Mexican civil protection authorities in the northern state of Sonora issued on Sunday a new alert of a toxic spill in the Bacanuchi River from a copper mine operated by Buenavista del Cobre, a subsidiary company of Grupo Mexico SAB (GMEXICOB).
The alert triggered protection measures for the surrounding Sonora River population. Some 25,000 residents of the area have been urged to avoid using the water after local municipalities complained of a toxic plume where the spill occurred. The population of the area has gone without a reliable water supply for 45 days.
The announcement came after authorities flew over the area which according to them had an abnormal orange stain. They estimated that the mine contaminated the river with 40 thousand cubic meters of sulfuric acid.
Meanwhile GMEXICOB said today in a statement that heavy rains during Hurricane Odile caused new flooding, sparking pollution concerns in the mine. According to the company, the bad weather caused two reservoirs at the mine to fill with water, prompting them to activate pumping teams in order to contain the situation.
A spill at the same mine on August 6 contaminated the water supplies of at least 24,000 people, according to the government. The company has denied the accusations and has set up a US$150 million trust to pay damages.
Mexico's environmental authorities accused the company of lying about the spilling of millions of gallons of acids and heavy metals that contaminated two rivers and a dam downstream, and they said the company also lied about the measures it took to control the effects.