The latest independent review on shale gas commissioned by the UK Government has reached a positive conclusion, having considered a range of environmental and health & safety issues.
This review, commissioned by the Government’s Chief Scientist, has been carried out by the Royal Society and the Royal Academy of Engineering. It considered the major environmental and health and safety risks associated with hydraulic fracturing, (the technology used to extract shale gas) including geological risks such as seismicity, and environmental risks such as groundwater contamination. It then analysed whether these risks can be effectively managed and if so, how.
Conclusions of review
The key conclusion is that hydraulic fracturing can be managed effectively in the UK, so long as operational best practices are implemented and enforced through regulation.
It recognises that hydraulic fracturing as a means of extracting shale gas is an established technology which has been used in the oil and gas industries for many decades. It also acknowledges that the UK has 60 years’ experience of regulating onshore and offshore oil and gas industries.
The report takes a practical approach, in that it observes that the most likely causes of possible environmental contamination (faulty wells and leaks and spills associated with surface operations) are common to all oil and gas wells and extractive activities. They are not unique to shale gas.
- Ensuring well integrity remains the highest priority
- The risk of contamination of aquifers from fractures is very low provided that shale gas extraction takes place at depths of many hundreds of metres
- Seismicity induced by hydraulic fracturing is likely to be of a smaller magnitude than seismicity related to coal mining activities or natural seismicity, which is low by world standards. Any risk can be reduced by traffic light monitoring systems that use real-time seismic monitoring so that operators can respond quickly
- Open ponds for storing wastewater are not permitted in the UK and there are numerous facilities in the UK for the treatment of similar wastes from the industrial sector
- Disclosure of the constituents of fracturing fluid is already mandatory in the UK, but where possible the use of non-hazardous chemical additives would help to mitigate the impact of any leak or spill
- Well established procedures have been developed for the disposal of naturally occurring radioactive materials (which are present in hydraulic fracturing wastewaters) by the UK's extractive industries.
Various recommendations are made including:
- Co-ordination of the numerous UK bodies with regulatory responsibility for shale gas activities, with a single body to take the lead
- Review of well designs by an independent well examiner from a health and safety and environmental perspective, with onsite inspections
- Well integrity tests to be carried out by the operator as appropriate, such as pressure tests and cement bond logs
- Mandatory Environmental Risk Assessment for all shale gas operations (including seismic activity)
- Robust monitoring of methane and other contaminants in groundwater before, during and after shale gas operations
- Water management in an integrated way to minimise water use and the recycling and reuse of wastewater where possible.
These comments and recommendations are consistent with the attitude of the Environment Agency that shale gas activity can be regulated appropriately, just like any other industrial process, and with the recommendations of previous UK studies. They are also in line with the UK’s general approach to date, that hydraulic fracturing should be allowed to continue with appropriate safeguards and mitigation measures. We now await the publication of DECC’s final report into last year’s seismic events (the consultation period closed at the end of May 2012). In the meantime however, this latest independent review takes a practical and balanced approach, with an emphasis on well integrity and monitoring which augurs well for the future of shale gas in the UK.