The Environmental Protection Agency on Thursday linked hydraulic fracturing with groundwater contamination in Wyoming _ a first-of-its-kind conclusion by the federal agency that could trigger new scrutiny of the practice used to extract oil and natural gas nationwide.
The EPA announced its findings as part of a three-year probe into possible groundwater contamination in Pavillion, Wyo. In a draft report issued today, the agency said it had discovered synthetic chemicals — including glycols and alcohols — associated with gas production and hydraulic fracturing fluids inside deep water wells in the region.
Although the study is limited to a gas field in Wyoming and is only in a draft form, the EPA’s finding could be a game changer for the oil and gas industry, which has insisted that hydraulic fracturing is safe and should be regulated solely by state officials, rather than the federal government.
About a third of the United States’ natural gas production now comes from the hydraulic fracturing process, which involves blasting mixtures of water, sand and chemicals deep underground and at high pressures to break up dense shale rock and unlock trapped hydrocarbons.
Energy analysts say the hydraulic fracturing process is key to recovering a 100-year supply of natural gas from shale formations nationwide, including the Marcellus in New York and Pennsylvania and the Eagle Ford in Texas.
Environmentalists have long warned that the chemicals used in the process could contaminate local drinking water supplies and that natural gas can leach out of poorly designed and secured wells to pollute groundwater.
But until now, EPA officials said they had found no convincing evidence of such contamination. At Congress’ direction, the agency has launched a three-year study of the intersection of hydraulic fracturing and water.
The Wyoming study is sure to stoke calls for stepped-up regulation of fracturing and natural gas drilling. Already, some states are moving to clamp down on the practice. New York regulators are considering new rules for natural gas drilling and the Texas Railroad Commission is writing new mandates to force companies to disclose the chemicals they use in hydraulic fracturing fluids.
The EPA said its draft report would be available for public comment and submitted to an independent scientific review panel.
“We look forward to having these findings in the draft report informed by a transparent and public review process,” said Denver-based EPA regional administrator Jim Martin.
The agency also stressed that the findings are unique to Pavillion, where fracturing has taken place both in and below the drinking water aquifer and very close to drinking water wells — conditions that are not common elsewhere in the U.S. The region has been home to oil and gas drilling since the 1950s, and some of the 169 gas production wells in the area were fractured at points just 1,220 feet below the ground.
By contrast, in South Texas, energy companies are extracting natural gas from the Eagle Ford shale formation at depths ranging from 4,000 to 14,000 feet below the surface.
Texas Railroad Commission Chairman Elizabeth Ames Jones noted that “the geology of Texas is different.”
“Hydraulic fracturing does not go on close to the surface here and it would be impossible to migrate up from miles below the earth to a water table,” she said. Already “stringent rules on well construction” in Texas ensure “there is no reason to apply this EPA finding” in the Lone Star State, Jones added.
Industry representatives and their allies on Capitol Hill blasted the EPA’s report, with Sen. James Inhofe, R-Okla., calling it politically motivated and “premature.”
“It is irresponsible for EPA to release such an explosive announcement without objective peer review,” Inhofe said.
Chris Tucker, a spokesman for the industry group Energy In Depth, said the report was flawed with “a lot of basic things wrong.”
“Unfortunately, in the fun house mirror world of anti-fracturing advocacy, some will attempt to use this as a justification to shut down an entire industry, even if the issues out there have nothing to do with it,” Tucker said.
Wyoming Gov. Matt Mead also questioned the study’s soundness.
“The draft study could have a critical impact on the energy industry and on the country, so it is imperative that we not make conclusions based on only four data points,” Mead said in a statement. “It would not be appropriate to make a judgment without verifying all of the testing that has been done.”
Wyoming regulators have raised questions about some of the samples drawn by EPA’s deep test wells, after some of the results could not be replicated.
“More sampling is needed to rule out surface contamination or the process of building these test wells as the source of the concerning reports,” said Tom Doll, supervisor of Wyoming Oil and Gas Conservation.
But environmentalists said the EPA’s report underscored concerns they have been raising for years, by concluding that poorly constructed and cemented wells, channels in underground rock and other conditions may have allowed chemicals to enter Pavillion’s water supplies.
“We’ve been concerned about the risks for a long time,” said Amy Mall, a senior policy analyst with the Natural Resources Defense Council. “This study shows there are several different things that can go wrong.”
The EPA’s findings also highlight the importance of tough standards and drilling decisions that take local geology into account, Mall said.
“States have been playing catch up when people complained” about possible pollution, she said. For instance, after landowners in Dimock, Pa., and in Pavillion, Wyo., raised concerns, regulators imposed new rules on hydraulic fracturing and natural gas production. But, Mall said, “they’re catching up after something happens. They’re not ahead of the curve.”
Most of the gas wells around Pavillion are owned by Alberta, Canada-based Encana Corp., which has been providing drinking water to 21 families since August 2010. Other residents have been purchasing water on their own because of long-term concerns with water in the region.
Encana spokesman Doug Hock said the EPA’s findings are “inconclusive.” They indicate a “probability” — not a “conclusion,” Hock said.
“For an agency that deals in science, it’s kind of surprising that they would put something out that is really not definitive,” Hock added.
The EPA monitored the region from March 2009 through April 2011. After initially discovering methane and dissolved hydrocarbons in some water samples, the EPA broadened its testing of groundwater from wells in the area and installed its own deep monitoring wells.
Ultimately, the agency discovered high concentrations of benzene, diesel range organics and other chemicals in groundwater samples taken from shallow monitoring wells near 33 surface pits used to hold wastewater and drilling material — indicating that they could be a source of contamination.
Other synthetic compounds associated with hydraulic fracturing fluids also were detected in the groundwater. Those included chemicals tied to components of surfactants, foaming agents, fuel additives and other materials often used as part of the fracturing process, including at least one the EPA said “is not expected to occur naturally in ground water.”
The agency insisted that it considered a range of explanations, but that “the data indicates likely impact to groundwater that can be explained by hydraulic fracturing.”
Other results showing elevated levels of gas in the area’s groundwater, possibly because it had migrated from wells that the EPA said had only “sporadic” barriers or, in some cases, no cement at all over large vertical stretches.
Here is the report: