A U.S. District Court this week dismissed a lawsuit brought by the Humane Society of the United States and other activist groups against the U.S. Environmental Protection Agency, alleging the agency would not regulate confined animal feeding operations. The groups requested in 2009 that the EPA begin rulemaking under the Clean Air Act to regulate air emissions from CAFOs.

The U.S. District Court for the District of Columbia Circuit threw out the case because the plaintiffs didn’t give EPA 180-days’ notice of their intent to sue, which is required by the CAA. In 2006, nearly 1,900 pork producers and other livestock and poultry farmers entered into a series of legally binding consent agreements with the EPA, settling what the agency believed were issues with air emissions associated with livestock production.

Part of the agreements was a study of emissions from farms. Purdue University conducted the study and gave the data to EPA, which has been reviewing it and working to develop a tool producers can use to estimate air emissions. That process was impeded by the same activist groups that brought the lawsuit when they opposed efforts by the livestock industry to help set up a science advisory panel of experts in animal systems to assist with the EPA’s effort. The agency’s existing science advisory board issued findings on the emissions data in 2013, saying they were “unreliable.”

HSUS indicated it would refile the lawsuit after providing the 180 days’ notice.