EPA methane emission methods questioned
Two Republican senators urged the U.S. Environmental Protection Agency (EPA) to reconsider its methods of calculating methane emissions from natural gas operations.
Sens. David Vitter (R-LA) and James Inhofe (R-OK) praised a report released in September that said some parts of the gas production process actually emit less methane than EPA estimated. The study also noted the leaks from pneumatic controllers involved higher methane emissions than EPA estimates, saying they need to do more study on the subject. The comments came during a hearing of a subcommittee on oversight of the Senate Committee on Environment and Public Works on Nov. 5 in Washington, DC.
The Environmental Defense Fund and nine gas operators funded the ongoing study, which measured actual emissions from 190 wells instead of relying on computer models as does the EPA.
A report outlining first-phase results of a University of Texas study concluded the methane emissions from operations associated with gas production overall is 10% less than the EPA estimates.
University of Texas chemical engineering professor David Allen and other researchers measured methane emissions from shale gas wells completed using hydraulic fracturing. Initial study results involved only the gas extraction phase, Allen testified at the subcommittee hearing.
EPA representative Sarah Durham told Vitter and Inhofe that she could not answer their questions yet about whether the UT study would alter EPA’s estimates or change EPA methods of estimating greenhouse gases. She would only say the EPA was reviewing and evaluating the study.
Durham, director of the Office of Atmospheric Programs within the EPA’s Office of Air and Radiation, also said she could not directly answer questions about the study’s impact on future GHG emission regulations, saying she was not associated with the regulatory branch of the EPA.
Other subcommittee witnesses included Mark K. Boling, general counsel for Southwestern Energy Co., and Darren Smith, environmental manager for Devon Energy Corp.
Smith said the UT study confirmed what Devon has been telling the EPA for some time.
“Immediate action is vital because the EPA estimates have been relied upon by researchers, financial analysts, and various policy makers as a basis for critical public policy considerations,” Smith said.
“In fact, a recently finalized EPA regulation on the oil and gas sector was justified using this inaccurate data,” Smith said. “Equally troubling, a group of Northeastern states is threatening to sue the EPA if it doesn’t propose additional emissions regulations on the sector, in light of the agency’s use of flawed data. EPA must immediately revise its data to more accurately reflect emissions associated with this source category, before further harm is done.”