Uranium arrives at a nuclear power plant in the form of pellets which are

bundled together to form a fuel assembly. When the assembly no longer produces enough

energy, the pellets are replaced. The used-up pellets are called 'spent-fuel'.

Spent fuel is highly radioactive and needs to be isolated from people and the enviroment

for around 10 000 years. After this time the radiation level has reduced and the waste is

considered safe. Spent fuel is usually contained in concrete or steel containers, or in

cooling pools.

Spent fuel can be reprocessed to extract and recycle Uranium and plutonium. Great

Britain, France, Japan and Germany currently reprocess some of their nuclear waste.

To gain a more thorough overview of sources of pollution and their comparative amounts,

other sources of enviromnental pollution such as
href=/graph/env_pol_car_dio_fro_fos_fue_200>Carbon dioxide,
href=/graph/env_pol_sul_oxi_per_cap>Sulfur and
href=/graph/env_pol_nit_oxi_per_cap>nitrogen oxides should also be consulted.