Rob Brenneman, president of the National Pork Producers Council, which has long pushed for the decision, said in a statement: “This move confirms what farmers have long known: Every farm is different, and there is no one-size-fits-all model to apply to them.”

Heinzen noted that the agency’s decision simply means that this administration has no intention of regulating air emissions from CAFOs, but for now, the Clean Air Act still requires permits for facilities that exceed emissions thresholds. The amnesty granted to these facilities will no longer be in effect now that the agreement has concluded.

“There’s no EPA-issued methodology to estimate emissions,” she said. “That doesn’t mean that there aren’t good studies out there of emissions from different types of animal feeding operations that can be used.”

Heinzen pointed to California, which has models for livestock emissions that it uses to enforce its own air regulations. “We just don’t have one set of national emissions factors from EPA,” Heinzen said.…