By Chris Rochfort, CEO, Centre for Organic Research & Education

With growing global demand for minerals such as coal and iron ore, as well as precious metals and rare earth elements, greater emphasis is being placed on water’s role in maintaining consistent and sustainable operations.

Mining operations have a deep relationship with water, whether it is managing excess rainfall and process water, or sourcing water for processing activities and worker accommodation camps.

The management of onsite holding ponds has become increasingly challenging due to intensified rainfall events experienced over recent years. These extreme weather events result in increased sediment loads being captured by holding ponds, significantly reducing their water-holding capacity during heavy rainfall periods.

Regulatory requirements and consent conditions are tightening, potentially restricting mine site operations further. Achieving zero carbon emissions, and meeting environmental, social and governance (ESG) goals are now priorities for shareholders and communities alike.

This has increased attention on sediment control measures, and effective water protection and treatment systems, particularly at holding pond outlets. Capturing and treating excess flows during wet periods can also provide supplementary water resources, enhancing water reuse capabilities during drier spells.

Nature-based solutions

The adoption of nature-based solutions, which require no mechanical or chemical inputs, is gaining momentum as a cost‑effective and sustainable approach to addressing these complex challenges. Research by institutions like The Centre for Organic Research & Education highlights how recycled organic materials such as food organics and garden organics (FOGO) can effectively manage and treat surface water flows, providing reusable water of a high quality. These organic materials demonstrate remarkable efficiency in removing metals, nutrients, sediments and complex compounds such as hydrocarbons.

Specific solutions gaining popularity include filter berms and reactive filter media. Filter berms are engineered barriers filled with innovative reactive Filter media, and are designed to capture and treat stormwater run-off at source points. These berms effectively remove contaminants and sediments, significantly enhancing water quality prior to discharge or reuse. Reactive filter media, a specialised filtration medium, facilitates high removal rates of pollutants through physical filtration and chemical interactions, improving overall environmental outcomes.

Filter berms, for instance, are particularly beneficial due to their ease of installation and maintenance. They can be strategically placed in areas prone to high run-off, such as around construction sites, roadsides, and industrial facilities, making them versatile tools for environmental protection. By capturing sediments, hydrocarbons and other contaminants before they enter waterways, these berms significantly reduce the risk of pollution and improve overall water quality.

Reactive filter media is also widely recognised for its high performance in pollutant removal. This specialised media can be custom-designed to target specific contaminants, such as heavy metals, phosphorus, nitrogen and various organic pollutants. The media utilises both physical filtration mechanisms and chemical processes, such as adsorption, precipitation and microbial degradation to achieve high removal efficiencies. As a result, this innovation has proven itself to be sturdy and effective across stormwater management systems, bioretention basins, and biofilters, providing a sustainable and reliable treatment solution.

One Australian organisation in particular – STAR Water – has positioned itself at the forefront of sustainable water management through its patented advanced biofiltration technology and bioretention systems. The Sydney‑based company’s innovative systems are designed to effectively manage stormwater run-off and treat various pollutants efficiently.

STAR Water’s solutions utilise recycled organic materials, aligning with circular economy principles by repurposing waste products like FOGO. This not only aids in waste reduction, but also provides a renewable resource for water treatment applications.

The company has previously assisted mining operations including Centennial Coal and Lake Coal in New South Wales, together with the Gympie Gold Mine in Queensland.

Mining benefits

The economic benefits of adopting these nature-based solutions are significant. Implementing sustainable water management systems can substantially reduce operational costs associated with traditional water treatment and disposal methods. Moreover, treating and reusing water onsite decreases dependency on external water sources, further reducing operational expenditures. Environmentally, these solutions contribute to preserving local water resources, enhancing ecosystem health and improving community wellbeing.

Research by STAR Water has indicated that coal mining producers’ residuals from tailings contain around 60 to 80 per cent carbon. These tailings can be used as a component in STAR Water’s water treatment filters, potentially helping to create carbon offsets, along with protecting waterways and providing the coal industry with an ESG opportunity.

For miners, the benefits include access to a low-cost carbon source, offering up to a 50 per cent saving on conventional organic materials. The process can also reduce chemical fertiliser costs in rehabilitation by up to 80 per cent, a significant saving. It can also increase moisture holdings by up to 100 per cent, reduce water contaminant emissions by 90 per cent and lower water run-off by 50 per cent, while saving $5 per tonne of carbon credits (based on an Australian Carbon Credit Unit Scheme price of $16.94 per tonne).

Other benefits to coal miners from STAR Water’s process include the opportunity to beneficially use coal residuals for financial return, reducing acid mine drainage impacts by up to 79 per cent; and providing supplemental components for building top soil, reducing the cost of transporting soil by up to $100 per tonne.

Additional benefits include increased plant establishment rates by up to 364 per cent, reduction in plant mortalities by up to 50 per cent, reduced sentiment in run-off by up to 90 per cent and reduced sediment control costs by up to 50 per cent.

In summary, addressing modern water management challenges requires innovative, sustainable solutions, many of which are available for implementation right now. The integration of nature‑based systems such as filter berms and reactive filter media represents a promising future, showcasing technology‑driven, environmentally conscious solutions that can effectively tackle these issues, ensuring regulatory compliance, reducing environmental impact, and delivering tangible economic and ecological benefits to the mining industry.