Here at Weil’s Product Liability Monitor, we keep a close eye on scientific developments related to hydraulic fracturing, or “fracking.”  It’s an exciting topic to follow given the number of ongoing studies on a host of issues–from seismicity and earthquakes, to air and groundwater contamination, to traffic accidents near drilling sites.  Despite the number of eyes on fracking, however, the science still remains quite fluid, with new studies being reported on an almost monthly–if not weekly–basis.  In this post, I provide a brief recap of just a few studies that were published in recent days.

First up, two academic studies examining health and groundwater issues–one out of Yale University and the other from Penn State University.  The study from Yale is titled “Proximity to Natural Gas Wells and Reported Health Status: Results of a Household Survey in Washington County, Pennsylvania” and was published in the National Institutes of Health’s Environmental Health Perspectives (available here).  In the study, researchers analyzed the results of a health symptom survey given to 492 people in 180 randomly selected households with ground-fed wells in an area of active natural gas drilling of the Marcellus formation (Washington County in southwestern Pennsylvania). The researchers compared gas well proximity for each household (households <1 km from a gas well versus those 1-2 km from a gas well, and those >2 km from a gas well) to the prevalence and frequency of reported dermal, respiratory, gastrointestinal, cardiovascular, and neurological symptoms. The study concluded that “proximity of natural gas wells may be associated with the prevalence of health symptoms including dermal and respiratory conditions in residents living near natural gas extraction activities” and that “further study of these associations, including the role of specific air and water exposures, is warranted.”  With respect to reported dermal symptoms, 13% of those within 2 kilometers of a well reported they had rashes and other skin symptoms, versus 3% of those beyond 2 kilometers.  For upper-respiratory symptoms, 39%, of those living less than a kilometer from a well reported upper-respiratory symptoms, compared with 18% living more than 2 kilometers away.

While these results were picked up with some attention-grabbing headlines–e.g., “Living near a fracking site DOUBLES the risk of developing lung and skin conditions, claims study“–the study authors noted several limitations.  Perhaps most notably, they concede that the results do not prove that the wells were the cause of the reported health symptoms; at most, the results are “hypothesis generating” and warrant further study.

Notably, at nearly the same time, the results of a study out of Penn State University titled “The fate of residual treatment water in gas shale” were published in the Journal of Unconventional Oil and Gas Resources (available here).  This study examined groundwater contamination concerns from hydraulic fracturing, and specifically whether water injected into wells that remains underground as residual treatment water or “RTW” (as opposed to the injected water that returns the surface as “flowback“) could find its way into groundwater and cause contamination.  The University’s press release on the study, titled “Residual hydraulic fracturing water not a risk to groundwater,” notes that such risk from RTW is low because the injected water that remains underground is sequestered in the rock formation.  More specifically, while “some have suggested that RTW may be able to flow upward along natural pathways, mainly fractures and faults, and contaminate overlying groundwater,” the study found that “ground water contamination is not likely because contaminant delivery rate would be too small even if leakage were possible, but more importantly, upward migration of RTW is not plausible due to capillary and osmotic forces that propel RTW into, not out of, the shale.” In short, the “RTW will be stably retained within the shale formation due to multiphase capillary phenomena.”  One of the authors of the study noted that “[t]he practical implication is that hydrofracture fluids will be locked into the same ‘permeability jail’ that sequestered overpressured gas for over 200 million years . . . . If one wants to dispose of fracking waters, one could probably not choose a safer way to do so than to inject them into a gas shale.”

Not surprisingly, the seemingly “conflicting” conclusions of the two studies was a focus of recent media coverage.  For example, a recent article–”Yale, Penn State studies offer conflicting views of fracking“–noted that “[t]wo academic studies exploring health and water issues in the gas drilling industry on Wednesday painted very different pictures of its potential impact and brought rebukes from advocates on both sides.”  With respect to the “rebukes,” the article notes that the Yale study has been criticized because of its backers:  “Travis Windle, a spokesman for the Marcellus Shale Coalition in North Fayette, said the Yale survey was ‘done in partnership with a local activist group, and was designed to put selective and unproven data behind a pre-determined and biased narrative.’”  And, not to be outdone, environmentalists said the Penn State study was “funded by the drilling industry” and “could not be trusted.”  They also criticized the more limited focus of the Penn State study, namely, “the narrow issue of water trapped in shale, instead of potential contamination by water that flows back to the surface during drilling and fracking.”  In a familiar refrain with respect to the science on fracking, the article notes that “[b]oth studies added to research that has yet to conclusively link the blossoming shale gas industry to health dangers or rule out such fears.”

On the heels of the Yale and Penn State studies comes another study looking into the potential impacts of natural gas operations on drinking water in North Texas’ Barnett Shale and the Marcellus Shale in Pennsylvania.  The study, authored by researchers at five universities (Ohio State, Stanford University, Duke University, Dartmouth College and the University of Rochester), was published in the Proceedings of the National Academy of Sciences.  As reported in The Dallas Morning News, the researchers sought to find the origin of natural gas found in water well samples and to determine how it got there.  The samples were taken from wells in western Pennsylvania’s Marcellus Shale and one in the Barnett Shale region in Texas.  By studying the isotopes found in the samples, the authors identified “signatures” indicating where the gas came from and how it reached the aquifers. In some cases, the authors determined that shale gas traveled up a gas well and then leaked into the aquifer through faults in the well.  While this finding again has generated headlines such as “Texas drinking water tainted by natural gas operations, scientists find”–what may be most significant is that the study found that neither the drilling itself nor the hydraulic fracturing that follows were directly to blame for the contamination.  Indeed, one of the study’s authors noted that “tracing the blame to well construction problems instead of fracking offers hope of protecting groundwater supplies” which is “relatively good news because it means that most of the issues . . . can potentially be avoided by future improvements in well integrity.”

As this roundup of only three recent studies shows, all aspects of fracking are under the microscope.  Studies are being published at a rapid pace, sometimes with indefinite conclusions — or conclusions that conflict with other studies.