Assessment of the current component of underflooding within the territory of the Chornobyl exclusion zone by the methods of remote sensing technologies

According to the results of the thematic interpretation of the satellite imaging data for the recent years in the territory of the Prypiat Left-Bank Drainage System of the Chornobyl Exclusion Zone, the probable onset of the multi-aqueous phase of water content in the frame of the full hydrological cycle is predicted at the end of 2022. The attribute of multi-water phase emerging is emphasized by statistical data relatively an increase of the total amount of atmospheric precipitation in the cold period during September-October-November-December 2022 and 2023 within the entire catchment basin for the left-bank part of the Prypiat River. These data are fully consistent with the established trend of increasing extents of 90Sr activity, which is carried away with runoff from the left-bank polder area. According to the calculated estimates of 90Sr activity levels, 0.02 and 0.034 TBq could be removed in 2022 and 2023, respectively. This radioactive carryover increased by 6.4 times, if 2021 is compared with 2023 and by 34 times, if 2020 compared with 2023. Thus, a direct relationship is observed between the 90Sr activity levels removed from the territory of the left-bank polder to the Prypiat River with the values 90Sr of the areas of the open water surface mapped by means of remote sensing technologies within its boundaries, and the values 90Sr of the total amount of atmospheric precipitation in the cold period of the year on the adjacent left-bank part of the water catchment basin of the Pripyat River. Hence, the prediction as to the growing 90Sr activity levels due to its removal with the runoff from the area of the left-bank polder to the Prypiat River in 2024-2026, is substantiated.