Haze and smog shroud the mountain view behind the Denver City and County Building, as seen in a Nov. 5, 2019, file photo. (John Ingold, The Colorado Sun)

Colorado’s attorney general has appointed four special investigators to look into whistleblower allegations that dozens of air pollution permits were issued unlawfully to companies by a state health department pollution control unit and that at least one whistleblower was asked to falsify data to get pollution estimates under permitted limits.

Attorney General Phil Weiser issued a Thursday statement saying his office had appointed attorneys at Troutman Pepper Hamilton Sanders LLP, an Atlanta-based firm, as special assistant attorneys general to conduct the independent investigation.

As reported by The Colorado Sun, staff at the health department’s Air Pollution Control Division alleged in a complaint that health department division leaders ignored U.S. Environmental Protection Agency regulations on permitting short-term pollutants from important Colorado industries — including mines, asphalt plants and oil and gas gathering sites.

Their complaint was filed with the EPA’s office of inspector general on March 30.

Jill Hunsaker Ryan, executive director of the Department of Public Health and Environment, asked for the investigation. Independent investigators are needed because the attorney general could represent the health department and the state in any future action.

The department has said the division followed state and federal laws but would be transparent throughout the process.