A SITE-SPECIFIC BIOSAFETY AND BIOSECURITY RISK ASSESSMENT FOR 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 a state of the art biocontainment facility, the National Bio and Agro-Defense Facility (NBAF), where comprehensive scientific research on the pathogens that may be involved would be performed. As part of the facility design and planning process DHS completed a Site-Specific Biosafety and Biosecurity Mitigation Risk Assessments (SSRA) in 2010 and 2012. The SSRA required a highly integrated multi-disciplinary probabilistic risk assessment methodology involving facility engineering design evaluation, source term analysis, site specific climatology development and analysis, fate and transport modelling, epidemiological modelling, economic impact modelling, and quantitative risk analytics. In order to estimate the potential health and economic consequences from an accidental or intentional airborne release of pathogens from the proposed NBAF facility, aerosol fate and transport simulations were performed to estimate downwind pathogen exposure to susceptible animal and human populations. Utilizing aerosol release parameters derived for each airborne transport scenario/pathway, aerosol airborne concentrations and surface depositions were calculated for a range of representative meteorological conditions, for the Manhattan, Kansas region where the NBAF facility will be located. For each individual aerosol exposure result, an associated probability of occurrence was provided, based on the relative frequency of the driving meteorological condition. To determine an overall risk ranking, these probabilities were later folded into the final occurrence frequencies for each scenario. This comprehensive assessment was developed by a collaborative team comprised of government, private sector and academic partners. In this presentation we will describe the unique multi-disciplinary risk analysis process used to develop the SSRA and how the atmospheric transport and dispersion was a key element of this analysis.