EPA’s Fracking Study Bolsters Energy Industry, Undercuts Environmentalists

"I think this report effectively kills those bills," Nettles said.

The report is also a boost for President Barack Obama's reliance on natural gas to achieve cuts in greenhouse-gas emissions from power plants, an effort that's the mainstay of his agenda to combat climate change.

Obama Policy

"It's quite clear that the Obama administration remains committed to the all-of-the-above energy plan, of which natural gas is a huge part," said Lauren Pagel, policy director for Earthworks, an anti-fracking group. "I don't think the Obama administration would ever come out against fracking."

The Obama administration in March issued fracking regulations for drilling on public land, requiring drillers to reveal the chemicals they use and to meet construction standards for wells. Most of oil and natural gas production, however, occurs on private lands and isn't affected by the rule.

Stanford University professor Rob Jackson has tested water supplies in communities where residents said they had contaminated supplies, and found there are risks from the process but not insurmountable ones. The EPA study doesn't add much to that and other on-the-ground research, he said.

The EPA could never come to terms with gas producers such as Range Resources Corp. or Chesapeake Energy to conduct water tests near where wells were to be drilled and fracked, and then go back and re-test afterward. Without that baseline data, the EPA said it's hard to tell if fracking is the cause in instances of alleged contamination.

Waste Disposal

In addition, when the study began much of the focus was on the risk that chemicals mixed in fracking fluids could flow through underground fissures and into underground water reservoirs. The results show that might not be the biggest risk.

"The process of fracking itself is one risk factor. But in fact it's not the biggest one," said Mark Brownstein, vice president of the Environmental Defense Fund. "Ongoing physical integrity of the wells and handling the millions of gallons of wastewater coming back to the surface after fracking, over the lifetime of each well, are even bigger challenges."

And the biggest worry now about fracking, is one that has nothing to do with the process itself. Residents in Oklahoma, Ohio and other states have seen more and more earthquakes, which researchers tied to the increasing use of disposal wells for the wastewater from fracking.

"The water quality issue is not the primary problem with fracking impacts, it's seismicity," said Paul Bledsoe, president of Bledsoe & Associates, a strategic policy firm, and a former aide to President Bill Clinton.

–With assistance from Bradley Olson in Houston.