Client: Rio Tinto | Location: Pilbara, Western Australia
Global were contracted for work at Rio Tinto’s Nammuldi Iron Ore project during 2008/2009, with a goal to mine previously inaccessible, abandoned Ore located below the water table. The pit was subject to a dewatering scheme, and a Wirtgen 2500SM then used to create a stable floor with a 3% cross-fall to an integrated perimeter moat.
This allowed full access to the pit at all times, and the material to be progressively milled flitch-by-flitch while keeping the water level below the current floor. Contour mining along the BIF present in the adjacent ridgeline maximised the recovery, and material was able to be graded on the fly, minimising processing and rehandling costs. The Wirtgen 2500SM achieved productivity levels of up to 900t per hour and the additional resource was recovered at a very low cost.