ABANDONED MINE A typical extraction at an abandoned and derelict asbestos mine
South Africa is behind the global curve when it comes to the integration of mine closure and rehabilitation in the mining life cycle, with the historical approach of mining companies being to focus predominantly on driving production, states SRK Consulting, a firm of consulting engineers and scientists.
“In terms of implementing mine closure and rehabilitation regulations, the rest of the world has been fairly active in incorporating relevant rehabilitation strategies into its mining plans, compared with South Africa,” adds SRK Consulting principal geochemical scientist James Lake.
“The softer issues like rehabilitation, mine closure and community development have not received the attention they deserve. It is not that we have been doing nothing – we haven’t been doing enough,” he points out.
Many mines in South Africa have closed over the past 20 years, but, to the best of SRK’s knowledge, few, if any, of the associated mining companies have legally been granted closure by government, owing to the Department of Mineral Resources (DMR) being reluctant to issue these certificates, states Lake.
The Department of Environmental Affairs (DEA) and the DMR, which are responsible for monitoring mine closure in South Africa, have realised the need to control the residual impacts of a closed mine and the regulations currently guiding mine closure are being improved through tougher regulations promulgated in November 2015, he stresses, noting that the regulations should facilitate successful mine closure.
“South Africa has a legacy of mines not having been rehabilitated, with 6 000 or more derelict and abandoned mines across the country, and it is government’s responsibility now to ensure that they are adequately rehabilitated. Given the legacy, authorities like the DMR are reluctant to take on any more responsibility in this regard and are, therefore, taking a risk averse approach to issuing closure certificates,” he declares.
SRK is applying a range of integrated specialist skills in assisting the DMR through one of its implementation agents to rehabilitate abandoned and derelict asbestos mine sites around the country.
Because mine closure certificates have not been granted on the closing of mine sites, resulting in the mines retaining legal liability for the operations, which incur expenses to manage, some mining companies have opted to delay the implementation of closure actions. Lake explains that, once a mine has received a closure certificate, it becomes the responsibility of the South African government to monitor the mine to ensure that future damage is minimal.
“When SRK develops a mine closure plan, we identify relinquishment criteria that are unique to each mine. Once a mining company has completed all the relinquishment requirements, it should, theoretically, be ready to receive a closure certificate.”
Lake points out that, once a mine has been successfully closed, there should be no adverse impact on the environment surrounding the operation. Closure strategies would have been engineered to manage the impacts, with the strategy being informed by considering the risk that each facility poses to the environment. For example, measures would have been put in place to reduce the release of contaminated water into the environment, depending on the nature of the ore and the environmental context.