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The TOPOFF 4 Full-Scale Exercise

A Rigorous Full-Scale Response to a Coordinated Attack

Conducted in October 15-19, 2007, the TOPOFF 4 Full-Scale Exercise featured thousands of federal, state, territorial, and local officials. These officials engaged in various activities as part of a robust, full-scale simulated response to a multi-faceted threat. The exercise addressed policy and strategic issues that mobilized prevention and response systems, required participants to make difficult decisions, carry out essential functions, and challenge their ability to maintain a common operating picture during an incident of national significance.

As in a real-world response, agencies and organizations deployed staff into the field and faced realistic incident-specific challenges, including the allocation of limited response resources and exercise actions needed to effectively manage conditions as they emerge. Planning and preparation for the exercise also helped strengthen working relationships between departments and agencies that are critical to successful prevention and response in real emergencies. 

Extensive National Participation

The TOPOFF 4 Full-Scale Exercise involved more than 15,000 participants representing federal, state, territorial, and local entities. For the first time, a U.S. Territory, Guam, participated in the TOPOFF series, providing an opportunity to practice coordinated prevention and response activities between the continental U.S. and a U.S. territory. At the federal level, exercise play was marked by the coordinated participation of multiple agencies and departments. For example, in addition to response, the Department exercised prevention through its Terrorism Prevention Exercise Program (TPEP).

In the weeks leading up to the full-scale exercise, law enforcement and intelligence community players worked the information gathering, intelligence analysis, and information sharing capabilities that help to thwart terrorist activities. In addition, the U.S. Department of Health and Human Services mobilized around emerging public health issues related to a radiological emergency, and the U.S. Department of Defense ran concurrent exercises to address global terror threats. 

Exercise Scenario

The TOPOFF 4 Full-Scale Exercise was based on National Planning Scenario 11 (NPS-11). The scenario began as terrorists, who have been planning attacks in Oregon, Arizona, and the U.S. Territory of Guam, successfully bring radioactive material into the United States. The first of three coordinated attacks occured in Guam, with the simulated detonation of a Radiological Dispersal Device (RDD), or “dirty bomb,” causing casualties and wide-spread contamination in a populous area near a power plant. Similar attacks occured in the hours that follow in Portland and Phoenix. 

An RDD is not the same as a nuclear attack. It is a conventional explosive that, upon detonation, releases radioactive material into the surrounding area. Although it does not cause the type of catastrophic damage associated with a nuclear detonation, there are severe rescue, health, and long-term decontamination concerns associated with an RDD. Real weapons were not be used in the scenario, but the response will be mounted as if they had been.

Last Published Date: June 29, 2012
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