Recent Argentine government approval of an amended EIS will allow Goldcorp to expand future plant throughput at its Cerro Negro gold project to to 4,000 mt/d,
more than double the original planned rate. Shown here is a diagram of the site layout and a computer-generated illustration of the plant arrangement.

El Morro: Goldcorp will begin construc-tion at El Morro in September. Goldcorp is 70% owner and operator of the project; New Gold Inc. holds the remaining 30%. Capital cost to develop the project is esti-mated at $3.9 billion.

Initial production at El Morro is expect-ed in 2017, followed by full production in 2018. Production is planned to average more than 300,000 oz/y of gold and 285 million lb/y of copper over a 17-year mine life. Life-of-mine cash costs are expected to be about negative $700/oz of gold on a byproduct basis and $550/oz of gold on a co-product basis.

The El Morro project is located in Huasco province about 800 km north of Santiago. The project is based on mining and milling of sulphide copper and gold ore from the La Fortuna mineral deposit. Current open-pit proven and probable min-eral reserves total 537 million mt grading 0.52% copper and 0.49 g/mt gold (6.1 bil-lion lb of copper and 8.4 million oz of gold).

Plant throughput is planned at a rate of 90,000 mt/d. The flowsheet includes a crushing plant, semi-autogenous grinding circuit, rougher flotation and regrind circuit, and cleaner and scavenger flotation banks. Additional project-related infrastructure includes a desalination plant, power plant and concentrate filtration plant.

A new access route will be built between the project and the Pan American highway. This route will also serve as the concentrate and water pipeline route and is the pre-ferred location for the project power line.

Water supply is planned to be sourced from a reverse-osmosis desalination plant to be constructed approximately 60 km north of the town of Huasco. The planned desalination plant will produce 740 l/sec of agricultural-quality water, which will be pumped to the mine site along a 193-km-long water pipeline.

Concentrate will be transferred via pipeline to a concentrate filter plant at the port site for overseas shipment.

Cerro Negro: In mid-December, Goldcorp said it received approval from the government of Santa Cruz province, Argentina for an amended environmental impact statement (EIS) for its Cerro Negro gold project. The approval provides for an increase in plant throughput to 4,000 mt/d from a previously approved level of 1,850 mt/d.

Gold production at Cerro Negro is now planned to average 550,000 oz/y during the first five full years of operation at aver-age cash costs of less than $200/oz. Based on existing reserves, annual production over a 12-year mine life is expected to average 340,000 oz/y at cash costs of $290/oz. Total capital expenditures to first production in mid-2013 are estimated at about $750 million.

Mine planning for Cerro Negro calls for concurrent development and mining of three underground vein deposits: Eureka, Mariana Central and Mariana Norte. Total underground development of the Eureka vein had reached 2,939 m in early December 2011, including advance of the decline to 1,597 m of an expected total length of 3,900 m. Horizontal develop-ment had begun on several levels in prepa-ration for production mining, and two ven-tilation shafts had been completed.

Mine development on the Mariana Central and Mariana Norte deposits began immediately following approval of the amended project environmental impact statement.

The Cerro Negro project is located on the Patagonian plains of southern Argentina at an elevation of about 600 m above sea level. Project infrastructure is excellent, with paved and gravel road access to the nearest provincial town of Las Heras, 110 km to the northeast.