Analysis of Liquid and Gaseous Radioactive Effluent Trends at Korean Nuclear Power Plants Over the Past Five Years

This study analyzed the trends in radioactive effluent releases and the dose contributions of individual radionuclides from five nuclear power plant sites in Korea over the past five years (2020–2024). Based on the data published in the annual “Environmental Radiation Monitoring Reports” by Korea Hydro & Nuclear Power (KHNP), the cumulative release amounts, emission frequencies, and dose contributions by radionuclide were quantitatively analyzed for both liquid and gaseous releases. The analysis found that tritium (³H) was the most dominant radionuclide released in both gaseous and liquid effluents for all sites. Although significant amounts of ¹⁴C and noble gases such as ⁴¹Ar, ⁸⁵Kr, and ¹³³Xe were occasionally emitted. Among gaseous effluents, ³H, ¹⁴C, ⁴¹Ar, ¹³³Xe, ¹³¹ᵐXe, and ⁸⁵Kr showed high frequencies. For liquid effluents, ³H, ⁶⁰Co, ⁵⁸Co, and ⁹⁵Nb were the most frequently released. In terms of dose contribution, ¹⁴C, ³H, ¹³³Xe, ⁴¹Ar, and ⁶⁰Co were dominant among gaseous effluents, while ¹⁴C, ³H, ⁹⁵Nb, ⁵⁸Co, and ⁶⁰Co were significant among liquid effluents. The results of this study can serve as reference data for predicting future release trends and provide a basis for selecting key radionuclides for validation of the E-DOSE program.