Korea Hydro & Nuclear Power Co., Ltd. (KHNP) is preparing to construct additional temporary storage facility within Wolsong Nuclear Power Plant as high-level waste storage facility is set to be saturated soon. KHNP already secured 6,300m2 land and it is planning to construct compact dry storage module (MACSTOR) that can temporary store 168,000 bundles before saturation. If it is not able to finish the construction of temporary storage facility before saturation, Nuclear Power Reactors 2,3, and 4 that are responsible for about 2% of power production in South Korea are going to face closure. In June of 2018, KHNP decided to close Wolsong-1 Nuclear Power Reactor in 2022.
◊Current status of heavy-level waste
KHNP is predicting that it will going to take at least 19 months to finish the construction of MACSTOR 7. This means that it needs to start the construction by April of 2020 if it wants to finish the construction before November of 2021 when saturation is expected to take place.
Because high-level waste from a nuclear reactor emits high-heat radiation, high-level waste is stored within wet storage facility of a nuclear reactor for about five years and is temporarily stored within a dry cask storage afterwards.
By the end of the second quarter of this year, saturation rates of wet and dry storage facilities exceeded 83.13% and 96% respectively. A dry cask storage is divided into canister that has one steel cylinder inside of cylindrical concrete and MACSTOR that has 40 steel cylinders inside of cuboid-shape concrete module. Canister 300 that can store 162,000 bundles of high-level waste was saturated in 2010.
There are three necessary conditions to construct MACSTOR 7. Nuclear Safety Security Commission (NSSC)’s approval on change in operation and Ministry of Trade, Industry and Energy’s (MOTIE) management policy on high-level radioactive waste need to be established. Actual construction can start after KHNP sends a structure notification to Gyeongju-si. Every corresponding procedure needs to be finished by March of 2020 at the latest.
“Although there is no legal issue with starting the construction after getting an approval from NSSC and sending in a structure notification before MOTIE’s policy on high-level waste management is established, it is realistically difficult for us to start the construction before MOTIE’s policy is established.” said a representative for KHNP. “However, our goal is to finish the construction before current dry storage facility becomes saturated.”
Besides the dry cask storage of Wolsong Nuclear Power Plant, saturation rates of other dry cask storages at other nuclear power plants (Kori, Hanbit, Hanul) also exceed 70 to 80%. Because these power plants predict that their dry cask storages will be saturated in 2028, it is urgent for them to prepare a measure to manage high-level waste from light-water reactors.
◊Why is it taking so long to get rid of high-level waste?
Focus is on the background on why South Korean Government is so late on expanding high-level waste temporary storage facility within Wolsong Nuclear Power Plant.
Although South Korean Government had attempted to secure lands to construct high-level waste management facilities since 1983, it had failed ten times. Only success is when it decided to construct intermediate and low-level waste disposal facility in Gyeongju by applying Residents’ Voting Act and has been operating the facility since July of 2015. Its plan to secure a land for high-level waste storage facility was faced with opposition from local residents. Some of examples are Ahnmyeong-do in 1990, Gureopdo in 1994, and Buan in 2004.
As a result, preparation of tens of billions of dollars and development of key technologies have been postponed as well. Current level of South Korea’s technology on managing high-level waste is only between 60 and 70% compared to the level of technologies of other advanced countries.
◊Remaining tasks
MACSTOR 7 is only a temporary storage facility. Next task is to construct an interim dry cask storage that can store high-level waste between 30 and 80 years before it is permanently disposed or reprocessed. After high-level waste is stored for about 40 years, emission rate of harmful radiation from high-level waste is reduced to 1% of the original emission rate. There are 22 countries that have interim dry cask storages out of 31 countries that operate nuclear power plants. South Korea is one of the 9 countries that do not have established policy to construct an interim dry cask storage.
Ultimately, there needs to be a facility that can permanently dispose high-level waste. High-level waste can be permanently disposed into land, ocean, space, or ice. IAEA (International Atomic Energy Agency) recommends that disposing high-level waste into the depth of land is the most appropriate way from aspects of economic feasibility and stability.
Finland became the first country to approve construction of a permanent disposal facility in November of 2015. Sweden also selected a land to build a permanent disposal facility in 2009. Considering the fact that it takes about 20 years just to select safe land geologically, South Korean Government needs to establish long-term and comprehensive management policies. During this process, it needs to first present ways to overcome a conflict issue with environmental groups and an accommodation issue with local residents.
High-level waste management policy is closely related to nuclear power plant decommissioning that is being actively promoted by South Korean Government. In order to safely break up and return every facility and equipment from a nuclear power plant back to their normal state, high-level waste needs to be stored in an outside cask storage. Experts believe that nothing will ultimately progress if South Korean Government does not have a measure for interim dry cask storage.
Previously, MOTIE presented its goal of achieving 10% of the shares of nuclear decommissioning market by 2035 and having South Korea become one of top five countries in the world. Its plan is to develop standardization for managing high-level waste, push for development of technology managing high-level waste separately, and establish a standardization system and a safety regulation system between 2020 and 2027. It is also looking into establish ‘high-level waste storage container design approval system’ in order to check safety of a storage container in advance.
Staff Reporter Choi, Jaepil | jpchoi@etnews.com