MG worked with Pipeline Systems Inc. (Concord, CA) and Fluor Canada Ltd (Vancouver, BC) to provide process, mechanical, and civil engineering for the basic and detailed design of a 120,000 tpd tailing system for a Peruvian copper mine at Cerro Verde.
The tailings system included a 3.5 km open channel launder, a two-stage hydrocyclone station. Sand is distributed by a spray bar system on a jacking header to allow continuous dam construction. Excess sand is deposited at the dam toe for future use. Tailings not used for dam construction was deposited behind the dam through spigotted pipeline on a separate jacking header or directed to various locations for backfilling to prevent water entrapment. For the first three years of operation the entire tailings system was gravity flow (no pumping until dam/impoundment elevation rose).
The return water system included barge mounted vertical turbine pumps and on-shore booster stations to allow water to be returned to the concentrator and hydrocyclone station simultaneously. Two barges were used to allow a continuous supply of water to the concentrator during barge relocations. Another pump station was located at the toe of the dam to allow seepage water and water drained from the construction sand to be pumped back to the hydro cyclone station.