You will require this approval if you intend to discharge ballast water from a vessel into a ballast water reception facility in Australia.
Ballast water is water that is taken on board by vessels to improve stability and manoeuvrability during transit. This water may contain pests, and unmanaged discharge could potentially introduce invasive marine species.
A ballast water reception facility means a facility, including a vessel, for receiving ballast water from vessels for treatment or disposal.