El Pachón is a bi-national project located 3,600 metres above sea level in Argentina’s San Juan Province, five kilometres from the Chilean border. The project falls under the Mining Integration Treaty signed in 1997 by Argentina and Chile and its Specific Protocol, which will enable concentrates to be shipped via the Pacific Ocean.

The project is completing feasibility and environmental impact studies.

In December 2011 Xstrata Copper published an increase by 53% to Mineral Resources estimate at El Pachón, to a total of 2.740 billion tonnes at a grade of 0.48% copper using a cut-off grade of 0.2% copper. This represents 13.1 millon tonnes of contained copper metal, a 44% increase compared to the previous mineral resource issued 1 October 2010

Since acquiring El Pachón project in August 2006, Xstrata Copper has worked in full compliance with all applicable regulations to update the feasibility study and undertake comprehensive scientific and technical studies, in consultation with international experts and institutions, to determine the potential environmental impacts of a future mining operation at El Pachón. These studies will form part of the project’s Environmental Impact Study and include analysis of water and waste management; terrestrial and aquatic biodiversity; mine closure and rehabilitation together with investigations into permafrost and other manifestations of snow and winter ice in the El Pachón project area.