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Throughout the twentieth century we have seen massive changes in industrialization, and technology. The change in this industry has given rise to CAFOs, which are now one of the main producers for meat, poultry and dairy products within the United States.


These large-scale operations have made meat and dairy more financially economical to purchase for the average consumer, but it seems to be at the expense of our environment, and overall health.



EPA Definitions of AFOs and CAFOs: 
"An Animal Feeding Operation (AFO) is a facility in which livestock or poultry are raised or housed in confinement, and where the following conditions are met: (1) animals are confined or maintained for a total of 45 days or more in any 12-month period, and (2) crops are not sustained in the normal growing season over any portion of the lot or facility (i.e., animals are not maintained in a pasture or on rangeland)."
"Concentrated Animal Feeding Operations (CAFOs) are a subset of AFOs. In addition to meeting the above conditions, an AFO is a defined as a CAFO if it meets minimum size thresholds (AFOs with more than 1,000 animals are CAFOs; those with 300-999 animals may be CAFOs, depending on discharge characteristics; and those with fewer than 300 may be CAFOs in some cases) and either one of these conditions: (1) pollutants are discharged into navigable waters through a manmade ditch or similar manmade device, or (2) pollutants are discharged directly into waters of the United States that originate outside of and pass over, across, or through the facility, or otherwise come into direct contact with the confined animals."
The Clean Water Act defined CAFOs as a "point source pollutant." This act states that an EPA or “qualified state” issued permit is necessary for drainage of pollutants from “point sources,” otherwise it is strictly prohibited. Up until 2003, the only regulations for these operations where the guidelines the Clean Water Act had enacted in 1972.
In 2003 there were many long-overdue updates to the past requirements of CAFOs. Waste discharge and permit requirements were among the subject matters that were modified. For the first time it was required that all Condensed Animal Feeding Operations must apply for a permit in order to discharge waste, and secondly to develop/apply a plan for nutrient management. These newly created regulations were a step in the right direction, but the court case, “Waterkeeper Alliance et al. V. EPA,” in 2005 challenged some of these newly required regulations. This resulted in the EPA significantly changing their guidelines, by completely eliminating their “duty to apply” regulation, that required all CAFOs must either prove that they have no potential discharge, or apply for a discharge permit if it is known that the operation will discharge. A part of the 2003 ruling that was maintained was the agricultural storm water discharge exemption. Environmental groups explained that the ruling had left much of the original ruling still in place, yet the EPA chose to dramatically revise their original 2003 rule. 
Something worth noting is that NMPs are not actually enforceable parts of the permit requirement, which was confirmed in the 2008 rule. This rule once again clarified the controversial "duty to apply" rule. Lastly, in 2014 and 2016 there have been vague clarifications that have updated the CWA.

Health Concerns 

Occupational Hazards 

  • Respiratory Problems

  • Asthma

  • Irritation 

  • Headaches 

  • Infectious Agents 

Animal Hazards 

  • Antibiotic Injections

  • Infectious Agents 

  • Living Conditions 

Community Hazards 

  • Odor

  • Headaches 

  • Irritation of Eyes & Nose 

  • Stress

  • Potentially Contaminated Drinking Water


Among the many concerns that CAFOs bring rise to, the environmental implications are the most prominent. This concern stems from CAFOs directly and/or indirectly affecting all three environmental mediums, which are indicated as soil, water, and air.


The waste that is produced is usually handled in a few different ways. It could be spread onto the field as a dry fertilizer, or the waste could be pumped into a man-made ditch/lagoon where waste is held. Several issues arise when the waste produced exceeds the amount they can spread on fields or pumped into lagoons. This can lead to spreading too much onto fields, making bacteria such as E. Coli likely to run off into near by land and water sources.


Another very concerning problem that arises with this waste production is the vast amount of nitrogen and phosphorous it brings into the environment. Nitrogen and phosphorous can be brought into the environment through runoff, ammonia volatilization, and ground water percolation. The excess amounts of Nitrogen and Phosphorous creates excess, dense plant growth, which results in a lack of oxygen. This depletion of oxygen kills wildlife such as fish, which as a result creates dead zones.

Environmental Concerns 

Concentrated Animal Feeding Operations



There are several excellent resources to find out more information regarding CAFOs specific to many areas and communities throughout Wisconsin. Here are a few great resources I have discovered thanks to Frank Koehn, Naomi Tillison, and Mike Wiggins:

Northern Wisconsin Environmental Issues & Politics:

Wisconsin DNR:

Farms Not Factories - Lake Superior:

Ganawenjigaade - Red Cliff Band of Lake Superior Chippewa: (Pages 6 & 7)

WI DNR - Badgerwood - Proposed CAFO  Bayfield, WI:

Nitrates Sources & Concerns:

Contaminated Runoff 

  • Soil Contamination 

  • Water Contamination 

Excess Waste Production

  • Decreased Air Quality

  • Nitrogen & Phosphorous 

  • Excess Plant Growth 

  • Decrease of Oxygen Supply 

  • Dead Zones 

On an occupational level, the CAFO workers are exposed to thousands of animals, which includes their feces, dirt, dust, and particulate matter. The interior air quality of these structures could lead to respiratory problems, asthma, irritation, and headaches. 

Operations this large with thousands of animals are known to have contaminants and bacteria, making it a breeding ground for possible infections. Antibiotics are frequently if not regularly administered to the animals in order to prevent infections, and to ensure the animals will not use their energy fighting off illnesses. This can lead to antimicrobial resistance that is transferable to other animal hosts. These infectious agents can also cause diseases for humans as well. This means that the environment enables mutation of viral pathogens that are undoubtedly transferrable between different species. It has been speculated that H1N1 (Swine Flu) Virus could have originated in a condensed animal feeding operation, because of the close conditions, contaminants, antimicrobial resistance, and infectious agents that can be spread between different species. 

In terms of communities within close vicinity to CAFOs, there are several concerns that arise. These animal operations are known to cause a very prominent odor due to the massive amounts of waste produced by the animals. This odor that is emitted into the air can cause headaches, eye and nasal irritation. There is a significant increase in stress throughout the community, not only due to these pungent odors, but also due to the concerns of water and soil contamination. 


Anchor 1

Townsend, A. R., Howarth, R. W., Bazzaz, F. A., Booth, M. S., Cleveland, C. C., Collinge, S. K., Dobson, A. P., Epstein, P. R., Holland, E. A., Keeney, D. R., Mallin, M. A., Rogers, C. A., Wayne, P. and Wolfe, A. H. (2003), Human health effects of a changing global nitrogen cycle. Frontiers in Ecology and the Environment, 1: 240–246. doi:10.1890/1540-9295(2003)001[0240:HHEOAC]2.0.CO;2

Cole, D., Todd, L., & Wing, S. (2000). Concentrated swine feeding operations and public health: a review of occupational and community health effects. Environmental Health Perspectives, 108(8), 685–699.

Thorne, P. S. (2007). Environmental health impacts of concentrated animal feeding operations: Anticipating hazards-searching for solutions. Environmental Health Perspectives, 115(2), 296-7. Retrieved from

Animal Waste and Water Quality: EPA Regulation of Concentrated Animal Feeding Operations (CAFOs)

Nitrates Sources & Concerns:


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