The order applies only to enforcement actions in the Marcellus Shale, the gas-rich formation that has drawn a flood of drilling companies to northern and western Pennsylvania.
According to Hanger, there has never been a similar directive in DEP.
John Hines, the DEP executive deputy secretary, sent an e-mail March 23 to other senior staff, including four regional directors and the head of the department's oil and gas division.
"Effective immediately," it said, all violations must first be sent to him and another DEP deputy secretary in Harrisburg - with "final clearance" from Michael Krancer, DEP secretary.
"Any waiver from this directive will not be acceptable," Hines wrote. Regional directors reinforced the stern message in their own e-mails to staff.
Formal notices of violation, or NOV's in DEP parlance, are the inspectors' main tool in enforcing compliance with environmental rules. Drilling companies have to meet a host of standards for operating their wells, managing erosion, preventing spills, and disposing of the polluted wastewater left over from the process used to extract the gas, known as fracking.
For decades, DEP inspectors in the field have had the authority to write violations on their own. Companies may appeal if they disagree with the findings.
A DEP spokeswoman said the policy was designed to make sure that all natural gas firms, regardless of where they were drilling, were treated the same by regulators.
"It is a response to the many complaints the secretary has received from legislators and constituents," said spokeswoman Katy Gresh. "They believe DEP is inconsistent, particularly when it comes to Marcellus Shale."
She also said that Corbett's office did not order the policy shift, and that it did not mean the department was buckling to pressure from industry.
"This is not political," she said.
Drilling companies have long been complaining that they often face different standards from inspectors in different DEP regions.
"We've talked about the need to have clarity," said Kathryn Z. Klaber, president of the Marcellus Shale Coalition, an industry group. "It's not about cutting corners. It's about getting to compliance more quickly by understanding the requirements."
The agency did not announce the new policy. Gresh called it an "internal" directive. The e-mail was obtained this week by The Inquirer and other news organizations.
Hanger said the "extraordinary" policy was akin to forcing a highway trooper to get approval from the head of the state police before writing a ticket.
"It is a complete intrusion into the independence of the inspection process," he said. He said Krancer should rethink the order.
Critics also fear that the directive will delay and chill enforcement by requiring all violations to be funneled through top officials in Harrisburg. Inspectors issued more than 750 violations in the Marcellus last year alone, according to DEP data.
"Why would I deal with the ticky-tacky local DEP guy who wrote the notice of violation?" said David Masur, director of PennEnvironment. "I'll just go to his boss and tell him to call off the dogs."
One DEP field inspector said the order was first greeted with disbelief, then anger.
"They are putting us on a leash," said the inspector, who spoke on condition of anonymity because of a fear of retaliation.
Inspectors worry that the new order amounts to a "backdoor way to castrate the regulations."
The inspector also said that while companies frequently complain about inconsistent enforcement, supervisors have not brought up the topic.
"Not a single person in my office believes this is about ensuring uniformity," the inspector said.
Corbett, who received more than $800,000 in campaign contributions from drilling interests last year, has taken several actions to help the industry since taking office in January.
His administration overturned a moratorium on drilling in state forests, and Corbett has announced that he will not consider any extraction tax on drillers. Pennsylvania is the only major natural gas-producing state without such a tax.
Josh Kratka, senior attorney with the National Environmental Law Center in Boston, said it was disturbing that Krancer had created a separate set of rules for Marcellus drillers.
"It's troubling for me to hear the top official of an an environmental agency carving out an industry for special treatment," Kratka said.
Gresh, the DEP spokeswoman, said the agency singled out Marcellus Shale enforcement because that's the industry that has generated the most activity - and the most complaints about differing standards.
"Secretary Krancer wanted to start somewhere," she said.
Contact staff writer Joseph Tanfani at 215-854-2684 or firstname.lastname@example.org.