Japan eyes using decontaminated Fukushima soil at 2027 green expo in Yokohama

YOKOHAMA – The Japanese government is considering using soil collected during decontamination work at the Fukushima No. 1 nuclear power plant at the International Horticultural Expo 2027 (Green x Expo) to be held in Yokohama in 2027, according to government and ruling party sources.

A plan to use decontaminated soil with low radiation levels – dubbed “reconstruction and revitalisation soil” – in flower beds and other places around the expo venue is under consideration.

The Green x Expo is scheduled to start in March, and the government intends to foster public understanding on the soil’s use elsewhere by emphasising its safety at the major international event.

About 14 million cubic m of decontaminated soil is currently being stored at interim storage facilities surrounding the nuclear power plant operated by Tokyo Electric Power Company Holdings, in the Fukushima towns of Okuma and Futaba.

The plant suffered a nuclear accident in 2011. A law stipulates that the final disposal of the decontaminated soil outside Fukushima Prefecture must be completed by March 2045.

According to the Environment Ministry, three-quarters of the soil has a radiation level of 8,000 becquerels per kg or less.

Even people working in close proximity to such soil would receive an annual radiation dose of 1 millisievert or less, within international safety standards.

There is currently no plan in place for the large-scale use of decontaminated soil.

The government has so far used 68 cubic m of the soil across 10 locations, including the front garden of the Prime Minister’s Office and the grounds of government ministries and agencies in the Kasumigaseki district of Tokyo. It plans to promote the soil’s use at its regional offices as well.

At the 2025 Osaka-Kansai Expo, planters containing 12 varieties of flora, such as akebi, and filled with decontaminated soil were displayed.

Green x Expo’s venue spans about 100 ha of a former US military facility across Yokohama’s Seya and Asahi wards, and will be adorned with 10 million flowering and non-flowering plants.

With 61 countries and international organisations planning to participate, a member of the ruling Liberal Democratic Party said: “The use of reconstruction and revitalisation soil at the horticultural expo, which is a national project, is highly significant.”

The government plans to begin selecting and surveying candidate sites for the final disposal of decontaminated soil, including the portion with relatively high radiation levels, around 2030. THE JAPAN NEWS/ASIA NEWS NETWORK