Three years ago, amidst growing concerns about the environmental impacts of mining, Associate Professor Anita Parbhakar-Fox embarked on an ambitious journey. She envisioned a transformative approach to mine waste, a concept that would not only redefine how waste is managed but also highlight its potential value.

This vision led to the establishment of the Mine Waste Transformation through Characterisation (MIWATCH) team at the Sustainable Minerals Institute, University of Queensland, in 2021.

The team, now 14 researchers strong, is dedicated to revolutionising the management of mine waste in the mining industry. According to Professor Parbhakar-Fox, the team’s fundamental philosophy is “We see waste not as a liability but as an asset. We saw an opportunity to change the narrative around mine waste and the potential for these materials to be valuable resources”.

MIWATCH’s primary goal is to aid the mining industry in achieving net-zero, including net-zero mine waste. The team focuses on determining the critical metal and mineral content in mine waste and viewing these materials as potential resources rather than mere byproducts. The characterisation methodologies developed by MIWATCH can be applied throughout the life of a mine, enhancing the understanding and management of waste materials from the outset.

The ultimate vision, as Professor Parbhakar-Fox explains, involves “fingerprinting waste from the start,” which could significantly aid in reprocessing decisions without needing extensive new drilling. However, she acknowledges that this dream is “probably still a decade or so off from being routine practice”.

Building on years of experience in the mine waste sector and geosciences, the MIWATCH team employs a range of innovative tools and techniques.

These include field-portable laser-induced breakdown spectroscopy, which can identify light elements such as lithium that other field-portable technologies cannot. The team’s integrated characterisation package, known as the ‘Stream 1’ program, has been implemented across about 70 sites nationwide.

This integrated approach allows the team to efficiently assess critical mineral potential and identify reprocessing options for mine waste at various scales, from environmental geophysics to synchrotron-based studies.

This year marks a significant period for MIWATCH as they conclude major research projects with several state governments and Geoscience Australia.

A notable milestone includes the completion of their program with NSW, covering 21 sites, with results to be published later this year. The team has also undertaken five ‘Stream 2’ projects, involving more detailed sampling and additional metallurgical test work, and has established new partnerships for testing novel ways to recover critical metals.

A highlight for MIWATCH was hosting the inaugural Australian Mine Waste Symposium at the University of Queensland, which brought together 160 individuals from industry, academia, government, technology companies, and students.

“This was truly a testament to the impact of our research,” said Professor Parbhakar-Fox.

One of the recent breakthroughs in MIWATCH’s research involves the application of geophysical technologies to better understand mine waste sites. This includes drone-based magnetic surveys and induced polarisation methods to delineate metallic sulphides containing critical metals. These technologies enhance characterisation programs by providing comprehensive site maps, enabling more selective and targeted re-mining efforts.

However, the team faces challenges, particularly with mine waste sampling. Tailings dams, for instance, pose safety risks related to liquefaction and dust, and can be difficult to sample deeply with hand augers. To address these challenges, MIWATCH is considering more efficient and automated sampling methods to optimise data collection while minimising risks.

MIWATCH’s work not only aims to transform mine waste management but also benefits local communities around mining areas.

By demonstrating the commercial value of mine waste, the team hopes to incentivise its repurposing, thereby reducing environmental risks and stimulating economic development. For example, their work at the Zeehan slag dump in Tasmania helped to inform its reprocessing for zinc extraction, removing environmental hazards posed by zinc, cadmium, and lead.

Additionally, MIWATCH’s characterisation of sites in Western Tasmania, Central and Northeast Queensland where mining communities had been historically established, aims to stimulate re-commercialisation, potentially stimulating local economies and providing job opportunities in former mining communities.

With an estimated 50,000 mine waste sites in Australia alone, MIWATCH’s role in transforming waste into valuable resources is set to expand.

Looking ahead, Professor Parbhakar-Fox envisions significant growth in the sector of mine waste management, driven by the industry’s changing approach and the increasing demand for critical metals.

Professor Parbhakar-Fox reflected on her journey and the impact of MIWATCH’s work so far.

“As a geoscientist, I was inspired to put my skills to good use to deal with two, maybe three, of the worlds wicked problems, namely climate change, waste management, and acid and metalliferous drainage (once named by the UN as the second biggest environmental challenge facing the global community after climate change).

“At the Sustainable Minerals Institute, I get to work with social scientists, chemical engineers, biologists, metallurgists, the technology sector, government and industry as well as a whole range of academics. But most importantly, I have the privilege of leading a team of talented early career researchers, who, like me, have the desire to put their geological training and engineering skills to good use and create a better future for generations to come.

“Hearing others in the industry say words like ‘net zero mine waste’, ‘economic rehabilitation’ ‘secondary prospectivity’ and even ‘Stream 1’ and explain these very terms to me, shows MIWATCH, who very much have introduced and championed these terms, have had an impact on the culture of mine waste management, showing that our research is already having an impact.

“If we change industry behaviour now before we go into a period of intense mining to deliver on critical mineral quotas needed for the energy transition, then we have a real shot at actually changing the industry’s approach to mine waste management.

“We are committed to net-zero mine waste and it’s the focus of my career to help make this happen.”

The Mine Waste Transformation through Characterisation (MIWATCH) project represents a groundbreaking approach to addressing the environmental challenges posed by mining waste. For more information on MIWATCH and its research, visit the Sustainable Minerals Institute at the University of Queensland website. https://smi.uq.edu.au/