The Importance of Progressive Rehabilitation in Australian Mining
In recent years, the Australian mining industry has made notable progress in meeting social and environmental responsibilities, particularly through the growing emphasis on progressive rehabilitation plans at active mine sites. This shift reflects a positive change, integrating environmental restoration as a continuous part of mining operations rather than a final step.
These sustainable practices represent a sharp contrast to historical mining approaches, which often left behind a legacy of abandoned, environmentally compromised sites. Australia now hosts approximately 80,000 inactive mines, many dating back to the gold rush era of the 1850s—a period of rapid economic growth that helped build cities like Melbourne but left a lasting environmental impact.
Without regulations for mine rehabilitation at the time, many sites were deserted after resource extraction, resulting in persistent environmental issues today. These abandoned mines contribute to dust pollution, soil erosion, and waterway contamination from heavy metals and other pollutants, underscoring the critical importance of current sustainable practices in the industry.
The enduring impact of abandoned mines underscores the critical need for ongoing rehabilitation. In regions impacted by historical mining, state governments continue to address the environmental legacies left behind, undertaking complex and costly remediation projects. These efforts often involve removing toxic materials, stabilising mine tailings, and restoring natural habitats.
Proactive rehabilitation is essential—not only for addressing immediate environmental risks but also for supporting the long-term ecological health of areas surrounding mining sites. The industry’s commitment to reducing its environmental footprint is evident in the mandate for progressive rehabilitation practices at all active mine sites, ensuring responsible land use and sustainability.
Water Management Challenges in Mine Closure
Water-related issues are among the most severe environmental impacts following mine closures, with effects that can persist for decades or even centuries. When mines cease operations, a lack of ongoing management can lead to the build-up and release of contaminated water, posing significant risks to nearby ecosystems and communities. A major concern is acid mine drainage (AMD), a reaction where sulphide minerals in exposed rock surfaces interact with air and water to produce sulphuric acid. This acid then leaches heavy metals from the surrounding rock, creating a toxic mix that can pollute nearby rivers, lakes, and groundwater.
An example highlighting these issues is a 2017 study by Dr. Ian Wright, a prominent Australian water scientist. His research on the Berrima Colliery, an abandoned coal mine in New South Wales under ‘care and maintenance’ since 2013, revealed that the site was releasing roughly 30 litres of heavy metal-laden water per second into the Wingecarribee River—equivalent to an Olympic-sized pool of toxic water discharged each day. This study underscores the ongoing challenges posed by water contamination at closed mine sites.
The water discharged from the Berrima Colliery contains dangerously high concentrations of heavy metals, including zinc, nickel, and manganese—elements known to harm human health and aquatic ecosystems. For example, zinc levels are more than 120 times the normal baseline, posing a serious threat to the river’s ecological balance. These contaminants degrade water quality and accumulate in the river’s sediment and organisms, leading to lasting ecological damage.
The impact of this contamination goes well beyond the immediate environment. As part of Sydney’s drinking water catchment, the Wingecarribee River could affect the health of millions relying on it as a water source. Local fishing communities are also concerned, as heavy metals bioaccumulate in the food chain, affecting fish populations essential for nutrition and livelihood. Contaminated fish present direct health risks to consumers who may unknowingly ingest toxic substances.
This case highlights the potential long-term impact of mining on water resources, underscoring the need for robust water management and treatment in mine closure plans. Without such measures, abandoned mines could continue to threaten public health, ecosystems, and local economies for generations.