From December 2011 to July 2013, SRK carried out a prefeasibility engineering study for Andes Iron’s Dominga Norte and Sur project. The study included resource estimation, geotechnics, mine design and production schedule, Iron (Fe)-Copper (Cu) mineral processing, power and water supply, a reverse osmosis plant and slurry pipeline for pellet feed, a filter plant, copper concentrate production, tailings dam and port facilities. SRK also provided a NI 43-101.
The project, located 75km north of La Serena, Chile, in the Coquimbo Region, will pursue Fe and Cu through two open-pit mines. The combined proven and probable reserves for Dominga Norte and Sur are: 733 Mt at 25.6% FeT, 0.08%CuT and 0.01 ppm gold (Au).
The 23 year mine life is estimated with 34 Mt/y ore and 95 Mt/y waste.
The project will be divided into six main areas: mine pits and waste dumps; process plant; power supply; slurry and water pipelines; main port infrastructure, and tailings dam.
The north and south mine pits will produce 95 Ktonnes/day (34.4 Mt/year); the plant will produce 11.5 Mt/year of Fe concentrate and 120 Kt/year of Cu concentrate containing approximately 15 Koz/year of Au.
The plant area includes the primary crusher, stockpile, grinding plant, iron wet magnetic separation plant, copper concentration and filtration plant and infrastructure for thickeners, ponds and slurry transport. It contains Andes Iron´s administrative offices, construction camp, storage, laboratories, center for solid waste management, and a gas and diesel station. Power will be supplied by the Punta Colorada power substation.
In the piping area iron concentrate, water and tailings will be pumped into the process plant area, port area and tailings dam.
The port facilities consist of an iron concentrate filter plant, water dissipater stations, thickeners and pond conditioners, reverse osmosis plant and building, sea water ponds, treated water, brine and emergency ponds and general support facilities.
In the process plant area for example, the overburden was removed to construct the crushing area followed by assembling and filling the mechanically stabilised earth wall to its maximum elevation.
The iron magnetic concentration area was designed to bring together the particles of iron ore through low intensity magnetic concentration and reverse silica flotation. The copper flotation area was designed similarly to treat the tailings from the iron plant.
Key tasks included a pipeline to transport iron concentrate from the plant to the port, a pipeline to transport desalted water from the reverse osmosis plant, and a third to transport recovered water from the port to the plant.
