Esperanza Thickened Tailings Project

The Esperanza tailings facility is located in northern Chile, in the Atacama Desert and will be the largest thickened tailings facility in the world. Recently, ME was distinguished with the Innovation Award of the Year 2009 in Chile for its efforts in conserving water. The most significant drivers for this award were the usage of sea water for the process and the introduction of thickened tailings to the large-scale mining industry.

The Esperanza tailings will be thickened to 67% solids and the facility has been designed to reach an average 4% beach slope. The facility was designed to store a maximum of 750 million tonnes of copper tailings.

Paste and thickened tailings are relatively new technologies in Chile, and so gaining permits for the facility was expected to be complicated. Three aspects required special consideration:
• Beach slope prediction
• Infiltration of tailings water to the ground
• Physical stability of the tailings mass – liquefaction

In order to address these issues, SRK carried out various laboratory and onsite testing of the tailings produced from the Esperanza Pilot Plant. These led us to produce a design sufficiently robust to gain permits on time.

State-of-the-art design tools and the latest in thickened tailings research were combined to interpret the relevant test results and develop practical solutions to provide an innovative TSF design, prepare a comprehensive Tailings Management Plan and streamline the approval of the relevant permits, which were granted within six months of application submittal.

The Esperanza TSF was commissioned in late 2010, with SRK acting as technical advisors.