An aerial view from an aircraft shows a new Safe Confinement (NSC) structure above the old sarcophagus covering the damaged 4th reactor at the Chernobyl Nuclear Power Plant during a tour of the Chernobyl Exclusion Zone, Ukraine, April 3, 2021. REUTERS/Gleb Garanich/File Photo

(Reuters) – Ukraine said on Friday it had recorded an increase in radiation levels from the defunct Chernobyl nuclear power plant, a day after Russian forces seized the site due to military activity that sent radioactive dust into the air.

An adviser to Ukraine’s presidential office said that Russian forces seized the former power plant on Thursday after Russia launched a large-scale invasion of Ukraine. Read more

The still radioactive site of the 1986 nuclear disaster is about 100 kilometers (62 miles) from Kiev.

Experts at the Ukrainian state nuclear agency said that the change was due to the movement of heavy military equipment in the region raising radioactive dust into the air.

The International Atomic Energy Agency said the radiation at the site posed no danger to the public.

“The readings reported by the regulator – up to 9.46 microsieverts per hour – are low and remain within the operational range measured in the restricted area since its inception,” the IAEA said.

IAEA Director-General Rafael Mariano Grossi added that it is of paramount importance that the safe and secure operations of nuclear facilities in the region are not affected or disrupted in any way.

The European Bank for Reconstruction and Development said on Friday that critical plant infrastructure had not been damaged and that essential maintenance work was continuing.

Poland, neighboring Ukraine, said it had not recorded any increase in radiation levels on its territory.

France-based Krerad, the independent nuclear watchdog, said in a statement on Friday that it was trying to verify and review the information in its laboratory.

“If the recorded dose rates are consistent with the real values, then the situation is very worrying,” Kerrad said, adding that more research is needed to interpret the data.

CRIIRAD spokesperson Bruno Charrion said resuspension of soil from military activities, or damage to nuclear facilities, whether it was waste storage or containment structure, could be one of the reasons for high levels of radioactivity.

Another possibility, he said, was that the readings were inaccurate as a result of interference from cyber attacks.

Kerrad said the area has many high-risk facilities, including radioactive waste treatment and storage facilities, most of which are uninsured.

The organization said that other reactors in Ukraine also pose a safety risk in the event of an accident. She said that while the potential risks could have been reduced by shutting down the reactors, Ukraine relies on nuclear power for more than 50% of its electricity supply.

Additional reporting by Pavel Politiuk, Gabriela Bachinska, Forrest Krillin and Nina Chestny; Editing by Raisa Kasulowski and Jonathan Otis

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