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Wednesday 27 March 2013

My visit to Glastonbury

Last week I had the pleasure of visiting Glastonbury, a small town in Somerset best known for its tor and its music festival. Glastonbury Town Council has preemptively declared itself to be 'frack-free'. Much like Frome's similar decision last year, this is more a symbolic gesture, because (a) it's not clear that there is any unconventional gas to be had from around Glastonbury, and (b) if there were, it is unlikely to be developed for many years.

The decision was not a unanimous one. Some councillors felt that the decision had been rushed, having heard only of the negative sides from Frack Free Somerset. Jim Barron, one of the dissenting councilmen, pleaded in the local paper for a more evidence based discussion before any decisions be taken.

As a result, I was asked to come down to Glastonbury one evening after work to give a presentation to the council. You can download the presentation that I ended up giving from here. You might as well read it in full, but here's a potted summary.

I began by explaining what shale gas is, why it is different to conventional gas, and why hydraulic fracturing is necessary. I followed this by explaining the process, including a time-lapse video of a well being drilled and fracked, and an animation showing how microseismic events are used to image where the stimulated fracture is going. I gave a short overview of existing UK onshore oil/gas operations, including the fact that fracking has been done over 200 times in the UK since the 1970s.

I then outlined what I see as the potential issues relating to unconventional gas extraction: water usage, earthquakes, water contamination, air pollution, and surface impacts. The first, water usage, can be quickly shown to be a red herring: the water lost by SouthWest Water through leakage every day would be enough to frack more than 30 wells. I talked about the Blackpool earthquake, discussing how event magnitudes work (and that the event in Blackpool is so small that most of my real-earthquake-studying colleagues wouldn't get out of bed for something 10 times the size), and looking at evidence for fracking-induced earthquakes elsewhere (of which there are a handful in Canada, but none in the US).

Water contamination is perhaps the major issue for fracking. It is clear that there have been some cases of methane contamination through wells, and of chemical spills at the surface. I listed some of the key incidents taken from this report. However, it is important to point out that where methane leakage has occurred, it is inevitably due to shoddy practice from the drillers: poor or incomplete casing and/or missing cement. Equally, it should be fairly easy not to spill chemicals on pads at the surface, while open tailings ponds (often the most common source of surface contamination) are not allowed in the UK. It is most important to consider the context of these incidents: for example, the Groundwater Protection Council estimate that less than 0.1% of wells have seen a problem.   

With respect to air pollution, I showed a number of studies from both Pennsylvania and Texas, which do not show increases in benzene, ozone or volatile organic compounds (VOCs) before and after drilling. I then looked at a study of employee health statistics for the oil and gas industry in comparison to other sectors. If drill pads are unhealthy places to be, with dangerous chemicals being pumped into the air, then surely the employees should be getting the sickest, given that they might be on site 6 days a week for months on end. In fact, sickness rate in the gas industry is pretty consistent with national average rates, and a lot lower than many other industries.

To demonstrate the surface impacts of shale gas extraction, I showed some photos of what the rigs look like during drilling (on site for a month or two), and what the pads look like once the well is completed, and talked about pad spacing (minimum 2 - 6km as an approximation), as well as pointing out other impacts like new pipelines, and the truck journeys to and from the pads.

I then talked about the public debate around fracking in the US, pointing out that it has become highly polarised, with protest groups, but then anti-protest groups who protest the protest groups. I also showed the data from a Pittsburgh public opinion survey that showed that generally fracking does have more support than opposition (although perhaps the opposition is more vociferous).

Finally, as I like to do, I compared the risks from fracking to the risks from conventional gas extraction. To me at least, if you are opposed to fracking, you should be opposed to all hydrocarbon extraction, so I posed the question to Glastonbury's councilmen: take the scary boogey-word 'fracking' out of the question, and ask what would you do if there was a large conventional gas field discovered under Glastonbury. What would you do?


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