More than two months after a mysterious radioactive cloud was detected over Europe, Russia's nuclear industry went public Friday in an attempt to dispel fears that one of its facilities had released a plume of ruthenium-106.
Russia's state nuclear corporation, ROSATOM, released the findings of a special commission, which concluded that the Mayak nuclear reprocessing plant, near the border with Kazakhstan, could not have been the source of ruthenium-106, a radioactive isotope.
"There is no scientific basis for the hypothesis of some of our Western colleagues that there was a big release at Mayak," Rafael Arutyunyan, deputy director of Nuclear Safety Institute of the Russian Academy of Sciences and a member of the commission, said at a press conference in Moscow.
European monitoring stations first picked up traces of ruthenium in the air in late September. While concentrations were too low to pose a health risk in Europe, scientists have been puzzling over its origin. Wind patterns pointed to the south Urals, where the Mayak facility is located. The plant was the site of a 1957 explosion widely considered to be one of the world's worst nuclear disasters.
The same day, Mayak flatly denied that the spike in ruthenium had anything to do with its activities.
The ROSATOM commission that inspected the Mayak facility afterward reached the same conclusion. The commission said it hadn't detected abnormal levels of ruthenium at the facility, there had been no malfunction of monitoring systems and none of 250 Mayak employees tested had shown any trace of the isotope.
Arutyunyan rejected the suggestion that officials have been slow in informing the public, saying there had been no emergency situation that would have warranted an alarm. He called talk of a danger to health "nonsense."
"Why should we come running to announce something? Mayak told us that all their systems were working absolutely normally and routinely," he said. "Why should they have jumped up and shouted? I think we spent the right amount of time to understand what happened."
Environmental activists and government critics disagree.
After the findings of the commission were released, Greenpeace Russia started a petition drive addressed to the general prosecutor's office, demanding an investigation by independent specialists and public figures into a possible release of ruthenium from Russian territory, as well as into the possible concealment of information by ROSATOM.
"The question is not only about the immediate danger, but the origin of this release," Greenpeace energy campaigner Rashid Alimov said in a phone interview. "We think such incidents should be investigated and there must be an answer."
Finding the source of the radioactive cloud was beyond the scope of the ROSATOM commission. But because the ruthenium-106 over Europe was found alone, i.e. unaccompanied by other radioactive isotopes, the commission said nuclear power plants or spent nuclear fuel processing facilities like Mayak could be excluded as sources because they don't produce "pure" ruthenium-106.
The commission said a satellite – or a fragment of one – re-entering the atmosphere cannot be completely ruled out as the source of the ruthenium.
According to French authorities, the International Atomic Energy Agency found that no satellite containing ruthenium had fallen back to earth during the period in question.
The elephant in the room, of course, is the 1986 Chernobyl nuclear accident, when Soviet authorities lied for days about the scope of the disaster.
"What's happening with the ruthenium cloud reminds me a lot of what went on with Chernobyl," Russian opposition leader Alexei Navalny said in a recent video blog. "In no way do I want to prove there's been a catastrophe of that scale. I just want to say that the pattern of behavior is exactly the same."
Navalny went on to pillory the headline on state television that "safe ruthenium rain fell on Bashkiria" and the chief oncologist of Chelyabinsk region, who advised people worried about high ruthenium levels "to watch soccer and drink beer."
ROSATOM insists it's being as transparent as possible.
"Russia's nuclear industry is a lot more open than our peers'," ROSATOM spokesman Andrei Ivanov said at the press conference.
On Friday, local journalists were let into Mayak on the first press tour since the facility was identified as a possible source of the ruthenium cloud.
Foreign correspondents will have to wait up to two months to get a security clearance.