Chilean president Sebastian Pinera cut the ribbon at the inauguration of the Chuquicamata underground mine of Codelco, at Antofagasta, Chile, last month. After 104 years of opencast mining, the world's largest pit mine became a high-tech underground operation to meet the higher environmental and safety standards of the 21st century. At the ceremony, Codelco head Juan Benavides committed the company board to reposition Codelco among the most competitive, sustainable and profitable copper producers in the world.