A Systematic Approach to the Development of a Methodology for Comparative Analysis of Scenarios for the Shelter Object Transformation into an Ecologically Safe System

Abstract

A comprehensive assessment of the impact of wildfires in the Chornobyl Exclusion Zone on the adjacent territory within a radius of 100 km in the spring of 2020 and 2022 was carried out, considering the potential and realized radioecological criticality of the territory. The realized radioecological criticality was expressed in the estimated specific activity of 137Cs in plants, which was formed as a result of aerial and root pollution of agricultural vegetation in farm fields and gardens during the transfer and deposition of radionuclides during fires. The specific activity of 137Cs in plants was calculated based on the data on the integrated volumetric activity of 137Cs, obtained by the WRF-LEDI model of atmospheric transport, using the set of models “AeralPlant — SoilPlant” depending on the biological stage of plant development. According to the results of the calculations, thematic mapping was carried out with the selection of zones of maximum and minimum contamination of the territory, taking into account potential radioecological criticality. Regardless of the volume activity of 137Cs in the air and the direction of air transfer, the spatial nature of the distribution of the most critical areas is preserved. As a result, the most critical areas were identified, where dangerous levels of radiation exposure on the population are possible due to atmospheric transport of radionuclides caused by wildfires and extreme weather phenomena (dust storms) in the Chornobyl Exclusion Zone. Different scenarios of the regional land use structure were considered and thematic assessment maps were built, which are the basis of preventive planning of rehabilitation measures in case of critical situations in accordance with radiation safety norms.