Company’s own new figures show leak had been massively underestimated

The amount of cyanide solution that spilled from Barrick Gold’s Veladero mine in San Juan province is almost five times more than previously believed, the company acknowledged yesterday as a second federal prosecutor moved to investigate national and provincial officials and mining executives amid growing environmental concerns.

By Barrick’s own estimates, approximately 1,072 cubic metres (1.072 million litres) of cyanide solution made it into the Potrerillos River, due to a valve failure and a sluice gate being left open on September 12.

Previous upper estimates of the spill had been in the realm of 224,000 litres. The Canadian multinational chalked up the revised number to the pinpointing of the approximate time of the valve failure, believed to be around 8pm. The cyanide solution is used to leach gold from processed rocks, a common method for the extraction of gold from ore.

Despite the revised estimate, Barrick insists the spill will not lead to any health risks for area residents.

As a reference to understand the magnitude of the spill, Olympic-sized swimming pools have a volume of 2.5 million litres.

Cyanide leaching operations have been put on hold due to a judge’s order since the spill,and the company is currently in the process of carrying out upgrades to the mine to ensure that another spill does not take place.

At this time though the company has yet to determine why a sluice gate that should have been closed was left open. That failure allowed the cyanide solution to bypass emergency pools and to enter the Potrerillos River.

A court-ordered investigation has established that the water supplies for the surrounding towns are safe to drink but the tests are still ongoing and it remains to be seen if aquifers have been contaminated.

Source: Buenos Aires Herald.com - see full article