Sizewell A delivers groundbreaking turbine hall milestone

Over 700kg of explosives have been used in the first stage demolition of four gigantic concrete plinths as part of work to decommission the turbine hall.

This significant achievement sets a new record for the largest use of explosives on a nuclear site for conventional demolition purposes in decades.

Over 1,200 holes were drilled into the plinth structures that bore the weight of two turbo generator units weighing 605 tonnes each. The charges were then set and the plinths wrapped ready for detonation. This method reduced the need for heavy machinery – saving time, cost, reducing noise and dust levels.

Alan Walker, Sizewell A Site Director, commented: “It’s fantastic to see Nuclear Restoration Services (NRS), our contract partners and the Office for Nuclear Regulation (ONR) pushing the boundaries of innovation in de-plant and conventional demolition together.

“The detailed planning and stakeholder engagement for this were exemplary. Everyone involved has done an outstanding job and this success demonstrates our commitment to achieving safe, efficient decommissioning processes.”

The ONR strictly governed the use of explosives. Their presence and oversight gave confidence that every aspect of the set up and execution had been thoroughly checked to ensure maximum safety.

Andrew Bull, ONR’s Nominated Site Inspector at Sizewell A, said: “This was a great example of joint working between regulator and dutyholder and everybody being open to considering and actioning novel and forward-thinking technological solutions to bring about efficiencies.

“ONR’s stance as a consistently enabling regulator means that we will always support proactive and innovative methods of working provided these are conducted safely and securely.”

Large machinery has now removed the weakened material, taking this significant demolition project a huge step forward.

NDA Group Chief Assurance and Performance Officer, Alan Cumming, visited the site this week to see the progress being made and meet the teams involved. He said:

“This is what mission delivery is all about. Decommissioning, knocking stuff down and dispatching the waste. It’s an incredible achievement and testament to the expertise, capability and innovative mindset each partner brought to the project.

“It showcases the power of collaboration and our capability as a sector to deliver groundbreaking progress, while still maintaining the most rigorous safety standards, paving the way for future advancements.

“This is a substantial step towards completion of the safe, secure and sustainable decommissioning of Sizewell A, leaving a positive legacy for the community and future generations.”

Over 7,100 tonnes of metal have been removed – that’s more than three London Eyes. This is being recycled and sold on the metals market to generate income. Over 17,000 tonnes of demolition rubble will also be re-used and recycled.

The overall turbine hall structure is expected to be demolished in Spring 2025 creating a footprint the size of a large football pitch. This land will eventually be restored and released for re-use.

It follows the sale of 1.2 hectares of land on the site transferred to EDF Nuclear Generation Limited (ENGL) earlier this year. This delivered on a multitude of NDA and NRS strategic objectives - marking tangible progress in the completion of the decommissioning mission and delivering benefit to the local community and the wider economy.