Concerns have been raised that South Korea's inclusion on the sensitive country list designated by the U.S. Department of Energy (DOE) may complicate the approval for reprocessing spent nuclear fuel, which is essential for the country's future nuclear energy independence. South Korea, which operates 25 nuclear reactors, produces more than 700 tons of spent nuclear fuel each year, but lacks the permission to reprocess it independently and currently stores it in internal pools at nuclear power plants. South Korea has been pushing for amendments to the South Korea-U.S. nuclear agreement to allow for spent nuclear fuel reprocessing.
According to foreign media on the 18th, Daryl Kimball, executive director of the non-profit think tank Arms Control Association (ACA), said in a recent interview with Reuters, "If South Korea is designated as a sensitive country related to nuclear proliferation, the possibility of obtaining U.S. approval for uranium enrichment and spent nuclear fuel reprocessing that can be used for nuclear weapons production must be completely ruled out." This suggests that the U.S. could raise the level of nuclear regulation regarding South Korea.
Kimball also noted, "The guidelines of the Nuclear Suppliers Group (NSG) require supplier countries to refrain from transferring uranium enrichment and reprocessing technologies to countries in regions of proliferation concern." Established in 1974 to prevent the proliferation of nuclear weapons and control the transfer of sensitive materials and equipment related to nuclear technology, the NSG includes both South Korea and the U.S.
Spent nuclear fuel consists of uranium materials used in nuclear power generation and has high heat and radioactivity. Naturally occurring uranium mined from the ground contains about 0.7% uranium-235 and approximately 99.3% uranium-238, but only uranium-235, which undergoes nuclear fission, is used as nuclear fuel. The uranium fuel is utilized after being enriched to a uranium-235 content of approximately 3 to 5%.
Nuclear fuel can no longer be used for power generation after about 3 to 5 years, as the uranium-235 content decreases to around 1%. At the same time, the fissioned uranium transforms into various radioactive substances. Through physical and chemical methods, reprocessing this spent nuclear fuel can extract materials that can be reused as nuclear fuel, such as plutonium-239. South Korea imports over 700 tons of raw material from abroad each year and generates a similar amount of spent nuclear fuel annually. As of the end of last year, over 19,000 tons of spent nuclear fuel has been stored domestically, and it is known that about 96% of it can be reused through reprocessing.
The technology for reprocessing spent nuclear fuel is subject to very strict international controls, as it can be used to separate and enrich plutonium-239 for nuclear weapons manufacturing. Since the signing of the South Korea-U.S. nuclear agreement in 1974, South Korea has not received approval for uranium enrichment and spent nuclear fuel reprocessing for over 50 years.
In contrast, Japan can produce low-enriched uranium, under 20% concentration, which can only be used as nuclear fuel, without U.S. approval under the amended U.S.-Japan nuclear agreement from 1988. Japan has been reprocessing nuclear fuel through overseas contracting and has been importing and storing the extracted plutonium back into the country.
South Korea has been pushing to amend the nuclear agreement to gain authorization similar to Japan's. The nuclear agreement was partially amended in 2015, but South Korea still cannot reprocess spent nuclear fuel or enrich uranium domestically without U.S. approval. The revised South Korea-U.S. nuclear agreement from 2015 only permits the overseas contract reprocessing of spent nuclear fuel. However, experts believe that entrusting reprocessing overseas is impractical when considering factors such as economic viability, safety, public acceptance, and nuclear non-proliferation issues.
Since 2011, South Korea and the United States have jointly developed a spent nuclear fuel reprocessing technology known as pyroprocessing through the Korea-U.S. Joint Fuel Cycle Research (JFCS) for 10 years. Pyroprocessing is a technology that electrochemically processes spent nuclear fuel at high temperatures (500 to 650 degrees) to separate and recover various nuclear materials based on their characteristics, reducing the volume of waste and recycling some back as fuel.
The Ministry of Science and ICT released a report in 2021 detailing the JFCS outcomes, stating that pyroprocessing technology is feasible and suggested further research is needed. Currently, the Korea Atomic Energy Research Institute is continuing the pyroprocessing development in collaboration with the Idaho National Laboratory (INL) under the U.S. Department of Energy.
Some expressed concerns that the designation of sensitive country may complicate future negotiations with the U.S. regarding spent nuclear fuel reprocessing. Currently, spent nuclear fuel generated domestically is stored temporarily within the nuclear power plant sites. Academia predicts that the saturation of the Hanbit Nuclear Power Plant, the Hanul Nuclear Power Plant, and the Gori Nuclear Power Plant will occur sequentially starting in 2030.
The validity of the sensitive country designation will take effect on the 15th of next month. Minister of Trade, Industry and Energy An Deok-geun is expected to visit the U.S. again this week to request the exclusion of South Korea from the sensitive country list.