A Compendium of Regulated Concentrated Animal Feeding Operation (CAFO) Manure Land Application Regulations Produced by the Sustainable Phosphorus Alliance Authors: Eleanor Rauh, Matthew Scholz, Rebecca Muenich Published April 3, 2019 Based on data compiled March 20, 2019 NOTE: Regulations are “living” data in that they are always being updated. While we will do our best to update the database when we have resources available, some data may not be up-to-date. Additionally, as we improve the quality assurance of the existing data, the compendium may be updated. Preface Applying animal wastes (manures) as an organic form of fertilizer is not a new concept. However, currently, the use of manures in U.S. agriculture has been focused primarily as a way to deal with excess manure generated from large-scale animal production, rather than as a viable, alternative nutrient source to energy-intensive, but cheap, inorganic fertilizer options. While most animal manure produced in the U.S. is land applied for agricultural purposes, much of the applications are not subject to regulation, and there are many cases of over-application of these rich nutrient sources. Manures, which in this report can also mean litter, process wastewater, and other solid or liquid by-products of animal agriculture production, can provide phosphorus and nitrogen, in addition to organic matter, all of which can be beneficial for soil health and agricultural productivity. However, existing federal regulations governing the land application of manures from regulated farms, called concentrated animal feeding operations (CAFOs), allow for substantial flexibility in state interpretation of which farms are regulated how. The U.S. Environmental Protection Agency defines animal feeding operations (AFOs) as agricultural operations where animals are kept and raised in confined situations. Specifically, an AFO has animals that have been, are, or will be stabled or confined and fed or maintained for a total of 45 days or more in any 12-month period, and where the operation does not have crops, vegetation, forage growth, or post-harvest residues sustained during normal growing season over any portion of the lot or facility. If an AFO meets animal number specifications set in Table 1, then these are considered CAFOs and may then be subject to NPDES permitting, depending on the state. Table 1. CAFO size categories from 40 CFR. Animal type Sizes Defined by Animal Numbers Large CAFO Medium CAFO Small CAFO Cattle or cow/calf pairs > 1000 300-999 < 300 Mature dairy cattle > 700 200-699 < 200 Veal calves > 1000 300 – 999 < 300 Swine (weighing over 55 pounds) > 2500 750 – 2499 < 750 Swine (weighing less than 55 pounds) > 10000 3000 – 9999 < 3000 Horses > 500 150 – 499 < 150 Sheep or lambs > 10000 3000 – 9999 < 3000 Turkeys > 55000 16500 – 54999 < 16500 Laying hens or broilers (liquid manure handling systems) > 30000 9000 – 29999 < 9000 Chickens other than laying hens (other than a liquid manure handling systems) > 125000 37500 – 124999 < 37500 Laying hens (other than a liquid manure handling systems) > 82000 25000 – 81999 < 25000 Ducks (other than a liquid manure handling systems) > 30000 10,000 – 29999 < 10000 Even in this base definition, there are variations by state. Not every state requires all CAFOs to have a National Pollutant Discharge Elimination (NPDES) permit. Some states require all CAFOs to have an NPDES permit while others only require an NPDES permit if the CAFO has actual discharges to waters of the U.S. Additionally, the animal type categories and numbers may vary by state. For instance, Wyoming has a “buffalo” animal type category. The federal regulations require that CAFOs with NPDES permits submit a nutrient management plan (NMP) in an effort to better manage the runoff occurring from the land application of CAFO manures. The federal regulations set minimum standards for what should be required in the NMP, but specific rules are left up to the states. Many states choose to follow explicitly or implicitly the Natural Resource Conservation Service Conservation Practice Standard for Nutrient Management (Code 590). Other states adopt additional practices based on state extension guidance.