Analysis of radiation contamination of the environment in a forest area outside the territory of Siberian chemical plant

Abstract

The chemical explosion that occurred on 6 April 1993 at the Radiochemical Works (RCW) of the Siberian Chemical Combine (SCC) in Tomsk-7 (now Seversk) represents one of the most significant non-reactor nuclear accidents in the history of the nuclear fuel cycle. Classified as INES Level 3, the accident was triggered by an uncontrolled «red oil» reaction during PUREX reprocessing, releasing approximately 30 TBq of beta/gamma fission products and about 6 GBq of ²³⁹Pu. This paper presents a comprehensive assessment integrating historical documentation, peer-reviewed literature, IAEA safety reports, and original field measurements using an Atom Fast electronic dosimeter and an MKC-01CA1 dosimeter-radiometer to evaluate current radiological conditions at a previously identified high-deposition site