The UK Atomic Energy Authority last week submitted its recommendation to the Government for dealing with the shaft full of radioactive debris at its Dounreay site in northern Scotland – the dirtiest decommissioning task facing Britain’s nuclear industry. It has previously been costed at anywhere between £200m and £500m.
The UKAEA had earlier narrowed the choice down to permanently sealing the shaft and its contents in situ or retrieving the contents for packaging and disposal elsewhere. In either case, the shaft and the surrounding rock could be frozen as an intermediate step to isolate it from the immediate environment.
While sealing in situ would probably be less expensive, coastal erosion at Dounreay may rule it out as a long-term solution. John Large, independent nuclear consultant, said: ‘The edge [of the coastline] is creeping towards the shaft.’