Mining Still Seeking Solutions to Tailings Dangers
The mining industry continues to face mounting pressure to address the challenges of tailings management, a critical aspect of mineral processing that generates vast quantities of waste material.
Tailings, the residual material left after extracting valuable minerals from ore, require storage facilities that can span several square kilometres.
These facilities demand precise engineering to prevent environmental contamination and structural failures. The construction process involves creating containment structures that must withstand extreme weather conditions and maintain stability over decades.
The 2019 Brumadinho dam disaster in Brazil brought tailings management into sharp focus. The collapse of Vale's tailings dam resulted in 270 fatalities and widespread environmental damage.
Eduardo Bartolomeo, CEO of Vale, the Brazilian mining company, says: "In the aftermath of Brumadinho, we've significantly increased our focus on tailings management. We've implemented more stringent monitoring systems and are accelerating our transition to safer technologies."
Modern tech transforming tailings operations
The industry has developed new approaches to tailings storage. Traditional methods relied on wet storage, where waste material mixed with water forms a slurry. Modern techniques focus on dewatering tailings before storage.
Suzanne Retallack, Chief Safety & Sustainability Officer at Newmont Mining, a US-based gold producer, says: "The industry is moving towards filtered, dry-stack tailings facilities. This method produces a filter cake with 85% solids content."
This transition reflects broader changes in mining practices. High-pressure filtration systems remove water from tailings, creating more stable storage conditions.
Jonathan Price, CEO of Teck Resources, a Canadian mining firm, says: "We're investing heavily in new technologies like high-pressure filtration and dry-stacking to minimise risks associated with conventional tailings dams."
BHP and Anglo American drive sustainability initiatives
The mining sector recognises tailings management as central to sustainability efforts. Waste facilities can impact water resources, land use, and local communities.
Tom Butler, CEO of the International Council on Mining and Metals, a London-based industry association, says: "Sustainability in tailings management ensures long-term viability of operations and maintains our social licence to operate."
Mark Cutifani, former CEO of Anglo American, a multinational mining company – and currently Senior Independent Director with Laing O'Rourke – says: "The Brumadinho dam disaster was a wake-up call for the entire mining industry."
Companies are now exploring methods to extract additional value from stored tailings.
Mike Henry, CEO of BHP, the Australian mining corporation, says: "The future of tailings management lies in embracing circularity. We're exploring ways to reprocess tailings to extract additional value."
Current global tailings facilities include the Grasberg mine in Indonesia, storing over 1 billion tonnes of tailings. The Ok Tedi mine in Papua New Guinea manages 2 billion tonnes of tailings material.
Tailings monitoring systems
The industry continues to develop new technologies and practices. Monitoring systems now include satellite technology, drone surveys, and real-time sensor networks to detect potential structural issues.
In 2020, the ICMM set out to establish an international standard for the safe management of tailings storage facilities.
Co-convened by the Principles for Responsible Investment (PRI) and the United Nations Environment Programme (UNEP), the standard is applied to all tailings dams – wherever they are located and whoever operates them.
The review was set up in response to the Brumadinho tragedy in Brazil, and was informed by evidence and lessons from that disaster, as well as earlier mine tailings dam failures.
