Pará state evaluates risk posed by Hydro Alunorte waste deposit

Authorities of Brazil's northern Pará state are analyzing the condition of a solid waste deposit belonging to alumina refinery Hydro Alunorte, owned by Norwegian firm Norsk Hydro.

After heavy downpours areas in and around Hydro Alunorte's production line in Barcarena were flooded and communities reported reddish water around the location. Hydro maintains that the red color of the flood stems from the soil of unpaved roads.

Local Evandro Chagas institute collected samples to detect the presence of tailings and contaminants in the water, according to Valor Economico newspaper.

So far, the state government said it did not find any signs of leakage or overflow from the waste storage area of the bauxite processing operation to obtain alumina.

Valor Economico quoted director of health, safety and environment of Norsk Hydro, Domingos Campos, as saying that the company's tailings containment system was designed to withstand millennial rains – which occur only once every 10,000 years – and was approved after severe testing.

According to the executive, the volume of water that overflowed from the areas of bauxite waste was retained by the containment basins, created especially for this purpose. "The facilities have shown that they are fully capable of withstanding this precipitation," he said. The great inconvenience, he added, in addition to the flooding of Barcarena, was the electric power outage for about an hour.

Similar problems turned into concerns for Brazilian authorities since the end of 2015, when a tailing dam of Samarco – a 50:50 JV between Australia's BHPand local miner Vale – collapsed.

As result of the catastrophe, 19 people died, 13 of them mineworkers, as one person remains missing. The tailings and sludge flowed hundreds of kilometers and polluted the Doce river before reaching the sea, still considered Brazil's worst environmental disaster.