New DEP Data Show Methane Emissions Continue to Decrease, Air Quality “Continues to Improve”
The Pennsylvania Department of Environmental Protection (DEP) has just released data from its 2014 air emissions inventory of the natural gas industry. While there was “a slight (1%) increase in reported methane emissions” from 2013 to 2014, methane emissions have still significantly decreased, almost 12 percent from 2012 to 2014. That’s all happening as natural gas production ramps up: as the DEP press release explains, “unconventional gas wells increased significantly, from 3.1 trillion cubic feet of gas to 4.1 trillion cubic feet” – that’s a 33 percent increase in production.
The data also show some levels of air emissions during production slightly increasing, but as DEP Acting Secretary Patrick McDonnell explains, the bigger picture is that the state’s greater use of natural gas has led to dramatic decreases in air pollution:
“Although the reported emissions from the natural gas sector increased in 2014, overall our air quality continues to improve due to emissions reductions from other point sources such as electric generating units,” McDonnell said. “Between 2011 and 2014, NOx and SO2 emissions from electric generating units have decreased by 18 percent (27,246 tons per year) and 17 percent (54,973 tons per year), respectively. We remain committed to developing and implementing the most effective ways to control and reduce emissions from Pennsylvania’s natural gas sites.” (emphasis added)
DEP has previously highlighted that the emission reductions from the state’s increased use of natural gas represent “between $14 billion and $37 billion of annual public health benefits.” Then DEP Secretary Chris Abruzzo pointed out:
“It is important to note that across-the-board emission reductions … can be attributed to the steady rise in the production and development of natural gas, the greater use of natural gas, lower allowable emissions limits, installation of control technology and the deactivation of certain sources.” (emphasis added)
It’s also worth noting that much of the increase in emissions can be attributed to the fact that the “number of midstream facilities that submitted data in 2014 increased by 12 percent,” as the press release also states. Actually, if you look at the data from 2011 to 2014, midstream facilities increased by 239 percent. Of course, midstream facilities receive permits to release a certain level of emissions to maintain safe levels in the working environment – and these releases are highly regulated.
It’s also important to point out that the data were not obtained by measurements from air monitors – and studies that do evaluate direct measurements have shown very low emissions. A study by the National Oceanic and Atmospheric Administration (NOAA) found that methane leakage rates from the Marcellus Shale were 0.18 to 0.41 percent, which is exceedingly low.
A recent Pennsylvania report commissioned by Fort Cherry School District in southwest Pennsylvania examined air emissions at a nearby well site in Washington County — the state’s most active shale county — and “did not show anything remarkable with respect to chemicals detected in the ambient air.”
Another recent Marcellus study led by researchers at Drexel University found low levels of air emissions at well sites. As they explained, “we did not observe elevated levels of any of the light aromatic compounds (benzene, toluene, etc.)” and “there are few emissions of nonalkane VOCs (as measured by PTR-MS) from Marcellus Shale development.”
While some activists may try to twist the facts, DEP’s data show that methane emissions are decreasing as natural gas production soars – and the increased use of natural gas continues to reduce pollution across the state.