The Pennsylvania Department of Environmental Protection (DEP) has sent a detailed response to Republican state lawmakers that have questioned the necessity of the agency’s plans for a new general permit for unconventional well sites and general permit revisions for natural gas compressor facilities.

Acting DEP Secretary Patrick McDonnell addressed 21 questions submitted by the lawmakers in a letter late last month. He said the goal of the general permits is to decrease confusion over federal emissions requirements, establish best available technology and implement a consistent process to “ensure appropriate controls of emission sources.”

Senate President Joe Scarnati, Senate Majority Leader Jake Corman and Sen. Gene Yaw, chairman of the energy committee, wrote the agency last month to say they fear the proposed permits could jeopardize the industry’s competitiveness.

In their letter, they sent a series of questions asking what justifies the permits and what cost-benefit analysis has been conducted among other things. The letter followed another from Republican state Rep. Daryl Metcalfe that accused the agency of skirting the state’s Regulatory Review Act in opening the draft permits for public comment. Metcalfe received a response from DEP as well.

The permits, McDonnell said, are authorized by both federal and state law. He noted that neither of them propose new regulations, but would implement existing regulatory authority. “The DEP regulates methane under existing statutory and regulatory authority,” McDonnell wrote. “[The U.S. Environmental Protection Agency] developed several regulations that apply to sources at unconventional natural gas well site operations, natural gas compression stations, processing plants and transmission stations. Some of these regulations require the control of methane emissions from these sources.”

The DEP unveiled its proposals late last year and opened them to public comment on Feb. 4. The new general permit for unconventional well sites (GP-5A) and revisions for the general permit for compressor stations (GP-5) are part of Gov. Tom Wolf’s plans to reduce oil and gas industry emissions. The proposals would also affect remote pigging stations, transmission stations and processing plants.

As part of the methane reduction strategy, McDonnell said the agency looked at a wide variety of emission sources and found that the gas industry is the largest source in the state, noting that all others have been flat or down since the 1990s. The DEP, he said, used an economic impact analysis developed by the EPA and another developed internally.

The new permit for unconventional well sites would replace the Category No. 38 conditional permit exemption for oil and gas exploration, which changed DEP’s air permitting policy and allowed regulators to more narrowly identify sources or categories of sources that could be exempt from plan approval. But McDonnell said the conditions for eligibility under exemption 38 are numerous and have likely led to confusion over compliance. The DEP, McDonnell wrote, has discovered a high noncompliance rate among operators with this provisions, saying that since 2013 over 3,000 wells have been drilled and there is a 28% noncompliance rate with exemption 38.

He also noted that other states, including Alaska, Louisiana, Texas, Ohio, West Virginia and Colorado have developed general permits for the industry. Ohio finalized and began accepting applications for general permits for natural gas compressor stations last week.

Like those, DEP’s proposals would establish best available technology for leak detection and repair, recordkeeping and reporting requirements, among other things. The Republican leadership had asked the DEP to extend its public comment period. When it opened last month, the period was supposed to close on March 22, but has since been extended to June 5.

“I would like to stress that these are draft proposals,” McDonnell said in his letter to the Senate leaders. “Despite meeting with 22 stakeholders in 27 meetings over an 11-month period, the DEP recognizes that there are still valuable opportunities to learn more through the formal public comment process.”