The Environmental Protection Agency just released its final report, Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States. The New York Times' headline on the article about the new report declared that EPA says that "fracking can contaminate drinking water." Similarly, the Washington Post ran its article about the report with a headline saying that the EPA had changed its stand on fracking and that the agency now "says it can harm drinking water in 'some circumstances.'" Well, yes. Mistakes can and will be made in the pursuit of any industrial activity. But the new report provides precious little evidence that fracking has actually caused much harm to drinking water supplies in the United States.
As the Post notes, the new EPA report does change the agency's stand with regard to the overall safety of hydraulic fracking to obtain natural gas and oil from its preliminary 2015 report that "did not find evidence that these mechanisms have led to widespread, systemic impacts on drinking water resources." Howls of protest by anti-fracking activists greeted this benign conclusion and they urged the agency to change its findings. Agencies rarely make findings that go against the aims of their constituencies, and so one can be forgiven for suspecting that the new report stresses uncertainties as a way to mollify activists who need to keep the public alarmed about the alleged dangers of fracking.
So delving into the report, what does the EPA find with regard to fracking? First, most of the instances and speculations cited in the EPA report are applicable to all oil and gas wells, not just to wells created by means of fracking. These include harms caused by spills, leaks due to faulty well casings, and inadequate treatment and disposal of fluids and water that flow from wells.
Focusing chiefly on the process of fracking itself—creating cracks by injecting pressurized fluids into shale rocks as a way to release trapped oil and natural gas—the EPA report looks at four pathways by which fracking specifically could contaminate drinking water supplies. Most of the agency's findings are couched in conditional language. They include the possibility that fluids and natural gas could migrate via fracked cracks that might extend directly into drinking water aquifers; because well casings for horizontal drilling might be less able to withstand the high fracking pressures they may be more likely to leak allowing contaminants to migrate; migration might occur when a fracked well "communicates" with a nearby previously drilled well that is not able to withstand the additional pressures from newly released natural gas; and fracked cracks might intersect with natural faults allowing contaminants to migrate into drinking water supplies.
The EPA cites the results of lots of computer models that find that migration of fluids and natural gas by these four pathways is possible. However, given the fact that by some estimates as many as 35,000 fracked oil and gas wells are drilled each year in the United States, it is astonishing how few examples of actual contamination and other harms are identified in the EPA report. Nevertheless, the report limply observes:
The limited amount of available information also hinders our ability to evaluate how frequently drinking water impacts are occurring, the probability that these impacts occur, or to what extent they are tied to specific well construction, operation, and maintenance practices. This also significantly limits our ability to evaluate the aggregate potential for hydraulic fracturing operations to affect drinking water resources or to identify the potential cause of drinking water contamination in areas where hydraulic fracturing occurs. The absence of this information greatly limits the ability to make quantitative statements about the frequency or severity of these impacts.
Given even the limited quantitative findings in the EPA's final report, the agency should have reaffirmed its original more qualitative statement that there is little "evidence that these mechanisms have led to widespread, systemic impacts on drinking water resources." Sadly, the new report appears to be a parting gift to anti-fracking activists from the Obama administration.