<i>A Dispersion-Based Tool for Assessing Odor Impact of Hog Operations</i>

Abstract. Odor impact from hog operations is often mitigated by establishing minimum separation distances between hog operations and neighboring residents/communities. A model was developed to calculate the separation distances in eight directions based on AERMOD simulations of odor dispersion and odor emission data from the literature. The separation distances were determined according to a user-inputted odor impact criteria considering both the odor concentration threshold and the frequency of odor annoyance free. The model considered odor emission from hog buildings and manure storage, as well as the use of odor abatement methods for buildings and manure storage. AERMOD simulations were based on Prognostic Mesoscale Meteorological data for the specific regions of interest. A case study was performed on a fully-slatted, shallow pit hog facility with 5935 finisher pigs.