The Vulcan Nuclear Reactor Test Establishment at Dounreay. Photo credit: John832 Wikimapia
The Royal Navy's nuclear submarine test reactor at the Vulcan site at Dounreay has been shut down for the final time, paving the way towards defuelling and decommissioning of the site.
The Vulcan Naval Reactor Test Establishment at Dounreay, Caithness, has tested nuclear submarine reactors since the 1950s to help in evaluating reactor performance and prediction of problems with reactor design.
Recent test work at Vulcan has focused on the 'Core H' PWR2 pressurised water reactor design which powers the Navy's Vanguard and Astute class submarines. Vulcan's PWR2 reactor was shut down for the last time in July 2015 and will now be defuelled, with spent reactor fuel transported by train to the Sellafield nuclear reprocessing plant.
In November 2011 Defence Minister Peter Luff announced in a written Parliamentary statement that no future use was foreseen for the Vulcan facility following a decision to design and develop future submarine reactors purely on the basis of computer modelling, analogy from existing reactor designs, and testing of individual components and systems.
Decommissioning will now take place at Vulcan over the next seven years. In 2005, the MoD estimated that it would cost £2.1bn to decommission Vulcan and decontaminate and deal with waste at the site.
The Ministry of Defence (MoD) expects to make a final decision on options for the longer term future of the site in 2016 as part of its Vulcan Defuel and Decommissioning (VDAD) programme.
The PWR2 test reactor at Vulcan was the subject of controversy in 2014 after the government revealed that low levels of radioactivity had been found in its cooling system. The problem was first discovered in 2012 but had been covered up until 2014. As a result of the problems Trident submarine HMS Vanguard will receive an unplanned second refit and reactor refuelling at a cost of £120 million, and contingency measures will be required to safeguard other Vanguard and Astute class submarines.
An earlier first generation PWR1 test reactor at Vulcan was shut down in 1987 and is currently under a 'care and maintenance' regime awaiting decommissioning.
Despite the PWR2 reactor shut down the Vulcan site will remain open, and experience from decommissioning work will continue to support the Royal Navy's submarine programme. MoD has said that the majority of the existing workforce will work on clean-up operations and will retain their jobs.
Rolls-Royce, who have designed the Navy's PWR reactors and operate the Vulcan site, has said that the site has “high-value work to 2030 and beyond” and that there will be a need to retain a skilled workforce at around existing levels until then. The company is developing a business plan for the workforce over the longer term.