Thursday, 3 November 2011

Small earthquake in Blackpool: not many dead

In case you'd missed the news, Britain's natural gas reserves have just more than doubled. In a world where people are worried about declining North Sea production and imports of natural gas from Russia, high energy bills, and carbon emissions from all of our coal-burning power stations, you would think that this news would have been greeted with dancing in the streets. But as it is, we're enduring a bout of navel-gazing and a lot of guff being talked by the kind of commentators who wouldn't know a methane molecule if it came out of their backside.

The latest iteration of this story is focusing on the deadly peril to the valuable infrastructure of the Lancashire coast posed by earthquakes. Yes, earthquakes. Fifty of them in all, all caused by some test drilling conducted by UK shale gas pioneers Cuadrilla Resources. At first sight, a worrying development for sure, until you realise that the largest of these "earthquakes" was actually magnitude 2.3 on the Richter scale. For comparison, that's about the same as a car going past you when you're on the pavement, or next door's washing machine entering its spin cycle. It won't rattle your teacup. It certainly won't cause your house to collapse. There are millions of such micro-tremors every year - tens of thousands every day. They are not recorded by any earthquake monitoring body because they are so common and unremarkable. It speaks volumes about a country that is unused to seismic activity in any form, rather than any level of danger. New Zealanders, Californians and Italians, who ignore tremors thousands of times more powerful every single day of the year, are surely laughing up their sleeves at our panicked response.

It is symptomatic, however, of the kind of exaggerated panic that shale gas seems to bring. Shale gas extraction involves pumping an emulsion of 99.9% water and sand into a hole in the ground to cause tiny cracks in gas-bearing rocks, so that the gas de-sorbs and can be collected. Some people also use detergent as a surfactant. Some in the past have used diesel fuel, although this practice is now largely discarded. This happens a kilometre underground, in non-porous rocks. If they weren't non-porous the gas wouldn't have collected there. There are concerns about possible contamination of water tables from leaks as you pump the stuff down. These concerns are valid, but usually overstated. The United States produces half of its natural gas from shale gas, tight gas or coalbed methane, all of which involve some degree of pressure manipulation underground. Of the tens of thousands of wells drilled, there have been two recorded instances of small, localised contamination, caused by shoddy practice. Compare this with the kind of damage that has been done by oil or coal extraction (anyone remember Deepwater Horizon?). Yes, you saw that scene from Gasland on YouTube, where they set light to the water coming from the tap. What the documentary (which makes Michael Moore look like a balanced and nuanced reporter) doesn't tell you is that they could do that long before shale gas drilling came to the area.

I'm not saying that there is no risk, or that there shouldn't be appropriate environmental safeguards in place. Of course there should. Shale gas needs a lot of rigs, which look unsightly for the 18 months or so that they need to be in position. There are some potential concerns about aquifers (although unlike in bits of the US, no British tapwater at all comes from ground aquifers - it all falls from the sky), and surface issues left by careless disposal of waste etc. These can all be regulated. But compare this to open cast coal mines, nuclear power stations, Alberta tar sands, oil spillages from tankers and deep well blowouts, and even the nimbies who don't like the sight of wind turbines (which I happen to think are quite beautiful, but I guess I'm weird). We are talking about enough gas to power the UK for the next 40 or 50 years, and displacing all of that coal, oil and nuclear that we worry so much about. That's surely worth the tiniest bit of risk, isn't it? Isn't it?

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