건설·운영만큼 중요한 원전 해체
미래 산업 선점할 혜안 필요

Currently, nuclear power generation supplies approximately 10% of the world’s total electricity. There are approximately 430 nuclear power plants that have been or are currently being operated commercially in 31 countries worldwide. Considering that the design lifespan of most nuclear power plants is approximately 40 years, more than one-third of these plants have either reached the end of their design life or have been permanently shut down due to economic or technical reasons. The first commercial nuclear reactor in Korea, ”Kori Unit 1,” which began operations in April 19”78, ceased operations in 2017.

Given that humanity has constructed and operated numerous nuclear power plants, it is only natural that some of these nuclear power plants are now reaching the end of their operational life and retiring,” explains Professor Kim Yong-Soo. “Currently, approximately 170 nuclear power plants worldwide have ceased operations. Nuclear decommissioning refers to the process of permanently dismantling these plants so that no trace remains. This includes safely removing radioactive contamination, dismantling facilities, and restoring the site. While South Korea has not yet decommissioned a plant, around 20 nuclear power plants globally have already been dismantled.” Decommissioning involves a step-by-step removal of radioactive materials and dismantling of systems and structures within the plant. The ultimate goal is to restore the site to its original natural state. However, depending on the situation, partial decommissioning may be pursued if some facilities can still be repurposed. Regardless of the approach, Professor Kim emphasizes that decommissioning is not simply the reverse process of construction.

“In the process of generating energy through nuclear fission, various radioactive materials are created. For a plant like Kori Unit 1, which operated for 40 years, radioactive substances would have accumulated throughout the facility. To safely decommission it, it’s essential to first identify where these materials are located, what types they are, and in what quantities. Since it is not simply about dismantling the related facilities, nuclear decommissioning cannot follow the reverse order of construction, nor can it be done carelessly,” Kim noted.

Professor Kim highlights that the most critical aspect of nuclear decommissioning is conducting a radiological characterization of the plant. This assessment serves as the foundation for planning the order of decommissioning, determining how to safely remove radioactive materials, and addressing other safety concerns. The process must also account for the plant's operational history, including any radiological incidents or localized contamination. Removing radioactive contamination is not a one-time task; it requires repeated efforts over several years. While international experience has helped reduce this timeline, the average decommissioning process still takes 10 to 12 years. “Decommissioning is a battle not only against radiation but also against uncertainty,” Kim added. It is a challenging and lengthy process that demands careful preparation, thorough assessment, and rigorous execution.

While concerns about the safety of nuclear decommissioning persist, 20 reactors have already been successfully decommissioned. For reactors that have retired normally without major incidents, such as those at Chernobyl or Fukushima, the risks associated with decommissioning are relatively low. The International Atomic Energy Agency (IAEA) classifies nuclear-related incidents on an eight-level scale from 0 to 7. By this standard, the Fukushima accident was classified at the highest level, 7. In contrast, the maximum incident risk during decommissioning is typically in the 1–2 range.

The United States was the first to begin decommissioning nuclear power plants in the 1980s. To date, the U.S. has dismantled 16 reactors, Germany 3, and Japan 1, placing these countries at the forefront of nuclear decommissioning. While the UK and France have recently begun actively pursuing decommissioning projects, they have yet to complete any. Japan, meanwhile, has lost its competitive edge in decommissioning reactors that retired normally following the Fukushima disaster.

“In addition to Kori Unit 1, which has already ceased operation, 11 domestic reactors are set to reach the end of their design life by 2030. Globally, more than 80% of nuclear power plants are expected to be permanently shut down within the next decade. Decommissioning a single reactor costs roughly KRW 1 trillion, meaning the total market for nuclear decommissioning exceeds KRW 400 trillion. This is a colossal market that could determine a nation’s future competitiveness. If we fail to act now, we may lose the opportunity to lead this strategic industry. We need to build the expertise and capabilities to decommission reactors safely and economically.”

Professor Kim Yong-Soo warned that without adequate preparation, South Korea risks losing its global competitiveness in decommissioning, leaving the dismantling of its domestic reactors in the hands of foreign companies. This would not only jeopardize the country’s economic potential but also place the safety of its citizens at the mercy of external parties. How can Korea secure international competitiveness in nuclear decommissioning? According to Professor Kim, the decommissioning of Kori Unit 1 must serve as a foundation for gaining practical experience, cultivating highly skilled professionals, and preparing for entry into the emerging global nuclear decommissioning market.

“Fifty years ago, when we began nuclear power generation, our country was struggling economically and lacked sufficient technology. We had no choice but to rely on foreign expertise. But today, we have become a nuclear powerhouse, capable of domestic production and even exporting reactors. We must leverage the skills and resilience we’ve built over the years to proactively prepare. If we can take responsibility for the **entire nuclear lifecycle—from construction and operation to maintenance and decommissioning—we will gain tremendous competitive strength,” Professor Kim emphasized.