Radioactive leaksRadioactive material, leaked from a Russian nuclear complex, detected over Europe

Published 21 November 2017

The Russian state meteorological agency Roshydromet today released data which show exceedingly high atmospheric concentration of ruthenium-106 in the area where the Rosatom Mayak nuclear complex, located in the Southern Urals. The late-September leak, initially denied by Roasatom, the operator of the complex, caused the radioactive material to spread over northern Europe, where it was detected by IRSN and BfS, the French and German nuclear safety agencies, respectively.

Responding to an access to information request from Greenpeace, the Russian state meteorological agency Roshydromet today (Tuesday, 21 November) published data that show that the agency had found last September the highest concentration of ruthenium-106 in the area where the Rosatom Mayak nuclear complex, located in the Southern Urals. Roshydromet’s findings coincide with earlier findings from the French nuclear research agency IRSN and the German agency for radiation protection BfS.

Greenpeace Russia says that based on these data, Greenpeace Russia will send a letter to the office of the public prosecutor to request an investigation into possible concealment of a radiation accident and for the release of information on the status of the environment in the affected area and beyond. It also demands a check whether the atmospheric radionuclide monitoring system is sufficiently prepared for possible accidents, and whether public health issues related to a possible release of Ruthenium 106 were considered, and public healths sufficiently protected.

According to previously published IAEA data, in late September – early October, Ruthenium-106 was found in the atmosphere in many European countries. The German radiation protection agency BfS came to the conclusion that the source of the emissions of the radioactive substance was most likely located in the Southern Urals. The French nuclear research and safety agency IRSN confirmed this conclusion.

Rosatom called the conclusions of the German and French nuclear agencies inconsistent. The Russian energy company said that in the period of 25 September – 7 October, according to the results of aerosol sampling done by Roshydromet, Ruthenium-106 was not found anywhere except in one single area – Saint-Petersburg. Today (Tuesday), however, Roshydromet published a more complete set of data in response to an access to information request by Greenpeace Russia.

The agency’s report for September shows that the highest concentrations of ruthenium-106 were found in localities around the Mayak complex in the Chelyabinsk region in the Southern Urals. Mayak is a dual-purpose military/civilian nuclear complex which, among other things, reprocesses spent nuclear fuel and processes different forms of radioactive waste.

Roshydromet has also indicated that in that in late-September – early-October, the atmospheric conditions enhanced the transfer of big air masses with pollutants from the Southern Urals to the Mediterranean and up to Northern Europe. Until now, this had officially been denied.

Due to its relatively short half-time of one year, Ruthenium-106 only exists as a human-made substance which is normally not present in the atmosphere. Even small concentrations, therefore, indicate an accidental release. Roshydromet assessed the Ruthenium-106 rate in the air and fall-out samples as “extremely high” and “high contamination.”

The French IRSN estimated that the initial discharge could be as high as 100-300 TeraBequerels, 10,000 times the annual allowed limit of emissions of ruthenium-106 and its decay product rhodium-106 combined. IRSN indicated that such a release should lead to protective measures for people in a radius of several kilometers.

An emergency discharge of ruthenium could be connected with the process of nuclear waste vitrification. Another possibility is that materials containing ruthenium-106 were placed in a metal remelting furnace. Both these activities take place in the Rosatom complex at Mayak.