State [PA] Tightens Rules for Drilling Engines
2 February 2013
By Don Hopey
The state Department of Environmental Protection said newly
updated requirements for natural gas-powered engines used at
Marcellus Shale gas compressor stations tighten existing emissions
standards by 75 to 90 percent.
But the changes only confirm existing industry emissions
technology, according to environmentalists, and could allow air
quality to worsen because emissions of pollutants from individual
wells wouldn't be aggregated.
The new compressor station engine emissions standards for nitrogen
oxides, volatile organic compounds, formaldehyde and carbon are
part of an updated but narrower DEP General Permit-5, or GP-5,
published in Friday's Pennsylvania Bulletin.
The DEP is proposing that those wellhead and impoundment
operations be exempted from requirements to get a plan approval
and operating permit if they meet emissions limits and monitoring
criteria stricter than federal standards.
DEP Secretary Michael Krancer said in a department news release
the new approach to controlling gas well drilling, storage tank
and compressor station emissions will result in pollution
But the general permit only confirms existing industry practices,
said David Presley, an attorney with the Clean Air Council, one of
eight environmental and community groups to raise concerns about
the permit revision.
"The new GP-5 definitely ratchets down emissions, but only from
the limits contained in the general permit language form 2006,"
Mr. Presley said. "They actually match what the industry has been
doing for the past two years."
Mr. Presley said DEP also did not address concerns expressed by
the U.S. Environmental Protection Agency that the state's failure
to control the aggregated emissions from the state's Marcellus
Shale developments could cause a decline in air quality.
There are more than 400 compressor stations operating in the
state. Residents living near some of those stations have
complained about emissions and air quality, and the Clean Air
Council this week reported that the levels of nitrogen oxides in
the air near one of those, in Lycoming County, was nearly three
times higher than the national ambient air quality standard.
Nitrogen oxides contribute to the creation of unhealthy
ground-level ozone, smog and acid rain.
Mr. Presley also questioned whether Marcellus Shale well pad
operations are insignificant enough emitters of pollutants to
qualify as an "exemption."
A recent "industry study out of New York state found wells can
emit up to 20 tons of volatile organic compounds a year. That
doesn't sound like an insignificant source," he said. "Exemptions
can be granted to anything DEP deems an insignificant source, but
we think the authority is shaky on this. It's something we're
The final general permit document and proposed exemptions
document, plus more information, are available at
www.dep.state.pa.us (click "Air" then "Bureau of Air Quality") or
The DEP will accept comments on the proposed exemptions until
March 19. Written comments, suggestions or objections to the
wellhead and impoundment exemptions should be submitted to
Krishnan Ramamurthy, environmental program manager, Division of
Permits, Bureau of Air Quality, 12th Floor, Rachel Carson State
Office Building, P.O. Box 8468, Harrisburg, PA 17105-8468; or at