Grupo Mexico mine spill

On 7 August 2014 40,000 cubic meters of waste water, comprising acid – laced copper sulphate and heavy minerals, spilled from a copper mine in Northern Mexico into two rivers just 40 km from the US border.1  This toxic leak originated from the Beunavista Copper Mine in Cananea Sonora, operated by the mining company Grupo Mexico.

In response to the spill, Mexico’s National Water Commission said it was monitoring the chemicals in the water closely.2The Commission established that concentrations of Arsenic and some metals exceeded permitted levels and was required to shut off water use from the dam, resulting in tens of thousands in Sonora state having no access to water and forcing schools to shut down. The spill also severely damaged the environment, killing fish and animals drinking from the river.3

The report given by the mining company, Grupo Mexico, regarding the cause of the spill was that it was as a result of ‘unusual rainfall’. This was later reported as having been totally false, with Mexico’s Environment Secretary confirming that the mine gave false information and indeed there was no rain on the day of the spill.4A criminal complaint has been filed against the mine, as authorities believe the spill was caused by defects in newly constructed leaching ponds.5Grupo Mexico will be facing a fine for the spill, which could be as high as US$3 million. In addition, the Latin American Herald Tribune Reports that the Mexican Human Rights Commission will be investigating the spill in terms of it breaching human rights standards.3 

According to, banks with current funds invested in and supporting Grupo Mexico include HSBC, Deutsche Bank, Black Rock, Credit Suisse, BNP, ING, UBS as well as insurers AXA.

  1. Wtop: Mexican mining firm complains about probe of spill. Available at: Last accessed on 27.08.2014 []
  2. Mexico copper mine spill pollutes water supplies 40 km from U.S. border. Available at: Last accessed on 27.08.2014 []
  3. Latin American Herald Tribune: Human Rights Commission investigates Acid Spill in Mexican River. Available at: Last accessed on 27.08.2014 [] []
  4. Mexican mining company lied on spill: government. Available at: Last accessed on 27.08.2014 []
  5. Jurist: Mexico environmental agency sues copper mining company over spill. Available at: Last accessed on 28.08.2014 []