As part of BHP Billiton Iron Ore’s plans to develop the Western 5 pit at its Yandi site over the course of 5 years, the diversion of a local creek and the creation of 3 flood bunds were needed to ensure that the site was capable of withstanding a 100 ARI flood event.
Austral was contracted to perform the earthworks necessary to achieve this goal.
The creation of a diversion drain required the stripping and stockpiling of 150mm of topsoil with 30T and 50T excavators, while allowing for periodic dust suppression from a water cart. The majority of the excavation continued after another party was brought in to blast the area and expediate excavation of the diversion.
The creation of the bunds required a 16m grader to clear and grub the footprint of each individual bund, before excavators were brought in to remove a 150mm layer or top soil like what had been done with the diversion. Common fill was then hauled in with a 40T Moxy loader and moved into place by excavator’s to achieve the desired RL, with geofabric placement and rock armour as per design specifications