Hungarian sludge to be blocked by dam

Hungarian workers are building a dam 620 metres long and up to five metres high to contain the toxic red sludge that flooded out of a breach in the wall of an industrial waste pond last week, killing at least seven people.

Crews work on structure to block toxic red aluminum waste

The protective dam under construction Sunday next to the dike of the reservoir containing red mud. ((Gyoergy Varga/MTI/Associated Press))

Hungarian workers are building a dam 620 metres long and up to five metres high to contain the toxic red sludge that flooded out of a breach in the wall of an industrial waste pond last week, killing at least seven people.

The dam is intended to hold back any subsequent spill that might flood the town of Kolontar, the hardest-hit area in last Monday's spill, and nearby communities.

Tibor Dobson, spokesman for the Hungarian disaster agency, said there were no new cracks found in the wall of the pond overnight Saturday, but authorities are not ready to lower the state of alert.

"I would describe the situation as hopeful, but nothing has really changed," he told the Associated Press on Sunday. "The wall to protect Kolontar is planned to be finished by tonight, but it will likely be several days before residents may be able to move back."

Kolontar's 800 residents were evacuated Saturday after it appeared likely that the north wall of the pond would collapse because of cracks that had appeared.

The weather is a key factor because rain will put more pressure on the pond's walls and could wash the breached wall away, officials said.

There is a hole 50 metres wide in the northwest corner of the pond where Monday's flood began.

Aluminum byproduct

If a wall fails, a new wave of red mud could ooze north. The mud is the toxic byproduct of the industrial process that refines raw aluminum ore (bauxite) into alumina (aluminum oxide), which is then made into aluminum.

But if that happens, officials believe they will have enough time to evacuate Devecser, about four kilometres north of the pond. Devecser residents were told Saturday to be ready to leave at a moment's notice.

"This hasn't changed," Dobson said. "We are still on guard in case of any more spills."

MAL Rt., which owns the alumina plant, expressed their condolences Sunday to the families of the people killed and hurt. At least 120 people were injured, several seriously.

Hungarian investigators are trying to determine whether carelessness was a factor in the spill.

Environmental State Secretary Zoltan Illes said the company already owes about $100 million for damage it caused. Illes said he has set a two-month deadline to close the 50-metre gap because there is too much sludge in the pond to move it.

"The job, including pouring enough concrete to raise three 10-storey buildings, will have to be done from the air. This is unprecedented." 

Hungarian soldiers wearing protective suits wash the back of a truck used to clean areas flooded by toxic red sludge in Devecser on Sunday. ((Bela Szandelszky/Associated Press))

With files from The Associated Press