Nutrient Management: Air and Water Quality Issues

by 5m Editor
30 January 2006, at 12:00am

By G.T. Tabler, Poultry Science Department at the University of Arkansas's Avian Advice - The countryside has long been the place to live or retreat to for fresh air and clean water. However, rural America is also home to production agriculture that feed this country and much of the rest of the world.

Nutrient Management: Air and Water Quality Issues - By G.T. Tabler, Poultry Science Department at the University of Arkansas's Avian Advice - The countryside has long been the place to live or retreat to for fresh air and clean water. However, rural America is also home to production agriculture that feed this country and much of the rest of the world.


As farms become fewer in number, yet larger in size, nutrient management becomes an increasingly difficult concern for farmers as well as the general public, governmental agencies at the local, state and national level.

Arkansas poultry farms are a perfect example of this dilemma. Poultry litter may simultaneously affect more than one environmental medium (such as both air and water quality). Unfortunately, most current environmental laws tend to ignore the big picture to focus on specific environmental areas (e.g., Air in the Clean Air Act and Water in the Clean Water Act). Yet comprehensively addressing regulatory concerns avoids unnecessary costs to producers and assists in efficiently dealing with environmental issues.

Arkansas Rule Changes

Without question, we currently have access to more data concerning water quality than air quality. So much so that in 2003, the EPA introduced revised Clean Water Act regulations to better protect surface waters from nutrients from concentrated animal feeding operations (CAFOs). As a result, when applying manure to crop or pasture land (still the most common disposal method), CAFOs must now follow a nutrient management plan that specifies a manure application rate that minimizes the threat to water quality.

The situation in Arkansas is such that starting January 1, 2006, dry poultry litter may only be applied in accordance with a nutrient management plan or at the maximum application rate of 1.5 tons per acre. Starting January 1, 2007, the maximum application rate of 1.5 tons per acre will no longer be valid and dry poultry litter must only be applied in accordance with a nutrient management plan.

Also, anyone applying nutrients to an area greater than 2.5 acres is required to become a certified nutrient applicator, regardless of whether poultry litter or commercial fertilizer is being applied. The training curriculum is the same for either a private or commercial applicator. However, the fees are different, $30 for a private and $60 for a commercial, and commercial applicators are required to take an exam following the training and pay an exam fee. You may contact your local county extension office if you have questions or need additional information.

Emission Concerns

While water quality has been a concern for a number of years, as farming operations become larger through consolidation and increasing numbers of people have moved from cities to rural areas, agricultural air quality has become a major issue. Air quality is regulated by the Clean Air Act and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The Clean Air Act sets limits on how much of a given pollutant can be in the air anywhere in the United States.

Regulation of air emissions under the Clean Air Act and CERCLA has, until recently, focused on sources such as factories and cars, not agricultural emissions. However, agricultural emissions now have the attention of the federal government and changes to air quality regulations that may affect how you manage your operation are likely forthcoming. States are responsible for abiding by the Clean Air Act. Recent lawsuits, court decisions, and consent agreements have spurred some states to begin regulating agricultural emissions.

California was the first state to implement air quality regulations that significantly affect agriculture. However, without careful planning and consideration of nutrient regulations already in place, implementation of new air quality regulations may create a nightmare for producers.

Emissions from agricultural facilities to the atmosphere do not occur in isolation. Biological and chemical processes ensure that water and air pollution concerns are closely linked. For example, when poultry litter is spread on a field, some of the nitrogen is volatilized into the atmosphere, which lessens the amount that may wind up in the soil profile and therefore, decreases the risk to water quality. However, the amount that is volatilized increases the risk to air quality by creating odors, contributing to fine particulates (haze), and hastening global climate change (National Research Council, 2003).

Multimedia Approach

The current uncoordinated approach to air and water quality regulation has potentially costly implications for both animal producers and society in general (Aillery et al., 2005). Some animal feeding operations already subject to water quality regulations may soon be required to meet ammonia emission regulations as well. Technologies adopted to reduce water pollution may be inadequate for meeting both water and ammonia requirements, and might have to be abandoned or modified, at some cost, to comply with both sets of regulations (Aillery et al., 2005).

The increasing size and geographic concentration of animal feeding operations, driven by the economics of domestic and export markets for animal products have resulted in large quantities of nutrients accumulating in relatively small areas. According to a 2003 National Academy of Sciences study, animal feeding operations are the primary source of ammonia emissions in the U.S., and ammonia emissions are already a concern in some rural areas (Ribaudo and Weinberg, 2005). Additional data is certainly needed regarding air emissions from animal agriculture and efforts are currently underway on several fronts to provide this information. It would appear more advantageous to use this data, when available, in combination with water quality efforts already in place rather than develop a completely independent air quality program.

Within the past 10 years, the EPA has developed integrated air and water rules that set emission levels and has coordinated implementation of the Clean Air Act, Clean Water Act, and Resource Conservation and Recovery Act (which deals with hazardous waste disposed on land). This approach is designed to decrease implementation costs and assist regulated industries in the efficient organization of pollution control activities through a combination of source reduction technologies and management practices, air pollution control devices, and upgrades on existing wastewater treatment systems (Ribaudo and Weinberg, 2005).

Would such a coordinated implementation effort be advantageous to the poultry industry? At present many producers are not aware of their operation’s contribution to emissions or whether they are subject to existing air quality regulations. Knowing the legal and financial risks for different operations would help producers make proper decisions, avoid lawsuits and remain in business. Also, it should be kept in mind that a coordinated effort that benefits both air and water quality is likely much more workable than two independent systems where benefits to one is at the expense of the other.


The Clean Water Act has regulated many CAFOs since 1974; many more (including a number of dry-litter poultry farms) will be regulated as a result of strengthening of regulations in 2003. Air emissions from animal agriculture (including poultry houses) are currently attracting much local, state and national attention. Poultry producers should monitor the situation closely as this will likely affect your operation in the near future. A number of new regulations regarding nutrient management and spreading litter will soon go into effect for Arkansas poultry producers. Stay current on rule changes to avoid serious legal issues. Contact your local county extension office with questions.


Aillery, M, N. Gollehon, R. Johansson, J. Kaplan, N. Key, and M. Ribaudo. 2005. Managing manure to improve air and water quality. USDA ERS. Economic Research Report 9.
National Research Council. 2003. Air emissions from animal feeding operations: Current knowledge, future needs. Ad Hoc Committee on Air Emissions from Animal Feeding Operations, Committee on Animal Nutrition, National Research Council, National Academy Press, Washington, DC.
Ribaudo, M.and M. Weinberg. 2005. Improving air and water quality can be two sides of the same coin. Amber Waves. Sept.

Source: Avian Advice - Fall 2005 - Volume 7, Number 3