Emissions from Animal Feeding Operations

Executive Summary

This was a 3-year multi-institutional agricultural air quality research, extension, and education project with a multidisciplinary team comprising of air quality, agricultural, and environmental scientists to study the simultaneous emissions and fate of ammonia and hydrogen sulfide from confined animal feeding operations (CAFOs). As CAFOs have increasingly become subject to the state and federal regulations, there is an immediate need to develop improved emission inventories, with a view to enhancing the understanding of the fate and transport of emissions related to gases, odor, and particulate matter (PM). This will be undertaken using in-situ chemical and physical measurements. Improvements in the quantification of atmospheric sources and sinks of these compounds suggested by these measurements will be synthesized and incorporated in a comprehensive regional air quality model (Multiscale Air Quality Simulation Platform: MAQSIP) to assess the fate of these emissions on a regional basis, to provide quantitative estimates of the atmospheric budgets of these compounds, and to assess the potential impacts on airborne PMfine levels arising from changes in emissions associated with changes in future agricultural (both animal and crop) practices. Local and regional scale source – receptor relations were corroborated based on nitrogen and sulfur based isotopic studies, and back trajectory analysis.

The measurements was conducted in eastern North Carolina, and these results were extended to the southeast US. This analysis helped develop a comprehensive emission database for agricultural (animal and crop) practices, and provide input to state and federal agencies regarding the fate and transport of ammonia, ammonium, hydrogen sulfide, and sulfate compounds from CAFOs. Results were disseminated to agribusiness, regulators, and concerned citizens through a series of local meetings, workshops, fact sheets, news articles, and links to web sites. The project team worked directly with the North Carolina Environmental Management Commission (EMC), which was responsible for implementing regulations to protect air quality. Results can be used to modify regulations and policies to improve air quality management. New undergraduate and graduate courses and short courses on agricultural air quality (atmospheric nitrogen, sulfur, and particulate matter) were developed along with courses in transport, dispersion, and diffusion of air pollutants. These courses/short courses were offered to the stakeholder community, and students.