FUKUI – The mayor of a town in Fukui Prefecture that hosts a nuclear power plant that just restarted one of its reactors has floated the idea of installing dry cask storage within the plant to keep ever increasing amounts of spent fuel there.
Takahama Mayor Yutaka Nose’s idea, though only a suggestion, is rare for someone in his position. Nuclear fuel is supposed to be removed from a power station when it reaches the end of its usefulness. The plant in question is run by Kansai Electric Power Co., which rebooted one of the Takahama reactors earlier this month.
At the same time, Nose called for the central government to get more involved in projects to build temporary storage facilities for spent fuel outside power plants.
While Kansai Electric has said the site for a temporary storage facility outside Fukui will be finalized sometime around 2020 and that it will start being used around 2030, “There is no guarantee that (a municipality) outside the prefecture would agree to host the facility,” Nose said in a recent interview.
“It’ll be too late if we start thinking about (what to do) after the spent fuel pools become full. We need to have a backup plan in case (Kansai Electric’s temporary storage project) goes nowhere,” he said.
Nose has effectively raised the option of building dry cask storage in the Takahama plant and keeping more of its spent fuel there while continuing to use the reactors’ existing cooling pools.
Dry cask storage, which involves keeping spent fuel in metal containers, “will reduce the risk” of accidents, Nose said, noting the storage method does not require water or electricity to keep spent fuel cool.
In the man-made Fukushima disaster, which was triggered by the March 2011 tsunami, a station blackout temporarily disabled the cooling functions of the reactors’ spent-fuel pools, leaving a massive amount of fuel assemblies at risk of burning up just like three of its reactor cores did.
“I’m responsible for the lives of town residents. Even if it is impossible to attain 100 percent safety, it is natural that we think about reducing risks. Not that we want to actively seek (spent fuel), but we have to think about the reality that it might remain in Takahama,” he said.
The No. 4 unit of the four-reactor Takahama plant was restarted on May 17 despite persistent public concern over the safety of nuclear power after the Fukushima crisis. Takahama’s No. 3 unit is scheduled to go back online early in June, while the remaining two units are expected to remain offline for the foreseeable future.
Cooling pools at the plant are capable of storing 4,400 fuel assemblies but must be kept short of capacity to allow for fuel exchange work. Altogether, the pools are currently holding about 2,700 fuel assemblies. If all four reactors go back online, the pools will reach capacity in six to seven years.