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NEWS-LEADING DEVELOPMENTS
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.
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.
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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.
Pan American Silver to Acquire Minefinders Pan American Silver and Minefinders announced on January 23 an agreement for Pan American to acquire Minefinders by way of a plan of arrangement. The pro- posed transaction implies a value for Minefinders of about C$1.5 billion in cash and Pan American shares. Upon comple- tion of the transaction, existing Mine- finders shareholders will own approximate- ly 33% of Pan American on a fully diluted basis. Market capitalization of the com- bined company will be about C$4 billion. The companies expect to complete the transaction by the end of March 2012. Minefinders operates the Dolores gold and silver mine in the Sierra Madre Occidental Range of northern Mexico, approximately 250 km west of the city of
Chihuahua. The mine has a well-defined deposit and an open-pit mine life of 16 years. Proven and probable reserves total 2 million oz of gold and 114.5 million oz of silver.
The combined company will have eight operating mines and an extensive portfolio of development and exploration projects throughout the Americas. Combined silver production of the companies during 2011 totaled about 26 million oz, 52% from Mexico, 21% from Peru, 15% from Argentina, and 12% from Bolivia. The com- bined company will have 350 million oz of proven and probable silver reserves and 3 million oz of proven and probable gold reserves, with significant additional meas- ured, indicated, and inferred resources. Geoff Burns, president and CEO of Pan American, said: "Given the location of Minefinders' assets, we believe this acqui- sition is logical and consistent with Pan American's vision to become the largest, low-cost primary producer of silver in the world. Silver production from Minefinders' Dolores mine has increased almost 200% over the last year, and we expect to see fur- ther increases into the future. As a produc- ing, long-life, low-cost mine, Dolores will not only add to Pan American's production but will help balance our entire portfolio of producing and development assets. "Minefinders also has significant expan- sion potential and exceptional exploration opportunities at Dolores and a number of other promising early-stage properties."
EPA Reveals 2010 Toxics Release Inventory Analysis In its 2010
, released January
5, 2012, the U.S. Environmental Protection Agency reported that metal mining account-
www.e-mj.com
National Analysis Overview T o
xics Release Inventory
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