Acid mine drainage
Acid Mine Drainage (AMD) occurs when polluted water decants from mines and flows over pyrite, which is commonly known as “fool’s gold”. When pyrite is exposed to oxygen and water, a reaction takes place between the sulphides in the ore rock, and sulphuric acid is formed. Rivers take on a yellow, rusty colour from the iron oxide in the water, which the mining industry euphemistically calls “yellow boy” or “iron boy”, making it sound innocuous, when in it is one of the most dangerous threats to South Africa’s water resources. In some instances, water takes on a brilliant turquoise colour, indicating high levels of aluminium. This water is very acidic and high in salts, and also contains heavy metals. When AMD is released into the environment, it can pollute both groundwater and surface water. Its effects are devastating as it leaches into aquifers or flows into rivers and streams. It sterilises soils and contaminates food crops, puts fauna and flora at risk, and is dangerous to human health.The problem of AMD is particularly pressing in the context of South Africa’s legacy of derelict and ownerless mines. Some of these are already causing AMD, while many are ticking time-bombs. According to a report by the Council for Geoscience (CGS), by the end of May 2008 there were 5 906 “officially listed” derelict and ownerless mines in South Africa. The CGS classified 1 730 of these mines as “high risk”, estimating they would require approximately R28.5 billion of the total R30 billion then estimated cost of rehabilitation. In August 2015 it was reported that the estimated cost of this rehabilitation was R60 billion.
Acid mine drainage from coal in eMalahleni and gold on the Witwatersrand is such a serious matter that cabinet convened an Inter-Ministerial Committee (IMC) to investigate this threat and compile a report detailing the estimated costs of resolving the issue. This committee includes the Ministers of Water, Environmental Affairs, Mineral Resources, Finance, Science and Technology, and the Minister in the Presidency for National Planning. The severity of the matter was also recognised in the 2012 National Water Resource Strategy, which stated that acid mine drainage and municipal wastewater pollution had “reached unacceptable levels”.
In 2011, the CER and 51 other civil society organisations and individuals addressed letters to the Inter-Ministerial Task Team on Acid Mine Drainage, urging it to take action.
Here are some useful resources on acid mine drainage:
- Feris L and Kotzé L ‘The Regulation of Acid Mine Drainage in South Africa: Law and Governance Perspectives‘ (2014) Potchefstroom Electronic Law Journal Vol 17 No 5
- McCarthy C ‘The impact of acid mine drainage in South Africa‘ (2011) South African Journal of Science 107 (5/6)