The Sierra Club, Earthworks and the Natural Resources Defense Council said they confirmed, with the help of an independent expert, that an EPA study in Wyoming highlighted the risks associated with hydraulic fracturing.
Energy companies working shale natural resources utilize hydraulic fracturing, known also as fracking. The process uses abrasives and chemicals to extract natural resources from rock formations. Some of the chemicals are considered harmful to the environment.
The Environmental Protection Agency said it found levels of glycols and other synthetic chemicals associated with fracking in monitoring wells in Wyoming. Its draft report in December found chemicals in monitoring wells were "well above" drinking water standards.
The EPA report said chemical levels in Wyoming aquifers were "generally below established health and safety standards" in actual drinking water.
"This report raises the alarm on the public health threats posed by dirty and dangerous fracking and the need to rein in a oil and gas industry that remains unchecked and unaccountable for their toxic pollution," Deb Nardone, a natural gas campaigner for Sierra Club, said in a statement.
However, Energy in Depth, a group formed by several energy-industry organizations, said is found more than 50 individual measurements in the EPA report that were discredited by the USGS.
Wyoming Gov. Matt Mead, who backs pro-coal legislation, said state policy would be "guided by science."