On January 31, the Pennsylvania Department of Environmental
Protection (PADEP) finalized revisions to its "GP-5" air
quality general permit, which include significantly reduced
allowable emission limits. According to PADEP, the revisions to
GP-5 impose emissions limits that are 75 to 90 percent stricter
than current limits for the most common engines used at compressor
stations.
GP-5 authorizes the construction, modification and/or operation
of certain natural gas compression and processing facilities (i.e.,
dehydration, compression, fractionation and storage) that are not
subject to Title V or New Source Review permitting requirements.
Specifically, covered facilities include natural gas-fired spark
ignition combustion engines, simple cycle turbines, centrifugal
compressors, storage vessels, glycol dehydration units,
fractionation process units, equipment leaks, pneumatic controllers
and sweetening units. While the permit covers facilities used on a
gathering line,
