A new study by a Yale University professor further confirms what federal agencies have been reporting for years: Fracking hasn’t contaminated groundwater.

 Desiree Plata of the Yale School of Engineering and Applied Science spent three years collecting and analyzing drinking water from 64 sites in northeast Pennsylvania, conducting one of the largest such studies ever.

 So prolific was fracking in the area that “towards the end of our study, it was difficult to find a home that was more than a few kilometers from a natural-gas well-production pad,” she told National Public Radio.

 Nonetheless, Plata found that the water consistently met drinking-water standards. And any minute traces of contamination were likely caused by ground-level spills not unique to energy extraction—and decidedly not caused the fracking process itself.

 The Yale study wasn’t the first to make this claim; even the U.S. Department of Energy and the Environmental Protection Agency have admitted that the evidence does not suggest a correlation between fracking and groundwater contamination.

 But regardless of the science, anti-fracking activists continue publicizing this myth. The Yale study serves as a rebuke to their ungrounded allegations.