DEP Issues Report on Short-Term Air Quality Impacts from Marcellus
Shale Operations in Southwest PA
Agency Continues to Monitor Air Quality in Other PA Regions
PA-DEP Release
1 November 2010
COMMONWEALTH OF PENNSYLVANIA
Dept. of Environmental Protection
Commonwealth News Bureau
Room 308, Main Capitol Building
Harrisburg PA., 17120
FOR IMMEDIATE RELEASE
CONTACT: Katy Gresh, Department of Environmental Protection Southwest
Regional Office, 412-442-4203
HARRISBURG -- Department of Environmental Protection today released a
report on a five-week air quality study conducted near Marcellus Shale
natural gas operations in southwestern Pennsylvania’s Greene and
Washington counties.
“This short-term study only provides a snapshot of the air contaminants
we found at surveyed sites, but the data shows no emission levels that
would constitute a concern to the health of residents living near these
operations," DEP Secretary John Hanger said, noting that the report
does not assess the potential cumulative effects from natural gas
operations.
“These results only provide preliminary information about the type of
pollutants released to the atmosphere. Drilling activity continues to
increase at a rapid pace across the state, so this study provides us
with good information as part of our ongoing effort to gauge the impact
these operations have on our air quality, public health and the
environment. Needless to say, we plan to conduct more of these types of
air-sampling exercises moving forward,” Hanger added.
DEP’s assessment focused on concentrations of volatile organic
compounds, including benzene, toluene and xylene, which are typically
found in petroleum products. The department also sampled for other
pollutants including carbon monoxide and nitrogen dioxide near natural
gas extraction and processing sites.
The agency gathered samples to provide background data at its
monitoring station in Florence, a section of Hanover Township,
Washington County.
The air monitoring surveys near natural gas operations were conducted
at a wastewater impoundment, tank farm and two compressor stations.
Those surveys detected the main constituents of natural gas—including
methane, ethane, propane and butane—as well as low levels of associated
compounds, including benzene and n-hexane, which were detected
infrequently at the tank farm and at a compressor station. Higher
concentrations of the main constituents of natural gas were detected
mainly near the compressor stations.
Methyl mercaptan, a gas which has a penetrating and unpleasant odor
similar to rotten cabbage or rotten eggs, was also detected at
concentrations that generally produce odors at each location where
samples were taken. That threshold is about one part per billion.
The air sampling surveys conducted for carbon monoxide, nitrogen
dioxide and ozone precursor emissions did not detect levels above
national ambient air quality standards at any of the surveyed sites.
However, DEP has not yet determined if the potential cumulative
emissions of these air contaminants will cause or contribute to
violations of the national ambient air quality standards.
DEP is conducting similar air monitoring studies near Marcellus gas
facilities in the Dimock area of Susquehanna County, as well as in the
north-central region of the state, to determine if there is a
consistent statewide emissions profile for air contaminants near
natural gas operations. All studies are expected to be complete in
January 2011.
Since 2005, 2,300 Marcellus Shale wells have been drilled in
Pennsylvania.
To view the report, visit http://www.depweb.state.pa.us
and click on “Regional Resources,” then on “Southwest Region” and
choose the “Community Information” link on the right side of the page.
URL pasted below should take you directly to
the report. It is in pdf form, and, many pages.
http://files.dep.state.pa.us/RegionalResources/SWRO/SWROPortalFiles/Marcellus_SW_11-01-10.pdf