AngloGold offers hope for mining revolution in SA

Miner will begin trial work on a new mining method at its Great Noligwa operation that could unlock millions of ounces sterilised by low grades

ANGLOGOLD Ashanti will begin trial work on a new mining method at its Great Noligwa operation that could unlock millions of ounces sterilised by low grades, reverse the declining gold production trend, and ensure that workers are kept as safe as possible.

AngloGold has pulled together a team from a range of disciplines to find a way to mine gold at increasing depths where safety and costs are prohibitive, thus curtailing the life of mines and contributing to an overall decline in SA’s gold production.

AngloGold has the deepest gold mines in the world, operating at 4km below surface. There are more gold resources up to 5km deep, but new and smarter ways are needed to mine them because of the dangers involved in working at that depth.

Costs at South African gold mines have soared due to double- digit wage increases, electricity price hikes and steadily rising costs of other inputs.

Fatalities on mines, which lead to temporary closures, have become a pressing issue, with union outrage at every death and growing government impatience at the industry’s inability to improve safety. The closures result in lost production and cut into companies’ profits.

AngloGold is forging ahead with technology to switch from conventional, labour-intensive mining to an automated process to extract deep and dangerous-to-reach gold. It will mean fewer people underground, making it politically sensitive for unions and the government, which is anxious about job creation.

The team involved in the studies has kept the unions informed that the work is going ahead. B ut the team will only fully engage the unions once it has a proven technology that is ready to deploy.

"Our concern is where technology is deliberately used to replace workers," National Union of Mineworkers general secretary Frans Baleni said. "We need to engage with AngloGold to look at the pros and cons of what they are proposing and see how it affects workers."

He said the union was aware serious safety challenges had to be addressed as mines go ever deeper and it wanted to participate in methods to ensure workers’ safety, so it was not averse to the introduction of new technology.

Models show the new system should radically change rock stresses and reduce ground-fall incidents, a major killer underground.

It could also reduce by a factor of 10 the number of people needed to work underground.

The Department of Mineral Resources urged AngloGold to balance production, safety and jobs. "We’ll engage with AngloGold to understand the proposal once they have something to show us. We are mindful that advances in technology sometimes encroach on jobs and we as a government want to retain jobs," spokesman Bheki Khumalo said.

AngloGold will encourage offshore suppliers of the equipment needed in the new mining method to build the machinery in SA to offset the reduced worker numbers . "You could say with automation there could potentially be quite significant job losses," said Robbie Lazare, AngloGold’s executive vice-president.

"On the other hand, you could say that from the improved revenue stream for the country and companies, taxes, royalties, other mining areas you could open up and manufacturing capability of this equipment in SA, it provides an upside potential that is huge in the long term compared with the downside in terms of some of the socioeconomic negatives .

"We have to be extremely sensitive in managing the transition from conventional mining to automation without having a negative socioeconomic impact," he said. "In the next 12 months we will start getting the unions more and more involved. We will need a totally different skills set on the mines."

AngloGold has a total endowment of 230-million ounces of gold in SA, going down to 1g/ton in situ. Current mining methods can extract 30-million ; the new method will unlock substantially more .

AngloGold plans to begin trial work on using boring machines to develop tunnels up to and into the C-Reef at Great Noligwa. It will then use smaller borers to extract just gold-bearing reef, reducing the amount of dilution resulting from the need to create working places in stopes big enough to accommodate people.

Using borers will result in a continuous stream of ore , rather than the batches coming from the current system of drilling, blasting, which entails clearing the mine of people, and then cleaning up and removing the rock to the surface.

"It’s the end of drilling and blasting," said Michael Macfarlane, AngloGold’s senior vice-president, technical. "The argument could be made, on paper anyway, that if and when we’re successful with this that we are going to reverse the declining gold production trend."

seccombea@bdfm.co.za