Freeport-McMoRan Copper & Gold Inc. operates mine sites in both arid and tropical regions of the world. Whether the supply is plentiful or greatly limited, water conservation measures are integral to continued mining and ore processing operations at all our mine sites.

At our North and South American mine sites, we develop water resources using water rights, water exchanges and water withdrawal agreements. Water needs are met using surface water from local and regional water bodies and groundwater aquifers. To minimize evaporative loss, water is conveyed to several of our mine sites via pipeline. At other locations – due to topographical limitations, transportation distance and cost – water is conveyed via surface flow within existing watercourses. Additional water resources used include municipal wastewater from neighboring communities or poor quality water unusable by others.

Operational needs at our mine sites include water for leaching, solution extraction/electrowinning operations and milling operations with secondary use for dust control along mine roads, ore conveyors, tailings and in stockpile areas. Every effort is made to reclaim and reuse process water to limit new water intake.

In our hydrometallurgical leaching operations, a dilute acid-water mixture is applied to leach stockpiles for mineral extraction purposes. Evaporative losses are minimized by maximizing the use of drip application systems. The percolating fluid is later recovered and sent to a solution extraction plant where it is stripped of copper and recycled back to be reused on the leach stockpiles.

At our North and South American concentrator operations, finely ground ore is mixed with water and sent to flotation cells where mineral concentrates are recovered. The resulting tailings are initially sent to thickeners to recover water for reuse before the thickened stream is discharged to a tailings impoundment. After deposition in a tailings impoundment, suspended solids settle out and, where possible, much of the remaining water is recovered from a decant pond and pumped back to the mill for reuse. Some water is lost via evaporation and some water seeps into the tailings impoundment, where it is held as soil moisture.

At Sierrita, water balance information indicates that approximately two thirds of the site’s total make-up water demand is lost through retention, evaporation and seepage at the tailings impoundment, making Sierrita one of the highest water consumers per tonne of ore milled in Freeport-McMoRan Copper & Gold Inc. Sierrita is evaluating operating practices, improvements and technologies to minimize evaporation and seepage losses to reduce the total make-up water demand required for operations. On the other side of the spectrum is the Candelaria concentrator, where more than 85 percent of the process water requirement is from recycled water, placing the operation as one of the lowest consumers of make-up water per tonne of ore milled in the industry.

At the Atlantic Copper smelter, the company has installed a reverse osmosis plant and effluent recovery system to facilitate reuse of the water exiting the effluent treatment plant. Additional water recovery projects are also in progress. At the Indonesian concentrator, approximately 55 percent of the process water requirement is from recycled sources.

Wastewater Management

Our operations sites implement practices to reduce the volume of wastewater. These practices can include water recycling, prevention of storm water contact with process materials and water conservation. We are also undertaking several company-wide initiatives to address water effluents, including standardized storm water control and spill prevention plans, site-specific investigations to characterize and manage groundwater and surface water quality adjacent to mine facilities, and evaluation of water treatment technologies for use in short-term and long-term applications. For example, a water treatment pilot plant will be built in Arizona to test various technologies that remove sulfate and metals from water. Construction of this plant is scheduled to begin during 2008, and the test results will be applied across the company.

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