Mining is still dangerous—but new tech in South Africa could keep workers safer
This article originally appeared on Undark .
Thabang ditibane spread his arms to describe the size and impact of the stone that killed a South African miner four-years ago.
“I heard a sound and turned around to see that the rock had smashed my head,” Ditibane, a rock driller at the Eland mine north of Johannesburg, said. Ditibane was standing in a 6-foot-high gulley lit by a string of snake-like lights as he spoke. Overhead, thousands of tons of rocks were visible.
The incident occurred at another mine. The rock had suddenly fallen into the tunnel. These accidental deaths, known as falls of ground or FOGs, are a major cause of death in South Africa’s mining operations. According to the Minerals Council South Africa, the main industry group in the country, more than 80,000 South African miners have been killed at work since industrial-scale extraction began in the late 19th century. More than 1,000,000 have sustained serious injuries. Despite improvements in the country’s performance over the past decades, the International Council on Mining and Metals, an industry group, says that its mines remain among the most dangerous in all of the world.
Labor union members want the industry to invest more in safety. The industry is not investing enough in safety and health. They are more interested in making profits,” Livhuwani Mammburu, spokeswoman for South Africa’s National Union of Mineworkers, stated.
Experts claim that South Africa’s mines have become less dangerous than they were in the past. Since the early 1990s, intensified regulatory scrutiny, labor activism, and investor pressure have driven the sector to mine more safely. The industry, labor organizations and the government have now declared zero harm as their goal.
Statistics show that there has been a sharp decline in FOG deaths this year. However, industry executives and experts agree that new technologies are necessary to achieve the goal of zero incidents. These include sophisticated radars that can detect ground falls before they happen. Experts believe that the new tools could reduce fatalities even further, based on the success of radars on surface mines to warn of impending landslides.
It is unclear how far these tools will go. Although the mining sector has indicated its willingness to invest in research and development, it is not clear how far these tools can go. However, costs will play a role in any company’s decision whether to adopt such technology. Geology can often bring out unexpected results underground, especially in South Africa where the mines are located at a depth of nearly 2.5 miles below the surface.
” We will accept any type of technology,” Mammburu stated, “that is meant for saving lives in the mining sector .”
A fall of ground is, as the name implies, a frightening prospect. The rock overhead suddenly falls. Mining-related disturbances and gravity can all play a part.
Bryan Watson, a rock engineer from Johannesburg’s University of the Witwatersrand, said that the rock mass is not as homogeneous. Instead, he explained, the solid mass appears to be riven by joints and gaps. Watson explained that Molten magma pushes upwards from the Earth’s center and exploits its weakness to push it apart. He explained that miners can dig beneath these fissures or areas of weak rock to create a “void” in which the rock can be thrown .
Foundations of natural earthquakes and small shakings from mining activities close to fault lines can also trigger FOGs. (Such seismic events can also cause a rock burst, in which pressurized rocks explode, propelling shards at up to about 20 miles per hour.) Watson stated that mining blasting can sometimes cause unnatural cracks, which can lead to rocks dislodging, potentially crushing workers.
Drill operators like Ditibane are almost all Black and have historically borne the greatest risks. The miners work in cramped conditions and use hydropower rock drills to drill holes into the rock face. The mine is then cleared for detonation by other miners who insert explosives into the holes. The rubble is then hauled to the surface by miners, who process it to extract gold and platinum. The tunnel’s ceiling has netting installed to prevent rockfall-related injuries. Visual: Ed Stoddard, Undark
During apartheid, which subjected a overwhelmingly Black, migrant labor workforce to ruthless exploitation–miners often had little safety protections. In 1986, 800 South African miners died at work. Since the end of apartheid in 1994, South Africa’s mines have gradually become safer. Fatalities reached a record low of 51 in 2019–still almost one per week on average. During the Covid-19 pandemic, those figures rose again, although to nowhere near their apartheid levels. The leading cause of deaths are FOGs: From 2000 to 2021, rockfalls accounted for 39 percent of mine fatalities, according to Undark’s calculation from industry and government data.
There have been many factors that have contributed to the improvement in safety records. Regulations passed in 1996 forced mines to implement new safety standards, and subjected them to more regular inspections.
Many mining companies have also seen their
Incentives shift. Investors are more concerned with safety and at some companies, compensation for CEOs is tied to safety records. Mines can be shut down for extended periods of time due to accidents. May Hermanus, a former chief inspector of South Africa’s mines, stated that all of these costs are now being considered extremely serious.
Mines install safety netting and bolting on the roof of underground mines to prevent FOGs. The practice was once used only in select cases, but it has been widely adopted over the past decade. The basic idea is that the mesh captures any loose rocks as they fall.
Recently industry groups have acknowledged that more changes are needed. In July 2021, the Minerals Council unveiled an action plan to eliminate FOG fatalities. Its analysis showed “a steep reduction in FOG fatalities between 2003 and 2011, followed by a plateauing period between 2012 and 2020.”
According to Paul Dunne (CEO of Northam Platinum Holdings Limited), there had been a decline in safety. He said that all the CEOs were unhappy about this. Dunne’s company owns three platinum mines in South Africa. He said that the greatest risk was from ground falls. “That’s why .”
was chosen to address it.
Experts are now looking for a more efficient tool to forecast FOGs in advance.
In 2013, a wall gave way at the Bingham Canyon Mine, an open-pit copper mine outside Salt Lake City, Utah. The landslide spewed 165 million tons of rock–enough, according to a team of geologists who analyzed the incident, to cover New York City’s Central Park 65-feet deep in debris. They wrote that the event was “likely to be the largest non-volcanic landlide in North American History .”
But nobody was there. A radar developed by IDS GeoRadar had detected increasing instability before the slide. Francesca Guerra (the marketing manager for the Italian company), wrote an email to Undark, stating that mining operations had been shut down the day before the slide. There were no injuries.
IDS and other companies have been working to bring such technology–which detects movement without entering the rock–underground. IDS claims that the technology has been deployed around the world, and is currently being used in South Africa in “special projects .”
However, moving such radar underground poses challenges. The radar used on the surface is particularly heavy at more than two tons.
In recent times, Anglo American Platinum, a South African technology company, has teamed up with Geobotica to create a handheld underground radar.
” The idea was born from the success in open-pit mines using radar tech.” Riaan Carstens is Anglo’s lead geotechnical engineer. “Wherever it was used effectively, they pretty much eliminated fatalities due to slope failure.” The question was then asked: Can we use this technology underground to warn people living near a possible fall of ground ?”
Geobotica reduced this to a rectangular-shaped device weighing in at 7 ounces.
According to Geobotica CEO Lachie Camp, the device generates an electromagnetic signal that travels through air and bounces off rock surfaces. The radar then picks some of these reflected signals. He explained that the radar sends out a signal that is in a defined wave. If the rock doesn’t move, this angle remains the same. However, if the rock moves slightly, it returns at a slightly different angle.” These slight movements can indicate a possible collapse.
This process is known as interferometry. Power intensity is one of the obstacles to underground adaptations of such technology.
” We create our radar signal digitally using a low-power chip rather than traditional radar components,” Campbell wrote to Undark in an email. He explained that the advances allowed them to shrink a 2.2-ton diesel-powered trailer system to “something that fits in your pocket and runs on a single charge .”
Campbell demonstrated how the radar, which resembles a cellphone, could detect changes when he stops breathing. This is similar to an electrocardiogram. Campbell explained that underground, the radar can filter out movement to focus on the rock and not the people.
“This will allow you to predict if a rock will collapse,” he stated. “You need a precision that is sub-millimeter.”
IDS is also working to reduce the size of a radar for underground use. According to the company, the current model, the HYDRA U, is “designed for quick and easy transportation and deployment in critical area by one person.” It is approximately 4 feet tall when mounted to a tripod and attached to a suitcase-sized power source.
It is not clear if such technology will be widely used. South African mining companies believe such initiatives are worth exploring. However, the price tag could prove problematic. Jared Coetzer from Harmony Gold’s investor relations department said that because of the high costs associated with these advanced technologies, it is necessary to ensure that they are feasible. He manages eight underground mines in South Africa. “We would be open to considering all options to help reduce any incidents .”
The technology has been limited in real-world application underground. It is not certain that it will catch all FOGs. Watson, a rock engineer, stated that radar is not foolproof because geology holds secrets.
” We don’t know yet what kind of movements will take place before there’s a fall of the ground,” he stated. “How much time do you have? Are you able to spend two minutes, one hour or a whole day? .”
is not yet available.
High-tech radar doesn’t obscure the important role that basic tools such as bolting and netting can play in reducing fatalities. Richard Spoor, a South African human rights lawyer, stated that there has been a belief that these falls of the ground can be prevented. “For years, the industry has been skimping on roof support because it is very expensive .”
Four FOG deaths have been reported so far this year according to government figures that were provided to Undark by Allan Seccombe (head communications for the Minerals Council), early last week. That’s far fewer than the 19 on record this time last year.
FOGs may have been responsible for an unknown number of injuries. And South African miners are still being killed on the job in other ways: As of last week, 44 had died in accidents so far in 2022, compared to 55 in the same period last year.
” Our main goal is to ensure there is no harm, zero injuries, and zero deaths in the mining sector,” stated Mammburu of National Union of Mineworkers.
The author of 5 books, 3 of which are New York Times bestsellers. I’ve been published in more than 100 newspapers and magazines and am a frequent commentator on NPR.