Finnish nuclear waste management company Posiva Oy and construction company YIT Rakennus Oy have signed a contract for an excavation project at the Onkalo underground bedrock research facility in Olkiluoto.

Onkalo is being used for research and testing activities related to the planned construction and use of a final disposal facility for used nuclear fuel.

Posiva did not reveal the value of the contract, but said it covers excavation of an access tunnel to the area where the final disposal of the fuel will take place, and excavation of a maintenance and parking garage some 430-440 metres below ground. Rock sealing and reinforcement work is also covered by the contract.

Work is scheduled to begin in March 2016 and take 10 months. The final disposal at Onkalo of used fuel from the Olkiluoto and Loviisa NPPs is scheduled to start in the early 2020s, Posiva said.