The Environmental Protection Agency is launching a study on the water quality impacts of large animal feeding operations before deciding whether to tighten rules for them.

In a plan released Friday that addresses several industry sectors, EPA said it needs more information “to identify the extent to which (concentrated animal feeding operations) discharge into ‘waters of the United States.’” The data the agency has is “sparse,” the agency said, noting that “its preliminary analysis was only able to analyze monitoring data from (16) reporting CAFOs.”

A petition filed last fall seeking tougher rules for CAFOs, citing EPA data, said there are about 21,000 large CAFOs in the U.S., but only about 6,000 have Clean Water Act National Pollutant Discharge Elimination Permits.

States largely have responsibility for issuing permits for CAFOs. 

A large CAFO is defined as an operation with more than a certain number of livestock: 1,000 or more cattle or cow/calf pairs, 2,500 swine over 55 pounds (and 10,000 less than that weight), and 700 or more mature dairy cattle, for example.

EPA’s study is in response to a remand from the 9th U.S. Circuit Court of Appeals in a case brought by Food & Water Watch and 11 other groups that challenged the agency's 2019 decision not to revise effluent limitation guidelines for CAFOs. FWW had opposed the voluntary remand, preferring the court decide the case on its merits, but in February 2022 the court allowed EPA to reconsider its decision.

Food and Water Watch Legal Director Tarah Heinzen said Friday the group is “encouraged that EPA acknowledges that it lacks adequate information about this industry and hasn't done a good job of collecting information about the pollution impacts. It's heartening that EPA is going to do a detailed study.”

She added that while there is no guarantee EPA will revise its regulations, her understanding is that a study “is a common first step before EPA would commit to a change in its standards.”

In its plan, EPA said it “has reviewed many studies addressing impacts of CAFOs on surrounding communities and the environment, but little data is available demonstrating the impacts of CAFOs specifically on ‘waters of the United States,’ particularly considering the agricultural stormwater exemption. EPA also intends to assess whether any discharges from CAFOs are concentrated in particular regions or states, or whether they are widespread nationally.”

In addition, "EPA plans to gather information about new technologies and practices for reducing discharges from the production area and land application area. EPA will consider whether these technologies may be technologically available and economically achievable for the CAFOs point source category."

National Cattlemen's Beef Association Chief Counsel Mary-Thomas Hart said "collecting further information will enable EPA to make an informed and reasoned decision on whether to revise the CAFO ELGs. We appreciate that EPA is not choosing to unnecessarily rush its regulatory process.”

The National Pork Producers Council didn't immediately respond to a request for comment. 

A big reason many large CAFOs aren’t permitted is because of the exemption for ag stormwater, which EPA interprets as “any precipitation-related discharges of manure, litter, and process wastewater from the land application areas if the manure, litter, and process wastewater has been applied to the ... area in accordance with a site-specific ‘nutrient management plan’ that ensures appropriate agricultural utilization” of the nutrients in those substances.

“EPA needs to close that loophole,” Food and Water Watch's Heinzen said, noting that FWW and dozens of other groups have petitioned EPA to establish a “rebuttable presumption” that large CAFOs using wet manure systems discharge pollutants and thus should be required to seek permits.

“That will go a long way towards making sure that the whole universe of polluting facilities is regulated as Congress intended under the Clean Water Act,” she said. “EPA itself has estimated that based on how CAFOs are constructed, maintained and operated, approximately 75% of large CAFOs do in fact discharge.”

The plan also launches a study of publicly owned treatment works (POTW) influents “to characterize the PFAS concentrations from industrial dischargers to POTWs and inform implementation of pretreatment programs to address them.”

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