Finland’s Posiva, Sweden’s Svensk Kärnbränslehantering (SKB) and Canada’s Nuclear Waste Management Organisation have collaborated on a five-year, (2008-2013) research project, The Greenland Analogue Project (GAP), investigating ice sheet conditions, in relation to the long-term management of used nuclear fuel in a deep geological repository. The focus of the study, the Greenland Ice Sheet, is the second largest ice sheet in the world and comparable to the ice sheets predicted to extend over both Scandinavia and Canada in the future.
The research, described in a report, focuses on increasing scientific understanding of how an ice sheet interacts with areas both above and below ground. This can be used in comprehensive, detailed studies used to evaluate the safety of deep geological repositories over timeframes of up to a million years. During the last million years, regions of Finland, Sweden and Canada have experienced multiple ice ages, occurring on average every 100,000 years. “That is why it is imperative to understand the conditions at the surface and below an ice sheet when planning for the management of used nuclear fuel in a deep geological repository,” the companies said. The research, carried out in western Greenland, close to Kangerlussuaq town, involved direct and indirect observations of ice sheet movement, meltwater runoff, water pressure due to the weight of the sheet, and water transfer from the ice sheet to areas below the ice surface. Boreholes were drilled through the ice sheet to the point of contact with the underlying rock to measure the underground pressure exerted by the ice sheet. A borehole was also drilled at the edge of the sheet at a depth approximating repository conditions to enable hydraulic and chemical monitoring to be carried out. Weather stations monitored climate conditions.
SKB's application for an integrated system for the final disposal of used nuclear fuel and radioactive waste received approval from the Sweden’s Radiation Safety Authority earlier in 2016. Posiva last year received a licence from the Finnish government to construct an encapsulation plant and final repository for used fuel at Olkiluoto. NWMO is conducting a phased process to identify a site for a deep repository for Canada's used nuclear fuel.