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Saturday, June 23, 2012

TEPCO to speed up removal of spent fuel rods at Fukushima reactor No. 4 by 12 months

Japan to speed up Fukushima nuclear plant cleanup

by Kiyoshi Takenaka and Yoko Kubota, Japan Today, June 22, 2012
Workers at the crippled Fukushima Daiichi nuclear plant will begin removing fuel rods from a damaged reactors a year ahead of schedule, a government minister said Thursday, a move to address concerns about the risk of a new quake that could cause a further accident and scatter more radioactive debris.
“We would like to start taking out undamaged fuel this year. Preparation is now under way,” Japan’s nuclear crisis minister, Goshi Hosono, told Reuters in an interview.
“Doing it quickly is important. But we also have to make sure those workers out there, who are struggling under harsh conditions, will not be endangered by trying to move things fast.”
Tokyo Electric Power Co (TEPCO), operator of the plant, had said in April it aimed to begin removing the fuel rods from the No. 4 reactor at the end of next year.
That would have left large quantities of radioactive fuel rods outside the protection of strong containment vessels for two and a half years after the accident.
Experts say the fuel rods, now covered only by water and a white plastic tarp, could present a risk of a knock-on accident if the reactor building collapsed or the water supply used to keep the rods cool were disrupted by another earthquake.
Some 1,535 fuel assemblies—enough uranium fuel rods to power three reactors—are being stored in a pool atop the mangled No. 4 reactor building. The reactor, which was shut down for maintenance at the time of the March 2011 earthquake and tsunami, was badly damaged by a series of powerful explosions that followed the disaster as power was cut off to the plant.
Hosono said last month during a visit to the Fukushima plant that he expected workers to begin removing fuel from the No. 4 reactor’s storage pool next year.
Work began in April to raise what amounts to a giant tent over the building to keep radioactive dust from scattering during the transport of the fuel rods.
TEPCO says its analysis shows the No.4 reactor building would hold up in a strong earthquake. But Japanese safety regulators ordered TEPCO to recheck its findings last month after measurements showed one of the walls of the reactor building was buckling out by about 3 centimeters.
The removed uranium fuel rods will be placed in another storage pool at the Fukushima plant, officials have said.
Hosono also said Tokyo was considering setting up a training facility for nuclear workers, including engineers, to secure specialists for the long process of decommissioning the Fukushima plant and cleaning up radioactive debris.
“It will be 10 years, 20 years, probably even more before decommissioning is complete,” Hosono said. “The task will not be sustainable unless we train the next generation of talent, and the generation after that.”
He added: “The government is looking into establishing a place for bringing up such talent. When it comes to a location, Fukushima would make an excellent training ground.”
The disaster in Fukushima heightened public concerns about nuclear safety, leaving Japan with no online reactors since May after all 50 went off line for maintenance checks.
To avoid a summertime power shortage, Hosono, the prime minister and two other ministers, earlier in June approved the restart of two reactors in western Japan. They are expected to be back online in July.
Hosono said that no other reactors will be restarted until a new regulatory agency is set up by September.
Parliament approved a law on Wednesday for a more independent regulatory body. The regulatory agency has up to now been placed under the ministry that also promoted the use of nuclear power, one key factor experts blame for the failure to avert the Fukushima crisis.

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