South Korea’s now-retired Kori NPP unit 1 in Busan is now undergoing a decontamination process in the run up to dismantling. After some 40 years of service starting April 1978, Kori 1, South Korea’s oldest reactor, was permanently closed in June 2017.
Korea Hydro & Nuclear Power (KHNP) said it began the chemical decontamination process to remove radioactive materials from the reactor, which is deemed a crucial first step in the decommissioning procedures although KHNP will need approval from the Nuclear Safety & Security Commission (NSSC) before dismantlement can begin. However, the can only authorise the decommissioning of the reactor after the decontamination has been completed.
Following the Commission’s approval, used nuclear fuel will be taken out of the reactor, followed by the dismantlement of its nonradioactive structures and radioactive structures, as well as the restoration of the reactor site.
The company employs indigenous technologies and equipment for the decontamination process, which is expected to allow Korea to make inroads into the global nuclear decommissioning services market. “The successful dismantlement of a power plant carries significance in the industry ecosystem. The Kori-1 reactor project is expected to serve as a chance to boost the competitiveness of the industry,” a KHNP official said.
It generally takes 7-8 years to complete a decommissioning process. But it is not yet clear how long it will take for the Kori-1 as the issue of building temporary storage for used fuel remains unresolved.
Meanwhile, KHNP is using robots to help with the work. One is a four-legged autonomous robot that KHNP has been developing since 2021. The other is an indoor autonomous flying robot. The robots are equipped with multiple cameras and radiation sensors, and the ground robot also has temperature and humidity sensors. Together with 3D Lidar technology – a laser-based method of imaging shapes using reflected light – these sensors can be used to “visualise” radiation dose information and monitor dangerous areas to ensure the safety of workers.