Chernobyl's new sarcophagus took two decades to make. Bigger than Wembley Stadium and taller than the Statue of Liberty, it will seal in the entire disaster site for 100 years.

World leaders jostle with global executives and anonymous men dressed in full camouflage as platters of shrimp, foie gras and cheesecake are passed around by white-gloved staff. It would all seem quite normal were it not for the fact that we’re just 100m (330ft) away from the site of the worst nuclear disaster in history.

Chernobyl's renewal

Check out a photo gallery of life inside the exclusion zone

With the damaged reactor now newly confined, the site of the worst nuclear disaster in history faces a better future. Ukrainian photographer Anton Skyba visited Chernobyl last year to document the gradual renewal of a site that has remained desolate for 30 years.

Take a look at his photos here.

A hospitality tent has been erected just inside the gates of the Chernobyl nuclear power plant near Pripyat in Ukraine. The tent has many windows, to ensure everyone gets a good view of what’s about to happen.

These guests are here to witness the final stage of a 30-year clean-up job that has been underway, on and off, since one of the plant’s reactors exploded in 1986. The Chernobyl disaster still casts a pall over nuclear power. And other serious accidents, such as that at Fukushima in Japan in 2011 – the only other incident to be classified a maximum Level 7 in the seven-point International Nuclear Event Scale – are weighed against it.

It also set in train a series of measures to ensure nuclear safety around the world. Now the whole site is about to be encased inside a vast structure known as the sarcophagus, sealing in some of the most dangerous waste material in the world for at least 100 years.

The project has been more than two decades in the making. One of the distinguished guests is Vince Novak, the Director of Nuclear Safety at the European Bank of Reconstruction and Development. Novak was in his 30s when the accident happened. Now in his late 60s, he is here to watch his life’s work literally slide into place.

The behemoth 35,000 tonne structure beside us has spent the past few days inching along a set of purpose built tracks towards its final destination. This sarcophagus – or New Safe Confinement (NSC) – is taller than the Statue of Liberty and larger than Wembley stadium. But what it resembles most is a very large metal shed.

The sarcophagus is the largest object people have ever moved

Its appearance belies its historic importance, however. The NSC is not only the largest object people have ever moved, it’s also a symbol of what we can achieve when the stakes are highest.

It is hoped the sarcophagus will draw a line under this catastrophic chapter in the history of nuclear energy. Yet when the idea of building a vast structure at Chernobyl’s ground zero – where radiation levels are still hazardous – was first put forward in the 90s, people thought it was crazy.

It’s far from the strangest suggestion Novak has heard, however. In his years on the project, he’s received thousands of far-fetched pitches. “The craziest proposal I’ve heard actually came just a few days ago,” says Novak. “A Russian scientist emailed us and suggested that he could outline how to rebuild the plant.”

Watch a rapid timelapse of the structure's growth, in five seconds. (Credit: Novarka)

That’s not going to happen. On 26 April 1986, the fourth reactor at the Chernobyl nuclear power plant exploded during a routine stress test. A fire raged for nine days. The steel and concrete containment shell collapsed and the super-heated fuel melted through the floors into the basement beneath. The exposed, burning reactor spewed radioactive isotopes into the atmosphere. The fallout reached across Europe as far as Scandinavia – but the worst hit regions were in Ukraine, Belarus and Russia.

Shortly after the accident, Hans Blix was flown to Chernobyl. Blix would later become better known for chairing the United Nations commission responsible for disarming Iraq of its weapons of mass destruction in the run up to the 2003 war. But at that time he was the director general of the International Atomic Energy Agency, based in Vienna, Austria. He was one of the first non-Soviet officials allowed to see Chernobyl after the accident.

I never could have envisioned this structure at that time – Hans Blix

“I never could have envisioned this structure at that time,” Blix told me as we stood beside the new sarcophagus. “I was flown over the site in a helicopter and my only thought was ‘What a horrible tragedy.’ Here was this black smoke coming up from the graphite that was burning, and I needed to figure out what we at the IAEA could do.”

Many leaders were unwilling to believe the official reports coming from the Soviet government, which wanted to protect the reputation of its nuclear energy programme. Blix knew that his organisation had to become the key source of objective information. As he took the stage in Moscow to inform the world about the scale of the disaster, his team began to assemble the technical experts that could figure out what to do next.

In the meantime, the Soviets were sending scores of people – many ill-equipped and poorly trained – to carry out an emergency clean-up. The first team was instructed to bring the fires around the nuclear plant under control. It took them nine days and at least 28 people are known to have died as a result of exposure to radiation during that time.

These men and women came to be known across the Soviet Union as “the liquidators”. Last year, I spent two days with a group of liquidators from western Ukraine who had travelled to Chernobyl to commemorate the 30th anniversary of their time here.

It took a nightmarish 206 days to build the first sarcophagus

They were serving as firefighters in the town of Ivano Frankivsk – around 600km (370 miles) away – when the accident happened and they received notices to report to Chernobyl. None of them had any idea what they were really going into. The group I spoke to said they worked on deactivating the third and fourth reactors. They then helped build the structure that has contained the worst of the radiation until now.

It took a nightmarish 206 days to build that first sarcophagus, using 400,000 cubic metres of concrete and 7,300 tonnes of metal framework. "We worked in three shifts, but only for five to seven minutes at a time because of the danger,” the group’s leader, Yaroslav Melnik, told me. “After finishing, we'd throw our clothes in the garbage.”

In total, around a million men and women from across the Soviet Union were brought in to help with the initial clean-up and containment. Helicopters flew over the reactor dropping sand, lead and other substances to extinguish the fire and prevent radiation from escaping. Coal miners dug underneath the reactor’s core so that liquid nitrogen could be pumped in to cool the nuclear fuel.

Others removed contaminated materials and evacuated civilians. Reports differ but some suggest that thousands of these liquidators died during their work. The consensus is that most of them suffered horrific long-term illnesses from acute radiation exposure.

Despite the heroic efforts of the liquidators, that first sarcophagus was never meant to last and a long-term solution was still needed. Yet until the Soviet Union collapsed in 1991, the true situation at the site remained unclear. In the ensuing chaos, the International Atomic Energy Agency quickly commissioned a project to learn all it could about Soviet-designed reactors.

This became the technical basis from which the rest of the world would address the problem. A few months after the Soviet flag lowered over the Kremlin for the last time, Ukraine launched an international competition for ideas about how to make Chernobyl safe again.

Until the Soviet Union collapsed in 1991, the true situation at Chernobyl remained unclear

The call was won by a French consortium with a plan called “Resolution”, which involved encasing the entire Soviet-built sarcophagus with the damaged reactor inside it within a whole new structure. But the checklist for such an edifice was daunting.

It would have to be enormous. It would have to last for at least 100 years. And it would have to be built on the doorstep of a highly radioactive site without risking the safety of the workers – and then moved to its final position, further than anything that big had ever been moved before.

A decade after the disaster, things finally got going. In June 1997, the leaders of the G7 met in Denver and agreed to put $300 million into the project. Several months later, American Vice President Al Gore, Ukrainian President Leonid Kuchma and the President of the European Bank for Reconstruction and Development met in New York City for a formal handover of the money. “That meeting was in effect the real bloodline for the whole endeavour,” says Novak.

Watch the sarcophagus roof being hoisted up on giant pillars. (Credit: Novarka)

The project became known as the Shelter Implementation Plan and its first order of business was to shore up the existing sarcophagus to stop it collapsing. In the 10 years since the disaster, the only thing that had prevented further fallout was this concrete structure hastily erected in awful conditions in the months immediately after the accident. Radiation levels inside were estimated to be as high as 10,000 röntgens per hour, 20 times more than a lethal dose. The structure was in bad shape, but a straightforward repair job was out of the question.

“All proposals had to take into account the radioactive pollution,” says Novak. Protecting workers was the top priority. The last thing anyone wanted to do was send more people to their deaths.

There were many hundreds of people making decisions. Some had their own ideas, some had other plans – Vince Novak

Things were made even more difficult by the number of different opinions involved. “There were many hundreds of people making decisions, including engineers, regulators and politicians,” he says. “Some of them had their own ideas, some had other plans.”

But Novak says he was never pessimistic. That was partly thanks to a special team of 12 nuclear experts brought in from around the world, chaired by Carlo Mancini of Italy. The members of the group were not aligned with any government or organisation and, once approved by the assembly representing the international donors, their opinions could not be dismissed, for any reason.

Still, it would take another 10 years to ready the site for the new structure. “We thought that we should by all means avoid a collapse, because a collapse would have created an extremely complicated, if not impossible, environment for work,” says Mancini.

Watch the built structure begin its final journey. (Credit: Novarka)

They only realised just how bad things were once they started work in 1999, however. “The Soviets lowered the beams into that sarcophagus using helicopters and the whole structure of the roof was in fact built the same way, using helicopters,” says Novak. Pieces had been dropped in one by one and not tied together.

“They were just sitting there and what quickly became apparent was that either these beams were sliding or that the wall was moving,” he says. “It came to a point where further movement of an inch or so would have led to the huge beams falling down. You would have a collapse of the shelter.”

Those involved felt that the conditions for work totally inadequate. But the risk of not doing anything was too great

Novak remembers how tense that moment was for everyone involved. Both the European Bank for Reconstruction and Development and the project management unit – which included US construction giant Bechtel, Electricite de France and the Batelle Memorial Institute, a nonprofit research and development organisation based in Columbus, Ohio – felt that the conditions for work were totally inadequate. But the risk of not doing anything was too great. They made the decision to intervene and probably avoided another catastrophe at Chernobyl.

Meanwhile, work on the new sarcophagus itself was going ahead. A French consortium called Novarka had been tasked with building it and in 2004 Ukraine’s government approved the design. To minimise exposure to radiation for the workers, Novarka decided to erect the vast structure 300m away from the accident site and then move it into position once complete.   

The segments of the sarcophagus were actually built and pre-assembled in Italy. They had to be shipped by sea to Ukraine, then trucked to the site in Chernobyl. It took 18 ships and 2,500 trucks to complete this gargantuan task. The basic framework was erected on site in late 2014. By this point, it was 28 years since the Chernobyl accident. In that time, Ukraine had gone through two revolutions and was now in the midst of a full scale war.

Over the next two years, the interior of the sarcophagus was assembled, including advanced ventilation systems and remote controlled robotic cranes that would dismantle the existing Soviet-built structure and reactor once the new one was sealed.

The entire building was moved into its final resting place on 29 November 2016, 30 years and seven months since the explosion that set all of this in motion.

More than 10,000 people were involved in this project, chief among them Mancini. “I am extremely satisfied with the outcome,” he says. “And let me also say that I am a bit proud because of my involvement. I’ve come largely to the end of my professional career and this is the cherry on top.”

Many of those here in the hospitality tent echo Mancini’s sentiments. For Novak, constructing this tomb was akin to building a new wonder of the world.

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