Officials in Mexico imposed water restrictions on towns and cities along a river in the state of Sonora following a spill late last week of around 10 million gallons of contaminated wastewater containing sulfuric acid from mining operations in the north of the country.
Local media and residents reported the river turning a bright orange, and fish and livestock dying from the contamination.
The wastewater came from the Buenavista copper mine in Cananea, Mexico, situated only about 25 miles from the U.S. border, and contaminated the Bacanuchi River, a tributary of the Sonora River. The spill affects seven different municipalities, including the state capital of Hermosillo, which has a population of nearly 800,000 people, although the river is not a major water source for the capital.
PROFEPA, Mexico’s federal agency charged with environmental protection, is monitoring water quality at multiple points along the river and has already ordered that the company, Buenavista del Cobre, part of the mining giant Grupo Mexico, provide “full remediation” for the spill.
“In addition to ordering the implementation of a total remediation plan, PROFEPA initiated proceedings against Buenavista del Cobre to determine possible sanctions,” the agency said on its website.
According to the Spanish-language website iagua, “authorities have said the concentration of sulfuric acid is low, but have advised people not to swim in the river until further notice.”
But many affected residents said the alerts concerning the spill came long after they noticed effects from it.
All day Friday “the water was a bright, bright orange, and smelled like it was rotten,” a resident from Tahuinchopa, in the Arizpe municipality said on Saturday. “My animals drank it, and just now they told me that two cows died.”
“The bad thing is that nobody said anything, nobody warned us,” agreed resident Patricia Serrano. “People were panicked; imagine if they told you you can’t have contact with the water, not even to wash or bathe yourself.”
The state of Sonora is Mexico’s leading producer of gold, copper, and graphite.
In 2009 an American subsidiary of Grupo Mexico, Asarco, payed the U.S. government a record $1.79 billion to settle hazardous waste pollution in 19 U.S. states.