WASHINGTON—Fracking can affect drinking water supplies in certain circumstances, the Obama administration said in a long-awaited report issued Tuesday, leaving open the possibility of more widespread impacts that it says can’t be determined with current data.
The report, written by Environmental Protection Agency scientists, includes findings that are more open-ended than those in a draft version last year, when the agency said fracking, or hydraulic fracturing, isn’t having “widespread, systematic impacts on drinking water.”
The final report doesn’t include that phrase because EPA scientists determined they couldn’t back it up without comprehensive data on hydraulic fracturing across the U.S. and because it didn’t “really communicate the findings in the report,” said Thomas Burke,deputy assistant administrator at EPA on a conference call with reporters Tuesday.
The report is one of a number of actions supported by environmentalists that the Obama administration has taken in its final weeks in office, including denying a permit for a stretch of the Dakota Access Pipeline.
In its draft report on fracking, the EPA said the cases of contamination it found “were small compared to the large number of” fracked wells in the nation. The final report says more broadly that the agency has scientific evidence that fracking activities “can impact drinking water resources under some circumstances.” When asked, Mr. Burke did reiterate the report’s earlier findings that the EPA found only a small number of cases of contamination but stressed the lack of data.
“While the number of identified cases of drinking water contamination is small, the scientific evidence is insufficient to support estimates of the frequency of contamination,” Mr. Burke said. “Scientists involved with finalizing the assessment specifically identified this uncertainty in the report.”
The EPA highlighted a few of those circumstances, such as following surface spills of fracking fluids or when a cement casing of a well is poor and allows chemical-laced liquids to move into groundwater.
The report comes nearly a decade after fracking began helping unlock vast reserves of oil and natural gas across the U.S. Since then, environmentalists and local activists in many areas have worried that it could have harmful effects on the surrounding water, while the energy industry and some consumers have welcomed it as tapping into an abundant source of previously untapped fuel at a relatively low cost.
Fracking involves pumping water, chemicals and sand down a well under intense pressure to split open dense rocks and release the oil and gas trapped underground. But fracked wells produce enough wastewater to cover the island of Manhattan under 100 feet of water annually, according to an article by Rob Jackson, an earth sciences professor at Stanford University who has published several papers on the environmental impact of fracking.
Energy industry executives and other supporters of fracking say the industry has developed effective ways of treating and disposing of the wastewater.
Industry leaders criticized the EPA for changing its conclusion shortly before Mr. Obamaleaves office. “It is beyond absurd for the administration to reverse course on its way out the door,” said Erik Milito, upstream director at the American Petroleum Institute, the U.S.’s biggest oil and natural gas trade group.
Environmentalists, however, praised the EPA for excising the more sweeping earlier conclusion that fracking doesn’t have a “systematic” impact on drinking water supplies.
“EPA’s initial draft misled the public about the pollution risks of unconventional oil and gas development,” said Mark Brownstein, vice president for climate and energy at the Environmental Defense Fund. “The revised assessment puts an end to the false narrative of risk-free fracking that has been widely promoted by industry.”
Tuesday’s report, which the EPA has been working on for roughly five years, comes in the twilight of President Barack Obama’s eight years in the White House. President-electDonald Trump, who has expressed support for fracking and is filling a cabinet of fellow supporters of the process, could review it. Mr. Burke emphasized that it is a report issued by scientists, not political appointees.
—Russell Gold contributed to this article.
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