Frack from fiction

Cuadrilla Resources, the UK firm which caused the incident in July, was last month given permission from the government to resume hydraulic fracturing (or fracking as it’s more commonly known) after it suspended operations. The news did little to dampen concerns about the process, which has triggered waves of fierce debate.

So much so, that Hollywood has decided to tell the story. A new film, Promised Land, which was released in the US this month, takes on the emotive issues surrounding the risks of shale gas extraction. So far, however, scientific debate seems to have taken a backseat to highly emotive statements that have caused so much noise in public and political spheres. But how much of this is hot air?

The process of hydraulic fracturing involves drilling at depths of 1000-4000m into dense shale rock that contains natural gas. A mixture of water, sand and chemicals is blasted in high pressures, opening up fissures in the rock through which gas can escape.

Usually, steel pipe, known as surface casing, is cemented into the uppermost portion of the well to protect the groundwater. Some of the fluid returns to the surface as flowback water.

The controversy surrounding the process focuses on three main points; that methane could escape into the atmosphere and cause global warming; it could contaminate water supplies; and it could set off earthquakes far more serious than the ones felt in Lancashire.

The 2010 Gasland documentary, which explores America’s shale gas industry, is often used by the anti-fracking lobby to highlight concerns over water supply contamination.

At one point during the film, an old man reels back from an explosion after he places a match under his water tap. The film claims extraction of shale gas polluted underground sources of drinking water with methane.

Results of a US Environmental Protection Agency investigation found that water supplies in the town of Pavillion, Wyoming, which has hundreds of gas wells, contained methane gas that matched that occurring at the depths being drilled.

However, a joint report by the Royal Academy of Engineering and the Royal Society claims that while this is a concern, the risk is very low provided that shale gas extraction takes place at depths of many hundreds of metres.

Similarly polarised views are found on the issue of global warming. Natural gas is a relatively cleaner alternative to coal-fired generation and the UK government sees its potential to bridge the gap to cleaner renewables or more nuclear generation.

But experts such as Prof Kevin Anderson, director of the Tyndall Centre for Climate Change Research, believe the shale gas extraction diverts investment from more long-term renewables solutions. According to Anderson,”from a climate-change perspective this stuff simply has to stay in the ground.”\

The lower CO2 emissions of gas compared to coal or oil are countered by methane releases of up to 10% of production. These so-called fugitive emissions mean that shale gas has higher greenhouse gas emissions than conventional gas. The levels of these emissions are significant as methane, over a 100 year timeframe, contributes to climate change at a level 25 times greater than carbon dioxide.

Meanwhile seismic activity continues to be a key concern for the public. But according to the Royal Academy of Engineering, the seismicity induced by hydraulic fracturing is likely to be smaller in magnitude than the UK’s natural earthquakes, as well as those related to coal mining.

“Fracking is well established in the subsurface industry, and monitoring should greatly reduce the risk of earth tremor,” said Edinburgh University’s Prof Stuart Haszeldine. “High quality well casing and sealing of drilling fluids and gas production from surrounding aquifers is equally important, as is control of fugitive emissions. However, I expect the rollout of shale gas in the UK to be a lot slower than the Treasury hope for, and not to control the price of domestic gas supplies.”

The industry itself whole-heartedly denies that shale gas is dangerous and claims evidence if pollution has been the result of bad practice in the industry. Andy Furlong, director of policy at the Institution of Chemical Engineers, believes the UK has the expertise to mitigate these risks.

“Fracking is an established technology that has been used in the oil and gas sector for decades,” he said. “Chemical and process engineers have extensive knowledge of the exploration and production of natural gas. Furthermore, the UK has 60 years’ experience of regulating the oil and gas industries, offshore and onshore.”

Energy secretary, Ed Davey, attempted to allay fears by announcing new industry controls last month. The measures mean that process companies must now conduct a risk review before fracking takes place and submit this to the Department for Energy and Climate Change (DECC) showing how seismic risks will be addressed.

A new traffic light system has been put in place to categorise seismic activity and direct appropriate responses, with a trigger mechanism to stop fracking operations in certain conditions.

Each stage of the process must be designed to use the minimum amount of fracking fluid necessary and well inspections will be mandatory. Companies will also have to make information on the chemicals they use in the process public.

The move was triggered by the growing distrust in the US over the secrecy of chemicals used by some organisations. A study has also been commissioned by DECC into the possible impact of shale gas development on greenhouse gas emissions.

For the shale gas industry, many of the processes and associated risks are shared by other hydrocarbons operations which are robustly regulated in the UK. While horror stories may abound in the US about how fracking has damaged communities, the UK is in a strong position to learn lessons from this and develop carefully regulated and managed exploratory operations.

The government hopes that countering fears with informed scientific debate could help win over the hearts and minds of the public.

The bigger issue is will it be worth it? The most significant unknown is how much shale gas there is in the UK. Many shale-gas enthusiasts claim that there are huge amounts of gas under the ground waiting to be exploited, but this has never been proven. According to the recent parliamentary report ‘Shale gas and fracking’, the industry is unlikely to be a game-changer in the UK to the same extent as in the US due to restricted resources, notably land area.

As well as this, the British Geological Society has estimated that perhaps only 10-20% of the full UK reserve may be recoverable.

Far more exploration needs to take place before any definite conclusions can be drawn on the future of shale gas in the UK. With high-standards of industry regulation, political backing and some luck, shale gas could provide the UK with much-needed energy security.

Uniting process companies and environmentalists on the cause, however, will be a much tougher challenge.