Nuclear wasteFinnish company to construct final disposal facility of spent nuclear fuel

Published 13 November 2015

The Finnish government has granted a license to Finnish company Posiva for the construction of a final disposal facility for spent nuclear fuel. The spent fuel assemblies will be encapsulated and placed in the bedrock at a depth of about 400 meters for permanent disposal. The waste will be stored for around 100,000 years before its level of radioactivity begins to dissipate. “This is the world’s first authorization for the final repository of used nuclear waste,” Finland’s Economy Minister Olli Rehn said.

Interim storage facility for nuclear waste disposal // Source: posiva.fi

The Finnish government has granted a license to Finnish company Posiva for the construction of a final disposal facility for spent nuclear fuel. After an extensive and multidisciplinary research and development work, Posiva can now proceed to construction of the final disposal facility in Olkiluoto according to the concept it has developed. The final disposal of the spent fuel generated in the Olkiluoto and Loviisa nuclear power plants into the Finnish bedrock is planned to start in the early 2020s.

Posiva says that the government’s favorable decision for Posiva’s construction license application is recognition for the extensive R&D work carried out by Posiva for more than forty years to develop a safe final disposal solution for spent nuclear fuel. After gaining research results and experience from the underground rock characterization facility ONKALO, Posiva is now about to move on to the construction of the final disposal facility on the island of Olkiluoto in Eurajoki in south-west Finland.

“The construction license that has now been granted for our final disposal facility for spent nuclear fuel is a significant achievement for us, our owners and our entire personnel. This pioneering project is important not only for Finland, but also on a global scale. It is the first project entering into construction phase in the whole world. I express my thanks and appreciation to all the experts and partners in Finland and in other countries, who have joined their forces and expertise in this unique and multidisciplinary project,” says Posiva’s president and CEO, Janne Mokka.

Posiva notes that in the final disposal facility, the spent fuel assemblies will be encapsulated and placed in the bedrock at a depth of about 400 meters for permanent disposal. The facility comprises two parts: the aboveground encapsulation plant for the encapsulation of the spent fuel in the final disposal canisters, and the final repository deep in the bedrock, with tunnels in which the spent fuel will be placed.

The tunnels have already been constructed to study and verify the solidity of the area’s rock bed where the waste is to be stored for around 100,000 years before its level of radioactivity begins to dissipate.

This is the world’s first authorization for the final repository of used nuclear waste,” Finland’s Economy Minister Olli Rehn said at a press conference.

The spent fuel will be encapsulated in copper-coated containers, and the containers will be placed deep underground in a hole in the rock, which is then sealed with a buffer of bentonite clay, a volcanic ash that swells when mixed with water.

Posiva specializes in nuclear waste management, and is in charge of the final disposal of the spent fuel generated in Finland by its owners, Teollisuuden Voima and Fortum, as well as for research related to final disposal and other specialized activities in the sector.

The company notes that the Finnish parliament approved the decision-in-principle on the final disposal project in 2001. Posiva submitted the application for the construction license at the end of 2012. In February 2015, the Finnish Radiation and Nuclear Safety Authority (STUK) issued a statement to the Ministry of Employment and the Economy stating that Posiva’s encapsulation plant and final repository for spent nuclear fuel can be built to be safe.

Analysts estimate the cost for the repository’s entire life cycle, up to 100,000 years, at €3.5 billion.