Large livestock farms likely will have to report high levels of two types of emissions as of Wednesday, despite the Environmental Protection Agency’s last-minute effort to further delay a federal rule it’s been trying to modify for years.

The EPA tried to exempt most farms, including concentrated animal feeding operations or CAFOs, from having to report emissions of two air pollutants — hydrogen sulfide or ammonia — that are considered hazardous.

Environmental groups, led by Waterkeeper Alliance, objected to the agency’s effort to exempt CAFOs from two laws that date back to the 1980s. The groups said in court documents that ample evidence showed mismanaged manure could lead to toxic releases of the chemicals. A federal appeals court agreed in April and said the rule would go into effect November 15.

But the EPA requested more time to “review and include comments from the public” and “complete the development” of a simpler reporting form, according to agency spokesman Michael Abboud.

“EPA is continuing to work with the U.S. Coast Guard’s National Response Center (NRC) to manage the volume of calls from farmers,” Abboud says in a statement to Harvest Public Media. The NRC is responsible for handling reports of the potential pollutants into the air.

In a statement issued Tuesday, Waterkeeper Alliance says it is the “EPA’s responsibility to protect the public by ensuring information about these releases is disclosed — not to keep devising new legal strategies to help industry keep it secret.”

The appeals court had not ruled on the EPA’s request to delay the rule as of 3 p.m. Wednesday. At least one state agency, North Carolina’s Department of Environmental Quality, emailed various government employees and environmental groups Tuesday with a emissions reporting guidance form. North Carolina is one of the biggest hog producing-states in the U.S.

Erica Hunzinger contributed to this report.

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