While Russian troops poured into Ukraine in February 2022, Rosatom, Russia’s state nuclear corporation was quietly grappling with a major and potentially embarrassing problem emerging in its flagship export reactor in Belarus, internal documents reviewed by the Bloomberg news agency show.

The article, published December 18, includes comments from Bellona nuclear expert Dmitry Gorchakov — who, among the nuclear experts cited, was the only one to agree to have his name published. The report raises concerns about a best-selling reactor that Rosatom has built in numerous countries beyond Belarus, including Hungary and Egypt, and within Russia itself.

Bellona, too, reported on findings by Lithuania’s special services in its March nuclear digest, which indicated several flaws in both reactors at the Belarus plant were being hushed up by Rosatom and Belarusian nuclear authorities.

Тhe Bloomberg report further suggests that international sanctions against Russia for its attack on Ukraine could be complicating Rosatom’s ability to manage a sprawling portfolio of international projects that brings the Kremlin revenue and political influence.

The article drew sharp reactions from Russian officials, including Dmitry Peskov, Vladimir Putin’s spokesman, as well as Mikhail Mikhadyuk, the Belarusian deputy minister of energy.

At issue at the Belarus nuclear plant at Ostrovets was a mysterious and exceedingly rare problem: resin was seeping into the primary circuit of the VVER-1200 reactor, threatening to seize up critical components, the internal corporate documents reviewed by Bloomberg show.

The problem was detected in February 2022 as Rosatom was preparing to launch the the new 1,200-megawatt unit, and the discovery caused the launch to be delayed by more than a year.

The resin leak, had it persisted, could have led to disruption of heat exchange in the reactor core, overheating and damaging the nuclear fuel, and jamming control and protection rods. If such a scenario were to develop in an operating reactor, it would require immediate shutdown and work to diagnose and correct the problem — a time consuming process.

In the worst case, Bloomberg reported, accumulation of so-called ion-exchange resin, which regulates the purity of water flowing through plant channels and pipes, could impede reactor control, elevating the risk of a meltdown if something went wrong once it was online.

The Ostrovets plant has been the focus of wary observation for years. Several mishaps during its construction — including the dropping of an entire reactor vessel — have drawn rebukes and alarm from European officials, many of whom assert to Bloomberg that the plant was built with a lack of skilled labor, with many critical processes rushed under pressure from Rosatom.

At the time the resin leak was discovered, the reactor had not yet been put into operation. By February 2022, the reactor’s nuclear fuel had been loaded and work was underway to prepare for first criticality— the start of the first controlled chain reaction.

Usually, several months pass from the moment of the first loading of fuel into the reactor to the physical start-up, when the reactor first begins to operate at a minimum level as a nuclear power plant. At other VVER-1200 reactors, including the first unit of the Belarusian NPP and four VVER-1200 units built in Russia at the Novovoronezh and Leningrad NPPs, this process took from one to two months.

Problems at the second unit of the Belarusian NPP extended the period of physical commissioning to 15 months – from December 27, 2021 to March 25, 2023. ”

The Belarusian plant’s second unit is now online and was commissioned in November. But the problems with the plant — located just 51 kilometers from the Lithuanian capital of Vilnius — are relevant because the Belarus plant is the foreign debut of Rosatom’s new reactor design. Similar VVER-1200 units are set for commissioning in Bangladesh and Turkey within the next year.

Putin spokesman Peskov, answering questions on the Bloomberg article, focused solely on commissioning work on the unit during the incident.

“The fact is that this cannot be called an emergency situation, because we are talking about commissioning work — this nuance is the most important,” he told reporters.

Undoubtedly, during commissioning work shortcomings can and should be identified. But identifying a problem that requires such a protracted period to correct can hardly be called a normal situation — especially in light of the fact that the Belarusian unit is the sixth VVER-1200 that Rosatom is building.

Mikhadyuk, the Belarusian deputy energy minister, characterized the Bloomberg report as political provocation.

“This attack, which appeared in the media today, is another attempt to denigrate our joint project with Russia — the [Belarusian nuclear power plant],” he said. “Time will tell, and it is already showing, the station is working reliably.”

However, the fact remains: after the launch of the Belarusian plant’s first unit, technical problems were identified that required frequent shutdowns and downtime, the result being that during the first two years of its operation, it was only fully operational half the time. The second unit, as documented by Bloomberg, encountered serious delays already at the start-up stage.

Bellona nuclear project expert Gorchakov, who was a source for the Bloomberg article, again comments on the reaction of Belarusian and Russian officials to the publication:

“The problem with the Belarusian nuclear power plant is not only that we are seeing frequent technical problems and delays in the implementation of this project,” he said.

“Such events often occur at any large and complex projects, including nuclear ones, in different countries. The fact is that in the case of Russia and Belarus, there are several additional factors that increase potential nuclear and radiation risks: this is not only the traditional secrecy of the nuclear industry and its reluctance to openly talk about its problems, but also the politicization of any criticism,” Gorchakov added.

With the outbreak of the war unleashed by Russia in Ukraine, the Kremlin has closed or squeezed out from Russia most independent media and environmental NGOs — organizations that could offer objective information on events of public importance at dangerous sites.

As a result, this vacuum of is filled exclusively by information deemed acceptable by authorities.

Bellona was named an undesirable organization by Kremlin authorities and has since closed its offices in Russia, relocating its staff to Vilnius.

We do not have access to reliable information about the goings on at the Belarusian nuclear power plant. But obvious delays in important stages of plant construction, plus information from numerous unofficial sources, allow us to conclude that not all is going as smoothly as Russian and Belarusian authorities would lead us to believe. On those rare occasions that they admit to difficulties, they do not go into detail.

Bellona’s nuclear project today aims to increase transparency in understanding the processes associated with the Russian nuclear industry, both within Russia and at the level of Rosatom’s foreign projects. We regularly monitor and comment on important events, including those at the Belarusian nuclear power plant. We also analyze nuclear developments in Ukraine, with special emphasis on the Zaporizhzhia nuclear plant, which was captured by Russian forces. These investigations form the content of our monthly atomic digests and our numerous reports. They also form the backbone of our work with Russian and foreign media.

It is critically important in the context of the political and military confrontation between Russia and the West to have a more objective picture of what is happening at nuclear-hazardous facilities — one that does not tolerate either excessive alarmism or false reassurance.

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