Public debate to progress nuclear waste options Jun 2020

For the nuclear power generating industry, used nuclear fuel can either be stored directly in a geologic repository or recycled to recover valuable materials.

Until recently, the construction of long-term deep geologic repositories has been the subject of much public debate. More recent advances demonstrate that long-term radioactive waste disposal practices are sustainable. Developments in Finland, Sweden and Canada show it is possible to make the technological and political decisions to move forward with geologic repository siting through constructive levels of public engagement with a potential host community.

Example of policy factors for long-term management of nuclear waste

Finland, Sweden and Canada are considered prime examples of engaging the public successfully on discussions about radioactive waste and final used fuel disposal. These public engagements are based on eight objectives of adaptability; community well-being; economic viability; environmental integrity; fairness; public health and safety; security; and worker health and safety.

In Finland, the effort surrounding disposal of high-level waste has been ongoing for decades, with the examination of four different sites taking place between 1993-2000. In 2001 a location had been selected, and excavation work for a deep underground rock characterisation and research facility began in 2004. In 2015, the Government of Finland issued the construction license for the final waste repository, with start of operations expected in the mid-2020s.

Entrance to Onkalo underground storage facility in Finland
Source: Posiva

The Onkalo site follows the Swedish disposal concept of of isolating the used fuel in copper placement canisters, covering the canisters with bentonite clay, and sealing the repository without the possibility of retrieving them once all waste placement activities are complete. The expected combined length of tunnels and shafts at Onkalo in Finland will total approximately 9.8km.

Sweden has not only managed to successfully engage the public on site selection for a final deep geologic repository, but also currently operates facilities for low and intermediate-level waste, comprising used protective clothing and replaced parts from power plants, and an interim storage of used nuclear fuel. This waste is deposited in rock vaults at the Forsmark facility, which was commissioned in 1988.

Sweden’s proposed final geologic repository, developed by the Swedish Nuclear Fuel and Waste Management Company, is based on three protective barriers. The used nuclear fuel is placed in copper canisters which are then placed in crystalline basement rock at a depth of about 500m and embedded in bentonite clay to prevent corrosion and act as a buffer. The total length of the tunnels at the proposed facility would be some 66km in which the repository occupies 3-4km² underground. Following emplacement of the used nuclear fuel canisters, the tunnels and rock caverns would be sealed permanently. Construction is expected to start in the mid-2020s with placement operations to begin about 10 years later.

Used fuel held in a pool at a Canadian nuclear power plant
Source: Canadian Nuclear Safety Commission

The technological approach for the proposed geological repository in Canada is to first store the used fuel bundles in wet storage at the reactor site for 5 to 10 years. Following this initial storage period, the fuel is placed into concrete and steel containers for interim storage by the power station operator under its operating license, until a permanent disposal facility has been sited, constructed, licensed and in operation. Interim storage methods provide sufficient shielding to safely store the used nuclear fuel without causing harm to the public or the environment. Since the early 2000s, the Nuclear Waste Management Organization of Canada has studied various approaches for final disposal of used nuclear fuel. Its efforts have brought about a distinctive option called Adaptive Phased Management, which is built upon citizen values, ethical principles and the eight objectives of adaptability; community well-being; economic viability; environmental integrity; fairness; public health and safety; security; and worker health and safety.

As part of its strategy, Canada proposes to develop and construct a deep geologic repository at between 500m to 1,000m deep in the stable Canadian Shield rock formation. The concept will involve the placement of CANDU fuel in specially designed containers below the water table and surrounded by bentonite clay. Unlike the Finnish and Swedish concepts, Canada proposes to design its storage capability with the potential for retrieving the waste. The capacity for retrieval is planned to be exercised until future generations have confidence in the waste storage system or determine other routes of waste management to explore based on future technologies.⁽²⁾ By 2023, Canada expects to narrow the list of interested possible host communities to determine a final site and to begin operation in the mid-2030s.⁽²⁾

Public debate for progress

For nuclear power to maintain its social license to operate, the technical and political decisions surrounding radioactive waste management must be resolved. Nations have access to sustainable practices, while public debates in host communities are leading to an increase of public acceptance for proposed radioactive waste management solutions. This is demonstrated in the successful public involvement for repository siting in Canada, Finland and Sweden, with their positive projected path towards completion.