[Report] Radiation Level '0' at Bangpyejang Entrance... Waste Storage Withstands Jindo 6.5 Earthquake Easily

Visiting the Only Nuclear Waste Disposal Site in Gyeongju, Korea

▲The Gyeongju radioactive waste disposal site’s underground cave disposal facility, located 130 meters below ground, is constructed with 1.2-meter-thick concrete.
[Photo by Asia Economy DB]

"Light leaves debt... To operate nuclear power plants without leaving debt to future generations, a radioactive waste disposal facility is necessary."

On the 30th of last month, I visited Bonggil-ri, Yangbuk-myeon, Gyeongju-si, Gyeongbuk Province. Following the coastal road in front of Gampo, the only radioactive waste disposal site (RWDS) in Korea operated by the Korea Radioactive Waste Agency is located there. Upon arriving at the entrance of the Stage 1 underground disposal facility for low- and intermediate-level radioactive waste, located 130 meters underground on a hill overlooking the sea, I donned protective clothing and a safety helmet before entering. Low- and intermediate-level radioactive waste is a byproduct of spent nuclear fuel management with low radioactivity concentration.

Inside the facility, at the end of corridors extending in all directions, I saw a huge cylindrical structure called the disposal silo, measuring 23.6 meters in diameter and 50 meters in height. There are six silos in total. Each silo’s upper level is equipped with a crane to move and stack the waste inside. Radioactive waste is stored in 200-liter drums, which are then placed 16 drums per concrete disposal container. The crane stacks these concrete disposal containers neatly inside the silo. The Stage 1 underground disposal facility was completed in 2014 and began storing waste in July 2015.

The facility can accommodate 100,000 drums based on 200-liter drums. As of the end of last month, about 27,000 drums have been stacked. After stacking the drums filled with waste up to about 35 meters from the 50-meter height, the upper part is covered with crushed stone and sealed with cement for permanent preservation. The waste is protected by multiple layers of crushed stone, concrete barriers, and topsoil, ensuring zero radiation leakage. The portable radiation dosimeter received at the cave entrance showed 0 millisieverts (mSv), indicating no radiation detected. Considering the average radiation dose in daily life is 0.117 mSv, the radiation here is even lower than natural background radiation.

The construction site of the near-surface disposal facility for low- and intermediate-level radioactive waste located in Bonggil-ri, Yangbuk-myeon, Gyeongju-si, Gyeongbuk

After exiting the Stage 1 underground disposal facility, I moved to the surface disposal facility. Since it is located outside the cave, it is designed to dispose of low-level or lower radioactive waste with low radioactivity concentration. The facility is about 80% complete with a target completion date in 2024. Covering an area of 67,490 square meters, 20 disposal silos are being constructed to handle 125,000 drums of radioactive waste. The project budget is approximately 260 billion KRW, and seismic design has been added to withstand earthquakes up to magnitude 7.0.

From the surface disposal facility, I took a bus to the high-level radioactive waste dry storage facility located within the Wolseong Nuclear Power Plant site, managed by Korea Hydro & Nuclear Power. High-level radioactive waste refers to spent nuclear fuel. Spent nuclear fuel is uranium fuel that has been used and exhausted in the reactor, generating high heat up to 300 degrees Celsius and radioactivity. Currently, Korea does not have a permanent disposal facility for high-level radioactive waste; only temporary storage is possible. As nuclear power plant usage increases, the amount of high-level radioactive waste grows, making the construction of a permanent disposal facility urgent.

Macster, a dry storage facility for high-level radioactive waste

Inside, 300 white cylindrical pillars stand in rows above ground. These are canisters for dry storage of high-level radioactive waste, each 16.5 meters tall, equivalent to a five-story apartment building. Each canister can store 5,400 assemblies. Up the hill above the canisters is the "Moxter" (Dense Storage Facility). The Moxter can store about 24,000 assemblies, roughly four times more than a canister. Currently, 14 Moxters have been constructed on the site. The Moxter is a reinforced concrete structure 1 meter thick, capable of withstanding earthquakes up to magnitude 6.5. A KHNP official stated, "Even in aircraft collision tests, the building interior remains intact."

The problem is that 7 out of the 14 Moxters are already full. Seven Moxters were built and operated since 2009, but as they reached capacity, another 7 were constructed. The remaining 7 are also expected to reach capacity by 2037, considering average nuclear plant operation. Although additional Moxters can be built within nuclear plants to store high-level radioactive waste, this is only a temporary measure. Nationwide, the storage capacity for high-level radioactive waste at domestic nuclear plants is expected to reach saturation sequentially, starting with Hanbit Nuclear Power Plant in 2030. This underscores the need to enact a special law to establish a permanent disposal facility. The biggest delay factor is low local acceptance due to the perception of disposal facilities as undesirable. A KHNP official said, "To avoid leaving debt for future generations regarding nuclear power use, a special law must be enacted to establish a foundation for stable radioactive waste management."