Marcellus Shale Air Monitoring Study

HARRISBURG, PA — The Department of Environmental Protection (DEP) announced it has started a long-term, one-year air monitoring study of Marcellus Shale development. The study in Washington County will measure ambient airborne pollutants in an effort to determine potential air quality impacts associated with the processing and transmission of unconventional natural gas.

“We operate on facts and sound science, and this study will provide us with data on long-term air quality in an area of active natural gas extraction,” DEP Secretary Mike Krancer said. “There has been a documented downward trend in airborne pollutants across the state over the past 10 years, and Marcellus Shale development holds the promise of emissions benefits from the use of this cleaner-burning fuel in the transportation and electricity generation sectors.”

The data from the study will allow DEP to assess any potential long-term impact of air emissions from unconventional natural gas operations to nearby communities, and it will help DEP address the cumulative impact of the operations in the Marcellus Shale region.

In 2010 and 2011, the agency conducted short-term ambient air quality sampling in the southwest, north-central and northeast parts of the state, where Marcellus Shale drilling was taking place. The sampling did not identify concentrations of any compound that would likely trigger air-related health issues. DEP also tested for carbon monoxide, nitrogen dioxide, sulfur dioxide and ozone, but did not detect concentrations above National Ambient Air Quality Standards at any of the sampling sites.

The primary site of the long-term study will be downwind of the Houston gas processing plant in Chartiers Township, Washington County, where DEP will monitor for ground-level ozone, particulate matter, carbon monoxide, nitrogen oxides, hydrogen sulfide and methane. The ambient air will also be tested for more than 60 volatile organic compounds, including hazardous air pollutants, and meteorological data will be collected continuously.

DEP will also monitor for volatile organic compounds and collect meteorological data at three additional sites in Chartiers Township and Hickory Township, Washington County. Of the two additional Chartiers Township sites, one is upwind of the Houston gas processing plant, and the other is downwind of the Brigich compressor station. The site in Hickory Township will be located downwind of the Stewart compressor stations.

DEP intends to collect at least one year of data and compare those results to national ambient air quality standards, then conduct a long-term risk analysis. The Washington County results and risk analysis will aid in determining the need for any further long-term sampling in other regions of the state.

For more information or to view the study’s sampling protocol, visit www.dep.state.pa.us and click “Air,” or call 717-787-9702.