Sellafield project reaches major milestone

The construction of a plutonium treatment plant has reached an important milestone as its roof was sealed with concrete.

The roof of the Sellafield Product and Residue Store Retreatment Plant (SRP), in Cumbria, has been sealed with a concrete pour meaning the building is watertight and can now be fitted with infrastructure and equipment.

The government said in January that the plant, when complete, would dispose of 140 tonnes of radioactive plutonium - currently stored at a secure facility at the site.

Sellafield said it aimed for the building, which was one of its "largest and most complex construction projects", to be in operation by 2029 until 2060.

The UK has the world's largest stockpile of the hazardous material, which is a product of nuclear fuel reprocessing.

It has been kept at the site and has been piling up for decades in a form that would allow it to be recycled into new nuclear fuel.

In January the government said it would put 140 tonnes of the hazardous material, currently stored at Sellafield in Cumbria, "beyond reach" making it ready for permanent disposal deep underground.

But the GMB union previously said plutonium should be considered "a national asset, not a liability".

Sellafield said the project would "play an essential role in managing the UK's plutonium stockpile".

The roof slab took 12 weeks to complete, with more than 2,700 cubic metres of concrete being poured and pumped to heights of up to 30m, a spokesman said.

"The Sellafield Product and Residue Store Retreatment Plant is one of our largest and most complex construction projects.

"Once operational, the plant will retreat and repackage existing material into more durable, long-term storage packages, ensuring they can be safely stored into the next century and beyond," the spokesman said.

Project director John Leslie said it was an "extremely complex major project to deliver" but he was "delighted we've reached another pivotal moment in the delivery of SRP".

Engineering apprentice Louis Twentyman said it was "amazing seeing it progress and to be part of it all – I can't wait to say I helped to build that".

"Not everyone gets to work on projects of this stature and where there's something interesting and exciting happening every day."

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