Researchers hope the results of an air quality study will help them find ways to reduce gas emissions from livestock.

The six-state study monitored the air quality near swine and poultry facilities. Emissions from the Iowa site were a little higher than those gathered in Texas, and one possible reason could be attributed to the different type of manure management, said Jacek Koziel, assistant professor of agricultural and biosystems engineering and former faculty member at Texas A&M University. He was also a member of the Texas research team.

Unlike Iowa’s deep pit system, where manure can reside in a barn for up to one year, the facility in Texas used a shallow pit, where manure is removed weekly, he said.

“This study is really the first comprehensive study in the United States in evaluating emissions from these facilities,” said Steve Hoff, professor of agricultural and biosystems engineering.

Researchers monitored gases and particulate levels at four swine and two poultry production systems, Hoff said. The study is important because it gives researchers good, scientific information that, in turn, will allow the Environmental Protection Agency to make the right decision about emissions regarding these types of facilities.

The purpose was to gather base-line data on emissions that could be used for smell and dust reduction methods, Hoff said.

“By putting the data against a new technology, you’re able to judge its effectiveness,” he said.

Koziel said before this study, Texas had no long-term data regarding air pollutants from swine.

Air samples were taken from the facilities between October 2002 and March 2004. Samples were taken from sites in Illinois, Indiana, Iowa, Minnesota, North Carolina and Texas, according to a press release from the College of Agriculture.

A mobile emissions laboratory monitored four building sites that housed 1,000 pigs in each structure and included deep pits under the buildings that could store one year’s worth of manure.

Hoff said it is not easy to compare one state’s emissions levels to another because each state utilizes different productions systems.

Koziel agrees.

Some producers may still have to report certain emission levels.

Larger facilities, those holding 2,300 animals or more, will have to report to the EPA every year that they probably exceeded ammonia levels of 100 pounds per day; ammonia is a limiting gas that triggers what the EPA calls “reportable quantity,” Hoff said.

“Right now, it’s simply a reportable quantity. There’s no penalty as far as I know,” he said.

Along with the University of Minnesota and the University of Nebraska, Iowa State is leading a three-state study that will monitor and develop odor dispersion models.

Hoff said field data will be collected from facilities and locations downwind that will be used to evaluate odor dispersion models and assist in evaluating future sites of swine and poultry production systems.

A final report will be submitted to the United States Department of Agriculture in September. The report could also include data from North Carolina where field studies are still being conducted.