Waste management in the nuclear industry

 

Key Points

  • Many industries produce waste of various kinds and most discharge these wastes directly into the environment. The uranium and nuclear industries contain their wastes to their own sites (either mines or nuclear power plants)
  • Management of tailings (mine waste) at uranium mines isolates the material from the surrounding environment and contains the waste on the mine site.
  • The Australian uranium industry applies world’s best practice in designing and building tailings storage facilities and continually improves its knowledge and practice in this area
  • Nuclear power is characterised by the very large amount of energy available from a very small amount of fuel. The amount of waste is small and is carefully managed
  • Each country which uses uranium to generate power takes responsibility for managing resulting waste
  • The establishment of facilities for the storage of high-level and intermediate – level nuclear waste is a significant challenge, in which political rather than technological issues are the main hurdles
  • Above-ground storage of spent fuel is a safe technology which is used at many nuclear reactor sites
  • The world’s first site for deep underground storage of high-level reactor waste is likely to be established at Forsmark in Sweden, with the first contained waste expected to be packed in impermeable clay 500 metres underground from 2023

The waste management context

The uranium mining and nuclear energy industries have identified the potential risks from their waste or spent fuel by-products and minimise these risks by applying their special knowledge and resources to manage the waste materials themselves.

The uranium mining industry, like all mining sectors, contains and stores on its own sites the waste rock and mining and processing fluids it produces in extracting uranium ore.

The uranium industry applies world’s best practice in the construction and management of tailings storage facilities.

The nuclear energy industry safely stores and manages hot and radioactive spent fuel from reactors, usually on the sites of the nuclear power stations themselves.

(see also Issues Briefing: Managing uranium mine waste )

Wastes from using uranium in nuclear reactors

Highly radioactive wastes are created when uranium is used in a reactor. 

About 25 tonnes of used fuel is taken each year from the core of a l000 MWe nuclear reactor. Only a small amount of the original uranium will have been ‘burned’, but the fuel is contaminated with by-products that severely reduce the efficiency of the reactor. In some cases, despite the remaining useful fuel, the ‘spent’ fuel is regarded entirely as waste (as in USA and Canada) and is stored for later permanent disposal. In other cases, the spent fuel is regarded as a useful resource and is reprocessed (as in Europe and Japan). 

Many nuclear scientists and nuclear industry managers now tend to regard the spent fuel waste - which contains significant amounts of unused fuel - as an asset which will be used in newer generation reactors as a key fuel source.

These scientists, enigneers and managers argue that this future use of unused fuel will greatly reduce the volume and the time requirement for storage of the spent fuel waste now being produced by current-generation reactors.

Whichever current option is chosen, and whichever way you regard and plan for management of current waste,  the used fuel is first stored for several years under water in large cooling ponds at the reactor site. The concrete ponds and the water in them provide radiation protection, while removing the heat generated during radioactive decay. 

In many cases, once the spent fuel has cooled and its radioactivity has declined, the material is transferred to metal- and concrete-shielded casks around 6 metres high which are then stored above ground on the power station site.

This is a safe method of long-term storage which requires appropriate security protection.

Only now (i.e. as some nuclear power stations are nearing the end of their operational lives) is the permanent disposal of nuclear waste becoming an issue.

Technological challenges have been largely overcome, with the scientific consensus favouring immobilisation of the waste and permanent underground disposal in stable and impermeable geological structures.

Political issues relating to the location of such repositories remain in many countries. Sweden has largely resolved these issues and has selected a location, Forsmark, for its repository, which is likely to begin receiving high-level waste for permanent disposal from 2023.

For further information on nuclear waste management and disposal, the World Nuclear Association’s briefing on the subject or visit the International Atomic Energy Agency website where information is provided on a number of pages.

May 2010