The giant tailings dam of Compañía Minera Antamina S.A. is currently the highest in the world and has the capacity to store 550 million tons of sterile material or 330 cubic meters during the mine’s operative life (23 years).

Built in the Huincush canyon, 3 kilometers from the Concentrator Plant, the dam has an interior reinforced concrete plate that is also protected with high-density geo membranes to avoid any possible leaks. Drainage tunnels and rainwater collection channels complement this state-of- the-art operation that guarantees environmental protection and structural stability.

Currently, the first phase of Antamina tailings dam is complete and it stands 135 meters high (4,045 meters above sea level). In the second phase it will reach 165 meters and in the third and final phase, it will be 250 meters high and 750 meters long. Its resistance is 0.48 Gp or maximum credible earthquake.

In January 2003, Golder Associates Ltd Consulting Firm won the “2002 Canadian Consulting Engineering Awards” in the mining and industry category for the design and engineering of Antamina’s tailings dam. The prize was awarded by the Association of Consulting Engineers of Canada.