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Animal Feeding Operations - Best Management Practices (BMPs)

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Animal Feeding Operations Highlights

Operating procedures, schedules of activities, maintenance procedures, and other management practices that animal feeding operations can use to prevent or reduce pollution.

Related topics
Homeland Security for Agriculture

More information from the states
Montana State University: Environmental Self-Assessment for Beef Operations (PDF) (34 pp, 233K)

Managing Nonpoint Source Pollution in Coastal Waters

EPA specifies management measures to protect coastal waters from agricultural animal sources of non-point pollution.

Management measures: "Management measures" are defined in section 6217 of the Coastal Zone Act Reauthorization Amendments of 1990 (CZARA) as economically achievable measures to control the addition of pollutants to our coastal waters, which reflect the greatest degree of pollutant reduction achievable through the application of the best available non-point pollution control practices, technologies, processes, sifting criteria, operating methods or other alternatives.

These management measures will be incorporated by states into their coastal non-point programs, which under CZARA are to provide for the implementation of management measures that are "in conformity" with this guidance.  Under CZARA, states are subject to requirements as they develop and implement their Coastal Non-point Pollution Control Programs, and will have some flexibility as they conform with this guidance.

Management practices: In addition to specifying management measures, EPA also lists and describes management practices for illustrative purposes only.  While state programs are required to specify management measures in conformity with this guidance, state programs need not specify or require implementation of the particular management practices described by EPA.  However, as a practical matter, EPA anticipates that the management measures will be implemented by applying one or more management practices appropriate to the site, location, type of operation, and climate. The practices have been found by EPA to be representative of the types of practices that can be applied successfully to achieve the management measures. EPA has also used some of these practices, or appropriate combinations of these practices, as a basis for estimating the effectiveness, costs, and economic impacts of achieving the management measures.

Agriculture Nonpoint Source Pollutants: The primary agricultural non-point source pollutants are nutrients (particularly nitrogen and phosphorus), sediment, animal wastes, pesticides, and salts. Agricultural non-point sources enter surface water through direct surface runoff or through seepage to ground water that discharges to a surface water outlet. Various farming activities result in the erosion of soil particles. The sediment produced by erosion can damage fish habitat and wetlands and often transports excess agricultural chemicals resulting in contaminated runoff. This runoff affects aquatic habitat by increasing temperature and decreasing oxygen.

More information from EPA
Guidance Specifying Management Measures for Sources of Non-Point Pollution in Coastal Water
Agriculture Chapter Fact Sheet
Chapters Related to Confined Agricultural Animals - Management Measure for Facility Wastewater and Runoff from Confined Animal Facility Management (Small Units)
Coastal Non-Point Source Pollution Control Program
Fact Sheet: Protecting Coastal Waters from Nonpoint Source Pollution
Best Nonpoint Source Documents - Agriculture, January 2001

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Ruminant livestock such as cattle and sheep are the largest source of methane emissions resulting from human activity. Scientists estimate that global ruminant livestock industries produce about 20 percent of the world's methane emissions associated with human activity. Methane, produced as part of the animals' normal digestive process, is a potent greenhouse gas that contributes to global climate change. By improving livestock production efficiency, producers can both increase profits and reduce methane emissions.

One method of reducing methane emissions from livestock is to supplement the animal's diet.  Scientists have found that supplementing a cow's diet with substances such as urea increase the animal's ability to digest food.  With improved digestion, less fermentation takes place during digestion, and methane emissions per unit of forage have been reduced 25-75 percent.  In addition, as digestion improves, productivity also improves, as dairy cows produce more milk and beef cattle fatten faster.

The Methane to Markets Partnership is an action-oriented initiative that will reduce global methane emissions to enhance economic growth, promote energy security, improve the environment, and reduce greenhouse gases. Other benefits include improving mine safety, reducing waste, and improving local air quality. The initiative focuses on cost-effective, near-term methane recovery and use as a clean energy source. It will be done internationally through collaboration between developed countries, developing countries, and countries with economies in transition — together with strong participation from the private sector. The Methane to Markets Partnership initially targets three major methane sources: landfills, underground coal mines, and natural gas and oil systems.

Related publications from the Ag Center
Sector Notebooks - Industry Sector Profiles

More information from EPA
Climate Change

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AgSTAR Program

The AgSTAR Program is a voluntary program jointly sponsored by EPA, USDA, and the U.S. Department of Energy. The program encourages the use of methane recovery (biogas) technologies at concentrated animal feeding operations (CAFOs) that manage manure as liquids or slurries to reduce greenhouse gas (methane) while achieving other environmental benefits including odor control and nutrient management opportunities. 

The AgSTAR Program provides important tools, guidance, and methods that allow participating livestock producers to comprehensively assess the applicability of various biogas systems for their livestock production facility.  Utilizing these services provides producers with the information needed to make "go" or "no go" business and environmental decisions based on technology choice, operational ability, and financial performance.

More information from EPA
The AgSTAR Program
AgSTAR Tools
AgSTAR Library
AgSTAR Handbook
FarmWare Software
FarmWare is an analytical tool designed to provide a preliminary assessment on the feasibility of integrating anaerobic digestion into an existing or planned manure management system. The new version contains updated computations for biogas generation and costs of digester systems. AgSTAR Hotline:  1-800-95-AgSTAR (1-800-952-4782)

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The Ruminant Livestock Efficiency Program

Ruminant animals, such as cattle, sheep, buffalo, and goats, are unique. Because of their special digestive systems, they can convert otherwise unusable plant materials into nutritious food and fiber. This same helpful digestive system, however, produces methane, a potent greenhouse gas that can contribute to global climate change. Livestock production systems can also emit other greenhouse gases such as nitrous oxide and carbon dioxide.

Globally, ruminant livestock produce about 80 million tons of methane annually, accounting for about 22% of global methane emissions from human-related activities. An adult cow may be a very small source by itself, emitting only 80-120 kgs of methane, but with about 100 million cattle in the U.S. and 1.2 billion large ruminants in the world, ruminants are one of the largest methane sources. In the U.S., cattle emit about 6 million metric tons of methane per year into the atmosphere, which is equivalent to about 36 million metric tons of carbon.

More information from EPA
The Ruminant Livestock Efficiency Program
Frequently Asked Questions: Ruminant Livestock Efficiency
Resources and Tools: Ruminant Livestock Efficiency

Publications and Software from EPA
Livestock Analysis Model (LAM) Software
Small Steps Make A Difference Booklet (PDF) (16 pp, 158K)
Global Climate Change and Environmental Stewardship by Ruminant Livestock Producers (PDF) (19 pp, 161K)
Opportunities To Reduce Anthropogenic Methane Emissions in the United States)

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Nutrient/Manure Management

Animal Feeding Operations (AFOs) are livestock-raising operations, such as hog, cattle, dairy, sheep, and poultry farms, that congregate animals, feed, waste, and production operations on a small land area. In these operations, food is brought to the animals rather than having them graze or otherwise seek food in pastures or fields. Manure and wastewater from AFOs have the potential to impact nearby water bodies and cause serious water quality and  public health risks.  AFOs can range from livestock production facilities with a small number of animals to extremely large production facilities that generate as much animal manure and wastewater as the amount of biosolids generated by a medium-sized city.  Improperly managed manure and wastewater from AFOs have been associated with significant environmental and public health concerns, including nutrient over-enrichment of surface water and groundwater, contamination of drinking water supplies and fish kills.

EPA is presenting a national strategy which describes the approach the Agency will follow in developing nutrient information and working with states and tribes to adopt nutrient criteria as part of state water quality standards. The strategy presents over enrichment assessment tools and recognizes current capabilities for conducting these assessments at the regional watershed and waterbody levels. The major focus of this strategy is the development of waterbody-type technical guidance and region-specific nutrient criteria by the year 2000. Once waterbody-type guidance and nutrient criteria are established, EPA will assist states and tribes in adopting numerical nutrient criteria into water quality standards by the end of 2003.

The major elements of this strategy include:

More information from EPA
EPA Region 3 Clean Bays Agreement with Perdue Farms, Inc. - EPA and Perdue Farms, Inc. have signed an agreement that will set up a program to help minimize the environmental impact that poultry farms have on the Chesapeake Bay and coastal bays around the Delmarva peninsula. The program initially focuses on the largest farms that supply Perdue with chickens. Under the formal Memorandum of Agreement known as the Clean Bays agreement, beginning in 2007 trained flock supervisors from Perdue will visit the farms to evaluate how they are controlling runoff and addressing litter disposal. The supervisors will use a checklist to examine how well the farms are complying with nutrient management regulations related to their poultry operations and identify areas for improvement.
Perdue Clean Bays Environment Management Initiative MOA (PDF) (5 pp, 224K)
Perdue Clean Bays Environment Management Initiative Fact Sheet (1 pg, 218K)
Region 3's AFO page
Managing Manure Guidance for CAFOs
National Strategy for the Development of Regional Nutrient Criteria
Section 319 National Monitoring Program Overview
Water Quality Trading
GreenScapes - provides cost-efficient and environmentally friendly solutions for large-scale landscaping.
GreenScaping for Homeowners: The Easy Way to a Greener, Healthier Yard - GreenScaping encompasses a set of landscaping practices that can improve the health and appearance of your lawn and garden while protecting and preserving natural resources.
Environmentally Preferable Purchasing - a federal-wide program that encourages and assists Executive agencies in the purchasing of environmentally preferable products and services.
AFO Virtual Information Center Nutrient Management - Information and tools to help develop nutrient management plans, including state technical standards.
An Urgent Call to Action: Report of the State-EPA Nutrient Innovations Task Group (PDF) (170 pp, 6.15MB) - the State-EPA Nutrient Innovations Task Group presents a summary of scientific evidence and analysis that characterizes the scope and major sources of nutrient impacts nationally.

Available software
Idaho One Plan Exit EPA - An innovative approach to conservation planning that enables farmers and ranchers in Idaho to identify and address multiple environmental agency requirements while ensuring a viable and sustainable approach.

Information from USDA
U.S. Pork Center of Excellence Exit EPA
Assessments to Reduce Nitrogen and Phosphorus Nonpoint Source Pollution of Iowa's Surface Waters

USDA Agricultural Research Service: Composting 
Manure Nutrients Relative to the Capacity of Cropland and Pastureland to Assimilate Nutrients
NRCS Animal Waste Management (AWM) Software Planning Tool -- estimates the production of manure in an operation (no cost to download); AWM Software Training video from Extension.org Exit EPA
NRCS Manure Master Decision Support System -- online software that compares nutrient content in animal manure with nutrients removed from fields where manure was applied
NRCS AFO Pro -- on line software allows the user to plan manure and commercial fertilizer allocation decisions in compliance with the NRCS’s 590 Standard

Information from Canada Exit EPA
Research Strategy for Hog Manure Management in Canada (PDF) (37 pp, 98.2K)
Nutrient Management Planning

Information from States Exit EPA

Comprehensive Nutrient Management Planning Resource from NASDA

Northeast Recycling Council's Manure Management Education -- provides assistance to small and hobby farmers/livestock owners to understand and adopt best management practices for handling and using manure. Key manure management resources include:

California Dairy Quality Assurance Program

The Do's and Don'ts of Dairy Manure Management and Clean Water (PDF)
(2 pp, 1MB)
The Do's and Don'ts of Dairy Manure Management Volume 2: Preventing Off-Site Discharge of Manure and Manure Pathogens (PDF) (2 pp, 2.7MB)

Clemson University
Land Application of Animal Manure (PDF) (8 pp, 294K)

Cornell University
Composting Manure 

University of Illinois
Manure Storage Entering Procedures
Illinois Certified Livestock Manager Training

Iowa State University
Iowa Manure Management Action Group (IMMAG)
Manure/Odor Management Publications

University of Maryland
Nutrient Management Program
Nutrient Management Publications

Generally Accepted Agricultural and Management Practices for Manure Management and Utilization

University of Minnesota
Manure and Odor Education and Research
Feedlot and Manure Management Directory
Manure Management and Air Quality

University of Missouri
Manure and Nutrient Management

University of Nebraska
Livestock Manure Management
Resources for Manure Management
Educational Videos: How to Install and use a Low Water Stream Crossing for Cattle (Real Player is required to view this) and How to Properly Decommission an Earthen Lagoon or Holding Pond

North Carolina State University
Nutrient Management
Waste Management Program

Ohio State University 
Best Management Practices: Land Application of Animal Manure
Ohio Livestock Manure And Wastewater Management Guide

Pennsylvania State University
Nutrient Management

University of Pennsylvania 
Center for Animal Health and Productivity
Dairy Nutrition and Management (scroll down)
Milk Urea Nitrogen

Purdue University 
Runoff Control Systems for Open Livestock Feedlots
Purdue Manure Management Planner (no cost to download)
Purdue Animal Manure Solutions
Purdue University Extension - Indiana Manure Locator Network

Texas A & M
Texas Animal Manure Management Issues

Information from Other Organizations Exit EPA
Anaerobic Digester Technology Applications in Animal Agriculture - A National Summit proceedings (June 2-4, 2003)
Farm Pilot Project Coordination (FPPC) - a non-profit organization, providing assistance in implementing innovative treatment technologies to address the growing waste issues associated with animal feeding operations (AFOs)
Livestock Waste Management - a project of the Conservation Technology Information Center
Manure Nutrient Management from eXtension.org.
Manure Treatment Technologies from eXtension.org.

Animal specific information Exit EPA

Swine Manure Management
Fertilizing Cropland with Swine Manure   

Dairy Manure Management
National Dairy Manure Management Database

Cattle Manure Management
Fertilizing Cropland with Beef Manure

Horse Manure Management
Clemson University (PDF) (2 pp, 120K)
British Columbia Ministry of Agriculture and Food (PDF) (4 pp, 1MB)

Poultry Manure Management
The Value and Use of Poultry Manures as Fertilizer

Alternative Treatment Technologies

More Information Exit EPA
Iowa Department of Natural Resources: Animal Feeding Operations New Rule Proposals
Manure Treatment Technologies from eXtension.org.

Information from Academic Institutions Exit EPA

Heartland Water Quality Project on Manure Management
Alternative Technologies
Feeding Strategies
Methane Digesters
Solids Separation
Vegetative Treatment Systems Resources
VTS Guidance

South Dakota State University
Research on vegetative treatment systems for dealing with manure from small afos

University of Nebraska
Case studies on vegetative treatment systems

Ohio State University
Farmstead Runoff Control

National Center for Manure and Animal Waste Management
Proceedings from the State of the Science Symposium on Animal Manure and Waste Management January 5-7, 2005, San Antonio, TX

Information from USDA

Agriculture Research Service
Vegetative Treatment Systems

Natural Resources Conservation Service
Vegetative Treatment Systems (PDF) (8 pp, 1.3MB) Exit EPA

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Carcass Disposal

Carcass disposal is an important consideration for livestock farming. Proper disposal of carcasses is important to prevent transmission of livestock disease and to protect air and water quality. Typical methods for the disposal of animal mortalities have included rendering, burial, incineration, and composting; each with its own challenges.

More information from other organizations Exit EPA
Managing Animal Mortalities Curriculum Materials from eXtension.org.
Carcass Disposal Information from VetCA.
2006 National Carcass Disposal Symposium Presentations - A list of presenters and presentations from the 2006 National Carcass Disposal Symposium. The symposium was hosted by the Maine Compost School.
2009 International Carcass Disposal Symposium - Proceedings from the July 2009 symposium: Three days of plenary, breakout, and poster sessions for researchers, policy makers, and regulators on carcass disposal technology, planning, and policy.

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Using the Clean Water State Revolving Fund to Reduce Animal Feeding Operation Pollution

The 25th anniversary of the Clean Water Act in October 1997 sparked the development of the Clean Water Action Plan (CWAP), which calls for a renewed commitment to providing "fishable and swimmable" waters to all Americans.  In creating the Clean Water State Revolving Fund (CWSRF), Congress ensured that it would be able to fund a wide range of water quality projects, including non-point source, wetlands, estuary, and watershed projects, as well as municipal wastewater treatment systems. The 51 funding programs (one in each state and Puerto Rico) work like banks. Federal and state contributions are used to provide capital or set up the programs. These assets, in turn, are used to make low-interest loans (as low as 0%) for important water quality projects. Loan repayments are then recycled to fund other important water quality projects.

Who is eligible?  Loan recipients are community groups, individuals, and agricultural and nonprofit organizations. Since the program is managed largely by the states, project funding may vary according to the priorities within each state. To obtain the funding, a project must be in a state's Non-point Source Management Plan or Estuary Conservation and Management Plan. Contact your state's Clean Water Act program for details.

Restrictions on eligibility.  Animal Feeding Operations that meet certain specified criteria in the National Pollutant Discharge Elimination System (NPDES) regulations are referred to as concentrated animal feeding operations (CAFOs). Under the Clean Water Act, CAFOs are point sources. Point sources can only receive CWSRF funding if publicly owned. However, a privately owned agricultural operation that includes a CAFO may still be eligible for CWSRF funding for a non-point source project if:

  1. The proposed remediation takes place outside the CAFO.
  2. The agricultural operation has a Comprehensive Nutrient Management Plan (CNMP) developed by a public official or certified private party and is implementing it.
  3. The proposed project is consistent with the Comprehensive Nutrient Management Plan.

At these facilities, for example, stormwater runoff from land application areas may be viewed as a non-point source discharge and eligible for the funding.

How much funding is available? The Clean Water State Revolving Fund has in excess of $27 billion in assets. Currently, it is funding approximately $3 billion in water quality projects each year. Funding for polluted runoff projects (including AFOs) is gaining momentum as the Clean Water Action Plan initiatives get under way.

Animal feeding operation success stories. 

More information from EPA
Cleaning Up Polluted Runoff with the Clean Water State Revolving Fund (PDF) (4 pp, 42.5K)
Financing Clean Water Action Plan Activities (PDF) (9 pp, 843K)
How to Fund Nonpoint Source & Estuary Enhancement Projects (PDF) (24 pp, 980K)
Funding Estuary Projects Using the Clean Water State Revolving Fund (PDF) (4 pp, 289K)
The Clean Water State Revolving Fund: Financing America's Clean Water Since 1987 - A Report of Progress (PDF) (20 pp, 294K)
State Revolving Fund Newsletter (PDF) (12 pp, 503K)
Clean Water State Revolving Fund: National Information Management System Reports (2006)
Clean Water State Revolving Fund Annual Reports

Contact information
EPA Clean Water State Revolving Fund Program
Washington, DC 20004
Phone: (202) 564-0752 Fax: (202) 501-2403
State Revolving Fund Regional Contacts (PDF) (1 pg, 19K)
State Revolving Fund Contacts

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Concentrated Animal Feeding Operations (CAFOs) confine livestock production in buildings or feedlots, producing large volumes of waste water. New or expanding CAFOs must apply for permit coverage under EPA's National Pollutant Discharge  Elimination System (NPDES) for wastewater. EPA must prepare environmental assessments or environmental impact statements, as required by the National Environmental Policy Act (NEPA), to assess the potential for impacts. Environmental assessments or environmental impact statements utilize information submitted by permit applicants in their Environmental Information Documents.

CAFOs, wastewater, and odors. Wastewater handling during animal housing, storage, treatment, and land application can cause odors which can impact neighbors if CAFOs are not managed to minimize odor production. Complaints by neighbors may lead to legal actions seeking court injunctions against EPA and others, including the applicants. To minimize odor impacts and minimize legal conflicts, EPA's environmental assessments need to consider potential odor pollution impacts from wastewater handling and discharge. However, applicants' Environmental Information Documents often contain little information on potential odor impacts, and if information is available the connection between management practices and odor may not be readily apparent to the permit reviewer.

Sources. Most notable about odor sources is that there are so many compounds potentially involved. Compounds may have their own odors, or they may combine with other compounds to produce different odors. The main classes of odor-causing chemicals are: volatile fatty acids, indols and phenols, ammonia and volatile amines, and volatile sulfur-containing compounds. Offensive odors can be generated by several parts of a CAFO, especially: 

  1. confinement buildings and open feedlots
  2. manure storage and treatment
  3. land application of wastes

For example, dust can carry odors from confinement building exhausts, and aerosols can carry odors from lagoons and from land application sprinklers.

Measurement. It is possible to measure some specific odor-causing chemicals.  However, a measured value of ammonia may have little to do with an actual perceived odor at a downwind location, which is more likely to result from a combination of chemicals.  As a result, odors are often measured using human panelists fitted with devices (olfactometers) which control panelists' intake of air in order to provide a consensus of sensory impact. Such field measurements form the basis for property-line odor regulations in several states and localities. Another way to measure odor is to use mathematical models to predict odor potential based on environmental characteristics such as terrain and wind speed. Modeling has not been developed to the point where compliance standards can be set.

Management. Management is the key to controlling odors. Odor-reducing management practices are available for all aspects of a CAFO, including site selection, building design, waste processing and disposal, and daily operation and maintenance. Often, good waste water management and control of odors go hand in hand, in that a clean, efficient CAFO produces less odor and more income at the same time.

Additives. It may be possible to reduce odors by modifying animal diet and wastewater treatment processes. Most feed and waste additives are commercial, odorant-specific, expensive, and require persistence. Their uses may best address short-term problems. The limited capability of additives to control odors makes it especially important that effective engineering and management practices be part of the original project design.

More information  Exit EPA

Air Quality in Animal Agriculture from eXtension.org.

More information from the States  Exit EPA

Swine Odor and Manure Management

Purdue University - PAAQL: Purdue Agricultural Air Quality Laboratory 

Livestock Odor Reduction Demonstration Project (PDF) (2 pp, 54.7K)
Manure/Odor Management Publications

Feedlots Livestock Odor FAQ
Biofilters for Odor Control (PDF) (2 pp, 217K)
Manure and Odor Management
Livestock Feedlots and the Environment (PDF) (3 pp, 146K)

North Carolina
NCSU - Swine Odor Management
NCSU - Cooperative Extension Service
NCSU - College of Agriculture and Life Sciences

Ohio State University - Ohio Livestock Manure and Wastewater Management Guide (PDF) (127 pp, 1.6MB)

South Carolina
Confined Swine Feeding Operations (PDF) (106 pp, 329K) - See SECTION 100.150 for Odor

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Livestock Environmental Stewardship Brochures

EPA developed pictorial brochures for four agriculture sectors (poultry, beef, dairy, and swine) to be used as compliance assistance tools. The brochures present management practices found at agricultural facilities. The goal of the brochures is to benefit the producer by identifying and promoting best management practices and environmental stewardship.

Related information
Livestock Environmental Stewardship Brochures

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Livestock and Poultry Environmental Learning Center

Livestock and Poultry Environmental Learning Center Exit EPA is a project sponsored by CSREES and dedicated to the vision that individuals involved in public policy issues, animal production, and delivery of technical services for confined animal systems should have on-demand access to the nation's best science-based resources.

The LPE Learning Center offers a free monthly webcast on a variety of issues related to animal manure management. The LPE Learning Center also offers a free monthly newsletter that includes information on the webcast series, new content, and innovative manure management resources and programs from across the country.

The Livestock and Poultry Environmental Stewardship Curriculum contains a series of lessons, CAFO fact sheets, Small Farm fact sheets, and Ag EMS publications. Continuing Education Units are available to Certified Crop Advisers (CCA) and members of the American Registry of Professional Animal Scientists (ARPAS).

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This page is sponsored by EPA's Ag Center. Ag Center logo

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