Clean Water Act brings new AFO/CAFO definitions and regulations - April, 2003

Contact: Gene Surber, (406) 994-3414

New rules from the Environmental Protection Agency may affect some Montana livestock operations, says Gene Surber, a natural resources specialist with the Montana State University Extension Service. The EPA recently updated the Clean Water Act with regards to Concentrated Animal Feeding Operations (CAFOs). On Dec. 16, 2002 the new rules were released, which could affect some Montana producers and cow /calf rangeland/pasture operations. State rules will be finalized by April of 2004.

Although the intent of the CAFO rules is not to regulate cow/calf rangeland/pasture operations, the revised act may mean barn lots, pens, corrals, calving lots and winter feeding areas could now be considered Animal Feeding Operations (AFOs) or potential CAFOs.

Among the new rules:

EPA no longer uses animal unit terminology (i.e., one animal unit = a 1,000 pound cow and calf up to four months of age), instead basing regulations on the number of animals (see chart). A cow/calf pair is considered one animal until the calf is weaned, at which time they are considered two animals.

The Mixed Animal calculation was also eliminated. Now, different types of animals are counted separately, rather than adding together the animal unit equivalents, to determine whether the operation is a CAFO. If an operation qualifies as a CAFO for one type of animal, all animals on the operation, and their manure, will be regulated.

The 25-year, 24-hour storm exemption was also eliminated for defining CAFOs. Previously, operations that only discharged as a result of a 25-year, 24-hour flood event did not have to obtain a permit, but now these operations must obtain permits. If these operations comply with their permit, they will avoid liability for discharges in flood events greater than 25-year, 24-hour storm events.

In Montana, a qualifying storm dumps about 2.5 inches of rain in the western part of the state and 3.5 inches in the east.

So how do you determine if your operation an AFO or a CAFO?

"An AFO is defined as an operation where animals are confined for 45 days or more in a 12-month period in an area where there is no vegetation during the normal growing season," said Surber. "The total days do not need to be consecutive, and any number of animals, even one, can place an operation in this category. Animal Feeding Operations are not regulated; CAFOs are."

In winter feeding areas, the “no vegetation” criteria must be evaluated in winter when animals are concentrated, said Tara Fisher, extension natural resources associate in Animal and Range Science Department. "Winter feeding areas used to grow crops or other vegetation during periods when animals are not confined will not exclude them from the AFO definition."

An AFO is considered a CAFO (large, medium or small) based on the number of animals.

Animal Feeding Operations that fall within the "medium" range numbers are only considered a CAFO if they (1) discharge manure or wastewater to surface water through a man-made ditch or pipe, OR (2) surface waters originate outside but pass through the confinement area or come in direct contact with confined animals.

AFOs that fall within the "small CAFO" range are only designated a CAFO if the permitting authority determines that the confinement area is a significant source of water pollution.

Large CAFOs now have a “Duty to Apply” for a National Pollutant Discharge Elimination System (NPDES), which in Montana is a MPDES, permit through the Montana Department of Environmental Quality in Helena. The only exemption is to apply for and demonstrate “No Potential to Discharge,” which requires a 90-day public comment period.

"When determining if the CAFO regulations apply to your operation, keep in mind the number of days, number of animals, and potential to discharge," says Fisher.

For more information, call Gene Surber or Tara Fisher at (406) 994-3414.

This article is excerpted from the March 2003 "Beef: Questions & Answers" newsletter, distributed by the Montana State University Extension Service and Montana Beef Council.

Return to regular view	Text-only	Updated: 08/29/2006