Chapelcross power station was Scotland’s first commercial nuclear facility. The station opened in 1959 and became the mainstay of electricity production in South West Scotland.
After 45 years of successful operation the reactors were switched off in 2004. During 2007, the four cooling towers will be explosively demolished, removing a significant feature of the Dumfriesshire skyline.
The decommissioning of Chapelcross will be an important milestone in the closure of more than 20 elderly nuclear power stations in Britain. Nuclear energy provides 19% of the country’s electricity which will fall to 6% as old plants cease generation. But this is not the end of the nuclear story. In a 216-page review called The Energy Challenge published on 11 July, the British Government has introduced a range of measures to cope with the forecast energy crisis. So what are the British going to focus on? They propose a mixed approach to energy saving and supply including the building of new nuclear stations.
Chapelcross power station
Like the Pantheon in Rome, you can only see the sky above, when inside one of the 85 metres high cooling towers. Here, Site Manager Mike Travis. (Photo: Nina Eirin Rangøy)
Return to green fields Standing in the middle of a cooling tower is a strange experience. A huge cavern, 85-metres high and made of solid concrete, with a giant circular opening at the top. Like the Pantheon in Rome, you can only see the sky above. And where there were previously huge clouds of steam from the cooling process, there is now emptiness. From being a power generating unit with a capacity of 200 MW, the nuclear power station at Chapelcross is now a complex demolition project whose end goal is to return the site to green fields. Chapelcross is a major employer in the region and local people value its contribution to the community. The cooling towers have been an iconic landmark on the horizon for nearly 50 years and many will be sad to see them go.
Safe decommissioning Although nuclear power is experiencing a renaissance, it is critical that the decommissioning of older power stations is carried out safely – both for the community and for more than 400 production workers that are being retrained as project employees and decommissioning specialists.
Mike Travis, has been the site manager at the Chapelcross power station since it ceased generation in 2004: “The closure and decommissioning of a nuclear power station is very demanding and involves numerous challenges. Safety is a very strong and natural part of our culture so we are ready for the challenges ahead. Radioactivity is still a hazard but there are now many new ‘dangers’ we have to look out for. We’re now a building site in reverse.
Instead of building a power station we are going to demolish one – and that may be more dangerous than either building or operating such a station.”
Proud of our performance DNV has been hired to assess the safety, environmental and business performance at 11 British Nuclear Group facilities. The assessments use ISRS – DNV’s world leading system for measuring, improving and demonstrating management system performance. British Nuclear Group, Chapelcross is the first site in the world to have an ISRS award level assessment.
“We’re all proud and pleased to be awarded a Level 7, in the first level assessment that has been performed with this new version ISRS 7th Edition,” says Andy Feltham, the environment, health, safety and quality manager at the Chapelcross power station. “An important challenge for us is to simplify our work processes without compromising safety. The ISRS assessment has been helpful in exploring how this can be achieved, with its thorough process involving more than 50 site personnel. The DNV team helped us identify our strengths and highlight areas for improvement.”
99% will be reused The team at Chapelcross gives priority to major hazards first. This means the removal of 400 tonnes of spent nuclear fuel that is still contained in the four nuclear reactors. This spent nuclear fuel will be transported to the Sellafield nuclear facility a few miles over the border in England. The nuclear fuel will be recycled there – and 99% will be reused, while the last 1% will be isolated and stored securely for several centuries. This work is expected to be completed in 2009. In just over 20 years, the entire power station area will then be decommissioned in accordance with the strategy of the Nuclear Decommissioning Authority, the organisation responsible for managing this process across the UK.
Chapelcross will conduct another ISRS assessment once the defuelling has been completed, to help them prepare for decomissioning. In the meantime, Mike Travis and his team will use DNV to help develop systems for managing business risk. “What can hurt us as a unit? What can stop us? What commercial risks are we running? We need a methodical, high level look at what can hurt us in the future,” says Mike Travis, who is in charge of the annual budget of GBP 70 million.
Safer and more efficient The Chapelcross power station has come to the end of its operational life, but the world needs more and more energy. Nuclear power is experiencing renewed popularity throughout most of the world. New power stations are going to be built. They will be built to the highest safety standards, more efficient and ten times as productive as the first power stations built in the 1950s.
Date: 2006-08-25 Author: Harald Bråthen Source: DNV Forum no. 2, 2006