Survey Reveals Harmful Impact of Nuclear Waste on Japan's Minamitori Island
Minamitori Island, Japan’s easternmost island being considered as a permanent disposal site for high-level radioactive waste, faces new concerns regarding the area’s environmental sustainability. A private research institute has warned that field surveys and construction, which are part of the site selection process, could potentially reduce the conservation value of the island, long known for its unique biodiversity.
An initial feasibility survey of Minamitori Island as a nuclear waste disposal site began last month. This stage is the first part of a three-stage selection process expected to last 20 years before a final site for high-level radioactive waste disposal is determined. The Nuclear Waste Management Organization of Japan, which oversees the project, stated that the survey is conducted based on published geological sources and focuses on studying rock layers and mineral resources. The organisation also asserted that “the ecosystem is not included in the evaluation items.”
This statement sparked concern from the Institute of Boninology, a research institution based in Ogasawara Village, an administrative area of Tokyo. Since the central government proposed the initial survey for Minamitori Island last March, the institute has independently collected and published information about the island’s natural environment. To date, the Institute of Boninology has compiled more than 120 academic papers documenting various rare fish, plant, and wildlife species living on the island. This body of research demonstrates the very high conservation value of Minamitori Island.
Founded on Chichijima Island in 2000 to help protect the ecosystem of the entire Ogasawara Islands in the Pacific Ocean, the institute has been actively conducting wildlife research and environmental conservation activities. Hajime Suzuki, Deputy Director of the Institute of Boninology, believes the currently available data is sufficient to demonstrate the importance of protecting the area. “The knowledge we have today alone is enough to show the conservation value of the island. Its ecosystem must be thoroughly studied before human access to the island increases,” Suzuki said.
Several scientific findings reinforce this view. One is the presence of a rare angelfish discovered around Minamitori Island in 1987. The fish has a spot pattern that changes as it grows and is capable of changing sex from female to male. The waters around the island are believed to be one of its main habitats. In the central part of the island also grows Togemiudonoki, or grand devil’s-claws, a flowering tree from the Bougainvillea family commonly found in Australia and the South Pacific region. This species is not found anywhere else in Japan. Additionally, an ornithological survey in 2022 confirmed the presence of a parent and chick of the white tern, marking the first breeding record of the species in Japan in 120 years.
The Institute of Boninology warns that environmental risks do not only arise during the initial survey stage. According to the institute, the preliminary investigation stage will involve drilling activities at the site, while the detailed investigation could potentially trigger the construction of underground facilities that may cause significant environmental changes. On this basis, Suzuki urged that field research led by the local community be conducted immediately to ensure all ecological values of Minamitori Island are documented and considered before further development processes take place.