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Gold mining’s vice-like grip on the environment

Beyond the shiny end-product of the gold mining process is the unfortunate reality that traditional processing methods come with serious and widespread health and environmental risks.

Cyanide and mercury have been used in gold mining for more than a century and the pressure is on the industry to change as regulators move to ban toxic substances and producers look for safer, healthier ways to maintain production.

Clean Mining is using sophisticated new technologies to help drive a monumental industry change and its sights are firmly set on a world where toxic mining processes are eliminated, and where safe and responsible production simply makes good business sense.

Group CEO Kevin Fell said that cyanide leaching was still the mainstay of most commercial gold processing operations.

“It is promising that governments, miners and communities are becoming aware of the impact of poisonous chemicals and many are looking for new and better ways of working,” he said.

“Over time, miners are realising the massive costs associated with cyanide use, like regulatory compliance, health and safety, ancillary chemicals and acids, contingency plans and infrastructure, monitoring and reporting, tailing dam management, cyanide destruction and end-of-project remediation.

“Until now, environmental safety has come at a premium but Clean Mining’s technology is proof that you can achieve good economic returns and great environmental outcomes too.”

Some of the major environmental impacts of traditional gold processing include:

Water source contamination

It is estimated that more than 90% of the world’s gold is extracted using toxic chemicals like cyanide and mercury.

Most of the waste is stored in tailing dams, creating a very real threat of toxic chemicals escaping or leaching into ground and surface water. Several countries have already placed strict controls on the use of cyanide in mining and some have banned it altogether.

Both cyanide and mercury are poisonous, even at very low concentrations, so high concentrations of these chemicals in water supplies can be lethal. Just a grain-sized dose of cyanide, or 1.5 grams of mercury, is fatal to humans while trace amounts of cyanide can kill fish.

Mercury emissions

The artisanal and small-scale gold mining industry is the biggest source of mercury pollution on earth. These miners use mercury as an amalgam to retrieve gold, after which they heat the mixture, often with a torch or over a stove, to distil the mercury and isolate the gold releasing toxic vapour into the air.

Mercury can remain in the environment for thousands of years, posing an ongoing threat to the health of miners, ecosystems and communities.

Concerningly, mercury which makes its way into water sources is converted into a toxic organic compound called methylmercury which is even more easily absorbed into the body.

Habitat destruction

Tailing dams, which store the by-products of mineral processing, can be as big as lakes with walls up to 300 metres high. Large areas of land must be cleared to make way for these massive dumps which means a significant loss of habitat for native plants and animals.

Chemical leaching into the soil has the potential to change or destroy the ecosystem, impacting plant life with the build-up of heavy metals in the soil and vegetation ultimately entering the food chain.

If a tailings dam collapses, the environmental devastation is far-reaching with vast amounts of toxic waste expelled into the water, soil and air. There are an estimated 3,500 active tailings dams currently in existence, but no universal standards exist on how they should be built, maintained or decommissioned.

In the 10 years between 2007 and 2018, 27 serious tailing dam failures were reported across the mining sector, resulting in significant ecological damage and the loss of lives.

At long last, a solution

In June 2019, Clean Mining launched its revolutionary gold processing technology that replaces cyanide with an award-winning, sodium thiosulphate-based solution. This non-toxic solution eliminates a plethora of environmental issues with current gold mining practices—for example, it produces noticeably less tailings, with the potential to get rid of tailings dams entirely—and, better yet, is scalable, capable of addressing the needs of a wide range of mining operators.

It has also recently been proven to remove mercury, offering the only genuine remedy for miners and communities faced with mercury contamination in the artisanal and small-scale gold mining sector. Developed by Australia’s national science agency, CSIRO, the technology is the culmination of more than a decade of scientific research and market testing.

Clean Mining is part of the Clean Earth Technologies Group.

Source: Amazon Aid Foundation

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