Radiological assessment of a potential accident scenario at the Akkuyu Nuclear Power Plant: TEDE, respirable time integrated air concentration, and ground surface deposition under different stability classes

The operational readiness and construction process of Akkuyu NGS, T & uuml;rkiye's first nuclear power plant, is ongoing. This situation necessitates atmospheric accident analyses for the nuclear power plant. While such accident analyses are generally available for nuclear facilities, the fact that one side of the Akkuyu site is surrounded by sea and the other by mountains makes it critical to perform radiological dispersion analyses that take into account different atmospheric stability conditions. The change and analysis of the total effective dose equivalent (TEDE), respirable time-integrated air concentration (RTIAC), and ground deposition parameters of the pollutant released after a plant accident under different stability classes is of critical importance in emergency planning. Using local meteorological data from 2019 to 2023 and the HotSpot dispersion code, key radiological parameters such as Total Effective Dose Equivalent (TEDE), respirable air concentration (RTIAC), and ground deposition were evaluated. The findings reveal a critical situation determined by atmospheric stability. In the highly unstable Class A, it causes severe and high dose exposure near the plant area, while in Class D analyses, dose exposure is at lower concentrations, but the spread affects a wider geographical area. These results highlight the importance of a specially designed emergency strategy for the Akkuyu NGS site that distinguishes between Class A emergency local response and Class D large-scale intervention and protective actions.