Reactor unit 5 at the Russian-occupied Zaporizhzhia Nuclear Power Plant (ZNPP) was successfully switched to cold shutdown status to conduct maintenance only possible in that state, Director General of the International Atomic Energy Agency (IAEA) Rafael Mariano Grossi said on July 29.
The IAEA reported that unit 5's transfer into cold shutdown status – a mode in which it no longer produces electricity – was conducted on the morning of July 28, three days after unit 4 was brought to hot shutdown.
According to the IAEA, one of the six reactors at the plants needs to remain in a hot shutdown status to generate steam, which helps ensure nuclear safety at the Russian-occupied facility.
But to keep producing the steam required while having all units in a cold shutdown state, which helps minimize the risks of a man-made disaster, the IAEA has called on the management of the Russian-occupied nuclear plant to install an external boiler.
Ukraine has also been calling on the management of the Russian-occupied nuclear plant to switch all reactors into cold shutdown mode.
Nearly a year and a half since Russia swiftly occupied Europe's largest nuclear plant situated in the southeastern Zaporizhzhia Oblast in March 2022, uncertainty about what Russia could do next at the plant remains.
The IAEA reported that the mines that they observed on 23 July at the plant's perimeter were still in place on July 27, and the Russian side has not granted the agency access to the roofs and the turbine halls yet.
The IAEA also said that its on-the-ground team heard some detonations – both distant and apparently closer to the plant – over the last few days.
Ukraine raised fresh concerns of a potential accident at the plant in June, with top officials warning that Russia had rigged the plant with explosives and could launch a terrorist attack.
Since occupying the plant, Russia has used the Zaporizhzhia nuclear plant as a military base, placing troops and equipment there.
Ukraine's HUR military intelligence reported earlier in July that Russia continues to mine the plant. According to the report, mines, and explosives continued to be delivered to the territory of the nuclear plant.
The IAEA staff has been based at the Zaporizhzhia plant on rotation since September 2022, after Grossi's first visit to the occupied facility.
Francis Farrell
(Updated: )
