VietNamnet Bridge – While scientists have expressed concerns about the Tan Rai bauxite plant in Lam Dong province, the investor has said that the red mud discharged from the mining area is not toxic sludge but just red-colored mud and water.

About 5,000 cubic meters of red mud discharged from the ore cleaning process (the pH is at 6/7) reportedly spread to the road linking the Tan Rai bauxite ore sifting factory after an embankment on a waste-ore reservoir broke on October 8.

A source from Lam Dong Aluminum Company said the reservoir had the capacity of 2 million cubic meters, and was used to contain mud and water discharged from the ore cleaning process. There are no chemicals and toxic substances like red mud.

However, the incident has raised concerns among the public.

Dr. Ho Uy Liem, former deputy chair of the Vietnam Union of Science and Technology Associations (VUSTA), said VUSTA’s scientists many times warned to ensure the safety of reservoirs.

“It is really worrying that such an incident occurred just a short time after the project was kicked off,” Liem said.

“I could not imagine what would happen if this was a reservoir of red mud with sodium,” he said. “The consequences would be very bad, if the mud spread over to the river and pollutes it.”

“The red mud can kill all kinds of aquatic creatures, plants and poison the underground water,” he said.

Dr. Nguyen Thanh Son, director of Vinacomin’s Coal Projects’ Management Board, said investors were alarmed about the state of red-mud containing reservoirs.

He said red-mud reservoirs were a big problem in Vietnam. Most red-mud reservoirs in other parts of the world are located in lowland areas or near the sea, which minimizes the consequences in case of incidents. If the red mud drifts into the sea, the pH level is diluted.

Meanwhile, the red-mud reservoir of the Tan Rai bauxite project is located on high land, and the investment rate of the project is lower than other projects in the world. Son said the investor needs to be very cautious with its operations.

In the latest move, the President has requested VUSTA to gather scientists and critics to discuss the problems of reservoirs.

While scientists all have expressed their concerns about the accident, the investor has been trying to reassure the public, saying that this was just red-colored mud, not red sludge (also known as red mud), the toxic substance produced at such sites.

Meanwhile, the Ministry of Natural Resources and the Environment blamed the problem on rain.

“It is true that the waste water had a red color, but this was not red mud. This is the water generated by ore cleaning, which is a necessary step before ore processing,” said the deputy general director of Vinacomin.

Dat Viet