Pictured: The colossal cap being lowered over exploded nuclear reactor to protect the world from Chernobyl's crumbling tomb

Workers raised first section of colossal arch-shaped structure that will help clean up the consequences of explosion



Upon completion, £1.2bn shelter will be moved on tracks over building containing destroyed reactor, allowing work to begin on dismantling the reactor and disposing of radioactive waste

World's worst nuclear accident led to more than 6,000 cases of cancer, 115,000 evacuations and 23 deaths

Photographs shows scene of devastation 26 years on from the Chernobyl disaster, leaving Pripyat a ghostly town




Workers have raised the first section of a colossal arch-shaped structure that will cover the exploded nuclear reactor at the Chernobyl power station.

It is part of a £1.2bn project to clean up the damage caused by the world's worst nuclear accident in the then Soviet republic of Ukraine - which led to more than 6,000 cases of cancer, 115,000 forced evacuations and 28 deaths due to radiation sickness.

And 26 years on from the Chernobyl disaster, photographs captured yesterday show the scenes of devastation left behind in and around the town of Pripyat, where the plant's workers once lived.

A ghostly ruin of deteriorating apartment towers and remnants of a once happy existence for thousands of inhabitants are part of the legacy of the 1986 explosion.

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Staff work on the new structure at the site of the Chernobyl nuclear reactor yesterday. The first section of the colossal arch-shaped structure has now been raised

Devastation: A playground in the deserted town of Pripyat, Ukraine, some 3kim from the Chernobyl nuclear power plant

Remnants: An abandoned nursery in the deserted city of Pripyat, which was built to house the workers of the Chernobyl nuclear power station

Project officials on Tuesday have hailed the arch raising as a significant step in a complex effort to clean up the consequences of the explosion.

Upon completion, the shelter will be moved on tracks over the building containing the destroyed reactor, allowing work to begin on dismantling the reactor and disposing of radioactive waste.

Suma Chakrabati, president of the European Bank for Reconstruction and Development, which is leading the project, called Tuesday 'a very significant milestone, which is a tribute to the ongoing commitment of the international donor community, and an important step towards overcoming the legacy of the accident.'

The shelter, shaped like a gargantuan Quonset hut, will be 843ft by 492 ft when completed and at its apex will be higher than the Statue of Liberty.

The April 26, 1986, accident in the then-Soviet republic of Ukraine sent a cloud of radioactive fallout over much of Europe and forced the evacuation of about 115,000 people from the plant's vicinity.



Construction workers assist in the assembly of a gigantic steel-arch to cover the remnants of the exploded reactor

The new safe confinement, a structure that is being built over reactor 4 damaged in 1986 as a result of the world's worst nuclear accident, will cover a hastily built sarcophagus, which was erected shortly after the explosion

A 30km area directly around the plant remains largely off-limits and the town of Pripyat, where the plant's workers once lived, today is completely deserted.



At least 28 people have died of acute radiation sickness from close exposure to the shattered reactor and more than 6,000 cases of thyroid cancer have been detected in people who, as children or adolescents, were exposed to high levels of fallout after the blast.

Officials who showed reporters around the construction site Tuesday were clearly delighted at the colossus taking shape before them, but concerned about the challenges ahead.



Deserted: 115,000 people had to be evacuated from the Ukraine, leaving their belongings behind, following the nuclear explosion

A toy lies in the window frame of a nursery in the deserted town of in Pripyat after the world's worst nuclear accident

A view of empty houses in the town of Pripyat near the closed Chernobyl nuclear power plant after thousands fled the area over 25 years ago

The shelter is to be moved over the reactor building by the end of 2015 - a deadline that no one wants to miss given that the so-called sarcophagus hastily built over the reactor building after the 1986 explosion has an estimated service life of about 30 years.

The arch now under construction is only one of two segments that will eventually form the shelter, and so far it's only been raised to a height of 72ft.



More structural elements have to be added before it reaches its full height of 354ft, and the work so far has taken seven months.

'There's no room for error ... the schedule is very tight,' said Vince Novak, director of the EBRD's nuclear safety department, who added that staying within budget is also a concern.

Abandoned: The vast area has not been inhabited since the 1980s in the fear that people would be contaminated

A 30km area directly around the plant remains largely off-limits and the town of Pripyat, where the plant's workers once lived, today is a ghostly ruin of deteriorating apartment towers

Desolate: The April 26, 1986, accident in the then-Soviet republic of Ukraine sent a cloud of radioactive fallout over much of Europe

The overall shelter project is budgeted at £1.2bn ($2 billion) - £0.8bn ($1.3 billion) of that for the structure itself - and much uncertainty lies ahead.



One particular concern is dismantling the plant's chimney, which must be taken down before the shelter is put in place.



The chimney is lined with radioactive residue that could break up and enter the atmosphere as it is taken apart.



Laurin Dodd, managing director of the shelter project management group, said some sort of fixative will have to be applied to the chimney's interior.

'This is one of the most challenging parts, because it's an unknown,' he said.

Hope: A cross with a crucifix is seen left standing in the deserted Ukrainian town yesterday

A fun park once used by families has been left unused for years as local fled for safety in the disaster

View of the town: The structure will be built over the now-decaying containment built in 1986 and dubbed the 'Sarcophagus'

Other possible delays could come if excavations for the shelter's foundation uncover radioactive waste or even buried machinery.



Dodd said other excavations unearthed several bulldozers and cranes that had to be decontaminated.

Even when the shelter is in place, the area around the reactor building will remain hazardous.



The shelter is aimed only at blocking radioactive material from escaping when the reactor is being dismantled; it won't block radiation itself.

The damaged reactor at the Chernobyl nuclear power plant in Chernobyl, Ukraine as it disappears into the low cloud cover

But when the dismantling and cleanup work is complete, the radiation danger will decline.



How long that would take is unclear, but officials on Tuesday allowed themselves to envision a happier Chernobyl a century from now, with the plant's director speculating that the huge shelter may even become a tourist attraction.

Plant director Igor Gramotkin drew a parallel between the shelter and the Eiffel Tower.