United States Department of Agriculture
Natural Resources Conservation Service
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Particulate Matter and Animal Operations

What is Particulate Matter (PM)?

Particulate matter (PM) is currently a “criteria air pollutant” which means that the US Environmental Protection Agency (EPA) has identified PM as a pollutant that causes significant health (heart and lung) and environmental (deposition, visibility) effects. PM can be either solid particles or liquid droplets and come in a variety of sizes, shapes, and chemical composition. PM can be emitted directly (primary PM - dust, pollen, soot, etc.) or formed in the atmosphere (secondary PM – formed from the reactions and condensation of sulfates, nitrates, volatile organic compounds [VOCs], and ammonia). The EPA has currently established National Ambient Air Quality Standards (NAAQS) for two forms of PM:

  • Fine PM – currently regulated as PM2.5 (aerodynamic diameter less than or equal to 2.5 micrometers) Note: The diameter of the average human hair is 70 micrometers.
  • Coarse PM – currently regulated as PM10 (aerodynamic diameter less than or equal to 10 micrometers)

Larger size fractions of PM such as total suspended particulate (TSP) are also regulated by state or local regulatory agencies. The federal PM standards have been adopted by the State of Montana.

Where is PM a Concern?

PM can be a local (deposition or transport), regional (formation and transport ), and global (transport) concern. Greater emphasis on addressing PM concerns is likely to occur in areas that do not meet the PM NAAQS or have other PM issues such as regional haze or local deposition and visibility effects. Several communities in Montana do not currently meet state and/or federal air quality standards. For a current list of PM nonattainment areas see the Montana Department of Environmental Quality Air Quality Info Web page.

How Do Animal Operations Affect Ozone?

Animal operations can influence PM in a variety of ways, including:

  • Animal activity can produce dust emissions which can be carried by wind or building ventilation.
  • Feed, material, and manure storage and handling can produce dust emissions.
  • Combustion in on-farm equipment can produce fine PM and other by- products that lead to PM formation.
  • Manure decomposition and land application can produce emissions of ammonia and VOCs.

What Can I Do?

Many common practices and management activities can help reduce the likelihood of particulate matter impacts from animal operations. The following suggestions are not all-inclusive but offer some options that are available for managing the particulate matter. Talk with your NRCS conservation professional about what specifically will work best on your land.

Concentrated Operations
  • Maintain appropriate housecleaning techniques (clean up spilled feed, bedding, etc.)
  • Maintain appropriate housing ventilation.
  • Maintain appropriate moisture content in open lot surface (use sprinklers, etc.)
  • Periodically remove manure.
  • Use a liquid manure management system as opposed to a solid manure management system.
  • Cover the surface of storage piles of manure, bedding, feed, etc.
  • Remove feed and manure from storage piles in a manner that minimizes surface disturbance.
Pasture or Range Operations
  • Use prescribed grazing and/or range management to maintain adequate vegetative cover, minimize manure accumulation, and reduce burning requirements; or minimize residual biomass.
  • Implement alternatives to forest or rangeland burning, such as removing biomass via grazing or developing biofuels.
  • When forest or rangeland burning is necessary, promote an efficient burn and develop and implement prescribed burn and smoke management plans.
Miscellaneous
  • Install windbreaks or shelterbelts to intercept or disperse PM.
  • Avoid spilling feed and other materials.
  • Implement speed restrictions or access barriers on roads.

For More Information

NRCS in Montana is currently developing guidance and conservation practice standards for addressing all aspects of air resource issues at animal operations. For more information contact your local NRCS Field Office. A list of NRCS offices in Montana can be accessed at Local NRCS Service Centers (Field Offices) in Montana.

Primary Contact

Tom Pick
Water Quality Specialist and Air Quality Contact
Phone: 406-587-6947
E-mail: Thomas.Pick

This information is also available in Adobe Acrobat format.

Particulate Matter and Animal Operations (PDF; 266 KB)

Last Modified: 05/23/2008