JOHANNESBURG (miningweekly.com) – A shift to “regenerative mining” of coal reserves is a crucial part of a solution to a greener, cleaner future, said African Source Markets CEO Bevan Jones on Wednesday.
Jones, a former commodity trader at Macquarie and Rand Merchant Bank, who cofounded the global coal market in London in the late 1990s, spoke to Mining Weekly about the just transition. The opportunity exists to create win-win, sustainable green revenue streams as coal mines approach closure through the simultaneous regeneration of a healthy soil-food web, clean water and air.
The first win will be for surrounding communities facing unemployment and the dangers of ghost towns.
“Obviously, regenerative mining cannot regenerate mined-out coal reserves, but it can work to create healthy soil, water and air,” Jones explained to Mining Weekly.
Coal mining companies steward large tracts of land, and some are already converting water that their operations acidify back into potable water and water that can be used for agriculture.
As Mining Weekly has reported, South Africa has an opportunity to turn the considerable volumes of acid coal mine water into potable water at no cost, with the extraction of valuable potassium nitrate paying for everything and reportedly providing a potential 30% return on investment. This technology converts unwanted ions into fertiliser material for potential agricultural development by near-mine communities, as could have begun as long ago as 1996 at Grootvlei gold mine, on the East Rand, had the Department of Water and Sanitation not opted for a high-cost alternative option that was brought to a halt owing to its unsuitability.
The newly listed Thungela Resources stated in response to Mining Weekly this week that it is aware of the water technology and is investigating its effectiveness. The now Johannesburg- and London-listed Thungela has been unbundled out of Anglo American, which has also been probing the role of mycelium in cleaning up degraded coal land. Jones expressed the hope that Thungela would inherit this research and start to build green businesses on it.
For every environmental problem presented at mine closure, Jones sees a Nature-friendly, symbiotic circular economy solution, that not only creates jobs as part of the just transition, but also regenerates the local environment well beyond the minimum standards of environmental rehabilitation called for by current government regulations.
Nature, helped by composting, phyto mining and silviculture, goes a long way towards reducing costs by herself. Trees and plants absorb carbon dioxide and filter the air, which coal-fired power stations are polluting, whilst deep rooted trees can also suck up acidic mine water and transpire it as fresh water. As Jones pointed out, a network of forests from the lowveld to the highveld could even act as a water pump from the oceans to bring more rain for Mpumalanga farmers.
“Certain types of trees, such as silver birch (despite the fact it’s an alien) and fibre crops such as hemp and bamboo can work exceptionally well in this regard,” he told Mining Weekly.
Moreover, composting acidic soils with local kraal manures, biomass and biochar obtained from cleaning up coal slimes and fines, as well as alkaline fly-ash from Eskom waste dumps, provides another green revenue stream.
“Neighbouring farmers are ready off-takers, and a tonne of decent compost can sell for more than a tonne of coal,” said Jones, who recalled that in 2015, the United Nations Food and Agriculture Organisation calculated that the world had only 60 harvests left (54 now), based on the rate of fertile soil destruction.
Regenerative mining could, he said, help to remedy this problem by regenerating soil to ultimately produce healthier, more nutrient-intensive food.
On the energy front, disused coal mineshafts could, Jones also noted, be used for pumped storage power generation, by releasing water down the shaft during peak load evening hours, and using renewable energy to pump the water back up during the day.
“I therefore see coal mines as a crucial part of the solution to a cleaner future. Create on-mine community centres of artisanal excellence, that run new green-revenue generating businesses, that help to regenerate soil, water and air at the same time. Eventually, grow food too,” said Jones, adding that special note should be taken of agricultural products that do well when grown in the acidic soils that coal mining has left behind.