CFR: An Enlightening Study on Shale Gas and Water Quality

A team at Resources For the Future (RFF) led by Sheila Olmstead has a neat new paper in the Proceedings of the National Academy of Sciences (PNAS) that takes a rigorous look at water pollution due to shale gas development in Pennsylvania. (Hat tip: John Quigley.) The team collected thousands of data points measuring shale gas activity and water quality across a wide geographic area and more-than-ten-year span, and then used careful statistical analysis to test a series of hypotheses about how shale gas development might have affected water quality. What’s particularly interesting about this study is that it doesn’t require physical assumptions. It can also shed light on the cumulative impacts of large-scale shale gas development, going beyond analysis at the level of single pads and wells.

The team’s conclusions are fairly straightforward. They find enhanced chlorine concentrations downstream of waste water treatment facilities but not downstream of drilling sites. Chlorine is a good marker of contamination from well flowback. What the RFF analysis suggests is that leaks or spills aren’t statistically detectable, at least at the watershed level, but that impacts of poorly processed wastewater are. That points to the value of focusing on wastewater treatment facilities if one wants to reduce the impact of chemical contamination resulting from shale gas development. The authors are clear to point out that Pennsylvania has made significant changes in the last couple years in how it handles wastewater; whether those are sufficient given the costs and benefits of additional controls remains to be seen.    MORE

READ: Impacts of Shale Gas Development on Rivers and Streams