South32’s Worsley Alumina Mine Expansion Revised Proposal covers the next phase of mining within the Worsley Mining Development Envelope, the Bauxite Transport Corridor linking existing and future mining areas, and a Contingency Bauxite Mining Envelope to ensure ongoing supply to the refinery. CDM Smith supported the complete Part IV approvals process, preparing the Environmental Review Document for public review and coordinating responses to more than 600 agency and community submissions. We worked with South32 to complete assessments for Matters of National Environmental Significance, undertake gap analyses, coordinate technical specialist inputs and draft Environmental Management Plans aligned with current EPA guidance. We also supported biodiversity offset documentation, strategic advisory, regulator engagement and peer review. As an accredited bilateral assessment, our work met both State and Commonwealth environmental requirements, supported by specialist groundwater modelling review from our Water Team.