The call might have been made to decommission five over-the-hill nuclear reactors, but the problem remains of where to dispose of their total 26,820 tons of radioactive waste.
The plant operators have yet to find disposal sites, and few local governments are expected to volunteer to store the waste on their properties.
The decommissioning plans for the five reactors that first went into service more than 40 years ago was green-lighted by the Nuclear Regulation Authority on April 19.
It is the first NRA approval for decommissioning since the 2011 Fukushima nuclear disaster triggered by the Great East Japan earthquake and tsunami.
That disaster led to a new regulation putting a 40-year cap, in principle, on the operating life span of reactors.
The reactors to be decommissioned are the No. 1 reactor at Japan Atomic Power Co.’s Tsuruga plant in Fukui Prefecture; the No. 1 reactor at Kyushu Electric Power Co.’s Genkai plant in Saga Prefecture; the No. 1 and No. 2 reactors at Kansai Electric Power Co.’s Mihama plant in Fukui Prefecture; and the No. 1 reactor at Chugoku Electric Power Co.’s Shimane plant in Shimane Prefecture.
The decommissioning will be completed between fiscal 2039 and fiscal 2045 at a total cost of 178.9 billion yen ($1.64 billion), according to the utilities.
In the process, the projects are expected to produce 26,820 tons of radioactive waste–reactors and pipes included.
An additional 40,300 tons of waste, such as scrap construction material, will be handled as nonradioactive waste due to radiation doses deemed lower than the government safety limit.
Securing disposal sites for radioactive waste has proved a big headache for utilities.
About 110 tons of relatively high-level in potency radioactive waste, including control rods, are projected to pile up from the decommissioning of the No. 1 reactor at the Mihama plant.
Such waste needs to be buried underground deeper than 70 meters from the surface and managed for 100,000 years, according to the NRA’s guidelines.
In addition, the decommissioning of the same reactor will generate 2,230 tons of less toxic waste as well, including pipes and steam generators.
Under the current setup, utilities must secure disposal sites on their own.
Kansai Electric, the operator of the Mihama plant, has pledged to find a disposal site “by the time the decommissioning is completed.”
But Fukui Prefecture, which hosts that plant and others, is demanding the waste from the Mihama facility be disposed of outside its borders.
The project to dismantle the reactor and other facilities has been postponed at Japan Atomic Power’s Tokai plant in Ibaraki Prefecture because the company could not find a disposal site for the relatively high-level waste.
The decommissioning of the reactor had been under way there since before the Fukushima disaster.
The expected difficulty of securing disposal sites could jeopardize the decommissioning timetable, experts say.
Even finding a disposal site for waste that will be handled as nonradioactive has made little headway.
What is more daunting is the hunt for a place to store high-level radioactive waste that will be generated during the reprocessing of spent fuel, they said.