Fracking: Just what are the risks?

Shale gas: mining the data.

In the early 1990s the oil and gas industry in Texas started to produce gas by drilling into deeply-buried shale layers. They found that creating underground fractures in the layers, later coined ‘fracking’, increased the rates of production and their investments started to make money. This was the start of the shale gas industry in the USA which may now grow in Europe, China and elsewhere around the world.

Hydraulic fracturing is far from being a new technology; it’s been carried out in many wells since the 1940s. But in the last 10 years, its widespread use for recovering gas from shale has led to it becoming extremely controversial.  A tipping point may have been when the filmmaker Josh Fox was asked to lease his land for drilling, it resulted in him making the documentary ‘Gaslands’ (2010), with footage of gas coming out of taps being ignited. The potential link between fracturing and the contamination of water supplies with methane was thus made.  More followed in 2011 when the UK’s first shale gas well was drilled near Blackpool in northwest England and triggered earthquakes up to 2.3 in magnitude. ‘Fracking’ has quickly become a catch-all term for any shale gas operations. 

But what do we actually know about the geological risks? Can fractures created underground really travel much further than we anticipate, intersecting water supplies and polluting them as ‘Gaslands’ suggested? Could the pumping of thousands of cubic metres of water underground cause damaging earthquakes? How much of what we read in the press is scientifically sound?  The debate is polarised with claim and counter claim. 

There is a lot we already know. Hydraulic fractures can form entirely naturally when pressure builds up as rock is buried over millions of years. Underground seams of minerals in fractures have of course been mined for centuries and the processes involved in fracture formation have been well understood since the 1960s.  In the last decade, chimney-like subterranean hydraulic fractures extending vertically for hundreds of metres have been found in many parts of the world. 

‘Unnatural’ or stimulated hydraulic fractures are generated by pumping water and chemical additives into rock layers. The orientation of fractures that grow can be predicted approximately. But it’s a little like smashing a pane of glass: where exactly the cracks occur is different every time. It is difficult to predict whether a fracture will extend beyond the intended geological layer.  Nor is it feasible to calculate whether or not pumping fluid underground to create fractures will cause small earthquakes that could be felt at the surface.

But what we do have is data – and lots of it.  Thousands of fracturing operations have already been completed in the United States and the dimensions of the hydraulic fractures recorded at least for the last ten years. So we can adopt an empirical approach to understanding the chances of a fracture extending further than ever before.  Our analysis shows that the chances of a fracture extending further than 500 metres vertically are very small. There are also hundreds of examples of induced earthquakes caused by activities other than ‘fracking’: the filling of dams, fracturing for geothermal energy, injecting water to maintain oil fields pressure and because of subsidence triggered by mining of oil and gas.

It is claimed that companies involved in shale gas are not releasing data about operations – but in fact there are hundreds of papers in the public domain that can be accessed and I’ve spent months pouring over them while producing a paper on the topic.  The compilation and reviewing of 20 years of shale gas activity will give us a pretty good steer on the chances of something extraordinary happening. It is the sort of data mining task one of our undergraduates would excel in – some studies have been published, but in the surrounding media hysteria, a lot of basic information has been missed. This would go a long way to informing not just the broader public who are often misinformed by the media, but also industry, academic geoscientists and engineers, regulators, non government organisations and publics about safe shale gas operations in a hyperbole-free way.

Richard Davies is Director of Durham Energy Institute.

Fracking vehicles, Getty images.

Richard Davies is Director of Durham Energy Institute.

Photo: Getty
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The rise of the green mayor – Sadiq Khan and the politics of clean energy

At an event at Tate Modern, Sadiq Khan pledged to clean up London's act.

On Thursday night, deep in the bowls of Tate Modern’s turbine hall, London Mayor Sadiq Khan renewed his promise to make the capital a world leader in clean energy and air. Yet his focus was as much on people as power plants – in particular, the need for local authorities to lead where central governments will not.

Khan was there to introduce the screening of a new documentary, From the Ashes, about the demise of the American coal industry. As he noted, Britain continues to battle against the legacy of fossil fuels: “In London today we burn very little coal but we are facing new air pollution challenges brought about for different reasons." 

At a time when the world's leaders are struggling to keep international agreements on climate change afloat, what can mayors do? Khan has pledged to buy only hybrid and zero-emissions buses from next year, and is working towards London becoming a zero carbon city.

Khan has, of course, also gained heroic status for being a bête noire of climate-change-denier-in-chief Donald Trump. On the US president's withdrawal from the Paris Agreement, Khan quipped: “If only he had withdrawn from Twitter.” He had more favourable things to say about the former mayor of New York and climate change activist Michael Bloomberg, who Khan said hailed from “the second greatest city in the world.”

Yet behind his humour was a serious point. Local authorities are having to pick up where both countries' central governments are leaving a void – in improving our air and supporting renewable technology and jobs. Most concerning of all, perhaps, is the way that interest groups representing business are slashing away at the regulations which protect public health, and claiming it as a virtue.

In the UK, documents leaked to Greenpeace’s energy desk show that a government-backed initiative considered proposals for reducing EU rules on fire-safety on the very day of the Grenfell Tower fire. The director of this Red Tape Initiative, Nick Tyrone, told the Guardian that these proposals were rejected. Yet government attempts to water down other EU regulations, such as the energy efficiency directive, still stand.

In America, this blame-game is even more highly charged. Republicans have sworn to replace what they describe as Obama’s “war on coal” with a war on regulation. “I am taking historic steps to lift the restrictions on American energy, to reverse government intrusion, and to cancel job-killing regulations,” Trump announced in March. While he has vowed “to promote clean air and clear water,” he has almost simultaneously signed an order to unravel the Clean Water Rule.

This rhetoric is hurting the very people it claims to protect: miners. From the Ashes shows the many ways that the industry harms wider public health, from water contamination, to air pollution. It also makes a strong case that the American coal industry is in terminal decline, regardless of possibile interventions from government or carbon capture.

Charities like Bloomberg can only do so much to pick up the pieces. The foundation, which helped fund the film, now not only helps support job training programs in coal communities after the Trump administration pulled their funding, but in recent weeks it also promised $15m to UN efforts to tackle climate change – again to help cover Trump's withdrawal from Paris Agreement. “I'm a bit worried about how many cards we're going to have to keep adding to the end of the film”, joked Antha Williams, a Bloomberg representative at the screening, with gallows humour.

Hope also lies with local governments and mayors. The publication of the mayor’s own environment strategy is coming “soon”. Speaking in panel discussion after the film, his deputy mayor for environment and energy, Shirley Rodrigues, described the move to a cleaner future as "an inevitable transition".

Confronting the troubled legacies of our fossil fuel past will not be easy. "We have our own experiences here of our coal mining communities being devastated by the closure of their mines," said Khan. But clean air begins with clean politics; maintaining old ways at the price of health is not one any government must pay. 

'From The Ashes' will premiere on National Geograhpic in the United Kingdom at 9pm on Tuesday, June 27th.

India Bourke is an environment writer and editorial assistant at the New Statesman.

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