A Site-Specific Biosafety and Biosecurity Risk Assessment for the Impact of a Tornado on the National Bio and Agro-Defense Facility (NBAF)

Foreign animal, emerging, and zoonotic diseases present a significant threat to the United States economy, agricultural security, and public health. To address this threat, the Department of Homeland Security is currently designing and building a state of the art biocontainment facility, the National Bio and Agro-Defense Facility (NBAF), where comprehensive scientific research would be performed on the pathogens involved. As part of the facility design and planning process, DHS completed Site-Specific Biosafety and Biosecurity Mitigation Risk Assessments (SSRA) in 2010 and 2012. Because the NBAF will be built in Manhattan Kansas, an area where strong tornadoes are prevalent, it was necessary for the SSRAs to include a detailed risk analysis for scenarios where the facility was hit and damaged by a tornado. This tornado impact risk assessment used a methodology that combined a location specific analysis of the regional tornado climatology that drove the corresponding atmospheric dispersion simulations to characterize airborne concentrations and surface depositions of bio-aerosols. A unique aspect of this study was how the climatological record of tornado incidents in the Manhattan Kansas region was combined with the self organizing map (SOM) methodology to more robustly identify the corresponding weather patterns representative of days where tornados might occur. The results of this analysis along with the probabilities of the tornado strike were then used to determine the overall risk of infection and corresponding economic risk associated with that scenario for comparison with other risk scenarios. In this presentation we will describe this unique multi-disciplinary risk analysis process and illustrate how it provided a means to determine the SSRA for a rare atmospheric event like a tornado.