Hydraulic Fracturing — a South African Perspective

The promise of natural gas to be a “game-changer” in energy-related questions has stimulated interest in central South Africa (a region which is generally known as the Karoo) fossil resources and political leadership is engaging in shale gas development. The moratorium issued on application requests by energy firms to explore economical viable gas reserves was lifted in September 2012 and public debate is gaining momentum concerning the effects of hydraulic fracturing.

Hydraulic fracturing has become a prevalent public and regulatory issue in most countries developing shale gas. One of the key issues being debated is the protection of groundwater resources in rural areas, since most of South Africa’s rural and some inland cities are dependent on groundwater for potable water supply. Much interest in the country is now directed towards the Karoo because of its potential to deliver shale gas as a future fuel source. Production of shale gas by means of hydraulic fracturing has the potential of contaminating shallow groundwater resources. A large range of chemical elements that could pollute the freshwater is possible, e.g. (a) the current groundwater and methane that is captured in the organic Ecca shale, (b) fracking fluids that will be used during the process, and (c) existing elements in the shale that will be released due to input of fracking fluids, e.g., NORMs. Water currently captured in the organic shale is not suitable for drinking by humans. Due to the unique geological structure of the Karoo, the presence of dolerite structures, a number of risk mitigation methods might be required to successfully develop hydraulically fractured wells. Holistically, the chemical and hydrogeological impacts related to wellfield development cannot be ignored in the Karoo aquifer system, as it has the potential to directly influence human and environmental health.