Foundation essay: This article on the different international attitudes to fracking by Professor John Paterson, Chair in Law at Aberdeen University, is part of a series marking the launch of The Conversation in the UK. Our foundation essays are longer than our usual comment and analysis articles and take a wider look at key issues affecting society.
Critics of the controversial practice of hydraulic fracturing to extract shale oil and gas - fracking - will not be placated by recently published US draft regulations. Despite extensive consultation by the Bureau of Land Management, the new draft rules have been described as “woefully inadequate” and “an industry wish list” by Frances Beinecke, president of the Natural Resources Defense Council, an environmental lobby group. The Bureau is seeking comments on the latest draft, so the debate is set to continue.
In the UK the debate over fracking restarted after Ed Davey MP, Secretary of State for Energy and Climate Change, indicated to Parliament in December that he was willing to consent to new fracking proposals. Fracking operations had been suspended after exploratory drilling by firm Cuadrilla at sites near Blackpool in 2011 caused seismic tremors. The chances that shale gas developments will move forward in the UK surely increased with the recent news that Centrica have bought into Cuadrilla’s fracking licence.
Elsewhere, however, the debate is already over: a number of countries including Bulgaria and France have banned fracking. For critics, worried about adverse environmental effects, this represents a triumph for common sense over grubby economic and political imperatives. Advocates, worried about energy security, high CO2 emissions from coal-fired power plants, and the efficiency problems of renewables, see the decision to close off the development of shale gas as nothing short of folly.
To understand how the debate around fracking has become so polarised, it is necessary to have greater clarity about what is at stake.
Oil under rock vs oil among the rocks
Conventional oil and gas reservoirs are typically sandstone formations (or some other porous and permeable rock) into which oil and/or gas have naturally migrated (being less dense) from deeper source rocks. Their inexorable rise to the surface has been checked by the presence of an impermeable cap rock (for example, salt) which forms a trap. This is the sort of geological formation oil companies hunt for. When drillers break through the cap rock, the oil and gas are under such pressure in the reservoir rock that they flow naturally to the surface.
In the case of shale oil and gas, the source rock is porous but also impermeable, meaning that the hydrocarbons formed there are unable to migrate upwards and remain trapped. Geologists have known about these potentially rich seams for many years, but until recently the industry has lacked the technology to exploit them.
The development first of hydraulic fracturing and then, crucially, of horizontal drilling means that the technology is now in place. It is the combination of these two techniques, rather than just fracking alone, which has made the commercial exploitation of shale gas possible.
Hydraulic fracturing has been used in the exploitation of conventional oil reservoirs for decades as one means to improve the recovery of hydrocarbons once the natural pressure has begun to drop. The effect of forcing water and sand at high pressure into a well is to fracture the rock and increase its permeability.
With formations such as shales, lacking as they do any (or much) natural permeability, the effect of hydraulic fracturing at the bottom of a conventional well would be limited, as the area affected is relatively restricted. Drill the well horizontally through the shale formation, however, and the area of oil or gas deposit the fracking process affects is greatly increased. This makes it commercially exploitable.
This technique has been so effective in the US that natural gas production has significantly increased, prices have dropped, and manufacturing industry has gained a competitive advantage from the availability of cheap energy. A country that was gearing for substantial imports of liquefied natural gas is now set to become a significant net exporter of gas.
This transformation in the energy fortunes of the US has attracted attention in other countries. Both from policymakers looking for a way out of economic recession and dependency on energy imports, and from environmentalists worried that the inexorable decline of fossil fuels seems to have performed a spectacular reverse. The economic and geopolitical benefits of increased gas production may be clear, but what are the environmental costs?
Wells of discontent
The list of charges levelled against the combination of horizontal drilling and hydraulic fracturing is lengthy and disturbing.
Among the most significant is that, as was famously the case in Britain, fracking can cause earthquakes. It is further claimed that the chemicals contained in the fracking fluid can contaminate groundwater. Chemicals in fracking fluid include gelling agents to carry sand or other “proppants” into the fractures, chelants to break down the gelling agents once they have done their work, and biocides to prevent bacteria contaminating wells. It’s also claimed that fracking can contaminate aquifers with methane, to the extent that tap water can be set alight.
These are among the issues that regulators must address if they are to reassure a nervous public that shale gas can be exploited without damaging the local environment. We can consider how these two key jurisdictions, the US and UK, are dealing with these issues.
It is apparent that while the 10-page UK government statement focuses principally on the steps that will be taken to deal with concerns about seismic tremors, the 170-page document presenting the new draft regulations in the US is entirely silent on this matter. By contrast, the US draft regulations focus on the issue of water contamination, but in the UK statement this is only among a number of other issues raised alongside the principal seismic concern. In other words, it’s possible to read these two documents, which deal with precisely the same technical operation, as driven by the sources of public concern each nation has faced, rather than as a purely technocratic response to the operation.
With regard to the question of fracking fluid chemicals, again a difference in approach between the UK and the US emerges. The UK adopts a straightforward approach that the:
“identity of all substances proposed for injection, and the [regulator’s] conclusions on their hazard potential, will be publicly available”.
The US draft regulations allow operators to submit to the bureau “an affidavit asserting exemption from disclosure of certain information” on the basis that it is protected by trade secrecy law. Providing details to the regulator of which chemicals are being exempted is not an automatic requirement; in fact the draft regulations only give the regulator “the ability to demand the specific chemical details of any materials being proposed for trade secret exemption”.
Finally, in relation to the possibility that fracking could contaminate aquifers with methane, the UK’s approach starts from the observation that there has been no evidence of such contamination. The government’s statement stresses the importance of well integrity, pointing to existing regulations that require the Health and Safety Executive to be notified of well design and operations, and the role of independent verification. In the US, the draft regulations demand proof of well integrity for the entire length of the well and for Cement Evaluation Logging on those sections protecting aquifers.
The rigorous approach to well integrity in both jurisdictions stems from the fact that the industry and environmentalists have similar if differently motivated concerns. The latter are concerned that any compromise to well integrity may result in environmental damage, and the former is concerned that break down of well integrity could see gas escapes which could cause explosions.
Whatever the merits or otherwise of shale gas exploitation, there is also the broader environmental impact to consider. Vast shale gas reserves emit a siren call to those concerned with economic growth and energy security, but the International Energy Agency has recently warned that if greenhouse gas emission reduction targets are to be met then two-thirds of currently proven hydrocarbon reserves cannot be produced without the wide deployment of carbon capture and storage – a technology whose efficacy has not yet been demonstrated.
That would seem to suggest that the story of fracked shale oil and gas could in many places be over before it has begun. But if dirty, polluting coal was replaced by cleaner shale gas to generate electricity - especially in developing countries - CO2 emissions could be halved considerably more easily and cheaply than by any other means. Consider this, and it becomes clear that the decisions facing policymakers – and we as taxpayers and consumers – are by no means as black and white as the polarised debate would lead you to believe.