Mine closure and residual risk: a geochemical perspective

Speaker: Associate Professor Mansour Edraki, Principal Research Fellow, Group Leader - Environmental Geochemistry

Abstract: In Queensland, the Financial Provisioning Scheme (FPS) under the MERFP Act 2018 requires payment as part of final site surrender to cover rehabilitation of mining disturbed lands and any ongoing liability for the state, including exposure to residual risks. The EA holders are required to provide a final rehabilitation report, which includes a proposal outlining the cost of managing any residual risks in the form of Estimation of Rehabilitation Costs (ERC).

However, the complexity of scientific definition of residual risk for waste storage facilities and final voids, variability between different mine sites means that “one size doesn’t suit all” makes it difficult to implement a legislated reform to mine closure and rehabilitation, and seems to be a stumbling point to both transitioning sites to closure and lease relinquishment and also investment in rehabilitation. This challenge is not unique to Queensland, but the recent legislation has triggered an interesting discussion among researchers and professionals who have been working in this area.

In this webinar, Mansour will use examples of SMI projects to discuss some of the basic geochemical processes that we need to understand in order to predict and reduce residual risk at closure. The focus will be on acid and metalliferous drainage, including neutral and saline drainage.

Bio: Mansour joined UQ in 2000 following completion of his PhD at University of New England. Prior to that, and before immigrating to Australia in mid 1990s, he was a lecturer in earth sciences. Mansour's research interest is in understanding and predicting the source, transformations and fate of contaminants, particularly acid and metalliferous drainage (AMD), in the mining environment.

Mansour has initiated a number of international research collaborations including in Indonesia, Iran, PNG, the Phillipines, Korea, Peru and Chile, and coordinating the ‘Environment, Tailings and Water’ line of SMI’s International Centre of Excellence in Chile (SMI-ICE Chile).