SIMULATION OF RADIONUCLIDE PROPAGATION AT EXTERNAL EXTREME EVENTS IN THE NPP AREA

Abstract

At the current stage of electric-power industry development in Ukraine, the issues of energy safety and energy independence are becoming increasingly important. Being the largest among others in Europe, Zaporizhzhia Nuclear Power Plant (ZNPP) has a large dry storage facility for spent nuclear fuel. The armed attack of Russia has endangered nuclear and physical safety in Ukraine. Beginning on 24 February, 2022, the hostilities were activated in the country. The activization of the warfare has led to the capture of the ZNPP by the Russian militaries (4 March, 2022) and to their presence of the ZNPP. This situation causes justifiable concern about the potential detrimental effect on the nuclear and physical safety under service conditions of nuclear power units and at radioactive sourcerelated activities. This paper is concerned with simulation of the radionuclide propagation under external extreme events in the NPP zone, using the ZNPP as an example. The transfer of 137Cs radionuclide has been simulated for the hypothetical ZNPP failure at meteorological conditions as of 23 to 25 August, 2022. According to the simulation data, throughout 23–25 August, 2022, the highest 137Cs concentration values might be observed within the Ukraine territory, particularly in the near-field zone, 50…100 km in radius, from the emission point. Besides, the radioactive impurities could be carried off to the neighboring state areas.