Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) has started to transfer reactor unit 4 from hot shutdown to cold shutdown to determine water leak which has also been experiencing major off-site power problems since the conflict began in early 2022, exacerbating the nuclear safety and security risks.
“Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) has started to transfer reactor unit 4 from hot shutdown to cold shutdown,” said IAEA, Director General Rafael Mariano Grossi.
This is being done to determine the precise cause of the water leak that has been detected and to conduct maintenance to repair the affected steam generator. There was no radiological release into the environment. At the same time, over the next three days, ZNPP will move unit 6 to hot shutdown to continue steam production on site.
Unit 6 has been in cold shutdown since 21 April, to enable inspection and maintenance of the safety systems. During the week, the IAEA experts were informed that ZNPP has been conducting specific maintenance on parts of unit 6 safety systems and ZNPP has stated that this work and all tests of the safety systems were successfully completed before commencing the transition of unit 6 to hot shutdown. The IAEA team on the site will closely monitor the operations for the transition between the shutdown states of Units 4 and 6.
The other units at ZNPP remain in a cold shutdown.
As previously reported, the Ukraine national regulator – SNRIU – has issued regulatory orders to limit the operation of all six units to a cold shutdown state.
Meanwhile, the repeated power cuts meant ZNPP has had to rely on its only remaining off-site power line.
“The repeated power line cuts underline the continuing precarious nuclear safety and security situation at the plant,” Director General Grossi said.
Also, the IAEA experts at the Khmelnitsky, Rivne, and South Ukraine NPPs and the Chornobyl site reported several nationwide air-raid alarms raising concern over the safety of nuclear plants. Though they reported that the safety and security at the facilities was not affected.