Canada has been generating electricity from nuclear power for more than half a century. Used nuclear fuel is a by-product of this process.

What Is Used Nuclear Fuel?

Nuclear reactors in Canada are fuelled by natural uranium. The uranium is formed into ceramic pellets made from uranium dioxide powder and encased in zircaloy tubes called fuel pencils. These are welded together into bundles the shape of a fireplace log. Each bundle weighs approximately 24 kilograms. Each bundle is made of a strong, corrosion-resistant metal, called zircaloy.
This is an image of the components of a fuel bundle.

Canadian used nuclear fuel is not a liquid or a gas - it is a stable solid. Under Canadian and international regulations, it is not classified as flammable, explosive or fissile material.

Before being loaded into a reactor, the radiation hazards associated with unirradiated fuel bundles are relatively low. Radiation dose from unirradiated fuel bundles is about 0.05 mSv/h.This means the fuel can be safely handled without special equipment before it is used in the reactor.

When operational in a nuclear reactor, each fuel bundle can generate enough electricity to power up to 100 homes for a year. Once a nuclear fuel bundle has been used to generate electricity, it is removed from the reactor. Physically, the bundle looks the same as when it went in. However, it is now considered a waste product. It is radioactive and remains in this state for a long period of time. Used fuel must be contained and isolated from people and the environment – essentially indefinitely.

The NWMO has a legal obligation to provide long-term management of Canada’s used nuclear fuel. This includes the used fuel bundles that exist now, as well as those produced in the future.