Explosions used to speed up demolition at Sizewell A

The twin reactors at Sizewell A were shut down on at the end of 2006 after 40 years of electricity generation and planning permission granted to demolish the turbine hall and electrical annexe. 

The explosion, carried out by Precision Demolition Company Ltd, is the biggest ever on a licensed UK nuclear site. 

A series of test blasts were undertaken as well and the detonator timing sequence was designed to meet nuclear site requirements for air overpressure and ground vibration. 

And because of this workers will be able to raze it to the ground within two weeks - rather than months.

Those behind the blast say the explosion has made "significant efficiency savings" by reducing the time and money needed on the project, as well reduce prolonged periods of air pollution.

Credit for video: Nuclear Restoration Services

Alan Walker, Sizewell A site director, said: "It’s fantastic to see Nuclear Restoration Services (NRS), our contract partners and regulator, The Office for Nuclear Regulation, 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.”

Also part of the project was the Office for Nuclear Regulation (ONR) who oversaw the explosion. 

The work was one of the largest programmes at Sizewell A in recent years, with more than 7,000 tonnes of metal removed and recycled from the turbine hall in the lead-up to the detonation.

John Wolstenholme, ONR's specialist civil engineering inspector, who leads on demolition and explosives, said he hopes the work can be used to "accelerate demolition on the rest of the UK’s decommissioning nuclear licensed sites".

Part of the process to the demolition of Sizewell A (Image: Nuclear Restoration Services)

The rubble after the explosives to the Sizewell A site (Image: Nuclear Restoration Services)