'No one will guess': Finnish nuclear waste repository for 100,000 years of storage will have no external signs

The world's first permanent nuclear waste repository will open later this year on Olkiluoto, a sparsely populated Finnish island with lush forests in the Baltic Sea, three hours north of Helsinki. "Onkalo" (Finnish for "cavity" or "cave") is one of the most modern facilities of its kind, designed to store nuclear waste 450 meters underground for 100,000 years.

The process of burying nuclear waste begins at the plant, where during sealing, machines extract spent nuclear fuel rods from storage containers and place them in copper and cast iron barrels up to two floors high. After filling these containers weighing around 24 metric tons will be lowered on a lift to the cave, hewn in a crystalline base 2 billion years old, taking 50 minutes. Each repository will accommodate 30-40 such containers filled with concrete. The total capacity of the storage facility is 3250 canisters or 6500 metric tons.

"It is planned that there will be no external signs of the facility. No one will even suspect what is there, regardless of whether we are talking about future generations, future aliens, or someone else," says Pasi Tuohimaa, communications manager at Posiva, the agency that manages nuclear waste in Finland.

Building such a place is easier than convincing the community to accept it. Obtaining such approval can take decades, but it is based on a simple principle.

"One of the principles of geological disposal is the idea that the generations benefiting from nuclear energy should also pay for the solution and participate in it," said Rodney Ewing, a mineralogist and materials scientist from Stanford University and co-director of the Center for International Security and Cooperation.

Finland began searching for a storage site in 1983. Over the decade, the government considered four locations, weighing public opinion together with geological and ecological criteria. Eurajoki, a town with over 9,000 residents, provided the greatest social support and best natural conditions. In 2000, the city council voted to approve the project. Local residents were inclined towards it, as within 13 km in Olkiluoto, two nuclear power units were already located. The third was launched in April 2023 - the station provides a third of Finland's electricity needs.

Source: Gizmodo