• Sources of nuclear waste
• Categories of nuclear waste
• Decommissioning
• Radiation and Radioactive Decay
• Managing Radioactive Waste Safely
• Responses to Managing Radioactive Waste Safely
• Responsibility for nuclear waste
• Disposal of nuclear waste
• Reprocessing spent fuel

Sources of nuclear waste
Nuclear waste comes from a number of different sources:

• the operation and decommissioning of nuclear power stations and fuel cycle plant
• nuclear research
• medical, industrial and other uses of radioisotopes.

Nuclear waste is disposed of according to its form and the level of its radioactivity.

Over 4 million cubic metres of waste are produced in the UK each year, of which only 1% is radioactive waste.


Categories of Nuclear Waste (See right hand column)

• Very Low Level Waste (VLLW)
• Low Level Waste (LLW)
• Intermediate Level Waste (ILW)
• High Level Waste (HLW)

Decommissioning
When they reach the end of their working lives, most nuclear facilities will be dismantled and their sites decontaminated. This is known as decommissioning. The decommissioning time for nuclear facilities varies considerably, from relatively short times to as long as 100 years or more.


Radiation and Radioactive Decay
Radioactivity decay of an isotope is measured as its 'half-life' characteristics. This is the time it takes for the isotope to lose half of its radioactivity. After one half-life the level of radioactivity is halved; after two half-lives it is reduced to a quarter; and so on.

To minimise risk when decommissioning first generation reactors, the strategy is to allow natural decay in radiation to a level where demolition workers can enter wearing standard protective clothing and use simple technologies.

However, in some circumstances, especially where alpha contamination is involved, delaying decommissioning can result in radioactivity levels actually increasing. In such cases, earlier action is prudent.



Managing Radioactive Waste Safely
The management of nuclear waste is the biggest single element in the cost of dealing with nuclear liabilities. Radioactive waste is the inevitable consequence of decommissioning and will require on-going management for at least a hundred years.

To address uncertainties about future requirements for safe radioactive waste management, the UK Government, with the devolved Administrations in Scotland, Wales and Northern Ireland, published a consultation paper in September 2001. This was entitled Managing Radioactive Waste Safely (MRWS). It set out a programme to review the options for management of solid radioactive waste and decide on a strategy for long term protection.

The period for consultation on the MRWS paper ended in July 2002. A summary of the responses can be accessed here.

Committee on Radioactive Waste Management
Following the Managing Radioactive Waste Safely consultation exercise, the Government concluded that a new committee should be established to review long-term options for the safe management of its radioactive wastes. The Committee on Radioactive Waste Management (CoRWM), which is chaired by Dr. Katherine Bryan, is expected to make recommendations to Ministers in 2006. It will then be for Ministers to decide which options to adopt for the long-term management of radioactive waste.

Responsibility for nuclear waste
The UK takes its responsibilities towards protecting health and the environment very seriously. All radioactive discharges from the UK are controlled by the environment agencies.

Overall policy for radioactive waste management is the responsibility of the Department for Environment, Food and Rural Affairs (DEFRA) and the devolved administrations. Further information can be obtained from visiting the DEFRA web site. Other Departments such as the Department of Health (Food Standards Agency) and the Ministry of Defence also have a close interest, as does the Health and Safety Executive (HSE) and the Environment Agency (HA).


Disposal of nuclear waste
The UK currently disposes of most low level wastes, mainly to the Drigg surface disposal facility in Cumbria.

Until 1982, the UK disposed of some low and intermediate-level wastes in drums at selected sites in the deep ocean. This was discontinued and in 1993 the Government accepted an international ban on disposal of radioactive wastes at sea.

In its 1995 policy statement on management of long-lived low and intermediate (but not high) level wastes, the Government gave UK Nirex the task of developing a deep underground disposal facility. This would isolate the waste from the environment while its radioactivity decayed to safe levels.

Nirex carried out detailed surface geological studies in the vicinity of Sellafield. In 1997, it was refused planning permission for a Rock Characterisation Facility to examine the geological strata in which to construct the disposal facility. Long term policy on management of these wastes is consequently being addressed in MRWS.


Reprocessing
Reprocessing spent fuel recovers potentially re-usable uranium and plutonium and separates out the very small amount of waste. Spent fuel in itself is not a nuclear waste. Owners of spent fuel can choose to reprocess the fuel or to seek alternative management options, though to date no one has disposed of spent fuel. There is currently no technically proven alternative to reprocessing Magnox fuel.


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