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Mining
The Aguas Blancas mine commenced operations at the end of 2000, and the first iodine was produced in April 2001. The open pit operations have a single high bench, taken down in variable heights according to the depth of the principally economic caliche material. An initial layer of chusca, approximately 0.5m, is initially stripped off using a bulldozer and accumulated at the sides of each mining block. Up to the end of 2005, the caliche material was broken up by drill and blasting operations. However, since February 2006 the caliche has been broken up by a continuous miner. The principal difference is in the size of the product, with the continuous miner mostly producing less than 6 inch material. It also cuts much more accurately to the caliche boundaries, producing a dramatic reduction in dilution.
Since 2000 and up to the end of 2010, the broken material has been hauled to heap leaching pads, with an average hauling distance of approximately 1km. The average overall recovery from heap to finished product has been about 58%. The finished product is +99.9% Iodine in a solid crystalline form (prills) and is sold in 50 kg drums. Sirocco is currently putting an agitated leach plant into production, which should achieve an average overall recovery of 78%. At the moment plans to produce sodium sulphate from the brines have been shelved, but the company is considering production of potassium nitrate, sodium nitrate or mixed nitrate salts.
Power is supplied through the local power grid. The connection point is located 28 kilometers northeast of the Aguas Blancas mine and consists of two new substations and a 69 kilovolt transmission line.
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Trencor Continuous Miner Machine
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Ore Loading onto Heap Pad
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