The Pennsylvania Department of Environmental Protection has announced that it has finalized certain revisions to a general air permit for natural-gas-fired engines and equipment at compressor stations:  "DEP also announced it will accept public comment on a proposed plan approval and operating permit exemption for air emission sources at well drilling sites. Well sites would only be eligible for the exemption for the air quality plan approval process if the wells will meet emission control and monitoring criteria that are stricter than federal air quality rules for controlling wellhead emissions. The plan approval authorizes construction of facilities that emit certain types and amounts of pollutants."

For more, click on the link above.