The Humane Society of the United States served 51 hog facilities with notice of intent to sue Wednesday, citing findings from their own research that point to ammonia releases that have gone unreported to the EPA.
Facilities cited are located in Iowa, North Carolina and Oklahoma.
According to an HSUS statement, law requires all facilities that release certain amounts of harmful contaminants to report those amounts to state and local emergency response teams and the EPA. HSUS said that the facilities in question did not report ammonia releases that exceeded 100 pounds in a 24 hour period.
But, the NPPC said those limits don't exist.
"There are no air emissions standards for livestock and poultry operations," said Dave Warner, a spokesman for the National Pork Producers Council. "We agreed with EPA that if you are going to set the standards, do it based on science."
Warner said the NPPC is actively working with the EPA to complete a two-year study conducted by Purdue University that examines emissions from hog and poultry operations. That study, which may soon become the basis for EPA emissions standards, is at least a year away from completion, Warner said.
But, the NPPC said HSUS's "intent to sue" isn't about how much ammonia there is, but whether the facilities are correctly reporting to the EPA.
The reporting rule in question went into effect in 2009, but the EPA created "widespread confusion" about it, with some states refusing to accept the reports and others telling farmers the reporting requirement was a hoax, Warner said.
"EPA did a poor job of telling producers about this and educating them about this and about how to determine if they meet a threshold that would require them to report," Warner said.
And, he said, just because ammonia levels have to be reported when they are over a certain level doesn't necessarily mean they are dangerous.
But, HSUS thinks otherwise. HSUS spokesman Jonathan Lovvorn said the facilities are "a menace to the environment, to the community, and to the animals."
The notice letters sent Wednesday were required under the federal Emergency Planning and Community Right-to-Know Act before litigation can start, according to that statute's citizen suit provisions, HSUS said.
Warner said that HSUS is simply using those letters as a scare tactic to attack NPPC's opposition to the HSUS egg bill and the group's false claims about gestation crates.
"When it comes to all types of environmental issues, whether it's land, water, or air, the U.S. pork industry has been very progressive," Warner said. The HSUS "isn't telling the truth about how hog farmers raise and care for their animals and now it's not telling the truth about hog farmers' stewardship of the environment."