Analysis: The Chernobyl legacy

Chernobyl closes 14 years after the world's biggest nuclear disaster

By BBC News Online's Environment correspondent Alex Kirby

The countryside around Chernobyl still lies bare and empty, the huge evacuation zone a silent witness to the persistent effects of the explosion 14 years ago.

Inside the plant, you could easily think yourself at the heart of a thriving, though rather threadbare, factory with a bright future stretching ahead.

Radioactive testing will go on for many years to come

Ask any of the workers whether another accident could happen, and the answer is a resounding and confident "Never!"

I visited Chernobyl just over a year ago, and I was struck by the conviction of everyone I talked to that the plant would never again pose a threat.

For them, the news of the closure will make sombre hearing - another wave of job losses in an economy that barely knows how to make ends meet at the best of times.

But should the world cheer? Does Chernobyl's closure mean the rest of Europe can sleep more easily? I doubt it.

Damage done

The radioactive by-products of the explosion will remain dangerous for hundreds of thousands of years.

The most obvious worry is the concrete sarcophagus which entombs reactor number four, the one which exploded.

It was intended to wrap the radioactive debris in an impenetrable shroud, and to prevent any contamination leaking into the air or the water.

The legacy of the nuclear disaster will not easily be forgotten

But barely 14 years later, the sarcophagus is crumbling, and if Chernobyl is ever to be safe it will have to be rebuilt or replaced, at immense cost.

Another concern is the type of reactor installed at Chernobyl.

The Soviet-designed RBMK is an inherently unsafe design and there are many other similar reactors still at work across much of eastern and central Europe.

The RBMK has what is known as a "positive void co-efficient", which in lay terms means that it has a tendency in certain circumstances to run out of control - as it did disastrously that April night in 1986.

Western reactors

Modern Western reactors, by contrast, have a negative void co-efficient, and tend to shut themselves down unless the operators intervene.

The effects of the disaster are still detectable, and research published in the UK last month said some British sheep would probably have to be kept out of the food chain for another 10 to 15 years.

In the former Soviet Union, it said, restrictions on eating some forest berries, fungi and fish would probably be needed for another 50 years.

And a final worry, despite the brave hopes of the Chernobyl workers who talked to me, is the legacy of Soviet safety culture itself.

However prudent individuals may have been, there was a tendency to believe in the invincibility of the state's technology.

There was an unwillingness to accept just how great the potential was for things to go wrong - not that the nuclear industry in the rest of the world is immune to similar delusions. With RBMKs still at work, that potential remains.

Chernobyl's closure was inevitable, and is probably overdue. But it is not the end of the story.