Mina Ministro Hales is Codelco's most recent project development and started in November 2013. It is located close to Codelco’s Radomiro Tomic and Chuquicamata operations. The project comprised an open pit mine, a 50 kt/d mill to produce 163 kt/a Cu and 287 t/a silver over a 14 year mine life. The ore contains significant amount of arsenic (around 1.6-1.9% As) that results in production of concentrate with As content just above 4%. To reduce the As levels, a 550 kt/a fluid-bed roaster was constructed to safely process copper concentrate and recover arsenic for further confinement. In addition to calcine and sulphuric acid, the roaster produces flue dust (around 4% volume) containing 22% Cu.