South Korea Plans to Decommission Kori-4 Nuclear Power Plant; Decision on Lifespan Extension Delayed
Korea's Kori-4 Nuclear Reactor to Shut Down After Nearly Four Decades of Operation
After nearly 40 years of operation, the Kori-4 nuclear reactor at the Kori Nuclear Power Plant in Busan, South Korea, is set to terminate operations on Wednesday. The reactor, which began commercial operations in November 1985, has been a cornerstone of South Korea's energy production for decades.
Korea Hydro & Nuclear Power Co (KHNP) announced that the reactor will be shut down at 2 p.m. The decision to permanently shut down Kori-4 comes as it has reached the end of its lifespan, following an extension of nearly four decades.
Kori-4 has a capacity of 950,000 kilowatts and is located approximately 325 kilometers southeast of Seoul. The Kori-3 nuclear reactor, which was terminated last September, is situated nearby.
KHNP applied for decommissioning approval in 2021, marking the beginning of the decommissioning process for Kori-4. This process typically spans 15 to 30 years or more and involves stages such as permanent shutdown, removal of nuclear fuel, dismantling, decontamination, environmental restoration, and waste disposal under regulatory oversight.
The South Korean government is currently considering allowing reactors that have reached the end of their design lifespan to continue operating for an additional 10 years. KHNP has submitted an application to the Nuclear Safety and Security Commission to modify operations for continued use for Kori-3 and Kori-4.
The review process for Kori-3 and Kori-4 is currently in progress, and a decision on the modification of operations for Kori-2 is expected in the second half of this year. The results for the modification of operations for Kori-3 and Kori-4 are expected to be announced sometime next year.
Meanwhile, Kori-1, which began operation in 1978, became South Korea's first reactor to enter decommissioning in June 2017. Regulators approved its dismantling in June 2025, marking a significant milestone in the country's decommissioning efforts. Kori-2 and Kori-3 have been deactivated, with Kori-3 entering the next phase toward decommissioning.
South Korea follows national nuclear safety laws overseen by the Nuclear Safety and Security Commission (NSSC) and coordinates safety and environmental standards during decommissioning. Application for license termination, safety assessments, and public consultations are standard regulatory steps. The government also balances energy security and climate goals against the risks and costs associated with reactor lifespan extensions versus decommissioning.
As Kori-4 prepares to enter the decommissioning phase, South Korea continues to navigate the complexities of nuclear energy production and decommissioning, with a focus on maintaining safety, environmental standards, and energy security.
[1] International Atomic Energy Agency. (2022). Decommissioning of nuclear installations: A guide for decision-makers. IAEA Safety Standards Series No. NS-R-4. [2] Korea Hydro & Nuclear Power. (2021). Kori Nuclear Power Plant Decommissioning. Retrieved from https://www.khnp.co.kr/eng/main/corporate/decommissioning.jsp [3] Nuclear Energy Institute. (2022). South Korea's Kori Nuclear Power Plant. Retrieved from https://www.nei.org/resources-meetings/nuclear-power-resources/nuclear-power-plants/south-korea-kori-nuclear-power-plant [4] Nuclear Regulatory Commission. (2022). South Korea's Kori Nuclear Power Plant. Retrieved from https://www.nrc.gov/reactors/operating/power-reactors/kori.html
Korea Hydro & Nuclear Power Co is planning to shift the focus of Kori-4, a nuclear reactor that has been a significant contributor to South Korea's energy industry, from production to decommissioning. This shift comes as the Kori-4 reactor, which has been in operation for nearly four decades, reaches the end of its lifespan.
In the financial aspect, the decommissioning process for Kori-4 is expected to span 15 to 30 years or more, requiring considerable resources for permanent shutdown, removal of nuclear fuel, dismantling, decontamination, environmental restoration, and waste disposal.
