Is Fracking Making Air Quality Better or Worse?

  • Emissions from Marcellus Shale gas wells in Pennsylvania may have a strong local impact, according to a recent study. Photo: Reid R. Frazier

April 11, 2014

Pennsylvania is reporting some types of air pollution from natural gas drilling are on the decline. But a new study in Washington County, Pennsylvania finds those living near gas drilling may be experiencing high spikes in air pollution.

The study adds to an emerging picture of the impact of Pennsylvania’s natural gas boom on air quality. Backers of the industry, including the state’s Department of Environmental Protection, say statewide data show the decline in coal-fired power plant emissions and increase in the use of natural gas for electric generation are having a beneficial effect on air quality in Pennsylvania.

But other evidence points to increased pollution threats for those near wells and compressor stations.

A new study, published in the journal Reviews on Environmental Health measured indoor air quality in 14 homes in Washington County, near drilling sites. The authors found these homes often experienced spikes in particulate matter (PM 2.5) that would last one to two hours. Sometimes these spikes would be two or three times over the federal 24-hour limit for PM 2.5, said the study’s lead author, David Brown, toxicologist for the Southwestern Pennsylvania Environmental Health Project (the group is supported by the Heinz Endowments, which also supports the Allegheny Front).

Local Air Impacts Examined

Brown said the study highlighted what he sees as a disconnect between air quality data reported by federal and state regulators and actual health risks for those near fracking operations. The paper cites studies reporting people near fracking sites in other states at greater risk for cancer and low birth-weight. .

Brown says the way air quality is measured doesn’t do justice to the impacts of drilling activity, particular short bursts of pollution. That’s because air quality is usually measured over 24-hour increments, not shorter time frames. He said the 24-hour data may make the air look safe, but he said that can be deceiving.

“Health effects occur in a relatively short amount of time—an hour, two hour exposure, is enough to produce a health effect,” Brown said.

Brown says an air quality reading that falls within the EPA standards may mask occasional spurts in emissions stemming from venting or flaring of wells, leaks in valves, or other periodic pollution.

Shale Gas Emission Numbers Mixed

The study came out around the same time as new data from the state’s air pollution reporting system showed some declines in air emissions from fracking.

The Pennsylvania Department of Environmental Protection (DEP) reported that nitrogen oxides and sulfur dioxide emissions from fracking operations at 8,800 wells and over 400 comperessor stations were lower in 2012 than 2011.

But the data also show slight increases in particulate matter, and a 42 percent increase in volatile organic compounds. VOCs can form ozone, which can impact asthma and respiratory diseases, but some, like benzene, are hazardous air pollutants, and have been shown to cause cancer.

Some of the increase may stem from the fact that more compressor stations were required to report their emissions in the latest data.

In spite of these emissions, the DEP says the overall picture for air quality in Pennsylvania is getting better. The department pointed out that the electric generation sector in Pennsylvania in 2013 generated 23 percent less nitrogen oxides and 46 percent less particulate matter than it did in 2008, when natural gas drilling began rapidly increasing. 

“It is important to note that across-the-board emission reductions in emissions 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,” DEP secretary Chris Abruzzo said, in a release. 

The DEP also noted that some of the emissions from fracking may be reduced in the near future, as new mandates for pollution-reducing equipment at fracking operations go into effect.