be transported to their final place of use by truck, rail, pipeline, marine vessel or other means in both large and small quantities.

This study was requested by DHS to assist the department in characterizing and mitigating the vulnerabilities faced by the nation from its chemical infrastructure (see Appendix B for full statement of task). The study has examined classes of chemicals and chemical processes that are critical to the nation’s security, economy, and health; identified vulnerabilities and points of weakness in the supply chain for these chemicals and chemical processes; assessed the likely impact of a significant disruption in the supply chain; identified actions to help prevent disruption in the supply chain and actions to mitigate loss and injury should such disruption occur; identified incentives and disincentives to preventive and mitigating actions; and recommended areas of scientific, engineering, and economic research and development that might advance the nation’s capability to protect against such losses and minimize their impact.

This report addresses the most significant general types of vulnerabilities associated with the chemical infrastructure, not site-specific vulnerabilities. Other government and private sector efforts are developing vulnerability and risk assessments that account for site-specific factors such as the amount of chemical on a site and the size of the potentially affected population near a site. This study is intended to supplement those efforts.

This report adopts the definition of catastrophic incident outlined in DHS’s National Response Plan—one that “results in large numbers of casualties and/or displaced persons, possibly in the tens of thousands.” Similarly, an economic impact on the order of tens to hundreds of billions of dollars would be considered catastrophic. A catastrophic event is one whose consequences are so extensive that they overwhelm the ability of emergency responders, local and federal government officials, and/or the general public to adequately and/or fully respond in a timely fashion.

Toxic, flammable, and explosive materials present the greatest risk of catastrophic incident.