Authorities in Mexico said Monday they have closed about 80 schools after sulfuric acid leaked from a copper mine in the country's northwest and contaminated the Sonora River.
"About 5,000 students from around 80 schools will not have classes this week because of a lack of water and in some locations their proximity to the river," said the director of the Sonora state civil protection agency, Jesus Arias.
On August 6, some 40,000 cubic meters (10.6 million gallons) of sulfuric acid used to dissolve copper from ore for processing leaked out of a holding tank at . . .