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Mexican government files criminal charges in copper mine acid spill
Mexico’s Environmental Secretary has estimated that the fine for the Buenavista copper mine spill could reach $3 million.
Author: Dorothy KosichPosted: Wednesday , 20 Aug 2014
RENO (Mineweb) -
Mexico’s federal environmental protection regulator, Profepa, has filed criminal charges with the Federal Attorney General’s Office against Grupo Mexico’s Buenavista del Cobre and Minera Mexico over a leakage caused by defects in newly constructed leaching ponds, which contaminated two rivers and left thousands of people without drinking water.
Two days after the Mount Polley tailings dam breach in British Columbia, 40,000 cubic meters of copper sulfate acid solution from Grupo Mexico’s Buenavista mine spilled into the Bacanuchi River and, subsequently, the Sonora River in northern Sonora State.
Initially, Grupo Mexico blamed unseasonal rains for causing the acid solution to spill from a dam now under construction for a new leaching plant in the mining operation. The company said it would pay for all the damage from the accident.
Arturo Rodriguez, chief of industrial inspection for the Attorney General for Environmental Protection, suggested mine operators should have been able to detect the leak before such a large amount of drainage had leaked into the rivers
However, Mexico’s Environmental Secretary Juan Jose Guerra Abud told a local radio station Tuesday Grupo Mexico’s claim that excessive rain caused the overflow was “totally false” because there was no rain on August 6th, the day the spill is believed to have occurred.
Cesar Lagarda, northwestern division chief for Mexico’s National Water Commission (Conagua), said in a news conference that Grupo Mexico deliberately hid the failure of the tailings facility. He observed that regulators have discovered high levels of arsenic, cadium, aluminum, iron, manganese, nickel, and copper near the town of Baviacora.
Conagua has restricted water use in the communities of Arizpe, San Felipe de Jesus, Aconchi, Ures, Banamichi and Bivacire. Lime has been added to the Sonora River in an effort to neutralize the acidity.
Livestock and people have been discouraged from drinking well water within 1,500 feet of the Bacanuchi and Sonora Rivers.
However, Conagua chief David Korenfeld told the Associated Press that acids and pollutants have now become so diluted they are now within acceptable limits at a dam that supplies water to Sonora’s capital. Water is currently not being used from the dam until its safety can be assured with numerous tests, which may be concluded as early as Friday.
However, Korenfeld told AP the dam would have to raise intake levels for years to avoid stirring up potentially contaminated sediment.
Mexico’s environmental agency has suggested the fine for the spill could reach up to US$3 million. .
Gerardo Roman, head of stock trading at Actinver brokerage in Mexico City, told Reuters, “Everybody knew about the spill, but now we know about the size of the fine.”
“It’s not so much the economic impact, it’s that people don’t look kindly on them contaminating,” he stressed.
Meanwhile, on August 13th, Mexican officials reported the spill of over 500,000 gallons of cyanide used in heap-leach gold mining after heavy rains caused a retaining pond to overflow. The spill reportedly contaminated an area about half kilometer square. The Attorney General for Environmental Protection said operators of the Proyecto Magistral gold mine in Durango State were ordered to install membranes in hold ponds and raise the height of tailings dams.