A significant milestone at Sellafield

The first UK power reactor has reached a significant milestone as the unique golf ball design reactor comes to the end of its 20 years of decommissioning.


A significant milestone has been reached as the well known iconic landmark with its unique golf ball design at Sellafield has completed its last campaign to decommission the facility.

The final section of the Outer Ventilation Membrane (OVM) was safely removed from the reactor’s concrete bioshield at the end of May, marking the successful completion of the final reactor decommissioning campaign.

Ian Cowan, WAGR project manager said: “Completion of Campaign 10 is a significant milestone for the WAGR Decommissioning project and draws to a close twenty years of work to safely dismantle, process and place into passive storage an industrial scale power generating nuclear reactor”.


The Windscale Advanced Gas Cooled Reactor (WAGR) was built in the early 1960’s to serve as a test bed for further development of advance fuel and other components and to provide operational experience of power production and was the forerunner to the UK’s second generation of power reactors. It was owned and operated by the United Kingdom Atomic Energy Authority (UKAEA) and later by Babcock International Group plc which, up until January 2011, managed the decommissioning project.

Chris Halliwell, head of Programme Delivery Sellafield remediation and Decommissioning Projects/Windscale said: "This is a fantastic achievement and the culmination of many years’ work from Sellafield Ltd, UKAEA and its subcontractors.
“It is a true demonstration of the UK's ability to fully decommission nuclear power stations in a safe, sustainable and cost effective manner, and it augurs well for the decommissioning of other high-hazard facilities on the Sellafield site."

Dr Ian Hudson, NDA head of Programme for Sellafield said. "As we progress the clean up mission it is important that major milestones such as the successful completion of this campaign are achieved as soon as practically possible, and that we maximise our expertise to improve performance. Maintaining momentum on lengthy programmes is equally important and again reflected in the successful conclusion of this phase of the decommissioning of WAGR."

In anticipation of the UK’s likely nuclear decommissioning needs the United Kingdom Atomic Energy Authority (UKAEA) decided in 1981 to decommission WAGR as the national demonstration exercise for power reactor decommissioning.

The first years of the decommissioning project were spent designing the necessary components, modifying the structure and installing the equipment but in 1999 it was decided that the dismantling of the reactor core and pressure vessel should begin after the project team had completed all testing of the principle methodology to remotely dismantle the components.

The decommissioning campaigns 1 to 6 were complete by 2002 with the reminder of the campaigns being progressed up until Campaign 10, the outer ventilation membrane and thermal columns which were decommissioned in May of this year.

This invaluable knowledge of dismantling and decommissioning skills, will be used in other high-hazard reduction projects across the Sellafield site and the wider nuclear industry.

Peter Law, Windscale senior project manager, added: “The WAGR project team should be immensely proud of their achievements. Completion of the reactor dismantling has required a great deal of technical ingenuity and persistence and has proven the decommissioning of power reactors soon after shutdown can be safely achieved with currently available technology.”

Source: Sellafield Ltd.