Meyer and others said that since 2011 under Gov. Scott Walker and DNR Secretary Cathy Stepp, the agency has shifted emphasis toward quickly providing emission permits to businesses and away from enforcement against polluters and scientific study of emerging problems.

The DNR has maintained that it continues to do research and that staffing shortages have slowed enforcement.

A spokeswoman for the air program in the EPA’s Chicago office said it is relatively common for the agency to issue findings of failure to states.

“EPA’s action only pertains to a small part of the (Wisconsin) state-run permitting program,” spokeswoman Phillippa Cannon said in an email response to questions from the State Journal.

“Wisconsin’s plan to implement the Clean Air Act did not include one element — the state did not set the amount of fine particles that facilities can emit over the amount allowed in a given area,” Cannon said.

The limits are designed to prevent significant degradation of air quality in areas that don’t have serious pollution problems.