Pollution: The use of highly toxic mercury to separate gold from ore is illegal because it remains in the environment for a long time, cycling between the air and soil. Photo: Delwyn Verasamy
When Mariette Liefferink was invited to join the Directorate for Priority Crime Investigation (the Hawks) in May on an operation targeting illegal artisanal mining in Zuurbekom, an agricultural and residential area in Gauteng’s West Rand, she couldn’t believe what she saw.
Liefferink, the chief executive of the Federation for a Sustainable Environment, was confronted by illegal gold reprocessing activities using cyanide to leach the gold from the crushed ore.
It illustrated the hazards of illegal mining. “Besides the risks to human life, health and wellbeing, illegal mining can have devastating impacts on surface and groundwater resources, air quality and sensitive and protected ecosystems,” Liefferink said.
Cyanide spills into groundwater can persist for long periods of time and contaminate drinking water aquifers, she said. “There were no safety precautions at the reprocessing and leaching facility to minimise the risks … as well as management measures to prevent possible spills of cyanide containing solutions into the agricultural and residential environment.”
Three unlawfully constructed dams were used for the reprocessing of gold-bearing material. In one of the dams and its outlet, laboratory results showed the cyanide levels — free cyanide and weak-acid dissociable cyanide (WAD) — were 428 milligrams per litre (mg/l) and 798 mg/l, respectively.
The limit for WAD in terms of the protection of birdlife, cattle and wildlife is 50 mg/l. According to the International Cyanide Management Institute and the World Bank’s standard, the limit for free cyanide is 0.01mg/l.
During the Hawks’ operation, about 1 260 tonnes of gold-bearing material with an estimated value of R3 million was found buried underground.
“Only one illegal miner was apprehended — a 22-year-old illegal immigrant from Zimbabwe — but the kingpins escaped,” Liefferink said.
Trucks from Sibanye-Stillwater mining company were used to remove all the contaminated soil from the sites and to transport it to the company’s licensed sites. “The impacts of the illegal operations on the soil, air, ground and surface water were not assessed or, if it was, we were not informed. I am not aware any rehabilitation of the contaminated sites was done.”
According to the Minerals Council South Africa, the environmental impacts of illegal mining include sabotaged pipelines that contaminate the environment, illegal water usage and wastage, sinkholes created from water pipeline “spiking”, underground fires and explosions, mercury contamination of the environment and the excavation and reopening of sealed and rehabilitated shafts, with associated hazards.
Marcos Orellana, the United Nations special rapporteur on toxics and human rights, said the use of mercury — a highly toxic metal — is illegal in mining activities.
“However, it is still used by illegal small-scale miners commonly known in South Africa as zama zamas. Interlocutors explained that some zama zamas can be characterised as criminal syndicates, while some others are often pushed to such mining due to lack of alternative employment,” Orellana said.
A November 2022 report by parliament’s portfolio committees on mineral resources and energy, home affairs and the police said there were more than 6 100 abandoned and unrehabilitated mines in the country.
“With the current pace and small budget allocation for the closure and rehabilitation of these mines, it would take government over 16 years to close these mines. In the meantime, these mines are used by the illegal miners for illegal mining,” it said, noting that illegal mining also occurs in legal mines.
Liefferink said mines under care and maintenance, and the abandonment and liquidation of mining companies results in the failure to make the areas safe and rehabilitate them, implement access control, and manage and mitigate the risks and hazards on the Witwatersrand gold belt — and the proliferation of illegal mining.
Illegal mining affects infrastructure because illegal miners use water from sewage pipes and water pipes for the processing of the gold.
Urban sprawl and the encroachment of informal and formal housing onto mine properties exposes communities to illegal mining activities.
“Since the gold ore co-occurs with uranium and its radioactive property, illegal mining can result in the dispersal of radioactive material within the environment,” Liefferink said. “Due to the presence of sulphide-bearing material, illegal gold mining within the Witwatersrand goldfields can also contribute to acid mine drainage.”
The portfolio committees’ report said illegal mining often causes structural damage to the ground, leading to permanent road closures because of sinkholes, cracking and caving-in of the surface ground from uncontrolled underground digging.
The Mogale City local municipality said illegal mining was a “thorny and challenging issue” because it “threatens the security of our residents, business community as well as the safety and longevity of our infrastructure”.
“Overall, all these aspects will in the long run negatively affect the municipality’s ability to deliver on its core mandate — the provision of quality and reliable basic services to constituencies that we are mandated to serve, especially those directly under threat such as water and local roads.”
In April 2022, Windsor Road collapsed because of illegal mining activities underground in the area. “This was a result of shallow underground tunnels dug by illegal miners under municipal roads. Although the required reparation work was done on the road, it collapsed again earlier this month due to identical reasons and remains closed.”
Illegal miners have also exposed an underground bulk water supply pipe belonging to Rand Water. “Once this risk was discovered our bulk water supplier was immediately made aware of this threat. They have since assumed the responsibility for it, such as repairs and costs.”
A September 2022 report by the Global Initiative Against Transnational Organised Crime describes how, in Johannesburg, underground blasting by zama zamas near gas and fuel pipelines has become a “major public safety issue”.
“One particular site of concern lies beneath the FNB soccer stadium in Soweto … where illegal miners are known to blast close to gas pipelines. Zama zamas have also eroded supporting pillars that were left intact in the days of legal mining, raising fears of dangerous collapses across the city: in 2021, several roads collapsed in the city’s southern suburbs due to illegal mining.”
Sasol spokesperson Alex Anderson said the energy and chemical company has “robust operational and risk management” to ensure the safe ongoing operations of gas supply throughout its network pipeline.
“We remain committed to working closely with all authorities and government stakeholders to ensure the safety of communities is prioritised in the locale of our gas pipelines,” Anderson said.