The NRA said “deficiencies” were found at some of the nuclear facilities after the 7.3 magnitude quake and the operators were dealing with them.
As of 13:30 local time on Thursday, 17 March, it added, there were no reports of issues giving rise to safety concerns at the nuclear sites located in the region. The NRA earlier told the IAEA that the earthquake had not caused elevated radiation levels at the plants.
The earthquake struck around 60 km off Japan’s coast shortly before midnight local time on 16 March, a force strong enough to move some of the hundreds of the seismically-qualified tanks where treated water is stored following the 2011 Fukushima-Daiichi accident by between two and 10 centimetres, but there was no leakage, the NRA said.
Japan is planning to discharge the treated water into the sea under a policy announced in April 2021.
Also at Fukushima-Daiichi, whose six reactor units are in permanent shutdown, a cooling pump at the spent fuel pool of reactor Unit 5 temporarily stopped working but later resumed operating and cooling functions at the site are maintained, the regulator said.
There was no damage at the Onagawa nuclear power station, the NRA said earlier. At the Fukushima-Daiini Nuclear Power Station, currently under decommissioning, the spent fuel pool pumps in reactor Units 1 and 3 stopped for a period but are now fully functioning.