A substantial majority of the people from the eight sectors of the Michiquillay community approved the social agreement at a meeting on June 3, 2008. The La Encañada community voted in favor of the agreement on May 23. Issues addressed by the agreements include sustainable development, with provision for establishment of a community development foundation, and environmental issues, with provisions for creation of participative monitoring committees and completion of an environmental base line study and a detailed study on soil usage before starting exploration activity.

Michiquillay is a large porphyry copper exploration project located 35 km east of Newmont-Buenaventura’s Yanacocha gold operations. Asarco discovered the deposit in the late 1950s and conducted exploration work on it from 1959 to 1965. From 1972 to 1976, a Japanese-controlled company, Michiquillay Mining, conducted additional exploration work and completed at 40,000-mt/d feasibility study. Historic exploration work on the property has included 159 diamond drill holes totaling 41,600 m and underground tunneling totaling 2,500 m.

The Peruvian government has estimated Michiquillay reserves at 544 million mt, grading 0.69% copper, more than 0.1 g/mt gold, and more than 2 g/mt silver, using a 0.40% copper cutoff. Anglo American believes that the deposit has significant additional exploration potential.