Deep in the heart of the Cadia Hill goldmine, 1.4km below the surface, heavy machines dump loads of ore into a crusher. On the wall next to the crusher is a ventilation grate, which draws the dust in to a filtration plant and out of the mine’s main vent, “vent rise outlet 8”.
Until May this year, the emissions were vented straight from the ore crusher into the atmosphere. Newcrest, which owns Cadia Valley Operations, has since installed two “bag houses” that catch up to 1 tonne of dust an hour each when operational. The second bag house only came online last month.
