A federal Environmental Protection Agency study has for the first time determined that hydraulic fracturing, used in oil and gas development throughout the United States, has contaminated water supplies in isolated incidents but has not caused widespread, systematic damage to water resources.
The study, ordered by Congress in 2010, concluded that the number of actual problems caused by the process was relatively small compared to the thousands of wells that have been drilled. Hydraulic fracturing involves pumping millions of gallons of water mixed with chemicals and sand deep underground under high pressure to crack shale formations and release the gas and oil it holds.
But the study also identified a series of “vulnerabilities” created by the process. Those vulnerabilities or risks include: water withdrawals from limited water sources; groundwater contamination; inadequate well cementing and casings that allowed migration of gas and liquids into drinking water aquifers; releases of inadequately treated wastewater; and surface spills of chemical fracking fluids and wastewater.
The report does acknowledge, unlike a 2004 EPA study, that the fracking process has contaminated water supplies.
“I think the study recognizes instances where fracking activity impacted surface and groundwater,” said Thomas Burke, EPA’s science advisor and deputy assistant administrator of the agency’s Office of Research and Development. He answered questions during a phone-in news conference that followed the release of the report Thursday.
Mr. Burke said the study “followed the water” through collection, use, flowback and disposal and found instances of fracking releasing methane gas that strayed into groundwater and the release or leaking of fracking wastewater from surface impoundments that contaminated surface and groundwater.
John Quigley, secretary of the state Department of Environmental Protection, said that while the Marcellus Shale gas boom has not had a significant impact on Pennsylvania’s water resources, the department is strengthening oversight to reduce the risks identified in the EPA sturdy.
In the last decade, use of fracking has expanded in Pennsylvania and more than two dozen shale formations across the U.S., where it has come under fire by environmentalists and some residents in shale gas development areas because of concerns it can contaminate surface and groundwater.
The EPA study looked at fracking operations in many areas of the country, including Pennsylvania. Its review of past contamination complaints in Bradford and Susquehanna counties found that while methane occurs naturally in water supplies throughout the area, stray gas associated with nearby drilling activities into the Marcellus Shale formation had infiltrated as many as nine of the 36 drinking water wells sampled, and a well pad spill may have contaminated a pond with salts.
Mr. Burke said the EPA study is based on the most complete compilation of scientific data to date, including more than 950 published papers, numerous technical reports and information from industry and environmental stakeholders.
“Once final, EPA’s draft assessment will give state regulators, tribes and local communities and industries around the country a critical resource to identify how best to protect public health and their drinking water resources,” Mr. Burke said.
Drilling and oil and gas industry organizations touted the report’s findings as an affirmation of industry production practices and the adequacy of existing state regulations.
“We are very pleased with EPA’s findings, which not only reflect the strong, rigorous and modernized regulations in place that ensure environmental protection but also the industry’s focus and commitment to continuous operational improvements, especially related to groundwater protection and effective water management best practices,” said Marcellus Shale Coalition President Dave Spigelmyer in a written release.
Environmental organizations said the report shows there is mounting evidence that fracking poses an ongoing and potentially dangerous risk to vulnerable drinking water supplies. “EPA’s assessment should inspire a pause in hydraulic fracturing and more reflection on its environmental impact,” said Mary Greene, a senior attorney with the Washington, D.C.-based Environmental Integrity Project, in a news release.
The draft study will be published in the Federal Register today, reviewed by the EPA’s Science Advisory Board and subject to a public comment period before it is finalized. A copy of the EPA's draft assessment report can be found at www.epa.gov/hfstudy.
Don Hopey: dhopey@post-gazette.com, 412-263-1983 or on Twitter: @donhopey Laura Legere: llegere@post-gazette.com.
First Published: June 4, 2015, 6:12 p.m.
Updated: June 5, 2015, 2:56 a.m.
