Let’s talk about earthquakes and fracking. To be clear, I’m going to try to address this from a scientific approach, to explain potential environmental concerns (and not just say that fracking is causing earthquakes). I recently attended a lecture presented by Cliff Frohlich, an Associate Director and Senior Research Scientist for Jackson School of Geosciences at the University of Texas, Austin. Dr. Frolich gave an engaging lecture on his research related to seismic activity and hydraulic fracturing. Most of the information I’ll bring up came from that lecture.
But to back up a bit, let’s define some important subjects so we’re all on the same page. “Hydraulic Fracturing” (fracking) is the process of injecting a fluid into a non-permeable bedrock formation to fracture the bedrock, allowing the flow of hydrocarbons (1). The technology has been in use since the 1940’s, but its popularity has increased over the last decade. Water is typically used, and may contain salts, acids or other additives to improve the fracturing of bedrock based on its chemical composition. Another important industrial practice to address is injection wells. These wells inject waste water produced during hydrocarbon extraction (2). This may be excess waste water from the fracking injection, or water that contains salts or other contaminants that were present in the hydrocarbon deposit. Injection wells are commonly used with fracking wells, as it is very difficult to process the excess contaminated water. Given the pressurized nature of fracking operations, it is possible that fracking may cause seismic activity! But, it’s important that we figure out which process, if any, is actually responsible for additional seismic activity. Seismic activity is relevant from an environmental perspective, as it has a direct impact on human quality of life, and can disrupt ecosystems. Dr. Frohlich brought up the Barnett Shale formation near Dallas-Fort Worth, Texas. In his research, he found that 10 small earthquakes were experienced within 1 km^2 of an injection well in 2008. This concentration of seismic activity was determined to be the result of the injection well, which meant that fracking related activities were responsible(3). However, it is important to note that these quakes were caused by injection, rather that the act of fracking. Another case that Dr. Frohlich discussed was North Dakota. Fracking practices increased in North Dakota, as they did in Texas, but no noticeable increase in seismic activity. He drew the conclusion that the geological make up of North Dakota is arranged in such a way that shifting pressures will not cause major seismic activity. Here in Alberta, fracking operations have been tied to a recent increase in seismic activities near Fox Creek. Research has found that both fracking and injection wells have caused seismic activity in the region. The geology in the area is affected both by the injection of fracking fluids and waste aqueous solutions. In response to the increases in seismic activity, the Alberta Energy Regulator (AER) created Subsurface Order No. 2(4). All well licensees on the Duvernay Shale performing fracking and related operations have to follow Subsurface Order No. 2. The Duvernay Shale is a formation in Alberta which is currently being explored and developed through fracking, and is deeper than most of the traditional formations being explored in the area(5). Subsurface Order No. 2 requires operators of fracking or related operations to have a monitoring and response procedure in place for induced seismicity within 5 km of operations. Seismic events between 2.0 and 4.0 on the Richter scale detected during fracking or other injection events must be reported immediately to the AER and a site specific “induced seismicity plan”(4) must be enacted. This is put in place to reduce the likelihood of escalating seismic activity in Alberta. In the case of induced seismicity exceeding 4.0, it must immediately be reported, and fracking or injection operations on the site will be suspended, pending approval from the AER. Reviewing these three case studies brings about the conclusion that the geologic make up of an area and the formations being worked with will determine the degree of seismic activity caused by fracking. Since the geologic formations being interacted with are extremely deep underground, it is difficult to predict how they will react to the increases in pressure and available fluids caused by fracking and deep well injection. More research is required before any complete consensus can be made, but as fracking becomes more common, its environmental impacts will become more apparent; the impacts it has on seismic activity may not be apparent in all areas, but fracking and injection has the potential to cause significant seismic activity and subsequent issues. Brett McMillan
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On September 10th, the Energy Club held its Annual General Meeting (AGM), and I attended my first ever event with the organization. It became clear to me when Mr. Richard Dixon began his talk on critical energy issues that you cannot separate energy issues from environmental ones. Expecting that the environmental agenda may not have a huge part in the conversation, I was pleasantly surprised to see that it was deeply steeped in the topic. Mr. Dixon, who works as Chief of Strategic Foresight for the Alberta Energy Regulator (AER) and is an Adjunct Professor for the Alberta School of Business, touched on a lot of different things in his talk - from electric cars, to the current energy crisis, to the new government in Alberta and its bourgeoning relationship with the energy industry. A few things stood out to me in particular.
The Nexen shutdown, brought about by a recent spill and shoddy regulatory compliance at their Long Lake oil sands operation[2], is an especially relevant topic to me as an environmental engineer. Mr. Dixon used the ‘red card’ analogy during his talk[1], comparing the Alberta Energy Regulator (AER) to a referee in a game of soccer. If there’s someone who isn’t playing by the rules, it is the referee’s job to remove them from play and preserve the integrity of the game. In the proverbial game of energy and oil sands development, the same principle applies. The move by the AER to suspend Nexen’s operation pending evidence that they can operate safely and comply with regulation[2] was very powerful. It makes me excited to see that we now seem to be in a place where environmental regulation holds power over the energy sector, and not the other way around. I think it’s indicative of shifting values, even in ultra-conservative Alberta. Energy and environmental stewardship are becoming a package deal. That is a beautiful thing. Beyond the touchy-feely stuff, I think that this system will actually work best for everyone. To bring back the soccer analogy and quote Mr. Dixon again, “referees that do their job well are supported by teams.”[1] The AER is right to not tolerate environmental negligence. Allowing the errors of the past to propagate forward will only serve to slow progress. If we want to ensure that irresponsible pipeline operation is a thing of the past, we have to make sure there’s no room for it in our future. Another thing that was apparent to me about Mr. Dixon himself is his optimism about the future of energy. One of the aspects he is most excited about is the innovation it will bring as we find solutions for the shortcomings of the present and move forwards to new methods of energy provision. And I’ll admit that now, having heard him speak, I’m excited too. The prospect that the next energy revolution could be just around the corner, and may bring with it crazy things like electric cars that run on salt water (I’m not kidding)[3], seems almost too good to be true. And the thought that my peers and I could eventually be working in and around the energy industry, and have a part in bringing that to fruition, is both daunting and exciting. But, looking around the room at the AGM and seeing so many bright people come together to support a better future for energy, I think I could see what Mr. Dixon sees. With collective brainpower like that behind it, it’s anyone’s best guess as to how far this thing could go. Emily Hunter
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