Domes over the 7th Largest Copper and Moly Development
Keeping the environment safe from impacts of stored copper ores as well as minimising material losses due to deflation were the main reasons for building two storage domes at a newly developed copper and molybdenum mine in Northern Chile. Covering stockpiles under the harsh regional conditions would have been a monumental challenge in years past.
Sierra Gorda, a community in the Antofagasta Province of far north Chile, sits in the Atacama Desert 1,700 meters above sea level. The arid landscape evokes an otherworldly mystique complete with sand, salt lakes, felsic lava and stone. As the driest non-polar desert in the world (and possibly the oldest), it boasts a sweeping terrain stretching 1,000-kilometers west of the Andes. With a population of less than 2,000, this remote region has gained a surprising amount of global attention. Sierra Gorda’s desolate beauty became an ideal setting for scenes included in the Quantum of Solace movie starring Daniel Craig, a 2008 James Bond thriller. But what lies beneath the landscape may be more impressive, as Sierra Gorda’s brush with celebrity pales in comparison to the ongoing achievements of the Chilean mining industry.
Sierra Gorda Sociedad Contractual Minera (Sierra Gorda SCM) is acclaimed as the seventh largest copper and molybdenum development on planet earth — a distinction demonstrating the demand for copper, the strength of copper prices, and the dominance of northern Chile as a coveted copper producing region. In fact, Sierra Gorda is a joint venture between KGHM International, Sumitomo Metal Mining and Sumitomo Corp., and has successfully intertwined the economies of three countries: Chile, Poland and Japan.
Concentrate was first produced in July 2014, followed by an opening ceremony October 1 attended by dignitaries from the Republic of Chile headed by President Bachelet, the Republic of Poland government, the Japanese government, as well as representative construction and operational partners. In December the mine produced approximately 700 daily tons of concentrate. According to KGHM Polska Miedź, production will ramp up to 120 000 metric tons of copper, 50 million lbs. of molybdenum and 60 000 oz. of gold annually.
An Eco-Friendly Dome-Duo
Certainly, sustainable mining principles with regard for surrounding eco-systems is a foremost concern at Sierra Gorda’s open pit mining operation, which encompasses crushing, grinding, flotation and drying processes. Herbert Wirth, President and CEO of KGHM, noted the company’s uncompromising respect for people and constant dialogue with local communities, along with modern methods and management systems to responsibly extract and process copper ore and other resources. Maciej Ściążko, General Manager of the Sierra Gorda project, stated that the mine will help feed the demand for copper and molybdenum around the world, as well as provide local jobs for years to come as a great employer and a great neighbor.
Copper and molybdenum ore and concentrates require special storage solutions. It was imperative that the storage buildings safeguard nearby habitat from air, particulate and water pollution — a principle mandated by all the parties involved. Based on its robust portfolio of applications throughout the Andes, Geometrica was hired to provide ore and concentrate storage for the Sierra Gorda project. Two circular domes were designed to store the stockpiles while protecting the surrounding flora and fauna, including indigenous foxes, birds, lizards and geckos.
Internal cladding protects the 62m building from a stockpile of concentrate.
One application spans a remarkable 122 m over the copper ore stockpile — an immense structure longer than a football field. A second dome, for concentrate, spans 62 m and was welded to embedded plates on a retaining wall. It features internal cladding to protect the galvanized steel structure from any possible corrosive attack by potentially humid copper concentrate stored within the building.