Is fracking safe? Surface and ground water
Canada has a lot to gain from developing its shale oil and gas resources through the use of hydraulic fracturing, a method of extraction where water, sand (proppant) and a small percentage of chemicals are injected under high pressure into rock formations, causing them to fracture and release oil and gas.
At the end of 2014, we released a study which surveyed studies primarily from government agencies and academies on the risks of hydraulic fracturing, ultimately concluding that while there are indeed risks, as there are with just about any industrial activity, these risks appear to be modest and for the most part manageable under current regulation.
In a recent Fraser Institute study, we provide an update, focusing on literature that had been published subsequent to the previous study, ultimately resulting in similar conclusions.
But hydraulic fracturing has drawn the ire of activists who argue that it’s too dangerous and should be banned. We find these conclusions to be unfounded based on our reading of the broader literature. Over the next couple of weeks we will breakout some of the findings of our latest research, as well as present the results of some recent research that did not make it into our study, for five key areas of safety:
- Risk to surface and ground water
- Well integrity and fracturing induced stress
- Water requirements
- Impacts on air
- Induced seismicity
In this blog post, we will start by assessing the notion that hydraulic fracturing pollutes surface and ground water. This has been one of the most contentious issues in debates over hydraulic fracturing.
Many of the widespread concerns over the risks hydraulic fracturing poses to water should be mitigated by the results of a multi-year analysis recently released by the U.S. Environmental Protection Agency (EPA), not exactly a pro-fossil fuel interest group. The EPA concluded that:
“We did not find evidence that these mechanisms have led to widespread, systemic impacts on drinking water resources in the United States. Of the potential mechanisms identified in this report, we found specific instances where one or more mechanisms led to impacts on drinking water resources, including contamination of drinking water wells. The number of identified cases, however, was small compared to the number of hydraulically fractured wells.” (p. ES-6, emphasis added)
We note that this is currently a draft analysis by the EPA, in the process of external review, and should anything in the analysis change we will update our findings. Nevertheless, the conclusions of the analysis are profound and provide a serious challenge to the narrative that allowing hydraulic fracturing will result in considerable damage to water resources.
The EPA’s result is similar to that of a recent article in the journal Applied Geochemistry. Using 21,044 pre-drilling groundwater samples in the Marcellus and Utica shale formations, the authors concluded that:
“…we see no broad changes in variability of chemical quality in this large dataset to suggest any unusual salinization caused by possible release of produced waters from oil and gas operations, even after thousands of gas wells have been drilled among tens of thousands of domestic wells within the two areas studied.” (p. 54)
These studies complement others which have come to similar conclusions. While there are some instances where hydraulic fracturing fluid has flowed into ground water, the vast majority of hydraulic fracturing takes place without any water contamination.