Risks of Shale Gas exploitation in Europe
3. Main causes of risks, impact and mitigation means identified by this study
Three main causes of risks and impacts from high-volume hydraulic fracturing identified were mainly related to the following challenges :
- The use of more significant volumes of water and chemicals and the lower yield of unconventional gas wells compared to conventional gas extraction;
- Ensuring the integrity of wells and other equipment throughout and after the lifetime of the plant;
- The potential toxicity of chemical additives and the challenge to develop greener alternatives; ensuring that spillages of chemicals and waste waters with potential environmental consequences are avoided ;
- Ensuring a correct identification and selection of geological sites;
- The potential uncertainties associated with the long-term presence of hydraulic fracturing fluid in the underground;
- The unavoidable traffic impacts that cannot be entirely avoided;
- The potential for development over a wider area than is typical of conventional gas fields;
- The unavoidable emissions to air and noise impacts related to plant and equipment during well construction and use.
Measures for mitigation of these risks were identified from existing and proposed legislation in the US and Canada where shale gas extraction is currently carried out. A number of the recommendations made by the US Department of Energy are relevant for regulatory authorities in Europe. In particular, it is recommended that the European Commission should take a strategic overview of potential risks.