"Advocates state that fracturing has been performed safely without significant incident for over 60 years," the report said. "Opponents point to failures and accidents and other environmental impacts, but these incidents are typically unrelated to hydraulic fracturing per se and sometimes lack supporting data about the relationship of shale gas development to incidence and consequences."
Panel members blamed some of this "difference in perception" on "communication issues."
"Many in the concerned public use the word 'fracking' to describe all activities associated with shale gas development," the report said, "rather than just the hydraulic fracturing process itself."
The report noted that the U.S. Environmental Protection Agency is undertaking a two-year study -- ordered by Congress -- to investigate the potential impacts of hydraulic fracturing on drinking water resources.
The advisory panel report said, "The subcommittee shares the prevailing view that the risk of fracturing fluid leakage into drinking water sources through factures made in deep shale reservoirs is remote."
"Regulators and geophysical experts agree that the likelihood of properly injected fracturing fluid reaching drinking water through fractures is remote where there is a large depth separation between drinking water resources and the producing zone," the report said. "In the great majority of regions where shale gas is being produced, such separation exists and there are few, if any, documented examples of such migration."
But the panel also said, "An improperly executed fracturing fluid injection can, of course, lead to surface spills and leakage into surrounding shallow drinking water formations. Similarly, a well with poorly cemented casing could potentially leak, regardless of whether the well has been hydraulically fractured."
The report said, though, that methane leaking from producing wells into surrounding drinking water wells "is a greater source of concern," that needs more study and more attention from the industry.
Panel members said such methane migration could most likely be blamed on drilling in a geologically unstable location or on poor casing or production practices.
More testing and more frequent inspections are needed to guard against such unsafe practices, the panel said.
"The public deserves assurance that the full economic, environmental and energy security benefits of shale gas development will be realized without sacrificing public health, environmental protection and safety," the report said. "Accidents and incidents have occurred with shale gas development, and uncertainties about impacts need to be quantified and clarified."
Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.