National Air Emission Monitoring Study: North Carolina Swine Sites.

The National Air Emissions Monitoring Study (NAEMS) was conducted according to the U.S. EPA air consent agreement, in which livestock producers agreed to collect air emission data in exchange for more time to report their emissions and apply for any necessary permits. The NAMES provided a unique opportunity to continuously monitor several pollutants measured simultaneously over long periods of time (2 years) at a large number of measured barns (38) using the same protocol. Information is presented on gas and particulate emission results from a finishing farm (~ 2500 head capacity) and a sow farm in NC. Daily ammonia (NH3) emission rate in the finishing farm ranged from 2 to 16 g/head-day showing its variation by season as well as growth stage during a fattening period. Average daily hydrogen sulfide (H2S) emission rate was 220 mg/head-day, and the H2S emission rate was affected by growth stage and pit manure management practices. Daily mean particulate matter (PM10) emission rate were between 400 to 800 g/day when the barns were fully occupied by hogs, and <100 g/day when the barns were empty. Further comparison of emission rates with sow farm operations (i.e., farrowing, breeding, and gestation) will be discussed.