2002 Annual Report
Research
Evaluation and Implementation of OFFSET (Odors from Feedlot Setback
Estimation Tool) in Selected Minnesota Counties
Larry Jacobson, Professor
Kevin Janni, Professor
David Schmidt, Assistant Extension Engineer
Sven Nimmermark, Graduate Student, Swedish University of Agricultural
Sciences
Funding Source
Minnesota Agricultural Experiment Station Rapid Agricultural Response
Fund
Objective
To evaluate the OFFSET (odor setback) tool in several Minnesota counties
for ease of understanding, implementation and performance in various situations.
Project Description
During this project, team members worked with county feedlot staff in
five Minnesota counties (Carver, Nicollet, Stearns, Steel, and Winona)
to assess the impact of the resulting setback distances on current and
future land use planning needs. County staff and project team members
worked together to select appropriate farms to conduct field evaluations
for assessing OFFSET and suggest necessary changes in the tool, if needed,
to insure it is a valid method for predicting odor impacts. Project members
continue to provide technical support to the county feedlot staff.
Results
Initial meetings with county feedlot officers were held in fall 2000. Tentative plans were discussed and feedback on the present status of setback recommendations was received. Specific animal production sites were selected in each of the five counties along with individuals living near these farms (within approximately one mile) for odor monitoring. Two-hour training sessions were held in each county for the odor monitors to establish criteria for odor intensity determination of odor events that they recorded through November 1, 2001. Weather stations were also established in each county during the odor monitoring season. During the summer of 2001, air samples were collected from each of the animal production sites and analyzed for odor intensity and emission rates. The measured emission values were used to predict odor intensity levels with OFFSET and were compared to those determined by the community or neighbor monitors. The data is under review and a report is being written. The report will be circulated to the cooperating counties for feedback before the report is finalized.