CONSEQUENCES OF THE RADIOACTIVE CONTAMINATION OF THE SVERDLOVSK OBLAST CAUSED BY THE ACCIDENT IN 1957 AT THE MAYAK INDUSTRIAL COMPLEX

摘要

Routine activities at the Mayak Industrial Complex for over 40 years as well as the radiation accidents that occurred have led to an unprecedented radioactive contamination level in a considerable part of the Chelyabinsk, Kurgan and Sverdlovsk regions of Russia. Dumping of radiochemical waste with an activity of 2.8 million curies into the Techa river in 1949-1952 resulted in radioactive contamination of the Techa-Iset-Tobol river system. In September 1957, a storage tank for liquid high activity waste at the Mayak site exploded. Radionuclides with an activity of about twenty million curies were released to the environment, of which around two million curies were discharged outside the territory of the Mayak Industrial Complex, thereby giving rise to the East-Ural radioactive trace. The considerable radioactive contamination of the environment and the radiation exposure of the population, especially in the first decades of operation of the enterprise, are due to routine process discharges of radioactive matter to the atmosphere from the Mayak Industrial Complex. The steps taken before 1991 with a view to alleviating the consequences of the radioactive contamination of this area were not adequate to the extent of the ecological and economic damage and the harm done to the health of the population. In 1991, the Government of the former Soviet Union (FSU) decided to develop a State programme for the period up to the year 1995, focusing on medical and psychological rehabilitation of the radiation affected population and on measures to be taken to render assistance to it. This programme was worked out by a group that was formed in the Ural region, including representatives of the Ministry for Atomic Energy of the FSU, as well as of the Administrations of the Chelyabinsk, Kurgan and Sverdlovsk regions, and the Ural Division of the Russian Academy of Sciences, which was represented by the Institute of Industrial Ecology (HE). In 1993, the State programme was officially adopted, and the HE was appointed as scientific co-ordinator and general contractor for assistance of the section dealing with the problems of the territory. Data on the radioecological situation in the Sverdlovsk region have been obtained on the basis of a complex analysis of archival material on the state and dynamics of the radioecological conditions of the territory of the Sverdlovsk Oblast in the period 1957-1995, as well as from a study made by other institutes in 1992-1994. These results are presented in the paper and discussed in detail.