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Accident Response Group

NNSA's Accident Response Group (ARG) provides technical guidance and responds to U.S. nuclear weapons accidents.  ARG_LogoThe team assists in assessing weapons damage and risk, and in developing and implementing procedures for safe weapon recovery, packaging, transportation, and disposal of damaged weapons.  The ARG headquarters is located in Albuquerque, New Mexico and is supported by Lawrence Livermore National Laboratory, Los Alamos National Laboratory, Sandia National Laboratories, Remote Sensing Laboratory (RSL), and Pantex Plant.


ARG personnel performing operationsThe mission of the ARG is to maintain readiness to respond and manage the resolution of accidents, or incidents of significance involving nuclear weapons.   The ARG staff includes scientists, engineers, technicians, health physics and safety specialist from NNSA's and the Department of Energy's national laboratories.  The Phase I team can respond within four hours of notification, and deploy with highly specialized state-of-the-art equipment for use in monitoring, assessing, and removing nuclear weapons, and their components.

Steps in the ARG Response

If an accident or incident involving a U.S. nuclear weapon occurs, all appropriate federal, state, tribal, and local organizations are notified of the accident. The NNSA and Department of Defense (DoD) work as a team throughout the entire response.

  • Recovery of the damaged weapon or its components begins with locating the weapon and gaining access to it, with safety being the prime consideration.
  • Team members will then assess the configuration, or structural arrangement of the damaged weapon, in order to make it safe to move (also known as "render safe"). Since nuclear weapons contain chemically reactive materials and radioactive elements, great care must be taken in gaining access to them.
  • Radiography can then be used to examine the weapon’s internal structure. If there is damage to the weapon or its components, special techniques may be used to stabilize the internal components.
  • Then, team members use specialized equipment to cut away the wreckage, and gain access to the weapon.
  • Once the weapon recovery operations are complete and the weapon and its components are packaged and contained, the agency (NNSA or DoD) responsible for the weapon involved in the accident conducts site restoration operations.
  • The ARG's mission continues until the weapon, and its components are transported to their final disposition site.

ARG personnel performing operationsHowever, once the weapon has been safely removed from the site, NNSA's role turns to monitoring and assessment activities, which are conducted by other NNSA assets to include:  the Aerial Measuring System (AMS), the National Atmospheric Release Advisory Center (NARAC), the Federal Radiological Monitoring and Assessment Center (FRMAC), Radiological Assistance Program (RAP), and the Radiation Emergency Assistance Center / Training Site (REAC/TS).


The ARG's capabilities are provided in a time-phased approach:  

  • Phase I, called the Initial Response, is a six person team that provides technical advice to the U.S. military Explosive Ordnance Disposal operators, to determine weapon damage, and conduct the initial risk assessment.
  • Phase II, called Recovery Operations, is a 38-person team with the ability to conduct 12-Hour operations to safely recover the damaged nuclear weapon.
  • Phase III, called the Follow-On Response, is a 34-person team, which expands Phase II operations to conduct 24-Hour recovery operations, and package, and arrange transport of the damaged nuclear weapon for disposition.

Additionally, the ARG communicates with the ARG home team, which is designed to support NNSA with resources and technical expertise from the national laboratories.