국내 원자력발전소의 Carbon-14 환경배출로 인한 주변주민 피폭선량 분석 연구

Abstract

A study on the public exposure due to carbon-14 release to the environment from Korean nuclear power plants

HWAPYOUNG KIM

Advisor : Prof. Kong Tae Young, Ph.D.

Department of Nuclear Engineering Graduate School of Chosun University

Radioactive effluents generated by the operation of nuclear power plants (NPPs) are classified into gas and liquid effluents depending on the source term and discharge pathways. Gas and liquid effluents generated from NPPs are discharged into the environment during the operation of nuclear facilities. The discharge of radioactive effluents is controlled by three criteria: radioactivity concentration, exposure dose, and the total amount of radioactivity. Among the radioactive effluents discharged from NPPs, 14C is a nuclide with a very long half-life, which is primarily involved in the dose of the public living around NPPs. Radioactive effluents discharged from Korean NPPs contain various nuclides. Korea Hydro & Nuclear Power, the operator of Korean NPPs, controls the effluent discharge. This study analyzed the radioactive effluents discharged from all Korean NPPs during each of the 10 years before (2002-2011) and after (2012-2021) 14C monitoring at pressurized water reactors (PWRs). The dose of the public living around NPPs due to radioactive effluents discharged from Korean NPPs was also analyzed depending on the nuclides. It was found that 3H accounted for a large proportion of radioactive effluents before 14C monitoring at PWRs (2002-2011). As a result, 3H accounted for the largest proportion of public dose, with approximately 80% of the total public dose. Since 14C monitoring at PWRs has been conducted (2012-2021), 3H has still accounted for a large proportion of radioactive effluents, but 14C has accounted for the dominant nuclide for the public dose, with an average of 9×10-2 mSv y-1 for 10 years (2012-2021). 14C has a great radiological impact on the dose to the public living around NPPs. Therefore, it is judged that further study is necessary to reduce 14C discharges and the resulting dose to the public living around Korean NPPs.