By Adam Lidgett

The Environmental Protection Agency on Friday filed a notice with the Federal Register saying it has reached an agreement to settle a suit filed by environmental groups accusing the agency of failing to update its air quality standards for sulfur oxide and oxides of nitrogen every five years.

The Center for Biological Diversity and the Center for Environmental Health filed their complaint against the EPA in July, and have alleged the Clean Air Act requires the EPA to update its air quality standards for sulfur oxide and oxides of nitrogen every five years, and that the EPA missed its 2015 deadlines to review the pollutants. The EPA filed in a notice of a proposed consent decree in the suit on the Federal Register, allowing public comments to be received on the proposed deal.

“The proposed consent decree would establish deadlines for EPA to take certain, specified actions in the periodic reviews, and if appropriate, revisions of the air quality criteria addressing human health effects of sulfur oxides and the primary National Ambient Air Quality Standards for oxides of nitrogen and sulfur oxides,” the EPA said.

Under the terms of the proposed consent decree, the EPA would sign a notice setting forth a proposed decision on its review of the primary NAAQS for oxides of nitrogen no later than July 14, 2017, and sign a notice setting forth a final decision regarding the review of that primary standard no later than April 6, 2018. The proposed consent decree would require the EPA to sign a notice setting forth its proposed decision concerning the review of the primary standard for sulfur oxide no later than May 25, 2018, and sign a notice putting forth its final decision regarding the review of that standard no later than Jan. 28, 2019.

The proposed deal, lodged on Jan. 6, isn’t final and can’t be entered by the court until the EPA administrator provides a reasonable opportunity through a notice on the Federal Register for people who aren’t parties to the lawsuit to comment on the proposed consent decree, the parties said in a filing with the court Thursday.

The environmental groups had argued that there is research now that wasn’t around during the last EPA pollution update in 2010 that more strongly links sulfur and nitrogen oxides with health risks.

“The Clean Air Act has proven to be our best tool to save millions of lives and protect the environment from the dangers of acid rain and haze, but it only works when it is enforced,” Jonathan Carter Evans, an attorney for the environmental groups, said in a statement. “We can’t trust the polluters to police themselves, and we need the strong blueprint of clean air standards to force polluters to clean up their act.”

Caroline Cox, research director at the Center for Environmental Health, further said that the CAA has been a very powerful tool for ensuring clean air.

“The important thing is to keep the Clean Air Act a really good tool for making sure we all breathe healthy air, and that’s what this lawsuit was about,” she told Law360.

Representatives for the EPA did not immediately respond to requests for comment Friday.

The environmental groups are represented by Center for Biological Diversity staff attorney Jonathan Carter Evans and Robert Ukeiley of the Law Office of Robert Ukeiley.

The EPA is represented by John C. Cruden and Leslie M. Hill of the U.S. Department of Justice.

The case is Center for Biological Diversity et al. v. McCarthy, case number 3:16-cv-03796, in the U.S. District Court for the Northern District of California.

–Editing by Philip Shea.