The UK’s Nuclear Restoration Services (NRS), a subsidiary of the Nuclear Decommissioning Authority (NDA) has selected infrastructure solutions company Costain for a deconstruction and height reduction project at the Trawsfynydd NPP in the Snowdonia National Park in North Wales.
The reactor buildings were built in the 1960s and have been subject to decommissioning works since 1991. The 392 MWe Magnox NPP at Trawsfynydd operated from 1965 to 1991. Defueling was completed by 1997. In 2020, NDA announced plans to accelerate Magnox reactor site decommissioning with Trawsfynydd identified as the ‘lead and learn’ site.
Costain’s in-house engineering team will work with NRS to support their safe and compliant decommissioning. The £70m ($94m) project, set to begin this autumn, is expected to take around four years. This will involve the deconstruction and partial reduction in the height of the power station’s two reactor buildings from approximately 54m to 25m, lessening their visual impact to local communities. The Trawsfynydd reactor buildings, originally designed by architect Sir Basil Spence, were a bold statement of mid-20th-century industrial design.
Costain will also deliver civil and remedial works to ensure that the buildings are in a safe and stable configuration for the start of subsequent decommissioning activity.
This is a pivotal moment for Trawsfynydd,” said NRS CEO Rob Fletcher. “After years of careful planning and preparation, we’re now moving into the delivery phase of one of the most complex and ambitious decommissioning projects in the UK. We’re delighted to be working with our supply chain partners to shape this next stage in the site’s journey, ensuring the work is undertaken safely, securely and sustainably for all our futures.”
NDA CEO David Peattie said: “This is a tangible step forward in one of the most significant projects in the NDA group’s portfolio and really embodies our commitment to delivering on a safer, cleaner future for generations to come. Reduction of the reactor buildings will not only advance our mission but also create first-of-its-kind opportunities for Wales, showcasing innovation and leadership in nuclear decommissioning.”
Sam White, Managing Director of Natural Resources at Costain, noted: “Whether it’s designing the infrastructure that will produce the next generation of advanced nuclear fuel, plant optimisation or managing large-scale decommissioning programmes, Costain has decades of experience delivering predictable, best-in class solutions across the entire nuclear energy lifecycle.”
He added: “This work is all part of creating a sustainable future, and we’re looking forward to deepening our relationship with NRS and working collaboratively with our local supply chain to complete this complex decommissioning project to the highest safety and quality standards.”
Costain previously delivered enabling works at Trawsfynydd to facilitate the decommissioning process, including the installation of a new capping roof on both the reactor buildings. It is also working with NRS (formerly Magnox) on a six-year decommissioning programme across 11 UK sites, and delivering decommission and asset care work for Sellafield as part of the Decommissioning Delivery Partnership.
The award marks Costain’s latest contract to deliver critically important infrastructure in the highly regulated nuclear energy sector. Earlier this year, Costain was selected to design Urenco’s new state-of-the-art advanced nuclear fuels production facility in Cheshire. It is also delivering a multi-million-pound framework to provide resourcing for the construction of Sizewell C.
