"While mines today are very aware of their legal responsibilities regarding their immediate environment, natural processes are obviously not confined to individual parcels of land," said Ingrid Watson of the CSMI at the Wits School of Mining Engineering. "The impact of mining and mine closure are felt way beyond these artificial boundaries.
"There is a broader landscape where ecological processes have been disrupted as a result of mining and associated activities, such as expanding settlement and infrastructure. These are the induced and cumulative impacts of mining that affect the integrity of the environment and its resilience."
To explore these impacts more carefully, Watson is embarking on a case study of the Free State gold fields, where the first shaft was sunk in the 1940s and where over 30 shafts have been sunk since.
"There was really very little development there before the 1940s, after which the town of Welkom sprang up as gold mining transformed the region," she said. "But in 10 to 15 years from now, there will be minimal, if any, gold mining in the Welkom area, so we need to start looking ahead and planning for this eventuality."
This gold boom around Welkom presents a useful example of the cumulative impact of mining, as it has taken place in a relatively short period of time during which the geography of the area has been visually documented - allowing comparisons to be made of the era before, during and after mining.
The research will include the examination of aerial photographs and satellite images of the Free State gold fields region, tracking how the landscape has changed around the mines themselves and the settlements in the area. The results will be analysed in terms of policy and socio-economic trends over time, and augmented with interviews.
"While much of our early data will come from aerial photographs, there is now the technology to detect environmental impacts and change, such as underground water pollution, from satellite images," she said. "This allows the tracing of pollution plumes downstream of slimes and tailings facilities, for instance."
The key theme is that environmental processes function over a landscape rather than just on individual parcels of land, pointing to the value of taking a regional approach to evaluating environmental impacts for purposes of mine licensing and closure.
Watson noted the government's reticence in issuing closure certificates to mines in the light of potentially large environmental liabilities - many of which would show themselves only many years after mining has ceased; she contended that a regional approach helps address liability issues by sharing in the solution.
"If there was greater collaboration between mining companies, they could be more successful at creating functional ecosystems," she said. "Your mine's water doesn't just stop at the boundary, so how are you and your neighbour going to manage this issue?"
A good example of inter-company cooperation is the Emalahleni water reclamation plant in the Witbank coalfields of Mpumalanga. A public-private partnership between Anglo Thermal Coal, BHP Billiton Energy Coal South Africa and the Emalahleni Local Municipality, the plant purifies 25 megalitres of water per day from underground coal mine workings.
Once potable, most of this water is pumped directly into the municipality's reservoirs, meeting some 20% of its daily water requirements. This prevents polluted mine water from decanting into the environment and the local river system, while also alleviating serious operational and safety challenges for the mines themselves.
"While these mining groups compete in every other respect, the environment is one area which is non-competitive, and in which all players can benefit from working beyond the confines of their mining leases," said Watson.
This becomes even more relevant in the light of the Department of Mineral Resources' draft amendments to the Mineral and Petroleum Resources Development Act, which would make it even more difficult for mine owners to be released from their environmental liability.
The amendment proposes that an owner remains responsible for any pollution caused, notwithstanding the issuing of a closure certificate; it also proposes that a previous owner must keep a financial provision for environmental impacts for 20 years after a closure certificate is issued.
"If industry and government can start to appreciate the impact of mining on the regional landscape, then we can find policies and practices that will more effectively prevent and mitigate environmental damage," she said. "This means understanding what 'services' the environment offers - water, filtration, soil formation, energy sources, etc - and how mining affects these services."
When a mine closes, for instance, the community that is left behind often becomes much more dependent on these services, such as clean water or agricultural land, she said. These resources, however, might not be available due to degradation by mining activity.
She believes that the CSMI research will chart new ways for the mining industry to address its environmental impact, building on the need to nurture a resilient ecological infrastructure based on bio-diversity across the landscape and not just on one mine property.
