In November, NRS used up to 700 kg of explosives to weaken four reinforced concrete plinths supporting two 65-tonne turbogenerators, the largest such use on a UK nuclear site and the longest programmed detonation sequence in Europe. High-reach cranes and excavators then cleared over 17,000 tonnes of concrete and rubble from the turbine hall, fire station, and electrical annexe. Approximately 35 miles of cable were also removed. The approach shortened the project timeline by four months, saved GBP300,000 (USD405,472), and reduced CO2 emissions by about 40 tonnes by minimizing machinery use.
The demolished materials were crushed, processed, and reused for ongoing construction projects, while a scrap metal contract generated over GBP3 million from 11,000 tonnes of metal, offsetting decommissioning costs. Sizewell A Site Director Alan Walker stated: “This is an incredible achievement for NRS, our contract partners Erith, the Office for Nuclear Regulation (ONR), and the Nuclear Decommissioning Authority (NDA).” He added: “The learning from this will be applied to other NRS projects to continue delivering efficient, value for money decommissioning and restoration of nuclear sites.”
NDA Programme Manager David Rushton said: “The successful demolition of the turbine hall brings skyline change to the Sizewell A site. The innovative use of explosives provides valuable learning for future decommissioning activities, and the segregation and reuse of demolition material supports the NDA’s sustainability targets.” ONR’s Nominated Site Inspector Andrew Bull noted: “We’ve worked very closely with NRS, adopting an enabling stance to allow the licensee to push forward with a modern, and at times, ground-breaking approach to accelerating this major dismantling project.”
Sizewell A’s two 210 MWe Magnox reactors operated from 1966 to 2006. Defuelling began in 2009, with all fuel transported to Sellafield by August 2014, rendering the site fuel-free by February 2015. The turbine hall demolition, approved in August, removed 99% of the site’s radioactive hazard. The cleared land will eventually be restored for reuse, with full site clearance expected by 2077.
