Building the Antamina mine in Peru required the construction of a 1,000 m long x 130 m high concrete-face, rock-fill tailings starter dam to impound water for start-up of milling operations and for subsequent retention of tailings.
The sedimentary bedrock geology consisted of siltstones and mudstones with interbedded limestone layers, including various discontinuities such as faults and open joints.
The grout curtain for the tailings starter dam required 40,000 m of drilling and injection of 2,800 tonnes of cement.
It was critical that the grout curtain be completed to the required performance standards prior to the winter rainy season to impound sufficient water for startup of the mill.
The project engineers were concerned that the dam contractor did not have sufficient expertise and resources to accomplish the required scope of grouting work on schedule and retained Peter White to provide ongoing technical support for the contractor’s grouting operations.
Working with the owner’s engineering team and the contractor’s construction crews, Peter White was involved in all aspects of the tailings starter dam grout curtain, providing hands-on direction of grouting operations being undertaken by various specialty subcontractors.
In addition, Peter quickly designed and site-fabricated real-time grout monitoring equipment with computer-based data collection to provide relevant grouting and water testing information for review and analysis by the project engineering team.
After months of around-the-clock drilling and grouting work, the tailings starter dam grout curtain was successfully completed on schedule in advance of the winter rainy season. The Antamina mill was commissioned on schedule the following year.