On May 27, at 10:45 p.m. GMT, a pressured air explosion occurred in one of the auxiliary facilities of Novosibirsk Chemical Concentrates Plant.

– The incident occurred at the facility which does not deal with radioactive or chemical components, Vladislav Petrov, press spokesman for Minatom, said in an interview with Bellona Web. – There were no release of radioactivity into the environment, added Petrov.

Novosibirsk Zavod Khimkonsentratov joint stock company was established in 1949 to produce fuel elements for 13 plutonium production reactors located in Chelyabinsk-65, Tomsk-7 and Krasnoyarsk-26. It also used highly enriched uranium recovered from the plutonium reactor fuel to make cores for tritium production reactors. It later used fuel pellets from Kazakhstan to produce fuel pins and assemblies for various reactors, but specialised in fuel for research reactors and VVER-1000s. Today the plant produces the fuel pellets for these assemblies. Apparently the tank which suffered the incident contained highly enriched uranium for fabrication of fuel for research reactors, with an enrichment level of up to 26%.