five of them having leaked since last year.
News of the latest leak this week comes after TEPCO admitted earlier in the summer that it is struggling to stop radioactive groundwater -- which picks up trace amounts of contamination when it flows through the damaged reactor buildings -- from seeping into the ocean.
TEPCO officials estimate that approximately 300 tons of toxic water is rushing into the Pacific Ocean daily, enough to fill an Olympic-sized swimming pool every eight days.
The breach prompted the Japanese government to take a more direct role in the clean-up effort, marking a significant escalation in pressure for TEPCO to take a more aggressive approach in what some critics say appears to be a losing battle.
Here are some answers to some basic questions about the crippled Fukushima Dai-ichi nuclear power plant.
#1. What can be done to plug the leak and stop more contaminated water from seeping into the ocean?
According to a full status report released last year, TEPCO has already put in place a number of measures in an attempt to control the radioactive water. The ill-fated utility company built a groundwater bypass system which tried to reroute water flowing down from the mountain side of the plant, before it seeped into the basement of the reactor buildings. The solution did little to siphon off the water.
In its latest attempt, the Japanese government will be building an underground frozen barrier. The plan reportedly involves sinking pipes into the ground in an attempt to freeze the soil.
While the proposed strategy has been described by some Japanese officials as a high-tech forward thinking plan, some experts believe the idea is just another Band-Aid solution
"It's not a solution that has any permanence," Arnie Gundersen, a nuclear engineer with Fairewinds Energy Education, told CTVNews.ca.
"The problem with freezing the soil is that as soon as you get an earthquake, you lose power and then your ice turns to mush and you're stuck."
Gundersen, who has visited the Fukushima power plant in the past, said a better solution would be to dig a two-metre wide trench down to bedrock level and fill it with a material called zeolite: a volcanic material that comes from Mother Nature.
"It's incredibly good at filtering radioactive isotopes. So whatever is inside the fence will stay inside and whatever is outside the fence would be clean," said Gundersen, who estimates the price tag for such a project would be around $10 billion.
#2. What is perpetuating the crisis?
According to some experts, the clean-up effort at the damaged Fukushima Dai-ichi nuclear power plant has been hampered by a reluctant government and a "bankrupt firm."
"TEPCO has an enormous degree of influence within the Japanese government," Andrew DeWit, a professor of public finance at Rikkyo University in Tokyo, told CTVNews.ca. "Basically, you've got a bankrupt firm that has been left to take care of the Fukushima Dai-ichi clean-up and decommissioning pretty much on its own."
Dewit added that although TEPCO became a nationalized firm last year, the utility company does not directly answer to any regulatory bodies, including the country's nuclear watchdog, which he says hasn't been exercising its full regulatory and investigatory authority.
"You've got a couple of agencies up there and nobody is really solely in charge of this and solely responsible," he said. "Considering the gravity of the situation, you've got a completely untenable sort of arrangement."
DeWit said the "only solution" would be for Japan's popular prime minister, Shinzo Abe, who he says is the most equipped and powerful actor in the country, to strong arm TEPCO and tell it what to do.
DeWit, however, is doubtful that will happen given Abe's political interests.
"His big deal is getting the constitution rewritten and repositioning the country in terms of geopolitics," said DeWit. "So his interests in this issue would appear to be quite marginal."
Experts also believe that given Abe's interest in restarting Japan's nuclear energy program in an attempt to reawaken the country's languishing economy, there is very little political incentive for him to pour money into the clean-up effort.
"The problem is the Japanese government hasn't been fighting this battle. They've been letting Tokyo Electric try fight using their earnings," said Gundersen, who said the entire clean-up effort will cost at least half a trillion U.S. dollars.
"The Japanese government under Abe doesn't want to admit (to the cost) because they are trying to restart a nuclear energy program and the last thing they need to do is tell the Japanese people that ‘oh by the way, you're on the hook for another half trillion dollars,'" he said.
According to Gundersen, many of the recent reported problems at the crippled nuclear power plant were predicted more than two years ago by experts at the outset of the disaster.
"At the root of the problem is not that it wasn't foreseeable, it's that the Japanese government didn't have the courage to step up two years ago and fight this as if it was a war," Gundersen said, adding that the government has been treating the clean-up effort as budgetary exercise.
"You don't fight a war on a budget and the Japanese government has allowed Tokyo Electric to fight this as a budget."
#3. What are the 'unknowns'?
Following the 2011 disaster, TEPCO has faced a growing catalogue of problems, including several leaks of radioactive water which has been accumulating as a result of continual water injections to cool the damaged reactors.
Although no one can confirm where the melted fuel cores are located, some experts believe some of the radioactive material from the damaged core has moved into the earth. The recent spike in radiation levels in the water may therefore be coming from groundwater coming into contact with the melted cores.
Earlier this month, TEPCO said that radiation levels in its groundwater observation hole located on the east side of the complex had reached 310 becquerels per litre for cesium-134 and 650 becquerels per litre for cesium-137.
According to the World Health Organization, drinking water at 300 becquerels per litre would be approximately equal to one year's exposure to natural background radiation, or 10 to 15 chest X-rays.
#4. What are the 'knowns'?
In an effort to cool the damaged reactors, TEPCO has been pumping an enormous amount of water in and out of the complex. But that water is contaminated with radioactive material and has been rushing back out into the ocean due to leaks in its storage tanks.
In an attempt to recover the contaminated water from the leaking tanks, TEPCO is betting on a state-of-the-art filtration system to clean the radioactive material from the accumulated water before discharging it back out into the ocean. But according to an April report from the IAEA, the filtering system "has not accomplished the expected results" and is still a work-in-progress.
In addition to the leaking toxic water, experts point to another culprit behind why high levels of radiation have been found in the ocean: the natural movement of groundwater from the mountains that streams into the basements of the damaged reactors each day. Keeping that water from flowing into the ocean is headache TEPCO has been struggling to deal with. According to a report from the UN's International Atomic Energy Agency, the "accumulation of enormous amounts of liquids due to the continuous intrusion of underground water into the reactor and turbine buildings is influencing the stability of the situation."
#5. What are the potential risks to people worldwide?
The question of health risks is a murky one and the answer varies according to who you ask.
According to Gundersen, who says this is the last year he's eating west coast fish, the deluge of toxic water into the Pacific has already contaminated the ocean.
He says that halfway across the Pacific, scientists are measuring cesium levels that are 10 times higher than normal.
Gundersen said naturally occurring cesium levels are approximately 1 becquerel per cubic metre. He said the current levels are 10 becquerels per cubic metre.
"Of course, scientists will say that is still a low level but it's such a big ocean and there are so many organisms that rely on it… so it's a concern and it's a concern that's getting worse because the plant continues to leak."
But according to Dr. Bonnie Henry, the director of public health emergency management for the B.C. Centres for Disease Control, the size of the ocean creates a dilution effect, protecting humans not immediately in the plant's area from any health risks.
"The dilution factor and time factor means that there are no concerns of health risks in B.C.," said Dr. Henry.
She added that the Pacific salmon that's commonly eaten in Canada are not exposed to the contaminated water from the crippled Dai-ichi plant because its migratory pattern doesn't include the waters near Japan.
"The Pacific salmon that we have don't generally go that far into the waters around Japan. They are mostly around the Alaska Gulf and into the central part of the Pacific."
#6. What are the risks to people in the immediate area?
According to a report from the WHO that was published earlier this year, researchers concluded that the radiation released in the immediate wake of the accident could cause a "somewhat elevated" lifetime risk of cancer among the local population.
Outside the immediate area of the plant, however, even in locations within Fukushima prefecture, the report found that there were no observable increases in cancer above the "natural variation in baseline rates."
Some individuals, however, have claimed their health is deteriorating as a result from exposure to radiation while helping with relief operations in 2011.
Lt. Steve Simmons told the Japan Daily Press that he has lost 30 per cent of his muscle mass and has lost the ability to take care of himself.
"We've never had any kind of health issues until he was exposed to radiation from Fukushima," Simmons' wife, Summer, said. "The muscle weakness has progressed to the point where he needs 24-hour care."
Despite what Simmons says, however, medical professionals, including those working for the U.S. Department of Defense, have not been able to provide a diagnosis, reports the Japan Daily Press.
In the latest leak, radiation levels were measured from about 50 centimetres above the toxic puddle was approximately 100 millisierverts per hour -- the maximum cumulative exposure allowed for plant workers over five years.
#7. What is TEPCO planning in the near future?
In November, TEPCO is planning to remove 400 tons of highly irradiated spent fuel at the plant's damaged Reactor No. 4.
The operation, according to Gundersen, is fraught with risks, including the possibility of releasing a large amount of radiation if a fuel assembly breaks or gets too close to a neighbouring bundle.
"The problem with Dai-ichi is that the racks (that hold the spent fuel) are damaged. So TEPCO is not going to be able to easily pull the fuel from them," he said, adding that the rubble left over from the earthquake and tsunami in 2011 and the murky water means plant operators will not be able to use a computerized arm.
"The Japanese seem to think they can pull these out easily but in my experience, it's not going to be an easy process," Gundersen said.
It is unclear how bad the situation could get, but according to independent consultants Mycle Schneider and Antony Froggatt in the recently published World Nuclear Industry Status Report, "Full release from Unit-4 spent fuel pool, without any containment or control, could cause by far the most serious radiological disaster to date."
With files from The Associated Press
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