HINKLEY C has hit its biggest milestone yet on schedule.

The completion of the base for the first reactor, known as “J-zero”, means that the construction of the nuclear buildings above ground can now begin in earnest.

The final 9,000m³ of concrete was the largest concrete pour in the UK, beating a record set by the Shard in London.

Reinforced with 5,000 tonnes of Welsh steel, the base has been under construction by the UK-French joint venture of Bouygues-Laing O’Rourke for six months.

The event was due to be marked by a visit from the minister responsible for nuclear energy, Andrew Stephenson MP, who visited the construction site today (Friday, June 28) and met apprentices at the National College for Nuclear.

EDF say good progress and efficiency improvements means the second Hinkley Point C reactor will hit its own J-zero moment in June 2020.

Contracts have been signed for an innovative collaboration to install the pipes and cables at the power station known as the MEH Joint Venture.

Pipework will be made by Bilfinger in Immingham at a modernised facility which will boost UK industrial capacity in this highly specialised area.

Hinkley Point C is working to tackle the UK skills shortage in welding by working with the MEH Joint Venture, ECITB, the Weldability Foundation, South West Institute of Technology and Bridgwater & Taunton College, to develop a new welding centre of excellence in Bridgwater.

Making use of EDF Energy’s £4.5 million investment at the college, the centre will train and qualify the UK’s next generation of welders, benefitting people and industries across the South-West.

The ambition is to provide 350-500 welding NVQ qualifications per year.

Innovation and the transfer of design, skills and experience from Hinkley Point C means the proposed near-identical project at Sizewell C can be significantly cheaper to build and finance, and that subsequent projects at Bradwell B and elsewhere will also benefit.

Almost 4,000 people are now working at Hinkley C, half of which are from the local area.

The world’s largest crane – the Sarens SGC 250 – is taking shape on site to allow prefabrication of large parts of the nuclear buildings.

Minister for Nuclear at the Department for Business Energy and Industrial Strategy, Andrew Stephenson said: “This is a huge achievement for Hinkley Point C and a major milestone for the UK’s nuclear new-build industry, which - as a low-carbon electricity source -is key to meeting our ambitious target of net zero emissions by 2050.

“The project will not only power nearly six million homes, it will add an enormous boost to the local and national economy, delivering over 25,000 new jobs and securing long-term, well-paid employment – a key step in delivering clean growth as part of our modern Industrial Strategy.”

Hinkley C managing director, Stuart Crooks said: “I am proud of the talent and achievement of our diverse UK workforce, our unions, our international supply chain and the design team in France.

EDF Energy CEO Simone Rossi said: “Hinkley Point C’s progress is good news for anyone concerned about the climate change crisis.

"Its reliable low carbon power will be essential for a future with no unabated coal and gas and an expansion of renewable power.

"The innovation at Hinkley Point C sets up the opportunity to reduce costs for consumers for a near identical power station at Sizewell C in Suffolk.”

MP for Bridgwater and West Somerset Ian Liddell-Grainger said: "When so many major engineering projects are beset with delays almost as a matter of course it’s hugely gratifying to see progress rolling on steadily at Hinkley – and the benefits to Bridgwater and the wider Somerset economy continuing to flow from the construction site."