The U.S. Department of Energy advisory panel downplayed the chances that large-scale "fracking" to release gas reserves deep underground would directly pollute drinking water from shallow groundwater supplies.
But the team also warned shoddy industry practices such as poorly cemented well casings could easily leak contaminants and urged a broader examination of the overall impacts of gas booms like the one hitting West Virginia's Marcellus Shale formation.
"Intensive shale gas development can potentially have serious impacts on public health, the environment and quality of life -- even when individual operators conduct their activities in ways that meet and exceed regulatory requirements," said the 41-page report from a Secretary of Energy Advisory Board subcommittee appointed by Energy Secretary Steven Chu.
"The combination of impacts from multiple drilling and production operations, support infrastructure (pipelines, road networks, etc.) and related activities can overwhelm ecosystems and communities," the report said.
Panel members urged federal, state and local regulators to "place greater effort on examining these cumulative impacts in a more holistic manner."
"Discrete permitting activity that focuses narrowly on individual activities does not reach to these issues," the report said.
The report's findings are significant in part because six of the panel's seven members have financial ties to the gas industry, including chairman John Deutch, an MIT chemist and former CIA director who previously served on the boards of two energy companies. On Wednesday, 28 scientists from 22 universities in 13 states had urged Chu to appoint a new chair to ensure the group's work was "unbiased and scientifically sound."
"The committee appears to be performing advocacy-based science and seems to have already concluded that hydraulic fracturing is safe," the scientists said in their letter. "We believe that the best science should be done first to determine whether increased unconventional gas production is sufficiently safe -- from the individual water well to climate impact -- and that policy should follow."
In its report, the panel called natural gas "the cornerstone of the U.S. economy," and praised "breakthroughs in technology" that have "brought lower prices, domestic jobs and the prospect of enhanced national security due to the potential of substantial production growth."
And parts of the report echoed industry complaints that drilling critics and the media misstate the impacts of the gas boom, especially regarding larger-scale hydraulic fracturing.