The EPA will cede authority to Wyoming regulators in a landmark investigation to determine whether hydraulic fracturing contaminated groundwater, according to a release from Wyoming Governor Matt Mead.

In December 2011, the EPA found chemicals in the groundwater near Pavillion, Wyo. that were "consistent with gas production and hydraulic fracturing fluids, benzene concentrations well above Safe Drinking Water Act standards and high methane levels."

We wrote about the case in October, when the EPA said new USGS data confirmed those findings.

Shortly thereafter, we talked to Pavillion-area residents who explained how local hydrocarbon deposits were extremely shallow and that they'd long accepted that their water had an usual taste.

Last month, we rounded up instances around the country where regulators had been effectively bullied into easing up on fracking investigations, though there is no evidence that has occurred in this instance.

The Wyoming Department of Environmental Quality (WDEQ) and the Wyoming Oil and Gas Conservation Commission (WOGCC) will now lead the Pavillion effort, the governor's release said.

“I commend the EPA and Encana for working with me to chart a positive course for this investigation," Mead said. "I commit that Wyoming will work in a thoughtful and productive manner as further investigation is initiated.”