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Issue link: https://emj.epubxp.com/i/102812
NEWS-CONTINUED (Latin America Regional News - from p. 14) Minera Antucoya Suspends Project Development Antofagasta plc announced on December 21, 2012 that Minera Antucoya (70% Antofagasta, 30% Marubeni Corp.) has decided to temporarily suspend development of the Antucoya copper project in Chile's Antofagasta region to enable a full review of the project given existing and potential levels of cost escalation. Antucoya immediately issued notices of termination under the principal construction contracts for the project. The Antucoya project is based on a copper oxide deposit located 45 km east of Antofagasta's Michilla mine. Project development was announced in December 2011. Production was expected to average of 80,000 mt/y of copper cathodes through a standard heap-leach process over a mine life of about 20 years, with production starting during the second half of 2014 Capital cost to develop the project initially was estimated at $1.3 billion. In May 2012, the estimate was raised to $1.7 billion. Diego Hernandez, CEO of Antofagasta Minerals S.A., commented, "We remain (Australia/Oceania Regional News - from p. 16) Fortescue Opens Rail Line Serving Its Solomon Hub Fortescue Metals dispatched the first train load of iron ore from its Solomon mining hub in Western Australia in early December 2012, as it opened the new rail link from the hub to an existing mainline railway from its Chichester hub to Herb Elliot Port. The train of 240 ore cars carried 23,000 mt of ore from the Solomon hub's Firetail deposit 130 km along the new rail link and then 175 km along the existing mainline railway to the port. The new rail link has been named the Fortescue Hamersley Line. Following the ramp-up of the Firetail ore processing facility at Solomon in March 2013, Fortescue will operate 11 trains per day from its three operations, the Cloudbreak and Christmas Creek mines in the Chichester hub and the Firetail mine at Solomon. The trains will each haul up to 33,000 mt of ore and will complete at least one trip each per day to the Herb Elliott Port. The Solomon hub, located 60 km north of Tom Price, will produce an initial 20 million mt/y from the Firetail deposit. A www.e-mj.com concerned about the level of capital and operating costs in the industry. We believe Antucoya's decision to temporarily suspend and review the project reflects an appropriate and measured approach to addressing these concerns. Silver Standard Reports Positive Feasibility Study for Pitarrilla Silver Standard Resources has reported the results of a positive feasibility study of its 100%-owned Pitarrilla open-pit silver project 160 km north-northwest of the city of Durango within the state of Durango, Mexico. The study evaluates a 32-year project producing an average of 15 million oz/y of silver during the first 18 years of production. Life-of-mine production is estimated at 333 million oz of silver, 582 million lb of lead, and 1.7 million lb of zinc. Probable mineral reserves at Pitarrilla currently total 43.4 million mt of direct leach ore grading 91.5 g/mt silver and 113.2 million mt of flotation/leach ore grading 96.5 g/mt silver, for a total of 479 million oz of contained silver. Total construction costs to develop the project are estimated at $741 million, including $157 million of second stage of development, the 40-million-mt/y Kings deposit, will lift production at the Solomon hub to 60 million mt/y. Fortescue slowed development of the Kings mining operation in September 2012 because of volatile market conditions. The company is now considering accelerating that development, with a view to reaching its production target of 155 million mt/y of iron ore from all of its mines by the end of 2013. In mid-December 2012, Fortescue announced that it had begun a process to consider the potential sale of a minority interest in its 100%-owned "The Pilbara Infrastructure" (TPI) subsidiary that owns the company's rail and port assets. Fortescue CEO Nev Power said the company has received strong interest from a number of strategic and financial parties interested in investing in TPI. Nautilus Minerals Terminates Equipment Build Nautilus Minerals announced in midNovember 2012 that due to a financing dispute with the State of Papua New Guinea, it has terminated construction of equipment for the seafloor production sys- pre-production operating costs and $131 million of pre-production revenue. Pitarrilla will use standard truck-and-shovel open-pit mining methods. The expected mining life is 20 years, including three preproduction years. The plant will be designed to process 12,000 mt/d of direct leach ore and 16,000 mt/d of flotationleach ore. The two ore types will utilize a common crushing and grinding circuit. Initially, highly-oxidized ore will be direct leached in an agitated leach circuit. Silver will then be extracted from the pregnant leach solution using the Merrill-Crowe process to produce silver-rich doré bars. Subsequently, the less oxidized and unweathered sulphide ores will be processed in sequential lead and zinc flotation circuits to produce separate silver-bearing lead and zinc concentrates. Tailings from the flotation circuits will be processed in the agitated leach circuit to recover additional silver. Over the project's life, the plant will produce an estimated 118.5 million oz of silver in silver-rich doré bars; 604,000 mt of lead concentrate at average grades of 43% lead and 9,500 g/mt silver; and 1.5 million mt of zinc concentrate at average grades of 46% zinc and 604 g/mt silver. tem for its Solwara 1 seafloor mining project in the Bismarck Sea, Papua New Guinea. The project development agreement calls for the State to earn a 30% interest in the project by contributing 30% of the capital for project development. Nautilus reported that it had made significant progress in developing the Solwara 1 project and that the seafloor production equipment build was 53% complete as of the end of September. The company reported that the State's capital obligation totaled $51.5 million, excluding interest, as of that date and that the State disputed that it was required to meet its obligations at that time. Lacking financial participation from the State, Nautilus decided to preserve its cash position by terminating construction of the equipment for the seafloor production system. Nautilus has other prospects in the southwest Pacific, including exploration tenements in the territorial waters of the Kingdom of Tonga. On November 1, 2012, the company announced the discovery of two high-grade seafloor massive sulphide systems on these tenements, with grab samples assaying up to 11.9% copper, 59.8% zinc, 28.6 g/mt gold, and 673 g/mt silver. JANUARY 2013 • E&MJ; 27