Professor Rob Jackson and his colleague have published a new study looking carefully at methane levels and characteristics in 141 water wells in 6 counties in Northeast Pennsylvania. The study is published in the Proceedings of the National Academy of Sciences. Importantly, the study was funded by Duke University and two donors to Duke University, but neither by industry nor foundations funding its opponents. Since Duke University has funded this research done by its professors, its appropriate to say this is a "Duke" study.
The study finds significant evidence that mistakes in gas drilling--either in casing or cementing--have caused stray thermogenic methane gas to contaminate some water wells. In this respect, this study's results are consistent with the findings in 2010 of the Pennsylvania Department of Environment Protection that gas drilling mistakes had caused methane to contaminate 18 water wells in Dimock, Pennsylvania.
Much of the evidence for Jackson's conclusion that stray gas from mistakes in gas drilling have caused pollution of water wells stems from analysis of the methane found in water wells and high concentrations of ethane and propane, both of which are not associated with microbes or biogenic natural gas. Jackson also finds a statistically significant correlation between the distance of a water well from gas drilling and concentrations of methane in the 141 water wells.
Here is the Associated Press report on the Duke University study that also mentions a USGS study that found many water wells in areas where no gas drilling takes place have methane of various levels in them.
Professor Jackson also states in the AP story that Duke University continues to find no evidence of fracking fluids in water wells. That too has been the finding of testing done by the Pennsylvania Department of Environmental Protection in 2010 and the Environmental Protection Agency in 2012.
So what to make of the Duke University and USGS studies?
First, gas drilling mistakes in cementing or casing can and have caused stray methane to migrate and contaminate some water wells. I have been saying that now repeatedly for four years! Denying this problem attacks the truth and is a disservice especially to those whose water has indeed been contaminated with methane.
Second, many water wells do have methane in them as a result of its natural presence in varying levels in some waters. In fact, naturally occurring methane in water is relatively common in some areas, but that does not mean that mistakes in gas drilling cannot cause methane to pollute water wells. Such drilling mistakes can and do.
Third, fracking fluids are not returning from depth and contaminating water wells.
Finally, I am pleased that Duke University (I graduated from it in 1979) used its own resources to fund this study. This is an example that other wealthy universities should follow!