The 100-kilowatt CONSORT reactor at Imperial College London's Silwood Park Campus in Berkshire began operations in 1965 and was shut down in 2012 due to increasing costs and a lack of research, educational, training and commercial use. Defueling was completed in 2014 and 31 fuel elements were removed and transported to Sellafield in Cumbria for interim storage pending reprocessing.
Imperial College applied to the Office for Nuclear Regulation (ONR) in January 2015 to begin a decommissioning project that would involve the removal of all radiological and non-radiological waste and the demolition of the reactor centre to enable the site to be de-licensed. The ONR granted consent for the decommissioning of the reactor in August 2015.
Decommissioning of the reactor and surrounding bioshield was completed in February 2020, and the demolition of all building structures, removal of the base slab and below ground services finished in April 2021.
How the former CONSORT reactor buiding appeared (Image: Imperial College London)
A year later, the ONR formally revoked the nuclear site licence of the Imperial College Reactor Centre (ICRC), saying it was satisfied that there was "no danger" and had "ceased to be any danger" from ionising radiation resulting from activities on the site.
ONR inspectors have studied the Silwood Park site's final Environmental Management Plan in recent months and are content that the concluding decommissioning work, including asbestos surveillance and landscaping, has been completed.
The Imperial centre is only the third UK reactor site in history to be fully decommissioned, and its land has now been returned for re-use.
"This is a highly significant achievement and milestone in UK nuclear decommissioning history and testament to all the hard work that has been put in at the Imperial College Reactor Centre to reach this final end state," said Ian Phillips, ONR's Head of Safety Regulation for Decommissioning, Fuel and Waste Sites. "It represents the conclusion of a 65-year journey for the ICRC which can now be recognised as the country's first ever fully decommissioned reactor site under modern regulatory controls - a fantastic accomplishment."
Trevor Chambers, former Head of the Imperial College Reactor Centre, added: "Imperial College London is indebted to the Reactor Centre team who provided deep technical and operational oversight throughout the project, as well as support contractors and the site Nuclear Safety Committee for their dedication.
"Releasing the site from regulatory control has created a recreational space at the heart of Imperial's Silwood Park eco-campus, which may now be used without restriction by staff and students at the forefront of biodiversity science and policy.
"Imperial continues to look to the future, with our Centre for Nuclear Engineering providing research and study opportunities to meet the world's growing energy needs while reducing carbon emissions."