Many Pennsylvania residents have said for years that the drinking water near fracking sites made them sick, David Trilling notes in Journalist's Resource, a service of the Shorenstein Center at Harvard University. The Environmental Protection Agency agreed in December 2016 that there is a connection between fracking and contaminated groundwater. The research from Hill and Ma answers the question of how far shale gas drillers need to stay away from drinking water.
Hill and Ma took 54,809 water samples over five years within 10 kilometers of a well pad, a group of wells. Trilling lists their takeaways:
- Adding a well pad within 0.5 kilometers of a water-intake location is associated with a 2.7 percent increase in fracking-related contaminants.
- Contaminants fall as the distance increases. A well pad within 1 kilometer is associated with a 1.5 percent increase in contaminants.
- Beyond 1 kilometer, the results are no longer statistically significant.
- A well placed uphill from a water source poses a slightly greater threat, providing “evidence that, unsurprisingly, it is the uphill threats that are disproportionately affecting drinking water quality.”