Assessment of environmental impact from radioactive effluents discharged by the Hanbit nuclear power plants in Korea: analyzing annual reports from nuclear power plants and radioactivity data from environmental monitoring organizations

The aim of this comprehensive study was to analyze the annual effective doses to the public due to radioactive effluents discharged from the Hanbit nuclear power plants (NPPs) in Korea and identify potential improvements for the current environmental radiation monitoring system. We meticulously analyzed the amount of radioactive effluents discharged from the Hanbit NPPs and their resulting doses to the public for a decade (2014-23). Carbon-14, which accounted for only 1.90% of the total activity in radioactive effluents, contributed 88.53% of the annual effective doses to the public. This impact was significantly larger than that of tritium, which constituted most of the radioactive effluents. We propose potential improvements for the environmental monitoring system, including an increase in monitoring points and cycles of the seawater and seabed sediments to consider the characteristics of oceanic dispersion and the implementation of a radioactivity analysis of carbon-14 in ingestion and respiration-related environmental samples.