Our capabilities and expertise have developed and evolved over the years to meet the future knowledge needs of the sector and its stakeholders but broadly can be categorised into a number of key thematic areas.

Ecological Engineering and Rehabilitation of Mine Wastes

Tailings represents the most challenging and costly domains in mined landscapes of Fe-ore and base metals. The research aims to discover new knowledge of microbial driven bioweathering of tailings minerals and associated biogeochemical processes and develop new technology and methodology for rehabilitating metal mine tailings.

The emerging technology is significantly different from conventional rehabilitation technology (such as soil remediation, phytoremediation and soil-capping), which essentially treats the tailings as engineered parent materials (rather than “soil” per se) and harness in situ microbial power purposely primed and enhanced to accelerate mineral bioweathering and secondary mineral formation, which underpin the development of suitable physicochemical properties and biological capacity in expected technosols and/or hardpans. Recent Examples of projects included:

(2018–2021) Queensland Alumina Limited

(2017–2019) Rio Tinto Aluminium Limited

(2016–2019) ARC Linkage Projects

Ecosystem structure and function

Fundamental to the development of sustainable ecosystems post-mining is the requirement to align the properties and behaviour of the substrates and climate with the desired structural and functional attributes of the new target ecosystems.  SMI-CMLR research contributes to the development of rehabilitation indicators and completion criteria, developing methodologies to determine when rehabilitation is progressing on a trajectory to success.  Research considers factors that influence seed germination, substrate-plant relationships, roles of microbial and faunal assemblages, robustness and resilience to disturbance, and biodiversity values.  Recent examples of projects have included:

  • Increasing the scientific rigor of flora monitoring to improve the value and accuracy of data collected to increased confidence about the presence and level of potential impacts on listed upland swamp vegetation communities as a consequence of underground coal mining.
  • Assessing the structural and functional development of re-instated native plant communities following heavy mineral sand mining and their progression towards the target communities.
  • Understanding how developing ecosystems are influenced by external factors such as climate and fire, and how these impacts influence the trajectories towards agreed criteria.
  • Building monitoring designs that are robust, transparent and defendable with adequate power to detect ecologically significant changes in the species of interest, as well as informing adaptive management if putative impacts are observed.
  • Developing pre-mine monitoring techniques for assessment of listed flora species, endangered ecological communities, and threatened fauna groups encompassing both bird species (including migratory species) and cave-dwelling microbats.
  • Enhancing the management and conservation of koalas in areas impacted by mining during vegetation clearance through to specific habitat creation as a part of mine closure planning.
  • Linking biogeochemistry to the occurrence and spatial distribution of tolerant plant communities growing in naturally metal-enriched environments, and identifying metallophytes and hyperaccumulating species for potential use by the minerals industry.

Stable landforms and sustainable substrates

The topography of a landscape after mining can have a major impact on rehabilitation strategies.  Slope, elevation, aspect and drainage patterns all influence surface stability, erosion potential and land use options.  SMI-CMLR research on materials characterisation enables an understanding of, and amelioration strategies for, the chemical, physical and biological properties that may prevent landform stability and limit the establishment of sustainable ecosystems.  Recent examples of projects have included:

  • Improving the design criteria and performance of engineered covers that are constructed to reduce the potential of water infiltrating into potentially acid-forming mine wastes for climates with a high risk of seasonally high volume and high intensity rainfall events.
  • Developing a cellular automata run-off model as a simulation tool for assessing the hydrologic behaviours of different rehabilitation designs at spatial and temporal scales.
  • Investigating if findings from natural landscapes where ecological attributes and diversity is positively correlated with landform heterogeneity are valid in post-mining landscapes.
  • Testing efficient and accurate methods to quantify coal and black carbon in mine soils using thermal analysis and multivariate curve resolution so it is possible to calculate green carbon.
  • Investigating the effectiveness of amendment options for ameliorating primary constraints and restoring key soil processes for reconstructing root zones in base metal tailings.

Water and contaminants in the landscape

The characteristics of created landforms and substrates can have a major influence on the quantity and quality of water within a mined landscape.  An understanding of geochemical and hydrological processes through laboratory and field studies can assist the prediction and control of potential impacts under a range of climatic conditions.  SMI-CMLR research encompasses studies on contaminant mobilisation at and below the surface, in waters and sediments both on-site and downstream.  There is a focus on identifying contaminant transfer pathways and understanding risks to receptors at both ecological and human health scales.  Recent examples of projects have included:

  • Quantifying sources of lead and other metals and metalloids, exposure pathways and risks to environmental and human health of emissions from base metal mining operations.
  • Describing the hydro-geochemistry of tailings storage facilities to understand their long-term geochemical behaviour and potential effects of seepage on local surface and groundwater.
  • Developing advanced measurement techniques to overcome the uncertainty associated with metal and metalloid loads in waterways downstream of mining operations.
  • Demonstrating the relationship of bioaccessibility measurements with bioavailability of heavy metals in mine wastes and method validation with animal models to understand the risks and improve predictions of the likely chronic and acute effects on human health.
  • Synthesising and testing a series of surface-functionalised polymers to stabilise heavy metals and metalloids in the pore water of mine waste to facilitate the rehabilitation process.

Monitoring and mapping technologies

Gaining confidence in the success of mine site rehabilitation requires assessment of a range of spatially-explicit parameters such as vegetation cover and densities, biodiversity, growth rates, recruitment, salinity and erosion.  Using remote sensing techniques, monitoring of mine sites at temporal and spatial scales can identify changes in ecosystems and hydrological and landform processes with a high degree of confidence.  SMI-CMLR research uses remote sensing technologies and spatial analysis methods for the mapping and monitoring of pre-mining landscapes and rehabilitation throughout operational and post-closure phases.  Recent examples of projects have included:

  • Using Unmanned Aerial Vehicles to capture imagery at spatial and temporal resolutions higher than possible with satellite and manned aircraft to reliably indicate condition and composition within ecological communities based on sensitivity, structure and scale.
  • Provision of accurate information about the development of rehabilitation over time, including assessments of slope stability, erosion or slumping across sites.

Mine closure and end use planning

In order to achieve effective mine closure with minimal future risk to the environment, and maximal opportunities for a positive legacy, integrated and forward planning is an essential component of the mine planning process.  Preparing for successful mine closure from pre-operational phases across all aspects of the mining process will contribute to a reduction in negative environmental outcomes and result in more efficient and more economic closure strategies.  SMI-CMLR research uses a multi-disciplinary approach to explore options for developing sustainable end land uses and for identifying knowledge gaps that could impact on successful mine closure.  Recent examples of projects have included:

  • Developing strategies of integrated tailings management through using information on biogeochemical processes in the design of activities within mineral processing plants, upstream characterisation of ore and gangue, and downstream tailings management.
  • Developing a national abandoned/legacy mine hub as an opportunity to implement national policy and provide a pathway to address cumulative impacts, risks and opportunities.
  • Developing an approach for mined land end-use risk assessments using a Bayesian Network modelling framework and separate risk models for key hazards (e.g. erosion, fire, weeds).