Conceptual Design of Heap Leach Pump Back Riser Pipe

Document ID: 017303

Engineering Analytics Inc. has prepared this Technical Memorandum to present a conceptual design for a riser pipe that will allow Rosemont to install a pump back system to remove treated water from the Rosemont heap leach Treatment Basin 2 after the treatment cell has been buried by waste rock and/or tailings. Our scope of work also included the evaluation of materials that could be used to construct the riser pipe. In addition, our scope included the preparation of this Technical Memorandum.

It is our understanding that treated water meeting Arizona Aquifer Water Quality Standards (AWQS) would be allowed to flow into and out of the riser pipe and infiltrate into the ground. Treated water not meeting AWQS would be pumped out and further treated or used in the process circuit.

Nelson, E. 2012. Conceptual Design of Heap Leach Pump Back Riser Pipe. EA No. 110253. Technical Memorandum. Prepared for Rosemont Copper Company. Fort Collins, CO: Engineering Analytics, Inc. June 25.