Early research by chemists at the University of Texas at Arlington (UTA) has found abnormalities in well water in the Eagle Ford Shale region; however, further investigation is needed to determine the source and extent of contamination, they said.
Abnormal chloride/bromide ratios, as well as evidence of dissolved gases and "sporadic episodes of volatile organic compounds" were found, the UTA chemists said in announcing the research. The findings are "indicative of some contamination from industrial or agricultural activities in the area," they said.
"The infrequent detection of volatile organic compounds in the groundwater overlying the Eagle Ford Shale is certainly good news for citizens; however, there were instances of abnormalities on the water that we cannot quite explain," said Kevin Schug, a UTA professor of analytical chemistry and director of the university's Collaborative Laboratories for Environmental Analysis and Remediation lab.
Besides "two highly differentiated types of chloride/bromide ratios" in groundwater samples, water effervescence suggesting "dissolved hydrocarbon gases and a few volatile organic compounds in areas near oil and natural gas extraction sites" were also found.
"The next step in this research is to further characterize what these gases and chemicals are attributed to. Hopefully a closer collaboration with industry to gain a more intimate knowledge of the chemicals used during shale energy extraction will allow us to better assess whether or not unconventional oil and gas development is having a significant impact on groundwater quality in the south Texas region," Schug said.
The findings were published recently in Science of the Total Environment. Schug was joined by co-author Zacariah Hildenbrand of Inform Environmental and scientists from the University of North Texas. Tarleton State University and Ohio State University also contributed to the study.