By Timothy Puko
Published: Monday, September 16, 2013 10:45 p.m.
Updated 9 hours ago
A nationwide study has made what may be a big first step in settling important questions over the gas boom’s impact on climate change, suggesting that natural gas wells probably don’t leak as much air pollution as previous worst-case estimates indicated.
The findings, which were published Monday by the Proceedings of National Academy of Sciences, imply that the gas industry’s emissions may be low enough that the world could reduce its heat-trapping pollution in the atmosphere by burning more gas and less coal.
Although the news is encouraging, there still is a lot of work left to draw a more definitive conclusion, said officials at the Environmental Defense Fund, an environmental group that collaborated with the gas drilling industry to do the research.
The study is the first of 16 the group is coordinating on methane leaks from the expanding natural gas industry. Researchers still have to finish studying leaks from other vulnerable parts of the industry — from processing plants to pipes.
“In order to definitively answer the question ‘Is this better than coal?’ we need to have the information from the time it comes out of the ground to the time you burn it,” said Drew Nelson, the group’s clean energy project manager. “We don’t have that information yet.”
Nelson said the results were encouraging, in part, for the environment, but he said that the research pointed out other parts of a well site that were more vulnerable to leaks than previously expected.
“You’re getting at the heart of one of the central questions,” said Andrew Place, an industry scientist who is interim director of the Center for Sustainable Shale Development, Downtown. “It’s not the end of the story, but it’s an important initial piece for the public’s understanding of the importance of natural gas, shale gas in particular.”
The results generally agree with earlier Environmental Protection Agency estimates.
Nine drillers — including Chevron and subsidiaries of Shell and Exxon-Mobil that work in the Marcellus shale — funded most of the $2.3 million effort, Nelson said. The Environmental Defense Fund paid $230,000, an equal share as all the other companies. It helped academics led by the University of Texas to sample 190 natural gas wells nationwide, the broadest effort ever to collect samples from the well sites themselves.
The impact on climate change is one of the major unresolved questions surrounding the rapid growth of hydraulic fracturing — fracking — happening in shale formations like the Marcellus in Pennsylvania and worldwide. Several scientists said the new information is a big first step in dispelling those fears.
Shale drillers have promoted their product as cleaner-burning energy than oil and coal, but some scientists have challenged the assertion. Some research claimed leaks from the thousands of new wells and miles of pipe nationwide would more than offset any gains.
Part of the disagreement came from a lack of real samples and data from the drill sites, which required industry collaboration. Robert Howarth of Cornell University, one of the scientists who first raised the methane leak alarm, complimented the study. But he warned that this could be just the “best-case scenario” from careful drillers working while being watched.
Officials at the Environmental Defense Fund hope to have a final answer by sometime in 2014, they said.
Timothy Puko is a staff writer for Trib Total Media. He can be reached at 412-320-7991 or firstname.lastname@example.org. The Associated Press contributed to this report.