To frack or not to frack?

At the outset of this blog, I declared my agnosticism regarding fracking. The idea of energy independence and economic good times are seductive, especially with my country slowly drifting into the Atlantic following its departure from the European Union. On the other hand, anthropogenic climate change. But on the other hand, domestic gas production might get us off of coal. But on the other hand, the possibility of environmental damage from badly regulated fracking. But… I’ve run out of hands. So how do I feel on the matter now?

Total nihilism. I’ve seen scientific literature, popular publications and some less popular ones, falling vehemently on either side of the debate.  A few voices did a fair job of casting things in a more neutral tone, but it’s virtually impossible not to be deeply cynicised (if that wasn’t previously a word, I feel like it needs to be) by the whole debate.

Even if we imagine that fracking is entirely without risk, with a rigorous, evidence based regulatory underpinning, there is still the issue that we’re using a fossil fuel. I don’t put much stock in the notion that it’s “less evil” than the alternative. The alternative ought to be renewables, but for whatever reason there just doesn’t seem to be a political will to pursue that avenue. I would previously have assumed that it was a response to the “not in my back yard” banners which are aggressively thrust forth when someone even looks like they might be thinking about wind farms, but the same thing is happening with fracking, and politicians are doing everything they can to get the drills going, shy of winding the cranks themselves.

What’s the best outcome given the current trajectory? Assuming fracking does go ahead, I sincerely hope that the optimists are proven correct. I hope that no ecological disasters ensue, requiring cunning politicking to explain as being the actions of “one rogue company”, and that I never again have to hear that ghastly political refrain that “lessons were learned”. Most of the associated risks which I’ve encountered, such as groundwater contamination or earthquakes, can be mitigated if adequate care is taken (especially if the drilling companies hire good Geologists, not that I have a vested interest or anything), so perhaps everything will turn out for the best. It generally does, doesn’t it? I mean, it does sometimes, doesn’t it?

But who regulates the regulators?

The US has a long history of hydraulic fracturing, with the technique applied in some form since the 1940s. With technical advancements, hydraulic fracturing now accounts for more than two thirds of gas production in the US, and over half of oil production, a rapid increase from fairly negligible proportions in 2000. Estimates place the number of hydraulic fracturing operations to date in the region of 300,000 (as of 2015), which should go some way to explaining why I so frequently look to the US for examples in my posts. It’s therefore important to consider how applicable these studies are to hydraulic fracturing in other countries, particularly the UK. The big difference is regulation.

Federal regulations are applicable across every state in the US, with individual states having their own additional regulations. A pattern with hydraulic fracturing regulation seems to be that federal regulations tend to leave the specifics in many areas at the discretion of individual states. For example the federal Safe Drinking Water Act (1974) was enacted to avoid contamination of surface or underground sources of drinking water, with specific requirements for the monitoring and reporting of “State Underground Injection Control Programs”. However a 2005 amendment specifically excludes “the underground injection of fluids or propping agents (other than diesel fuels) pursuant to hydraulic fracturing operations related to oil, gas, or geothermal production activities.” This leaves the level of oversight to be defined by state legislation.

Many variances exist between state legislations. Colorado, Ohio and Pennsylvania enforce regulations pertaining to pollutant monitoring in surrounding water, well casing designs and stimulation procedures, whereas Texas and Michigan rely on enforcement of pre existing technical regulations to oversee these areas.

The resultant mosaic of regulation means that the degree of scrutiny given to any particular operation depends largely on which state it takes place in. Also by effectively being the forerunners of hydraulic fracturing, the US has often had to respond to reports of environmental damage with new legislation. It’s worth considering then if the UK has a regulatory framework which takes the experiences of the US into consideration, especially given a higher population density and a consequently increased risk of harm resulting from environmental damage.

The UK is not without its variances, with devolved governments of the constituent countries taking differing views on fracking. Scotland imposed a moratorium on fracking in January of 2015, with a (non-binding) vote to ban fracking being passed in May of 2016. The Welsh government has taken similar measures, issuing a Direction preventing the approval of fracking by local authorities, with the Welsh Labour Party further announcing their intention in September 2016 to ban fracking. This follows a UK wide moratorium called in 2011 following the seismic events at the Preese Hall 1 exploration well near Blackpool, which was subsequently lifted in 2012. It should be noted that prior to the seismic events at Preese Hall 1, there was no regulatory consideration for seismicity. This doesn’t bode particularly well for the notion that the UK can avoid mistakes by considering the experiences of the US.

While legislation regarding fracking is in something of a state of flux, with a new briefing paper released less than a week ago, many of the regulatory frameworks applied to fracking are inherited from conventional hydrocarbon extraction, and make few specific considerations for unconventional hydrocarbon extraction.

The risk of this approach is that new regulation will only follow instances where the current regulation proves to be inadequate to prevent environmental damage. With the government strongly pushing the case for fracking, it’s not hard to imagine a desire not to “over regulate”, but with the corresponding opposition to fracking across the general public they will have to tread a very fine line.

Shaking All Over - Hydraulic Fracturing and Earthquakes

The Earth’s crust is a dynamic affair, with tectonic plates ever shifting, converging, diverging and rubbing against one another. As two plates interact, seismic pressure is stored and released in the adjacent rock. The release of this pressure is manifested in earthquakes, with the size depending on the amount of pressure, and how well the intervening layers of rock absorb or conduct the vibrations. It’s not just the adjacent rock which gets in on the act, as tectonic plates can converge, causing “crumpling”, or diverge and leave tension in rocks far from the tectonic fault itself. To complicate matters further, the rock can quite happily remain under pressure for an extended period, until a change in equilibrium causes the pressure to be released. So, does injecting large quantities of water into the ground facilitate the release of stored seismic pressure? Undoubtedly yes, but the hydraulic fracturing process is not the biggest offender here.

The path of fluid from an injection site to
an adjacent fault. Image: Davies et al. 2013

It’s worth noting that disposal of flowback water is not permitted in the UK or anywhere in Europe, so concerns about seismicity should be focused on the events which can result from the hydraulic fracturing process itself. As it stands, the magnitude of earthquakes resulting from hydraulic fracturing are not adequate to cause much in the way of property damage, but a deep understanding of the surrounding geology is critical to ensure that it stays this way.

Induced earthquakes (those which are caused by human activity) result from changes in the loading state of the Earth’s crust such as the removal of material during mining, or extraction of large quantities of oil or gas. Due to the “tight” formations which are generally targeted during hydraulic fracturing operations, this is not considered to be a high risk, as the tight rocks (shale, for example) are dense enough to maintain structural integrity. Faults (interfaces between separate rock faces) can be “activated” by environmental changes, such as reduced friction from increased fluid pressure, resulting in and stored pressure being released as the rock elements slide against each other.

The quantity and duration of water injection are significant risk factors for induced seismicity, and wastewater disposal wells tend to beat fracking on all of these fronts. They’re also utilised in various forms of mining, even in the absence of hydraulic fracturing. That’s not to say that hydraulic fracturing doesn’t have an associated risk. The Preese Hall 1 exploration well near to Blackpool in the UK experienced two earthquakes, of magnitude 2.3 and 1.5, chronologically congruent with water injection. It was concluded that an inactive fault was reactivated by the increased water pressure, but that the fault in question was perhaps unusually susceptible to this sort of event due to its steep angle.

Coming up:

• UK policy in contrast to the US