TOKYO -- Japan Nuclear Fuel Ltd. (JNFL) had been inappropriately storing nuclear waste at a nuclear fuel reprocessing plant in Rokkasho, Aomori Prefecture, in northern Japan, including keeping waste in undesignated areas, the country's nuclear regulatory body has revealed.
The Nuclear Regulation Authority (NRA) had instructed JNFL to make improvements in its practices in 2017, but the company had left some of its nuclear waste in places where they were not supposed to be. There has been no confirmation that any of the radioactive substances leaked. There have been a series of shoddy practices uncovered at JNFL, which is likely to call into question the company's attitude.
At the fuel reprocessing plant, uranium and plutonium are extracted from spent nuclear fuel for reuse in nuclear reactors. Highly radioactive waste liquid that is generated in the process becomes nuclear waste when it is solidified in glass. According to the NRA and others, JNFL had been keeping nuclear waste in a building different from the one the waste is meant to be stored in. As for the approximately 160 kilograms of shards of radioactive waste liquid solidified in glass, an appropriate storage method had not been stipulated. There were eight cases of inappropriate storage, some of them spanning the past 19 years.
Inspectors from the NRA Secretariat confirmed inappropriate storage of nuclear waste in August 2017. The regulatory body asked that JNFL correct its practices by August 2019, but only two of the eight cases had been remedied by the end of June 2020.
At a meeting concerning the safety inspection of the nuclear fuel reprocessing plant this past May, the NRA had determined that the plant had effectively met the government's new criteria. JNFL explained that it had intended to consult with the NRA Secretariat once the inspections had taken place. The NRA, meanwhile, says that the situation is exempt from safety inspections under the government's new criteria.
(Japanese original by Hisashi Tsukamoto, Science & Environment News Department)