MINING SERVICES
OPPORTUNITY TO IMPROVE MINE CLOSURE AND REHABILITATION Through collaboration and knowledge sharing, Australian mining can continue to protect the environment when projects close – and leave a positive legacy for communities.
T
he global mining industry is yet to fully understand the magnitude of failed mine site closures. Companies need to develop multi-disciplinary skills to better identify, measure and manage closure risks, and share learnings from successful and unsuccessful site closures. That is the view of Katina Strelein, a principle mine closure consultant at SRK Consulting. “Failed mine closures are a significant long-term risk for mining companies,” says Strelein. “Site-remediation costs can last decades or centuries, and be far greater than expected.” Energy Resources of Australia’s (ERA) problems with rehabilitating the Ranger project area reinforce the risks in mine-closure planning. In October 2021, ERA announced “material” cost and schedule overruns in Ranger’s closure and rehabilitation.
Ranger is Australia’s longest continually operating uranium mine. Located on Aboriginal land and surrounded by (but separate) from Kakadu National Park, Ranger has been a complex project to close. Final site rehabilitation, at this stage, is expected by January 2026. “Cost blowouts at rehabilitating Ranger should encourage the mining industry to increase its focus on mine-closure analysis and implementation,” says Strelein. “Despite all the planning, ERA is still struggling to understand what is required to successfully close Ranger.” Strelein recently wrote a paper on the early lessons of cost closure overruns at Ranger - Australia’s most studied mine on rehabilitation and closure. “Ranger’s problems reinforce the complexities of understanding mineclosure risks, their potential costs and over what period those costs will be borne,”
Strelein continues. Other Australian mines have had closure problems. The old Mount Morgan gold mine in Central Queensland is predicted to generate acid mine drainage problems for up to 500 years. The mine’s full rehabilitation is expected to cost hundreds of millions of dollars, possibly more . United States mines have also had closure problems. Some superfund sites (abandoned waste sites) have had problems because of misunderstood and managed geochemistry. Strelein believes mine-closure risks will increase this decade. “A large number of mines built in the ‘80s and ‘90s in Australia will likely close this decade. Some could face very costly problems. The United States is ahead of Australia in terms of the increase in mine closures, and the early evidence suggests many mines there have had rehabilitation issues,” she says.
A rehabilitated tailings dam with vegetation.
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