Posiva Oy, the company responsible for the disposal of Finland’s spent nuclear fuel, announced last week that it has begun excavating the first disposal tunnels at the Onkalo deep geologic repository near the Olkiluoto nuclear power plant.

Onkalo, Finland’s deep geologic repository for spent nuclear fuel, has been characterized as a game changer for the long-term sustainability of nuclear energy by Rafael Mariano Grossi, director general of the International Atomic Energy Agency.

“Finland has had the determination to move forward with the project and to bring it to fruition,” Grossi said during a November 26 visit to Olkiluoto, Finland, where the repository is under construction. “Waste management has always been at the center of many debates about nuclear energy and the sustainability of nuclear activity around the world. Everybody knew of the idea of a geological repository for high-level radioactive nuclear waste, but Finland did it.”

Posiva Oy, the Finnish company tasked with researching and creating a method for the permanent disposal of spent fuel from Finland’s Olkiluoto and Loviisa nuclear power plants, obtained a license to construct the Onkalo repository in 2015, marking the first time that a construction license for a geological disposal facility was issued anywhere in the world. The site near the Olkiluoto plant was chosen following several years of screening a number of potential sites.

Finnish energy company Fortum Power and Heat Oy has initiated an environmental impact assessment procedure for the two reactors at its Loviisa nuclear power plant with the aim of operating the units for 20 years beyond their current license expiration dates of 2027 (for Unit 1) and 2030 (for Unit 2).