Spent fuel is the name given to nuclear fuel that has been removed from a nuclear power or research reactor following irradiation. It is a mixture of plutonium, uranium and waste materials and is no longer usable as fuel. It is extremely radioactive and generates a large amount of heat and must be carefully managed. Individual Member States take different approaches to the long-term management of spent fuel, but all involve a period of interim storage at the nuclear power plant or research reactor site following the removal of the fuel from the reactor.
The spent fuel may be stored in a facility containing air or an inert gas (dry storage) or under water or other liquid (wet storage) depending on the composition of the fuel. Wet storage is by far the most common interim storage method. Following interim storage there are two principal approaches to the long term-management of spent fuel.
Direct disposal involves the packaging of the spent fuel following which it is transferred to a permanent disposal facility. Reprocessing involves the separation out of the plutonium and/or uranium from the spent fuel to allow for its reuse in new nuclear fuel or for other purposes. The other radioactive materials remaining following reprocessing are highly radioactive and long-lived and may also require conditioning prior to permanent disposal in a dedicated facility.
Currently five Member States use the reprocessing option and two Member States are actively pursuing the direct disposal option. In the majority of Member States a definitive spent fuel policy is not yet in place, other than arrangements to ensure a safe extended period of storage for 50 to 100 years. Information on the policy in individual member states is available in the country profiles.