The UK Government’s Chief Scientific Adviser, Sir John Beddington FRS, asked the Royal Society and the Royal Academy of Engineering to review the scientific and engineering evidence and consider whether the risks associated with hydraulic fracturing (often termed ‘fracking’) as a means to extract shale gas could be managed effectively in the UK.
The key findings of this review were:
- The health, safety and environmental risks can be managed effectively in the UK. Operational best practices must be implemented and enforced through strong regulation.
- Fracture propagation is an unlikely cause of contamination. The risk of fractures propagating to reach overlying aquifers is very low provided that shale gas extraction takes place at depths of many hundreds of metres or several kilometres. Even if fractures reached overlying aquifers, the necessary pressure conditions for contaminants to flow are very unlikely to be met given the UK’s shale gas hydrogeological environments.
- Well integrity is the highest priority. More likely causes of possible contamination include faulty wells. The UK’s unique well examination scheme was set up so that independent, specialist experts could review the design of every offshore well. This scheme must be made fit for purpose for onshore activities.
- Robust monitoring is vital. Monitoring should be carried out before, during and after shale gas operations to detect methane and other contaminants in groundwater and potential leakages of methane and other gases into the atmosphere.
- An Environmental Risk Assessment (ERA) should be mandatory. Every shale gas operation should assess risks across the entire lifecycle of operations, from water use through to the disposal of wastes and the abandonment of wells.
- Seismic risks are low. Seismicity should be included in the ERA.Seismicity induced by hydraulic fracturing is likely to be of smaller magnitude than the UK’s largest natural seismic events and those induced by coal mining.
- Water requirements can be managed sustainably. Water use is already regulated by the Environment Agency. Integrated operational practices, such as recycling and reusing wastewaters where possible, would help to minimise water requirements further. Options for disposing of wastes should be planned from the outset. Should any onshore disposal wells be necessary in the UK, their construction, regulation and siting would need further consideration.
- Regulation must be fit for purpose. Attention must be paid to the way in which risks scale up should a future shale gas industry develop nationwide. Regulatory co-ordination and capacity must be maintained.
- Policymaking would benefit from further research. The carbon footprint of shale gas extraction needs further research. Further benefit would also be derived from research into the public acceptability of shale gas extraction and use in the context of the UK’s energy, climate and economic policies.