Authors: Chip Simmons, PhD, Assistant Research Professor at the University of North Carolina at Chapel Hill, School of Public Health, and Mark Rice, Extension Specialist at North Carolina State University
Farm-specific information (land available, hauling distances, etc.) on a case-by-case basis is needed to answer this question and is based on the economics of the individual situation. Based solely on an on-farm economic standpoint, it is doubtful that there will be any technology "lower cost" than lagoons or pits, but if hauling distances are great, solid/liquid separation may help reduce cost by reducing the volume being transported to distant fields. Unfortunately, solid/liquid separation of swine waste, without the proper specialized equipment, is not particularly efficient, especially following storage. One of the reasons that anaerobic lagoons are not used in these locations is that, with the lower average temperature (anaerobic lagoons rely on biological processes which slow considerably with cold temperatures), a lagoon system would need to be several times larger to accomplish the same degree of solids and odor treatment. Some literature demonstrates as much as two to three log10 reductions for several classes of microbial pathogens using thermophilic (>55°C) anaerobic digestion. However, this technology generally does not fit the request for a “lower cost alternative.”
In situations where treatment technologies that greatly reduce pathogen concentrations are not available, other barriers to pathogen transmission must be considered including reducing the potential for pathogens entering the farm and cross animal contamination within the farm (http://lpe.unl.edu/pathogen5.html#q1) and limiting movement of pathogens associated with land application practices (http://lpe.unl.edu/pathogen5.html#q2)
To access potential alternatives NRCS practice codes, go to http://www.nrcs.usda.gov/technical/efotg/, click on your state, and then click on your county. Next open “Section IV” (left-hand column) and “Table of Contents” to find individual practices.
