Comparative Risk Analysis of Abandoned Manure Basins.

Utilization of earthen manure basins to store animal wastes is common practice throughout Minnesota due to their effectiveness and relatively cheap construction costs. Manures within these basins are a valuable source of nutrients for crops, however they must be managed appropriately to protect water resources. Some contaminants found within animal manures can pose a potential human or environmental health risk. One area of manure management which has not been thoroughly investigated is the risk posed by manure basins to water resources upon closure. A comparative risk assessment was performed on eight manure basins located in Stearns County, Minnesota. The risk assessment determined the amount and forms of contaminants present, compared risk levels to adjacent lands, and assessed the overall human or environmental health risks associated with manure basin closure, if any. Soil and groundwater sampling was conducted at each site. Statistical analysis was used to determine the comparative risks abandoned basins have to surrounding land use areas.