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.

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No, David Cameron’s speech was not “left wing”

Come on, guys.

There is a strange journalistic phenomenon that occurs when a party leader makes a speech. It is a blend of groupthink, relief, utter certainty, and online backslapping. It happened particularly quickly after David Cameron’s speech to Tory party conference today. A few pundits decided that – because he mentioned, like, diversity and social mobility – this was a centre-left speech. A leftwing speech, even. Or at least a clear grab for the liberal centre ground. And so that’s what everyone now believes. The analysis is decided. The commentary is written. Thank God for that.

Really? It’s quite easy, even as one of those nasty, wicked Tories, to mention that you actually don’t much like racism, and point out that you’d quite like poor children to get jobs, without moving onto Labour's "territory". Which normal person is in favour of discriminating against someone on the basis of race, or blocking opportunity on the basis of class? Of course he’s against that. He’s a politician operating in a liberal democracy. And this isn’t Ukip conference.

Looking at the whole package, it was actually quite a rightwing speech. It was a paean to defence – championing drones, protecting Britain from the evils of the world, and getting all excited about “launching the biggest aircraft carriers in our history”.

It was a festival of flagwaving guff about the British “character”, a celebration of shoehorning our history chronologically onto the curriculum, looking towards a “Greater Britain”, asking for more “national pride”. There was even a Bake Off pun.

He also deployed the illiberal device of inculcating a divide-and-rule fear of the “shadow of extremism – hanging over every single one of us”, informing us that children in UK madrassas are having their “heads filled with poison and their hearts filled with hate”, and saying Britain shouldn’t be “overwhelmed” with refugees, before quickly changing the subject to ousting Assad. How unashamedly centrist, of you, Mr Prime Minister.

Benefit cuts and a reduction of tax credits will mean the Prime Minister’s enthusiasm for “equality of opportunity, as opposed to equality of outcome” will be just that – with the outcome pretty bleak for those who end up losing any opportunity that comes with state support. And his excitement about diversity in his cabinet rings a little hollow the day following a tubthumping anti-immigration speech from his Home Secretary.

If this year's Tory conference wins the party votes, it’ll be because of its conservative commitment – not lefty love bombing.

Anoosh Chakelian is deputy web editor at the New Statesman.