A Decade In The Un-making - Decommissioning Dounreay

10th April 2018

Decommissioning a nuclear reactor is about more than removing the core itself and, around a decade after work started to pull apart a host of support facilities associated with Dounreay's oldest reactor, they have all gone.

Radioactive facilities, including a cooling pond, storage compound and examination cells assisted Dounreay Materials Test Reactor (DMTR) during its operational life. All have now been safely and painstakingly stripped out, culminating in the support building itself being removed from the landscape.

That final demolition included removal of a 27-tonne crane and several hundred pieces of cladding. Work to dismantle the inside of the structure saw remotely operated Brokks being deployed as well as a mobile crane which lifted 26-tonne shielded doors out through the roof.

Project Manager, Bill Lambie, said: "The final demolition of this complex is a significant achievement for all of those involved and represents a major step towards the ultimate removal of Scotland's oldest operational reactor. This was an area of the site with a highly radioactive inventory, large waste volumes and defunct plant and equipment.

"Now, due to the commitment and professionalism of the team, we have dealt with those hazards by applying innovation while keeping safety as the number one priority. This has been a team effort between Dounreay staff and a number of highly-experienced contractors including Nuvia, GDES, Matom and JGC Engineering."

The successful conclusion of this project leaves the reactor structure itself to be removed, with 5 companies bidding for the 3-year £7 million clean-up job. A contract is expected to be awarded later this year.

Bill added: "This is the first of three reactors that will be removed as part of the contract to decommission Dounreay. The knowledge, experience and skills gained by the team in the last decade will help other projects at the site as well as further afield."

DMTR was the first operational research reactor to achieve criticality in Scotland in May 1958. It had a thermal output of 25MWth and supported the site's fast reactor research programme, before closing in 1969.

Dounreay is Scotland's largest nuclear decommissioning project and is widely recognised as Europe’s most complex nuclear closure programme. The work is being delivered by Dounreay Site Restoration Limited, a company owned by Cavendish Dounreay Partnership, on behalf of the Nuclear Decommissioning Authority.

Mark Raffle, NDA Lead Programme Manager, Dounreay, said: “The removal of this significant support complex, which for many years played a key role in various site operations, is a clear demonstration of decommissioning progress on site. Its removal facilitates further work, including the removal of the DMTR."