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18 E&MJ; • JUNE 2014 www.e-mj.com REGIONAL NEWS - LATIN AMERICA Three Development Options for Exeter's Caspiche Au-Cu Deposit Exeter Resource Corp. has reported the results of a new preliminary economic assessment (PEA) of its Caspiche gold- copper deposit in northern Chile. The PEA reviews a low-capex, stand-alone, open-pit heap-leach oxide gold operation, as well as two other staged mine plans that include expanded open-pit mining and under- ground mining of the central, higher-grade gold-copper zone at Caspiche. The options are, in descending order of choice: • A stand-alone, heap-leach oxide option that would process 30,000 metric tons per day (mt/d) to produce 122,000 gold equivalent oz/y over a mine life of about 10 years, including 148,000 oz/y during the first five years of operation. Initial capex would be $251 million, including $41 million for contingencies. All-in sus- taining cash costs would be $676/gold equivalent oz. • An accelerated 60,000-mt/d, open-pit heap-leach operation producing approxi- mately 240,000 oz/y over a six-year mine life. Gold-copper sulphide mineralization would be mined from an extension of the oxide open pit, with concentrator opera- tions beginning in year six. Sulphide mineral would be mined from the open pit for an additional 12 years at a rate of 27,000 mt/d. Mineralized gold-copper- silver material would be treated in a con- ventional copper flotation concentrator, with a cyanide leach-SART-carbon col- umn plant to recover additional gold and copper from one of the flotation circuit tailings streams. • An accelerated 60,000-mt/d, open-pit heap-leach operation producing approxi- mately 250,000 oz/y over a five-year mine life. Large sub-level open-stope underground mining would start in year three, targeting the Caspiche gold-cop- per sulphide higher-grade core. Initially a single ramp would be advanced into the top of the higher-grade core. By year seven, underground mining operations would ramp up to full capacity of 27,000 mt/d with the development of a second ramp. Sulphide processing would be as in option 2. The Exeter announcement noted that, "Critical for any mine development in the Caspiche region is securing adequate water resources. Exeter continues a program to establish an independently owned water supply to minimize the cost of water pro- curement to the project. Exeter is opti- mistic that its current water program could provide quantities of water to meet all of the mining options outlined in the PEA." Conclusion of final feasibility and envi- ronmental impact studies for the top option is contingent on establishing secured water resources. First Quantum Buying Certain Petaquilla Assets for $60M First Quantum Minerals and Petaquilla Minerals announced in early May an agree- ment whereby First Quantum subsidiary Minera Panama will pay Petaquilla up to $60 million for transfer of a range of Petaquilla assets and property rights in the area of Minera Panama's Cobre Panama copper project and Petaquilla's Molejon gold mine in Colon province, Panama. The agreement ensures complete development and operational flexibility for the Cobre Panama project by providing Minera Panama with ownership of all concession application areas surrounding the Molejon Acquisition of adequate water resources will be a crucial factor in development of Exeter's Caspiche gold-copper deposit in northern Chile. A recent PEA presents both surface-only and surface-underground mining options. Goldcorp announced on May 5 that its Los Filos mine in Guerrero state, Mexico, had resumed all operations following a negoti- ated settlement with the Carrizalillo Ejido for a new land occupancy agreement with a five-year term. The Carrizalillo Ejido is the local landowners' association. Operations at Los Filos had been suspended on April 2, following unsuccessful efforts to reach a negotiated settlement to renew the occu- pancy agreement that expired on March 31 ( E&MJ; , May 2014, p. 14). Due to the suspension, Goldcorp expects 2014 gold production at Los Filos to be at the low end of its guidance range of between 330,000 and 345,000 oz. In 2013, Los Filos produced 332,400 oz of gold at all-in sustaining costs of $1,002/oz. Los Filos is a combined open-pit/under- ground operation. The mine directly employs more than 2,600 people from the surrounding communities, with an estimat- ed 10,000 additional jobs created as a result of its presence in the region. Goldcorp also reconfirmed its overall company production guidance of between 2.95 million and 3.10 million oz of gold for 2014. Goldcorp Resumes Operations at Los Filos (Continued on p. 42) EMJ_pg04-45_EMJ_pg04-45 6/4/14 9:00 AM Page 18