Giant shelter getting placed over Chornobyl nuclear reactor

A gargantuan arch-shaped shelter has begun creeping toward the exploded Chornobyl nuclear reactor, in what represents a significant step toward liquidating the remains of the world's worst nuclear accident.

When the shelter is in place, work can begin on dismantling the so-called sarcophagus surrounding the reactor building to contain fallout from the explosion 30 years ago.

The shelter, 108 metreshigh, 165 metres long and 275 metres wide began moving Monday by a system of hydraulic jacks, according to the European Bank for Reconstruction and Development, which led the $1.6 billion US project.

"Movement of the arch over the fourth energy reactor is a historic event. Accomplishment of the measures related to the improvement of environmental and nuclear security became possible thanks to the international support, thanks to Ukrainian specialists who built this without exaggeration unique facility," said Ukraine's Ecology Minister Ostap Semerak.

On April 26, 1986, a botched test at the Soviet nuclear plant sent clouds of smouldering nuclear material across large swathes of Europe, forced over 50,000 people to evacuate and poisoned unknown numbers of workers involved in its clean-up.

A concrete sarcophagus was hastily built over the site of the badly damaged reactor to contain the worst of the radiation, but a more permanent solution has been in the works since late 2010.

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