Animal Feeding Operations



Animal feeding operations (AFOs) are agricultural entities that raise animals in confined areas. More specifically, AFOs are defined in the regulations implementing the Clean Water Act (CWA) as facilities, except aquatic animal production facilities, that confine and feed animals for 45 or more days per year and do not have sustained vegetation during the growing season over any portion of the facility. This overview focuses on environmental regulation and common law actions as they pertain to animal feeding operations. Read the full overview


Note: Recently added resources are posted at the top of the applicable sections.

Major Statutes

Agricultural Improvement Act of 2018

Federal Water Pollution Control Act (aka Clean Water Act) 33 U.S.C. §§ 1251-1388

Federal Air Pollution and Control Act (aka Clean Air Act), 42 U.S.C. §§ 7401-7671q

Comprehensive Environmental Response, Compensation, and Liability Act 42 U.S.C. §§ 9601-9675

Emergency Planning and Community Right-to-Know Act 42 U.S.C. §§ 11001-11050

Compilation of States’ Farm Animal Confinement Statutes

Compilation of States’ Right-To-Farm Statutes


Packers and Stockyards Act

CAFO Regulations

EPA Animal Feeding Operation Clean Water Act Regulations
40 C.F.R. pts. 122
40 C.F.R. pts. 123
40 C.F.R. §§ 412.1-412.47

EPA Clean Air Act State Implementation Plan Regulations

40 C.F.R. Part 52 Vol. 3 (Alabama through Louisiana)

40 C.F.R. Part 52 Vol. 4 (Maine through Oregon)

40 C.F.R. Part 52 Vol. 5 (Pennsylvania through Wyoming includes U.S. Territories)

EPA Clean Air Act State Operating Permit Regulations, 40 C.F.R. Part 70

EPA Clean Air Act Federal Operating Permit Regulations, 40 C.F.R. Part 71

EPA Comprehensive Environmental Response, Compensation, and Liability Act Reporting Regulations, 40 C.F.R. §§ 302.1-302.8

Emergency Planning and Community Right-to-Know Act Notification Regulations, 40 C.F.R. Part 355

Federal Register Rules Open for Comment

Case Law

Case Law Index for Animal Feeding Operations

Administrative Law Decisions

EPA Office of Administrative Law Judges

Environmental Appeals Board

Center published USDA Judicial Officer’s Decisions

Center Research Publications

Issue Brief: Organization for Competitive Markets Seeks Judicial Review of USDA’s GIPSA Rule Withdrawal (Lizano, E. Rumley, 2018)

Issue Brief: Smithfield Foods and Right to Farm in North Carolina (Rumley, 2018)

Issue Brief: Petition for Policy Change in FSIS’ “Product of U.S.A.” Label (Lizano, Rumley, 2018)

Cattle Traceability: Potential Legal Implications (Rumley & Dowell)

The Veterinary Feed Directive Rules for Veterinarians: A Practical Guide for the Practicing Veterinarian  (Roasa, 2016)

Legal Issues in Animal Agriculture: Medication, Identification and Accommodations (E. Rumley)

States’ Farm Animal Confinement Statutes (E. Rumley, 2009)

The Clean Water Authority Restoration Act: A Primer of Background Material (Goeringer & Rumley, 2009)

States’ Right-To-Farm Statutes (NALC Staff, 2009)

Environmental Law: Federal Laws That Affect Agriculture – PowerPoint Presentation (Springsteen, 2009)

Governments and Unconstitutional Takings: When Do Right-To-Farm Laws Go Too Far? (Centner, 2007)

Clarifying NPDES Requirements for Concentrated Animal Feeding Operations (Centner, 2007)

2005 Environmental Law Update (Feitshans, 2006)

Market Concentration, Horizontal Consolidation, and Vertical Integration in the Hog and Cattle Industries: Taking Stock of the Road Ahead (Pittman, 2005)

Legal Issues in Developing a National Plan for Animal Identification (Roberts and Pittman, 2004)

Nuisance Immunity Provided by Iowa’s Right-To-Farm Statute (Dzur, 2004)

Government Oversight of Animal Feeding Operations (Centner, 2003)

Congressional Research Service Reports

Reports– published and made available by CRS beginning in 2017

Subjects– published by CRS and made available by NALC until 2018:

Animal Agriculture
Climate Change
Environmental Issues

Agricultural Law Bibliography

Introduction   |   Keyword Search   |   Browse Categories

Legal publications on Animal Feeding Operations:

Agribusiness Corporations
Animals – Animal Rights
Corporate Farming (Restrictions on Corporate Farming/Family Farm Preservation)
Environmental Issues
Farm Labor
Farmer-Processor Bargaining – Production Contracts
Land Use Regulation
Livestock and Packers & Stockyards
Veterinary Law

Reference Resources

Agricultural Research Service (ARS)

National Research Program: Animal Production and Protection
National Research Program: Natural Resources and Sustainable Agricultural Systems
Publication: Agricultural Phosphorus and Eutrophication (2003)
News & Events: Avian Influenza

Animal and Plant Health Inspection Service (APHIS)

National Animal Identification System
Publications: Animal Health

Economic Research Service (ERS)

Animal Products
Manure Management
Farm Structure and Organization
Animal Policy and Regulatory Issues
Cattle and Beef
Hogs and Pork
Poultry and Eggs

ERS Recommended Readings:

Agricultural Contracting Update: Contracts in 2003 (2006)
Managing Manure to Improve Air and Water Quality (2005)
Improving Air and Water Quality Can Be Two Sides of the Same Coin (2005)
Structural Change in the Meat, Poultry, Dairy, and Grain Processing Industries (2005)
Manure Management for Water Quality (2003)
Economic and Structural Relationships in U.S. Hog Production (2003)
Manure Management for Water Quality: Costs to Animal Feeding Operations of Applying Animal Manure Nutrients to Land (2003)
The Changing Landscape of U.S. Milk Production (2002)
Confined Animal Production and Manure Nutrients (2001)
Change in U.S. Livestock Production, 1969-92 (1997)

Environmental Protection Agency (EPA)

Inspections of Concentrated Animal Feeding Operations
National Agricultural Compliance Assistance Center (NACAC)
National Pollution Discharge Elimination System (NPDES) Permit around the Nation
Air Monitoring at Agricultural Operations
Unified National Strategy for Animal Feeding Operations (EPA/USDA)
EPA Topic: Water
Managing Manure Nutrients at CAFOs 
Clean Water Act Information
Clean Air Act Information
Comprehensive Environmental Response, Compensation, and Liability Act Information
Resource Conservation and Recovery Act Information

National Institute of Food and Agriculture (NIFA)

National Emphasis Area: Animals
Topics: Environment
Programs: Manure & Nutrient Management

Natural Resources Conservation Service

Technical Resources: Animal Feeding Operations
Technical Resources: Manure and Nutrient Management
Unified National Strategy for Animal Feeding Operations Cost Assessment
Agricultural Air Quality Task Force

Congressional Resources

U.S. Senate Agriculture, Nutrition, and Forestry Committee

U.S. Senate Committee on Environment and Public Works

U.S. House Committee on Agriculture

U.S. House Committee on Agriculture Reports on AFOs (House Bill Report No. ESSB 5889)(Government Accountability Office)

Climate Change Science: High Quality Greenhouse Gas Emissions Data are a Cornerstone of Programs to Address Climate Change (GAO-09-423T)

CAFOs: EPA Needs More Information and a Clearly Defined Strategy to Protect Air and Water Quality from Pollutants of Concern (GAO-08-944)

Other Federal Resources

National Center for Environmental Health: Concentrated Animal Feeding Operations (Centers for Disease Control)

Animal Feeding Operations: Effects on Hydrologic Resources and the Environment (U.S. Geological Survey)

Toxic Substances Hydrology Program: Animal Feeding Operations (U.S. Geological Survey)

Grain Inspection, Packers and Stockyards Administration Assessments of the Cattle and Hog Industries (National Agricultural Library)

National Agricultural Statistics Service


Manure Management for Climate Change Mitigation: Regulating CAFO Greenhouse Gas Emissions Under the Clean Air Act (Tomas, 2019)

Recordkeeping & Inspections for Animal Feeding Operations (MT State U. Ext. 2017)

Economic Analysis Impact (Dept. of Ecology State of Washington, 2016)

The Association between Proximity to Animal Feeding Operations and Community Health: A Systematic Review (O’Connor, 2010)

Manure Management Plan – A Step by Step Guide for Minnesota Feedlot Operators (U. of MN, Ext., 2010)

Impacts of Waste from Concentrated Animal Feeding Operations in Water Quality (Burkholder, et al. 2006)

Ohio Livestock Manure Management Guide (OH St, Ext., 2006)

Iowa Concentrated Animal Feeding Operation Air Quality Study (U. of IA, 2003)

Air Emissions From Animal Feeding Operations: Current Knowledge, Future Needs (National Academies Press, 2003)

Additional Resources

Animal Feeding Operations Posts (Ag & Food Law Blog)

State Regulation of Animal Feeding Operations: Seven State Summaries

Concentrated Animal Feeding Operations (Nat’l Conf. of State Legislatures)

Environment, Energy, and Resources Section (American Bar Association)

Iowa Department of Natural Resources: Animal Feeding Operations

Nutrient Management Planning with Animal Feeding Operations (Alabama Cooperative Extension Service)