The Pennsylvania Department of Environmental Protection (DEP) has finalized its air quality permit criteria, and said it will no longer unconditionally waive operators from the requirement that they submit an air quality plan prior to regulatory approval of unconventional drilling sites.

According to the DEP, the agency may continue to grant operators air quality permit exemptions, but they would need to adhere to a tougher set of standards, even more stringent than rules set by the federal government.

“One of the [new] criteria covers leak detection for the entire well pad site and associated equipment,” DEP spokeswoman Lisa Kasianowitz said Friday. “Previously, just the storage vessels and storage containers were covered, but now it covers leak detection for the entire site, including methane.”

Last February, the DEP reported that despite the Marcellus Shale boom, emissions from natural gas production and processing facilities, including wells and compressor stations, dropped considerably since 2008 (see Shale Daily, Feb. 14).

“Air quality has improved over the past few years, at the same time the state’s energy portfolio continues to expand the development and use of natural gas,” DEP Acting Secretary Chris Abruzzo said. “We fully expect both of those trends to continue, and this strategy builds on existing federal requirements by continuing to set the high, but fair, bar we have come to expect.”

Among the rules finalized by the DEP, any leaks at the entire well pad and facility must be repaired within 15 days, unless the operator shuts the site down or is in the process of acquiring replacement parts. The agency said emissions of volatile organic compounds (VOC) and hazardous air pollutants must also be controlled beyond levels required by the federal rules.

The DEP said emissions of nitrogen oxides (NOx) must be less than 100 pounds per hour, half a ton per day and 6.6 tons per year; federal rules do not address or limit such emissions.

“The final revised guidance affords each operator the choice between seeking an air quality plan approval from DEP, or demonstrating and implementing controls and practices more stringent than the federal rules,” the DEP said.

The state agency also said it would allow open flaring, but only on a short-term or emergency basis. “Flaring used as emission control on storage vessels must be enclosed, resulting in reductions of VOCs and hazardous air pollutants,” the DEP said. “Such enclosed flares have been demonstrated to achieve up to 99.9% elimination of such pollutants.”

Kasianowitz said the DEP received more than 650 public comments on its air quality rules, from February through May 2011, and again from February through March 2013.

The U.S. Environmental Protection Agency (EPA) set national air quality rules for oil and gas wells in April 2012 (see Shale Daily, April 19, 2012). Those include reducing VOCs at wells drilled after Aug. 23, 2011 through a two-phase process requiring flaring followed by “green completions.” The EPA set a deadline of Jan. 1, 2015 for full compliance.