UTA continues to lead investigations into the effects of unconventional oil and gas extraction processes on groundwater quality.
New research demonstrates that groundwater quality changes with the expansion of horizontal drilling and hydraulic fracturing-but it also suggests that some potentially hazardous effects may dissipate over time.
A UTA team collected and analyzed private well water samples on the eastern shelf of Texas' Permian Basin to monitor basic water quality, metal ions, organic ions, and other chemicals. They discovered the presence of chlorinated solvents, alcohols, and aromatic compounds exclusively after multiple unconventional oil wells had been activated within five kilometers of the sampling sites.
"These changes and levels are abnormal for typical groundwater quality," says Kevin Schug, Shimadzu Distinguished Professor of Analytical Chemistry and director of UTA's Collaborative Laboratories for Environmental Analysis and Remediation.
"The results also suggest that contamination from unconventional drilling may be variable and sporadic, and that some of the toxic compounds may become diluted within the aquifer over time," he continues. "The next step is more research to precisely quantify and understand contamination cycles as well as aquifer resilience to pollutants."
In a related study of well water quality in the Eagle Ford Shale region, Schug and his team found abnormal chloride/bromide ratios, alongside evidence of dissolved gases and sporadic episodes of volatile organic compounds-all indicative of some contamination from industrial or agricultural activities in the area.
Both studies were published this year in Science of the Total Environment.