Ukraine's Zaporizhzhia nuclear power plant seized by Russian troops: regulator

Russian troops have seized the Zaporizhzhia nuclear power plant in southeast Ukraine after a night of shelling in the vicinity of the facility, the State Nuclear Regulatory Inspectorate of Ukraine said March 4.

The plant, also known as Zaporozhe, is Ukraine's largest, with six 950 MW reactors. Nuclear meets over 50% of Ukraine's power demand.

"The Zaporizhzhia NPP site has been seized by the military forces of the Russian Federation. The personnel continue working at their workplaces, operational personnel monitor the state of power units and ensure their operation in accordance with the requirements of the process procedures for safe operation," it said.

Shelling at the site caused a fire that was extinguished. No change in radiation level had been registered, nor was there any information yet on casualties, the inspectorate said.

Only Unit 4 was in operation, it said, noting output of 690 MW.

Unit 1 was in an outage, Units 2 and 3 disconnected from the grid and Units 5 and 6 were being cooled down.

"The loss of the possibility to cool down nuclear fuel will lead to significant radioactive releases into the environment. As a result, such an event may exceed all previous accidents at nuclear power plants, including the Chernobyl accident and the accident at the Fukushima Daiichi nuclear power plant," the inspectorate said.

Along with its six reactors, the Zaporizhzhia site hosts a spent nuclear fuel storage facility, "damage of which due to shelling will also lead to radioactive releases," it said.

Ukraine has 13.11 GW of nuclear capacity spread across 15 reactors at four sites.

Meanwhile independent generator and coal miner DTEK said it had activated nine of its thermal power units to compensate for the power lost at Zaporizhzhia, a loss it put at 1.3 GW.

"DTEK now has 23 thermal power units in operation instead of the planned 14," it said.

IAEA response

The International Atomic Energy Agency said it was putting its Incident and Emergency Centre (IEC) "in full response mode due to the situation at the Zaporizhzhia NPP," IAEA Director General Rafael Mariano Grossi said.

In a press conference in Vienna March 4, Grossi said active consultations were ongoing to provide assistance at all Ukraine's nuclear sites, but gaining access to a war zone was "very difficult".

"Under present circumstances this is not an easy process. That is why I'm in contact with all sides on how we provide assistance," he said.

The assistance would focus on the physical integrity of facilities, on the efficient operation of safety and security systems, on staffing issues and on ensuring security of outside power to nuclear facilities, he said.