Hungarian sludge reservoir 'likely' to collapse

THE walls of a red sludge reservoir are "very likely" to collapse, Hungary's prime minister warned yesterday after a breakout last week killed seven people and flooded the town of Kolontar.

Viktor Orban said the town, next to the aluminium factory reservoir and badly damaged in Monday's flood, had been evacuated as a precaution because engineers think developing cracks could cause a whole side of the enormous container to collapse.

"Cracks have appeared on the northern wall of the reservoir which makes it very likely that the whole wall will collapse," Orban said in Ajka, a city near Kolontar

"We have started to build dams in the direction of the populated areas to slow the flow of the material in case of a new incident."

The prime minister said experts had estimated that 500,000 cubic metres more red sludge could escape from the reservoir if the wall collapsed, about half the original leak.

"We have no exact information about the nature of the material because a catastrophe like this has never happened before anywhere in the world," Orban said. "Human errors and mistakes must exist ... and the (legal] consequences will be very serious."

In addition to the fatalities, more than 120 people were injured when a corner of the reservoir gave way and up to 700,000 cubic metres (184 million gallons) of toxic waste flooded several towns in western Hungary.

The concentration of toxic heavy metals where the red sludge entered the Danube has dropped to the level allowed in drinking water, authorities said, easing fears that Europe's second longest river would be significantly polluted.

The sludge devastated creeks and rivers and entered the Danube on Thursday, moving downstream towards Croatia, Serbia and Romania.

Monitors were taking samples every few hours to measure damage from the spill but the sheer volume of water in the Danube appeared to be blunting the sludge's immediate toxic impact.

Despite the apparent good news, the risk of pervasive and lasting environmental damage is a real possibility at the site of the spill, with Greenpeace presenting test results that showed high concentrations of heavy metals in the sludge.

MAL Rt, the Hungarian Aluminum Production and Trade Company that owns the Ajkai Timfoldgyar plant where the spill occurred has rejected criticism suggesting it should have taken more precautions at the reservoir.

Hungarian police have confiscated documents from the company, and the National Investigation Office was looking into whether on-the-job carelessness was a factor in the disaster.

Authorities began questioning people in the case and were looking for witnesses who could provide information about the reservoir's operations and maintenance work.

There are red sludge storage sites elsewhere in western Hungary, holding at least 30 million cubic metres.

The accident's cause remained unknown. But Gusztav Winkler, a professor at the Budapest Technical University who was part of a team which examined the area's soil 30 years ago, said a bad choice of location may have played a role.

"Two entirely different soils meet here, one a sediment type and one of clay," he said. "When exposed to water, they expand, shift, to a different extent. They move."

He said the collapsed corner of the reservoir was precisely where the clay and the sediment meet in the soil, which may have helped to create tension zones inside the dam's wall.

"It's a rigid structure," he said. "You push it, it breaks."

While there is a good chance the spill's impact on the Danube will be limited, western Hungarian villages that bore the brunt of the sludge torrent could suffer in the longer term, according to environmental group Greenpeace.

Test samples from the sludge showed that government health and science agencies had underestimated the ecological dangers unleashed, Greenpeace Hungary director Zsolt Szegfalvi said.

Arsenic, mercury and chromium levels were especially high at Kolontar, he said, rejecting earlier claims by the National Academy of Sciences in which it said the alkali sludge contained no harmful levels of heavy metals.

"This contamination poses a long term risk to both the water base and the ecosystem," a Greenpeace statement said.

More than 150 people were injured in the disaster, mainly burns and eye ailments from the caustic and corrosive sludge.

All waterlife died in the smaller Marcal River, first struck by the spill. There were also reports of sporadic fish death on Thursday in the Raba and Mosoni-Danube rivers. There were no reports of major damage to the main branch of the Danube.