Nuclear disaster averted

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Nuclear disaster averted

Russian power plant workers praised for 'heroic' operation to cool reactors

Special report: Russia

Amelia Gentleman in Moscow Sunday September 17, 2000

A nuclear catastrophe - triggered by a fault in Russia's ageing electrical grid - was averted last week thanks to a 'heroic' emergency operation by power station workers. Details of how one of Russia's main nuclear plants and the country's largest plutonium-processing centre came close to disaster emerged slowly, prompting new alarm in a country still reeling from a string of disasters.

Nuclear experts said 'courageous' workers at the Beloyarsk power station and the Mayak reprocessing plant had managed to prevent a Chernobyl-style accident. Environmental campaigners warned that the crumbling state of Russia's infrastructure meant such close escapes could be expected with growing frequency.

Preliminary investigations showed that a short circuit in the regional electricity system caused a sudden blackout in three nuclear reactors in the Urals. Its cause remains unclear, although it has been widely attributed to a fault in the poorly maintained network.

Unexpected power cuts at nuclear plants, which are designed to work ceaselessly, pose a severe risk. There was controversy yesterday over whether built-in emergency electricity systems took over as they should have done. Minatom, Russia's Ministry of Atomic Energy, insisted that all back-up systems at both sites began working in the seconds after the accident, but environmental activists reported that the standby electricity generators of at least one of the reactors had failed to start.

These sources say a technical hitch at the Beloyarsk plant, in the Sverdlovsk region, meant that the diesel generators built into the reactor failed to start automatically. Without a separate supply of electricity, the cooling system at the heart of the plant allegedly stopped working - causing the temperature in the core reactor to soar to dangerous levels, as workers lost control over the chain reactions occurring within.

'The problem was that the diesel generators were in poor condition and so the staff on the plant needed 36 minutes to repair them to get them started,' said Vladimir Slivyak, co-chairman of the Ecodefence organisation, which has spent the past week gathering information about the mishap. 'It was up to the personnel on the plant to avert a serious nuclear accident. They worked heroically.'

Alexei Yablokov of the Centre for Ecological Problems of Russia endorsed this view: 'We were just half an hour from another Chernobyl - had it not been for the professionalism of the plant staff.'

At around lunchtime on Saturday last weekend, a crash echoed from within the walls of the Beloyarsk compound. Local residents - many of whom were celebrating the annual town festival - listened in horror. Most of the people who live in Zarechny, the settlement which has grown up around the plant, are either current or former employees - so were well equipped to judge the gravity of the noise.

The precise cause of the sound remains unclear. Unconfirmed sources suggest that while technicians struggled to get the diesel generators working, they were forced to shut down the reactor manually. Residents may have heard steam spurting suddenly from the cooling plant, as pressure in the system mounted.

One of the immediate results of the shutdown at Beloyarsk was a power failure at the nearby Mayak processing plant in the Chelyabinsk region, where two reactors were in operation.

The potential consequences of malfunction at the vast, high-security Mayak plant are no less alarming. Scientists there take spent nuclear fuel from all over the former Soviet Union and convert it into weapons-grade plutonium and high-level waste. The site is estimated to contain 120 million curies of radioactive waste - much of it held in liquid form in vast tanks - including seven times the amount of strontium-90 and caesium-137 that was released in Chernobyl.

Mayak was without power for 45 minutes and the reactors were automatically shut down. The head of the plant, Vitaliy Sadovnikov, told a local newspaper that this was the worst blackout the station had faced and it was only his staff's 'near-military discipline' which prevented a serious accident.

He said the back-up electricity provider, designed to cool down the reactors in the event of such an emergency, had only been started up 30 minutes after the plant was brought to a halt.

But yesterday Bulat Nigmatulin, a Deputy Minister at Minatom, said these reports were lies. 'This unpleasant situation came about because for the first time there was a breakdown in the local energy system,' he said.

'The atomic installations at Beloyarsk and Mayak are protected against this kind of accident, and on this occasion everything went exactly according to plan, with on-site emergency electricity sources starting up immediately.'

He said 30-minute delays would have led to explosions in the reactors.

Officials at both plants report there was no radiation contamination as a result of the emergency shutdowns. Environmental activists in the region continue to test the site, but are so far satisfied that this is the case.

Although a crisis was averted, analysts agree that both mishaps are sobering examples of the ease with which a disaster could be sparked.

'The fact that the grid was down for 45 minutes is extremely alarming, because it means that control was temporarily lost in these crucial nuclear installations,' said Tobias Muenchmeyer, atomic energy expert with Greenpeace.

Some commentators linked the initial power cut to the campaign by Russia's electricity monopoly to cut off those customers with outstanding debts. They speculated that by suddenly switching off one area of the grid, Unified Energy Systems might have precipitated the short circuit. UES officials deny this, and a government commission has been set up to investigate.

State officials are eager to promote atomic energy as a means of heating and powering their vast country. A strategy document published by Minatom in May advocated that Russia should radically increase its nuclear capacity over the next 20 years, building up to 24 new reactors.

Independent experts affirm that over the past five years the number of emergency shutdowns in Russian reactors has dropped fourfold, and over the past two years financing of safety monitoring has increased. But the memory of the Chernobyl disaster 14 years ago remains uncomfortably fresh.

http://www.guardian.co.uk/russia/article/0,2763,369486,00.html

-- Martin Thompson (mthom1927@aol.com), September 17, 2000


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