Extracting natural gas from shale formations using hydraulic fracturing (fracking) "has no direct connection" to groundwater contamination reports, based on a study of three big shale gas plays in the United States, the Energy Institute at the University of Texas at Austin (UT) said in a new report.
The report, released Thursday at the annual meeting of the American Association for the Advancement of Science in Vancouver, BC, concluded that many of the problems attributed to fracking actually may be from casing failures or poor cement jobs -- problems that could occur at any gas or oil drilling operation.
Evidence was examined by the UT researchers using reports that attributed fracking to groundwater contamination in three of the country's biggest unconventional gas plays: the Barnett, Marcellus and Haynesville shales. Faculty members from across the UT campus participated in the research, which the Energy Institute funded. The Environmental Defense Fund also assisted in developing the scope of work and methodology for the study.
According to the researchers, many of the reports about contamination could be traced to above-ground spills or by wastewater produced from shale gas drilling that was mishandled, rather than from fracking per se, said Charles "Chip" Groat, an Energy Institute associate director who led the project.
"These problems are not unique to hydraulic fracturing," Groat said.
The report also identifies regulations related to shale gas development and evaluates individual states' capacity to enforce existing regulations. In addition, university researchers analyzed public perceptions of fracking, as derived from popular media, scientific literature and online surveys.
"Our goal was to provide policymakers a foundation for developing sensible regulations that ensure responsible shale gas development," Groat said. "What we've tried to do is separate fact from fiction."
Researchers plan to supplement the study with an examination of reports relating to atmospheric emissions and seismic activity attributed to fracking, which have emerged in recent months as significant issues of concern in some areas where unconventional drilling is taking place.
According to the report:
"Entirely too often, the debate surrounding the responsible development of shale gas is clouded by rhetoric that is unsupported by the facts, proven data and substantiated science," said Marcellus Shale Coalition President Kathryn Z. Klaber. "This new study, however, aims to objectively separate fact from fiction, and does so effectively. Not surprisingly, though disappointingly, the study also captures the negative and one-sided nature of the media coverage surrounding shale gas development."
The Energy Institute has two other studies in the Barnett Shale related to the use of fracking in shale gas development, Groat noted.
The first project, which is to begin in April, will look at claims of groundwater contamination in the Barnett Shale. The research is to examine various aspects of shale gas development, including site preparation, drilling and production, as well as handling and disposal of flowback water. Researchers also plan to identify and document activities unrelated to shale gas development that have resulted in water contamination. In addition, the project is to assess the quantity of fresh groundwater used in shale gas development and evaluate ways to reduce the amount.
A second project, currently under development, would include a field and laboratory investigation of whether hydrological connectivity exists between water in the units above and below the shale unit being fractured as a result of the fracking process. As envisioned, the project calls for UT researchers to conduct field sampling of fracking fluid, flowback water, produced water, and water from aquifers and other geologic units within the Barnett Shale.