A senior executive at the Russian nuclear processing plant suspected of being behind a spike of radioactivity over Europe this autumn has admitted that the isotope recorded does emerge as part of the plant’s production cycle but said its levels are negligible.
Russian officials last month reported high levels of Ruthenium-106 in areas close to the Mayak nuclear plant in the Ural Mountains.
The environmental group Greenpeace alleged Mayak could have been the source of a Ruthenium-106 leak, but the plant said it has not extracted the isotope or conducted any other operations that may lead to its release “for many years”.
Yuri Mokrov, adviser to Mayak’s director general, said in a webcast press conference on Wednesday that Ruthenium-106 routinely emerges during the processing of spent nuclear fuel.
Mr Mokrov insisted, however, the plant was not the source of any major leak, saying it does not produce the isotope on purpose and that the emissions that the plant makes are so insignificant “we can only see it in the chimney”.
A Russian panel of experts dispatched to investigate the leak has failed to identify where the isotope came from, but alleged that it could have come from a satellite that came down from its orbit and disintegrated in the atmosphere.
The commission said last week that a thorough inspection of the Mayak plant and its personnel had found no safety breaches.
“There is Ruthenium in spent nuclear fuel, and Mayak during its activities routinely comes across this isotope,” Mr Mokrov said, adding that “actual emissions are hundreds times lower the permitted levels”.
Mayak, in Russia’s Chelyabinsk region, saw one of the world’s worst nuclear accidents on September 29 1957, when a waste tank exploded.
That contaminated 9,200 square miles of territory and prompted authorities to evacuate 10,000 residents from neighbouring regions.