The U.S. Chamber of Commerce has petitioned the Environmental Protection Agency (EPA) to revise information in a 2010 document that "erroneously overestimates" methane emissions, volatile organic compounds (VOC) and hazardous air pollutants (HAP) associated with shale gas well completions.
In a 2010 technical support document, "Greenhouse Gas Emissions Reporting from the Petroleum and Natural Gas Industry," the EPA "altered the methodology it had previously used to estimate...emissions from completion of natural gas wells and found that 9,175 Mcf of natural gas and its associated methane, VOCs and HAPs are emitted from the completion of unconventional shale gas wells," the Chamber told the EPA.
"The well completion emission factor of 9,175 Mcf/completion in the 2010 [document] is an overestimate of emissions from the natural gas industry" because it is based on "faulty assumptions," the Chamber said. Two of the incorrect assumptions are: gas emissions are controlled by green completions for only 15% of gas well completions; and gas is vented for 49% of the nongreen well completions, it noted.
Green well completions take place during the clean-up stage of the completion, after a well has been hydraulically fractured (fracked). The clean-up involves removing the water necessary to frack the well. During this flow back, natural gas is produced with the water. What makes the well completion "green," or environmentally friendly, is that the gas is separated from the water and placed in a pipeline instead of being released into the atmosphere.
IHS CERA, a well known energy research firm, also concluded that the "overall amount of methane that EPA assumes is emitted during well completion activities does not pass a basic test of reasonableness," according to the Chamber. And San Francisco-based URS Corp., which conducted a survey of gas well completions and emissions, reported that the survey results showed that actual gas emissions from the completion of unconventional shale gas wells were more than 1,200% lower than EPA's gas emission estimate.
"The Chamber recommends that EPA correct its erroneous calculations within 90 days and return to the methane emissions estimates it used prior to the 2010 Greenhouse Gas Emissions Reporting from the Petroleum and Natural Gas Industry technical support document.
"Inaccurate estimates by a government body are highly problematic because policy decisions are made in reliance on the trust supposedly inherent in EPA's data. In fact, critical regulatory initiatives and proposals are being based, in part, on EPA's flawed estimates. Currently the proposed new source performance standards for the oil and natural gas industry are founded in part on what are now seen to be EPA's seriously inflated estimates of methane, VOC, HAP emissions from unconventional shale gas well completions," the Chamber noted.
"These faulty assumptions affect the Chamber's members in the natural gas extraction industry through increased production costs, and affect all users of natural gas through increased energy prices and the resulting impact on jobs."