Grupo Mexico’s activities in Guaymas suspended after sulfuric acid spill

Mexico’s Federal Prosecutor for Environmental Protection or Profepa ordered the partial and temporary closure of Grupo Mexico’s Guaymas facility following last week’s failure of a pressure valve of a tank that receives purges from the shipping lines at the Maritime Terminal of Guaymas, located in the northwestern Sonora state.

The accident resulted in the spill of 3,000 litres of sulfuric acid into the waters of the Sea of ​​Cortez. 

Officers from the Federal Attorney for Environmental Protection at Grupo Mexico’s facility in Guaymas. Photo by Profepa.

In a media statement, Profepa said that the closure was ordered because the mining company doesn’t have the required environmental impact permit to operate. Such a permit had to be issued by the Secretariat of Environment and Natural Resources.

“Based on article 170 section I of the General Law for Ecological Balance and Environmental Protection, and on article 47 paragraph 3 of Semarnat’s Internal Bylaw, we enforced, as a safety measure, the partial temporary closure not just of tank 19 where the breach happened, but of all operations and activities related to the storage and maritime transportation of sulfuric acid,” Profepa’s media statement reads.

The agency goes on to explain that only a few operations remain active, such as the works related to the relocation of the train tracks inside Mexicana del Cobre’s property and those related to the construction of an industrial facility aimed at storing 22,000 tonnes of copper.

Mexicana del Cobre is the subsidiary of Grupo Mexico that mines copper at the Buenavista del Cobre mine in the nearby town of Cananea and operates the Guaymas facility.   

Following the tank’s failure on July 9, Grupo Mexico’s personnel started transferring the spilled acid into a pipe. At the moment, the incident was not deemed serious enough for the maritime authorities to activate an emergency plan. This assessment was later confirmed by officers from the Secretariat of Environment and Natural Resources who visited the site last Tuesday.