Feb. 26 (Bloomberg) --Freeport-McMoRan Copper & Gold Inc. and partner Cia. de Minas Buenaventura SA are studying a $3.5 billion expansion of their Cerro Verde copper mine, Buenaventura Chief Executive Officer Roque Benavides said.

An expansion that could triple copper treatment capacity at Peru’s third-largest copper mine depends on water and mine waste storage availability, Benavides said today on a conference call with analysts. Peru is the world’s second-largest copper producer after Chile.

"A feasibility study on whether to double or triple treatment capacity should be ready within the next couple of weeks,” Benavides said. "Cerro Verde has a huge resource that can and will be developed.”

Phoenix-based Freeport and Buenaventura are seeking to expand Cerro Verde after the price of copper tripled over the past two years. The mine, in which Buenaventura holds a 19 percent stake, produced 302,711 metric tons of copper last year and contributed $72 million to fourth-quarter profit, for the first time higher than its 44 percent stake in Newmont Mining Corp.’s Yanacocha gold mine, which contributed $61 million.

Newmont plans to tap new underground reserves at Yanacocha, Latin America’s largest gold mine, Benavides said. Output at the open-pit mine is slated to fall for a second year to 1.3 million ounces in 2011.

Gold Fields Ltd. and Buenaventura will also finish a feasibility study at the end of the year for the Chucapaca gold deposit, which could produce 500,000 ounces a year by 2015, exploration vice president Cesar Vidal said on the call.

Buenaventura’s American depositary receipts, each representing one ordinary share, fell 27 cents, or 0.6 percent, to $45.37 at 1:05 p.m. in New York Stock Exchange composite trading.