The Facts on Fracking
Some of the local effects of drilling and fracking have gotten a lot of press but caused
few problems, while others are more serious. For example, of the tens of thousands of
deep injection wells in use by the energy industry across the United States, only about
eight locations have experienced injection-induced earthquakes, most too weak to feel
and none causing significant damage.
The Pennsylvania experience with water contamination is also instructive. In Pennsylvania, shale gas is accessed at depths of thousands of feet while drinking water is extracted from depths of only hundreds of feet. Nowhere in the state have fracking compounds injected at depth been shown to contaminate drinking water.
In one study of 200 private water wells in the fracking regions of Pennsylvania, water
quality was the same before and soon after drilling in all wells except one. The only surprise from that study was that many of the wells failed drinking water regulations before drilling started. But trucking and storage accidents have spilled fracking fluids and
brines, leading to contamination of water and soils that had to be cleaned up. The fact
that gas companies do not always disclose the composition of all fracking and drilling
compounds makes it difficult to monitor for injected chemicals in streams and groundwater.
Pennsylvania has also seen instances of methane leaking into aquifers in regions where
shale-gas drilling is ongoing. Some of this gas is “drift gas” that forms naturally in deposits
left behind by the last glaciation. But sometimes methane leaks out of gas wells
because, in 1 to 2 percent of the wells, casings are not structurally sound. The casings
can be fixed to address these minor leaks, and the risk of such methane leaks could further
decrease if casings were designed specifically for each geological location.
The disposal of shale gas brine was initially addressed in Pennsylvania by allowing the
industry to use municipal water treatment plants that were not equipped to handle the
unhealthy components. Since new regulations in 2011, however, Pennsylvania companies
now recycle 90 percent of this briny water by using it to frack more shale.
In sum, the experience of fracking in Pennsylvania has led to industry practices that mitigate the effect of drilling and fracking on the local environment.
And while the natural gas produced by fracking does add greenhouse gases to the atmosphere through leakage during gas extraction and carbon dioxide release during
burning, it in fact holds a significant environmental advantage over coal mining. Shale
gas emits half the carbon dioxide per unit of energy as does coal, and coal burning also
emits metals such as mercury into the atmosphere that eventually settle back into our
soils and waters.
Europe is currently increasing its reliance on coal while discouraging or banning fracking.
If we are going to get our energy from hydrocarbons, blocking fracking while relying
on coal looks like a bad trade-off for the environment.
So, should the United States and Europe encourage fracking or ban it? Short-run economic interests support fracking. In the experience of Pennsylvania, natural gas prices fall and jobs are created both directly in the gas industry and indirectly as regional and national economies benefit from lower energy costs.
Europe can benefit from lessons learned in Pennsylvania, minimizing damage to the local environment. The geopolitical shift that would result from decreasing reliance on oil, and more specifically on Russian oil and gas, is one that European politicians might not want to ignore.
And if natural gas displaces coal, then fracking is good not only for the economy but
also for the global environment.
But if fracked gas merely displaces efforts to develop cleaner, non-carbon, energy
sources without decreasing reliance on coal, the doom and gloom of more rapid global
climate change will be realized.
Susan Brantley is distinguished professor of geosciences and director of the Earth and Environmental
Systems Institute at Pennsylvania State University, and a member of the U.S. National
Academy of Sciences. Anna Meyendorff is a faculty associate at the International Policy Center
of the Ford School of Public Policy at the University of Michigan, and a manager at Analysis
The views expressed in this piece are those of the authors and do not reflect the views of Pennsylvania
State University, the University of Michigan, or Analysis Group.