Dr. Dang Trung Thuan, chair of the Vietnam Geochemistry Association, said it would be not as easy as Vinacomin, the investor of the Central Highlands’ bauxite project — to revert to the original state and recover the environment at the mining site.
Reverting land’s original state before rainy season is a must
In principle, it’s quite feasible to revert to the land’s original state after the mining. Thuan confirmed that the plantation can begin three years after the exploitation ended. He also said that no need to worry about what plants to grow in the Central Highlands, because the soil there is good enough for many varieties of plants, from tea to coffee, rubber or pine.
Vinacomin has also committed to follow necessary steps in the mining and post-mining land rehabilitation when implementing the bauxite project. However, scientists have warned that it would be very costly to rehabilitate the environment, which would make the production costs high.
Both Tan Rai and Nhan Co are located in the area with high rainfall, about 2,200-2,800 mm per annum. Therefore, the mining should be carried out in the dry season, while the land rehabilitation work needs to be complete before the rainy season. If not, the rain would blow off the soil.
Especially, in some areas of Dak Nong province, the top soil above the bauxite layer is very thin. Therefore, Vinacomin has been warned that there may be not enough humus for the rehabilitation.
Scientists have every reason to have doubts if the rehabilitation can be carried out in a true way. Thuan has recalled the coal mining in Quang Ninh province and titanium exploitation in Binh Dinh province, which were also implemented by Vinacomin, to prove that “it’s easier promised than done.”
“How much area in the localities has been rehabilitated?” Thuan questioned.
It is true that trees were planted in Binh Dinh province after the mines were closed. However, only a small percentage of the trees has been staying alive, while the majority of them died.
“In principle, trees can be planted again after 2-3 years after the mining. But the question is whether the plants can grow up?” Thuan said.
Red dust - a big headache
Thuan does not worry about the pollution caused by the alumin transportation, because he believes that alumin would be packaged well for the carrying.
However, the expert has the worry about the possible water pollution in the rainy season and the red dust in the dry season.
In the rainy season, the heavy rainfall would pour to the mining sites. From the sites, the rain water would bring red soil to the rivers and streams, thus seriously affecting the quality of the water which would go to the southeast region and other lowland areas.
Meanwhile, in the dry season, the mining would pollute the environment with the dust and the waste from the machines used at the sites and the ore sifting factories.
At the factories like Nhan Co or Tan Rai, in order to make 600,000 tonnes of alumin a year, the mining would have to provide 3 million tonnes of crude ores. This means that 300,000 carrying trips are needed to transport the ores. Meanwhile, the dry season lasts many months in the Central Highlands, from October to May. This means that the volume of dust to be generated would be very big which would harm local people.
Vinacomin promised to carry ores with the trucks with the tonnage of 15-20 tons to protect the roads. However, with such the light tonnage vehicles, it’s would be very costly to carry ores, which would make the production costs higher.
