Syllabus Coverage: NFC5.1
Decommissioning of a nuclear facility at the end of its useful life involves the process of decontamination, dismantling and removal of all traces of radioactive material from the site in a safe, environmentally acceptable and economically viable way so that the site can eventually be returned to non-radioactive use. The non-radioactive use is the end-point of the decommissioning process:
- If the site is returned to a partially restricted use, it is termed a brownfield site
- If it is returned to completely unrestricted use, it is termed a greenfield site
Although decommissioning in general represents a reduced hazard when compared to the operational phase, there are specific problems associated with it. Whereas during the operational phase, plans and procedures flow smoothly, during the decommissioning phase there is a large element of unpredictability which arises due to the uncertainty regarding radioactivity — its nature, extent and composition. Consequently, decommissioning work needs to be carried out in a careful and structured way such that the doses and risks to the workers and the public are maintained As Low As Reasonably Practicable (ALARP).