National Nuclear Security Administration

Gamma Shield Thunder Exercise Concludes

September 17, 2015

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National Nuclear Security Administration (NNSA) and the FBI announced today the completion of the Gamma Shield Thunder counterterrorism table-top exercise at LDS Hospital.  The exercise is part of NNSA’s Silent Thunder table-top series, which is aimed at giving federal, state and local officials, first responders and law enforcement critical, hands-on experience in responding to a terrorist attack involving radiological materials.

The NNSA began the Weapons of Mass Destruction (WMD) Counterterrorism Exercise Program in 1999. It has grown to include both domestic Department of Energy facilities and private sector locations such as hospitals and universities. The exercises have been carried out primarily within the United States, but have included foreign participants as well.

The Silent Thunder exercise program, developed and conducted in partnership by NNSA and the FBI, directly addresses dangers of nuclear terrorism. To date, NNSA and the FBI have conducted Silent Thunder exercises in 22 states and the District of Columbia, with plans to reach additional states in the future.

The exercise series recognizes that reducing the risk of radiological or nuclear terrorism requires a whole-of-community approach that brings together officials and responders from the federal, state, local and facility levels.

"I was really impressed by the commitment and enthusiasm the folks from facility, local and state emergency services demonstrated," said Derek Estes, who led the Federal team that organized the exercise. "We've seen a real growth in readiness across the emergency management community we work with nationally."

This Gamma Shield Thunder exercise played out a fictitious scenario where terrorists attempted to seize control of a high-activity radiological sources by infiltrating hospital facilities. The participating officials worked cooperatively to assess and respond to simulated facility alarms and then manage the crisis as if it were actually happening. The goal of these exercises is to provide first-hand crisis management experience, facilitate coordination between multiple agencies and improve both security and emergency response methods. Exercises take place in select locations across the country with facilities that house nuclear or high-activity radioactive materials.

“From Intermountain Healthcare Central Region’s perspective, this exercise allowed us to achieve a number of goals,” said Central Region Director of Safety and Security Glen Buma. “We were able to evaluate the region’s procedures and tactical decision making, exercise our mutual aid and Unified Command structure, improve communication and interoperability between local law enforcement and surrounding jurisdictions and evaluate our resiliency planning and continuity of operations.  Overall, this was an excellent experience that provided enormous benefit to our region’s hospital preparedness.” 

The exercise series is jointly organized and funded by NNSA’s Global Material Security (GMS), NNSA’s Office of Counterterrorism Policy and Cooperation, and the FBI. The federal agencies participating in Gamma Shield Thunder were joined by authorities representing federal, state, county and municipal agencies including:   the U.S. Nuclear Regulatory Commission Region IV; U.S. Department of Homeland Security; Radiation Emergency Assistance Center/Training Site (REAC/TS); Sandia National Laboratories; the 85th WMD Civil Support Team; State of Utah Agencies:  State Intelligence Fusion Center; Department of Public Safety, Department of Environmental Quality, Department of Health; Salt Lake City and County Health Departments; Salt Lake City Emergency Management; Murray City and Salt Lake City Fire Departments, Murray City and Salt Lake City Police Departments, and Intermountain Healthcare, Inc. representatives.

NNSA’s GMS, in coordination with the Nuclear Regulatory Commission (NRC) and the Department of Homeland Security, installs voluntary security upgrades at hospitals and other civilian sites housing high-activity radiological sources that are commonly used in medical procedures and other commercial activities. Preceding the Gamma Shield Thunder exercise, Central Region instituted these GMS radiological security improvements. These security upgrades further reduce the potential for theft or misuse of radiological materials that could be used in a dirty bomb. These voluntary upgrades are in addition to increased security enhancements required by NRC and NRC agreement states since 2006.

Started in 1999, NNSA’s Office of Counterterrorism Policy and Cooperation’s WMD Counterterrorism Exercise Program took on an expanded role following the tragic events of Sept. 11, 2001. Since the program began, over 8,700 international, federal, state and local officials have participated in 100 different exercises. To promote full participation by state and local officials, Silent Thunder exercises are unclassified and utilize open source information for scenario development and are conducted in a no-fault environment.


Established by Congress in 2000, NNSA is a semi-autonomous agency within the U.S. Department of Energy responsible for enhancing national security through the military application of nuclear science. NNSA maintains and enhances the safety, security, reliability and performance of the U.S. nuclear weapons stockpile without nuclear testing; works to reduce global danger from weapons of mass destruction; provides the U.S. Navy with safe and effective nuclear propulsion; and responds to nuclear and radiological emergencies in the U.S. and abroad.