Did You Know?

Subway systems are attractive targets for chemical and biological terrorism due to large numbers of people in confined spaces and necessarily limited security. In the case of biological agent attacks, hazardous exposures can occur not only in the subway itself but also throughout the city as the material is ejected to the outdoors through vents, station entrances and other openings to the exterior and then carried by the wind. A chemical attack would generally be more limited in scope but can still pose substantial hazards as evidenced by the 1995 Aum Shinrikyo sarin attack in the Tokyo subway.

Opportunity

While the subway system can be an efficient avenue to spread materials across a large urban area, the efficient and rapid transport of materials in the subway allows for considerable opportunities of detection and response.

Solution

To address these threats, Argonne researchers have developed a computational modeling suite, the cornerstone of which is the ANL Below Ground Model. The model not only assesses the transport and dispersion of a chemical or biological agent plume, but also tracks each individual passenger in the subway system so that (1) casualties can be estimated and (2) their effect on the agent plume itself can be measured.

Results

The results of this research are many fold. We have been able to estimate the effects of both chemical and biological agent attacks, design detection architectures using COTS technologies, and have given stakeholders and policy makers actionable information as to the degrees of the subway threats and how best to respond.