Methane leaks from shale gas drilling in Pennsylvania continue to decline, even with increased production and more wells going online, according to data from the state Department of Environmental Protection.
The agency on Monday reported decreases in total methane and carbon monoxide released into the air in 2013. Total nitrogen oxide, sulfur dioxide and volatile organic compounds from shale wells and processing plants increased during that time, though the average amount of those smog- and acid rain-producing pollutants from each source either fell or showed minor increases.
“The increases were not unexpected,” said acting DEP Secretary John Quigley, who noted the latest annual inventory included more sources. “The industry is growing, and each year, we are expanding the types and number of facilities from which we collect data so that we have a more comprehensive understanding of air quality issues.”
The report underscores a national trend of reduced drilling industry gas leaks. Concern about air quality remains a cornerstone in arguments surrounding how horizontal drilling and shale fracking affect the environment and the public’s health.
The issue is especially acute in Western Pennsylvania, where air quality continues to recover from the industrial past.
Environmental groups have pressured producers to further curb leaks from operations — especially methane, a greenhouse gas. Companies say they do what they can to make sure the gas pulled from the ground stays inside pumps and pipelines that transport it to market.
“We’re seeing decreased emissions with increased production, so obviously the industry is doing a better job of tightening up their ships,” said David Yoxtheimer, a researcher at Penn State University’s Marcellus Center for Outreach and Research.
Federal and state data show that greenhouse gas emissions from the industry continue to decrease even as Marcellus shale gas production more than doubled, from 2.37 trillion cubic feet in 2012 to a record 4 trillion cubic feet in 2014.
The Environmental Protection Agency has reported a 79 percent decrease in methane emissions from well sites and hydraulic fracturing operations from 2005 to 2013. Proposed federal rules would cut leaks by nearly half during the next decade.
Total methane emissions from well sites and midstream facilities reported to the DEP decreased by 13 percent from 2012 to 2013, the most recent year data were collected; on a per-source basis, the average fell by 26 percent from 16.63 tons per site to 10.08.
Overall nitrogen oxide emissions grew by 8 percent, though the average source’s emissions fell by about 8 percent, from 1.8 tons per source to 1.65. When released into the air, nitrogen dioxide can form nitric acid and cause acid rain.
Sulfur dioxide and fine particulate matter emissions increased overall, though their numbers represent a fraction of other pollutants. Volatile organic compound emissions increased by 19 percent overall, though the per-source increase was less than 1 percent.
The gas industry says it is investing in equipment to protect against leaks.
“The sharp decline in methane emissions, despite increased activity, is particularly encouraging and reinforces the fact that our strong state-based regulations and innovative technologies are delivering meaningful environmental results,” said Dave Spigelmyer, president of the North Fayette-Marcellus Shale Coalition, the industry’s biggest lobbying group.
State and federal laws rely on gas companies to report the emissions data, which can be problematic without third-party verification, said Rob Altenburg, director of Penn Future Energy, an environmental group based in Harrisburg.
“We’ve found some inconsistencies in reporting,” he said.
The decreases in leaks are a result of increased government oversight, he said.
“It’s not surprising that that is going to show a decrease,” he said. “Regulation does work.”
Environmentalists say federal regulations announced in 2012 to require more environmentally friendly well completions have helped reduce emissions at the well head.
Several drillers and midstream companies across the Marcellus including EQT, Range Resources Corp., Cabot Oil & Gas, and Southwestern Energy have reported their own decreases in methane and other emissions.
Southwestern Energy, based in Houston, is helping to organize a coalition to drop the industry’s leak rate to no more than 1 percent. The ONE Future Coalition includes eight companies and is collecting data to study leaks, said Sarah Battisti, a Southwestern spokeswoman.
The latest Pennsylvania snapshot of emissions does not include potential leaks from tens of thousands of conventional gas wells. Those wells emit gas at lower pressures than shale wells but their number could affect overall greenhouse gas emissions, Yoxtheimer, the Penn State researcher, said.
This article was written by Katelyn Ferral from The Pittsburgh Tribune-Review and was legally licensed through the NewsCred publisher network.