The nation's nuclear watchdog approved a plan Wednesday to decommission two reactors in Fukui Prefecture, a move their operator decided to take rather than shoulder the high cost of implementing safety upgrades.
Kansai Electric Power Co. will spend ¥118.7 billion to dismantle the Nos. 1 and 2 units at the Oi nuclear power plant, with work expected to wrap up in the fiscal year ending March 2049.
The units, which each have an output capacity of more than 1 million kilowatts, are the most powerful reactors to be approved for decommissioning by the Nuclear Regulation Authority since a magnitude 9.0 earthquake and subsequent tsunami caused a meltdown at the Fukushima No. 1 plant in March 2011.
Following the disaster, the government placed a 40-year limit on the lifespan of reactors in the country, with a possible 20-year extension if strict safety standards are met.
As both units came online in 1979 and were approaching the 40-year limit, Kansai Electric had a choice of applying for the extension or scrapping them.
In December 2017, the utility announced it would scrap the aging reactors, citing the high cost of implementing additional safety measures. Kansai Electric submitted the decommissioning plan to the authority in November 2018.
The plant's Nos. 3 and 4 units came online in 1991 and 1993, respectively, and are currently active.
Around 23,000 tons of low-level radioactive waste will be remain following the dismantling process, according to the plan, along with another 13,200 tons of nonradioactive waste.
The plan does not state where the waste will be stored.