Roof of Chernobyl plant caves in

AFP-JIJI

A section of the Chernobyl nuclear power plant in Ukraine collapsed under the weight of snow, officials said Wednesday, raising new concerns about the condition of the facility, which suffered the world’s worst nuclear catastrophe.

There were no injuries after Tuesday’s accident or any increase in radiation from the reactor that exploded in 1986, the country’s emergency agency said. French construction firms Vinci and Bouygues said Wednesday that as a precaution they had evacuated around 80 employees working on a new protective shelter at the site.

The area of the accident is estimated at about 600 sq. meters, the agency said. “The preliminary reason for the collapse was too much snow on the roof,” it said, adding that radiation levels were “within the norm.”

A statement on the website of the power station described the accident as the “partial failure of the wall slabs and light roof of the Unit 4 Turbine Hall.” The roof was constructed after the 1986 disaster but is not part of the sarcophagus structure covering the exploded reactor.

The collapse underlines concerns about the condition of the now-defunct nuclear plant over 2½ decades after reactor No. 4 exploded.

But Chernobyl plant spokeswoman Maya Rudenko said the existing sarcophagus had been strengthened from 2004 to 2008 and could last until 2023. “There is absolutely no risk,” she said.

A Bouygues spokesman said the 80 Vinci and Bouygues workers setting up the new shelter over the exploded reactor as part of the Novarka consortium were all given radiation checks and evacuated. “Novarka is employing all measures to limit surface contamination. These are currently within admissable limits,” he said.

Chernobyl is only around 100 km from Kiev, and lies close to the borders with Russia and Belarus. The area around the plant is still highly contaminated and is designated as a depopulated “exclusion zone.”

Amid concerns about the state of the sarcophagus, an arch-shaped structure called the New Safe Confinement is being built nearby to slide over the existing sarcophagus covering the reactor. The European Bank for Reconstruction and Development is administering the fund to build the shelter with the help of donor contributions.

When it is completed in 2015, the structure will weigh 20,000 tons and span 257 meters. Since the last of the plant’s four reactors was shut down in 2000, workers at the site have been solely engaged in work to ensure safety.

Two of the plant’s employees were killed by the reactor No. 4 explosion April 26, 1986, and 28 rescue and other workers died of radiation exposure over the following months. Tens of thousands of local residents had to be evacuated. Fears remain over the scale of damage to health.

In 1986 and 1987, the Soviet government sent more than 500,000 rescue workers, known as liquidators, to clear up the power station and decontaminate the surrounding area. However, the total death toll from Chernobyl remains a subject of bitter scientific controversy, with estimates of fatalities directly attributable to the disaster ranging from no more than a few dozen to tens of thousands.