"Mexico takes mining company to court seeking new remediation effort for Sonora river pollution", 12 October 2023

...Mexico is pursuing a criminal complaint against the country's biggest copper producer seeking to force a new remediation effort for a toxic mine spill in the northern state of Sonora nine years ago...The complaint, which was filed in August but announced only on Thursday, centers on remediation funding for eight polluted townships in Sonora.

Mining company Grupo Mexico closed its remediation fund in 2017, arguing that it had met legal requirements. The government contends that was premature and is asking the courts to order a new fund be established.

“The people, the environment are still contaminated and there are sick people,” said María Luisa Albores González, who heads the government’s Environment Department.

Albores described the August 2014 mine spill as “the most serious environmental disaster in the history of metal mining in Mexico.” Ten million gallons (40 million liters) of acidified copper sulfate flooded from a waste reservoir at Grupo Mexico's Buenavista mine into the Sonora and Bacanuchi rivers...

The company did not respond to an emailed request for comment on Albores' announcement, but in a statement it issued last week in response to the government study it said its remediation efforts were successful and legally complete...