The extraction of shale gas both in the UK and globally is currently one of the hot topics of environmental science. A vigorous debate exists between industrial companies who wish to pursue extraction of methane through a process of hydraulic fracturing (‘fracking’) and environmental groups who are insistent that methane extraction will be detrimental to the environment in numerous ways. This debate is largely fuelled by the persistent coverage of the negative aspects of fracking, as well as perhaps a sense of distrust towards the hydrocarbon industry. However, what is ubiquitous in these debates is a general lack of understanding of the core geoscience and technical aspects of extraction. This information is required, not just for governing bodies and industrial organisations to have an empirical foundation for actions, but also to engender a sense of public confidence through transparency and recognition of a scientifically rigorous basis.
A film called ‘Gasland’ that masquerades itself as a documentary, revolves around methane contamination in local water aquifers in Pennsylvania, USA, as a direct result of fracking processes. The image of the man setting water flowing from his tap on fire is notoriously infamous, and provided the initial fuel for protests and inquiries into extraction activities in the USA. In the UK, a microseismic event correlated with the timing of a pilot drilling operation by Cuadrilla in Lancashire brought fracking to the fore of environmental issues, with vociferous opponents spreading like wildfire. Since the incident, fracking operations have ceased in the UK, although pilot drilling still continues while the final report from DECC is prepared. However, the events surrounding the microseismicity are still unclear. Coupled with fears of water contamination, and issues associated with water usage and disposal, opposition to shale gas extraction is at an all time high. This has somewhat caught industrial and learned organisations unawares, and since the incident, attention has shifted towards acquiring sufficient data to provide a fully-informed assessment of the impacts of shale gas extraction.
The Shale Gas meeting on June 18th held by the Geological Society sought to facilitate the discussion of the latest geoscientific knowledge relating to fracking, targeted at a non-geoscientific audience. The Chair, David Manning, highlighted this in his introduction:
“The talks will focus on the geoscience of shale gas, how geoscience can inform decision making about its extraction and whether this can be done safely. They will not be making judgments on whether it should in fact be extracted.”
The usage of shale gas and effects of associated carbon emissions were also excluded, as these either go beyond the geoscientific scope of the Society, or have existing statements elsewhere. In attendance were members of local councils, water utilities, non-Governmental organisations, and environmental activists.
After providing a background to the actual geology of shale, the talks focussed on the raw empirical evidence behind microseismicity, groundwater contamination, and water usage and waste disposal. For each, the conclusions drawn were quite direct: these are predominantly non-issues, as long as they are managed in a substantial manner, and after additional assessments have been completed. This was capped off by a discussion of the current regulatory framework, and future directions.
Previous issues, such as the methane contamination in the USA, were refuted by strong evidence that induced fractures could never propagate far enough to contaminate aquifers. The source of the methane is as of yet undetermined, but likely candidates seem to have been one of the 187,000 wells that were drilled before records began, any one of which could have been a potential conduit for natural methane seepage (methane is considerably more common as a natural occurrence than typically known). Faulty well casing at old sites is also a potential candidate, but since this discovery, associated drilling companies have been fined for poor practice.
The microseismicity associated with drilling and fracking operations was deduced to be largely insufficient to even be felt by humans. Exceptional events, possibly including that such as the one associated with Cuadrilla, are still relatively insignificant, and likely to have been caused by re-activation of pre-existing faults or weaknesses. This requires further surveying to deduce the real-time effects of fracking based on the antecedent tectonic and stratigraphic structure. In terms of water usage, the amount required for annual fracking activity compared to the water budget in the UK is insignificant. The details regarding the above are predominantly based on the published geoscientific literature (and several articles in press). The talks are to be made public shortly, as are the presentations.
There were several take home messages, in my personal view, from the event:
- The most frequently cited arguments against fracking procedures are mostly non-issues, refuted by peer-reviewed science.
- There are, however, numerous issues yet to be solved, such as how to store and treat fracking fluids, and how to successfully regulate, manage and mitigate all of these.
- Fracking is currently not licensed in the UK. Pilot drilling schemes are, based on previous petroleum licenses, as has been occurring for decades.
- Considerably more data is required. This is in terms of providing baseline geochemical data, to more accurately determine the origin of any extraneous contaminants post-fracking, and providing real-time monitoring of pilot drilling procedures, as well as the seismic tectonostratigraphic structure of prospective shale formations.
- Although a strong regulatory framework exists (much stronger than that for either the USA or Europe), this needs to be scaled to conform to the scale of potential operations, and requires a strong empirical basis to do so.
- It is not just the regulations that matter, but actually managing and enforcing them. Many of the previous issues were ground in poor legislation and relaxed management. Applying more rigour in these aspects should stamp out any potential issues.
- Don’t approach this topic based on what the media tell you, or with a personal agenda. Be objective, and let the science do the talking.
This is by no means a comprehensive list or the final say on shale gas issues in the UK. There is much to be done, in terms of data acquisition, consultation, and public outreach to finalise whether or not extraction should go ahead. If you would like more detailed information on the event, feel free to contact me at the address below.
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Disclaimer: Any views represented in this coverage are strictly personal, and not those of the Geological Society.