When uranium was scarce, reprocessing was all the rage. Two decades on, the Cumbrian plant, though still a major source of jobs, has outlived its mission

Sellafield, former star of the nuclear age, scrubs up for a different future

Sellafield, former star of the nuclear age, scrubs up for a different future

Deep in the heart of Sellafield, Britain’s biggest nuclear waste site, a small piece of history is playing out. Technicians are about to use a huge amount of force to slice nuclear fuel into thin sheets, so that it can be dissolved in nitric acid, then chemically separated into uranium (for power stations), plutonium and highly radioactive waste.

But first they face a computer-says-no moment. Taut minutes pass as on-screen red boxes indicate issues with the shearing machine, which is safely ensconced behind a metre of leaded glass. Finally, the boxes turn green.

“Go for it,” says the operator, at which there’s a loud clanking, a white flash on a fuzzy video screen and smiles from staff crowded around.

This is the final shear at Sellafield’s thermal oxide reprocessing plant (Thorp), which has halted operations after 24 years it has spent reprocessing more than 9,000 tonnes of fuel from nuclear plants in the UK, Germany and Japan.

The facility – which in 2005 experienced one of Sellafield’s worst radioactive leaks – was built in an era of fears over uranium scarcity. Today, however, there is more than enough uranium globally to meet projected demand, so reprocessing no longer makes economic sense.

Facebook Twitter Pinterest Doors have been installed in a huge silo filled with nuclear waste Photograph: Michael Lishman/Sellafield

It is an emotional milestone for Thorp’s 450-plus staff, who are facing new, sometimes less prestigious roles, engaged in either winding up the plant or working on decommissioning of the wider site.

The scene also marks the start of the endgame for Sellafield, as its focus shifts to a decades-long mission of storing civil and military nuclear waste and gradually cleaning up the 700-hectare site.

The site, known to be the most hazardous industrial facility in Europe, dates back to the dawn of the nuclear age. This is where British scientists rushed to develop nuclear weapons during the cold war. The opening here of the world’s first nuclear power station in 1956 was billed as the start of a “new atomic age”.

Sellafield sits near Whitehaven on the West Cumbrian coast, cleaved in two by the river Calder. It is extremely congested – to the extent that more and more car parks are being shifted off-site to make space – and has no scope for expansion.

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Insiders often reach for the metaphor of 3D chess to describe the challenge of removing old and often contaminated infrastructure while building modern facilities to house waste the government hopes will one day be buried deep underground.

With 11,000 workers, Sellafield is like a town, with a laundry, hospital, restaurants and its own armed police to protect the stockpile of plutonium, the biggest in the world. The facility eats up two-thirds of the UK’s annual £3bn nuclear clean-up spending.

It was outsourced in recent years to a US-led consortium, whose performance was sharply criticised. Management has since returned to the public sector under the Nuclear Decommissioning Authority, but that has not stemmed criticism from MPs, who complained in October that Sellafield was nearly £1bn over budget and years behind on projects. The public accounts committee found signs of progress, however, and some are evident.

A building called “B30” is considered the most hazardous on the site – and by extension the most hazardous in Europe. It houses a concrete-walled pond open to the elements, and beneath its waters lie skips of waste fuel, dumped in haste half a century ago, and an unknown amount of radioactive sludge.

Photographs leaked four years ago showed how degraded the building, one of four such ponds, now was. There had been no plans to remove that waste for decades – but it has now started unexpectedly early, aided by remotely operated underwater vehicles – though these are contaminated in the process and become nuclear waste themselves.

The Observer witnessed only the second-ever batch being removed from B30, with a tractor allowed through a gate in the barbed wire-topped three-metre-high fence. Its load was a desk-sized metal box encasing a decades-old skip, probably filled with intermediate- or low-level waste. The hazardous cargo was trundled off to a modern shed, to be dealt with later.

Facebook Twitter Pinterest A crane dismantling a tower in the oldest corner of the Sellafield site

Elsewhere in this oldest corner of the site – which resembles a rundown industrial estate – is a US grain-style silo filled with nuclear waste. Huge metal doors have been fitted in its side to allow material to be mechanically removed – but retrieval work is not expected to start until next year.

Just metres away, a crane is bringing down an old tower, and workers are using a diamond saw to remove a seven-tonne block of concrete from the top of the building. David Peattie, the NDA’s chief executive, said: “The skyline is changing.”

The role the facility plays here in Cumbria is changing, too. With the recent collapse of plans to build a new nuclear power station in the field next door, Sellafield is a vital source of decent, high-paying jobs for the area. One anecdote shared – perhaps apocryphal – is of a local lawyer taking a job in the Sellafield laundry because it was better paid.

Tony Lywood, Labour’s prospective parliamentary candidate for Copeland, said even with no job losses, the end of reprocessing was a “disaster” for the area because of the changing nature of the work. He also opposes plans to see more future jobs in the private sector supply chain.

But Jamie Reed, a former Labour MP who quit two years ago to become head of community relations at Sellafield, said: “Our people have been brilliant. They understand Sellafield is changing. The mission is now clean-up.”

• This article was amended on 17 December 2019 to make clear the plutonium from Thorp is civilian grade, not military grade.