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| Decommissioning and Disposal |
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When a nuclear power stationcomes to the end of its useful life, decommissioning of the station commences with the aim of eventually returning the site to alternative uses with no nuclear legacy. Dismantling of the station takes place in stages, taking full account of public safety in containing the radioactivity at all times. The nuclear companies' "safestore" decommissioning strategy provides for reactor defuelling immediately after shutdown, taking 2-3 years and removing 99.9% of the residual radioactivity. Demolition of non-radioactive plant and buildings and dismantling of some radioactive plant is then undertaken. This is followed by the safe and secure maintenance of remaining structures for up to 135 years before final dismantling and site clearance.This ensures that radiation has fallen to a safe working level; it also reduces the amount of radioactive waste. In its Radioactive Waste Management Policy Review, the Government acknowledged the suitability of the safestore strategy. It required operators to submit their decommissioning proposals every five years for review by the Health and Safety Executive, in consultation with the Environment Agencies. Whilst recognising that the nuclear companies were in the process of making full provision for decommissioning in their accounts, the Review nevertheless required the establishment ofsegregated decommissioning funds for the privatised parts of the industry. The first commercial UK reactor to be closed for decommissioning was the Magnox station at Berkeley. Decommissioning work started in 1989 and is today still progressing to the care and maintenance stage. The Magnox stations at Trawsfynydd in Snowdonia and at Hunterston in Scotland are also being decommissioned; both have been defuelled and work is continuing in line with the safestore strategy. Minimising any adverse impacts onthe environment is a key objective throughout this work. |