L.I. Pavlovlskyi, D.V. Gorodetskyi, V.V. Derenhovskyi, Ye.A. Menshenin, S.G. Brylka
Institute for Safety Problems of Nuclear Power Plants, NAS of Ukraine, 36a, Kirova st., Chornobyl, 07270, Ukraine
DOI: doi.org/10.31717/2311-8253.25.1.5
Abstract
In 2004−2008, in order to reduce the risks of collapse of unstable structures of the Shelter object, a number of measures were taken to stabilize them. These measures made it possible to ensure an acceptable level of the Shelter object safety until the end of 2023, after which work on dismantling of critically unstable structures was to begin. Due to the military aggression of the Russian Federation against Ukraine, the design of works on unstable structures dismantling of the Shelter object was suspended, and the planned start date of dismantling works was postponed indefinitely. Due to the delay in the dismantling of unstable structures and the expiration of the safe operation period of the containment structure of the Shelter object, there was a need for a technical justification for extending its operation period. The purpose of this work is to analyze the dynamics of the radiation situation parameters in some areas of unstable structures dismantling of the Shelter object for the period from 2021 to 2024, as well as to determine the trend in the dynamics of their values for the next period until 2029. The radiation exposure dose rate in the areas of future zones of work on unstable structures dismantling of the Shelter object (in terms of early dismantling) did not undergo significant changes during the period from 2021 to 2024. It is likely that during the next period from 2025 to 2029, the value of this indicator will also not undergo significant changes. A comparison of research data on unfixed surface contamination of the working areas on the roofs of the Shelter object in 2021 and 2024 indicates a certain trend of increasing total dust mass, as well as an increase in activity in the composition of unfixed surface contamination. Accordingly, during the next period – from 2025 to 2029, there will likely be an accumulation of dust mass on the roofs of the Shelter object with an increase in the total activity of unfixed surface contamination.
Keywords: Shelter object, life extension, radiation situation.
References
1. Resolution of the Board of the State Nuclear Regulatory Commission of Ukraine dated 19.10.2023 No. 03 “On the results of the state nuclear and radiation safety examination of the Report on the safety reassessment of the operation of the containment structure of the Shelter object (CS SO) with justifications for the possibility of continuing its operation until 31.10.2029 at the level of safety of the CS SO not lower than that achieved after the completion of emergency stabilization”, approved by the order of the State Nuclear Regulatory Commission of Ukraine dated 24.10.2023 No. 542. (in Ukr.)
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