WHY A DESIGN BASIS THREAT?

The Commission concluded that protection of the public health and safety required physical security at certain nuclear facilities to protect against radiological sabotage or theft of nuclear material. However, no credible threat to nuclear facilities existed against which security systems could be designed. Therefore, the problem was to achieve an appropriate, consistent, and effective level of physical security against radiological sabotage at all nuclear power plants and against theft at certain nuclear fuel cycle facilities in the absence of any existing credible threat. The solution took the form of a hypothetical threat, or design basis threat, comprising certain adversary characteristics that when used for the design of a physical security system would pro- vide the desired level of protection. In select- ing the adversary characteristics that composed the design basis threat, extensive study was made of the historical record and discussions were held with experts on terrorism, crime and physical security. Then the proposed design basis threat was subjected to review, comment and compared to the results of subsequent confirmatory research. As articulated in the late 1970's, the design basis threat represented a reasonable character- ization of a possible adversary force that could also serve as a baseline for designing a physical security system. Thus, the design basis threat serves as the foundation for physical security for key nuclear facilities in this county. To assure that the design basis threat remains a valid and reasonable baseline threat character- ization, the NRC, on a daily basis, monitors the threat environment, foreign and domestic. This activity includes the assessment of reported threats to NRC licensed facilities and activ- ities, the review and evaluation of intelligence reporting, and regular meetings with represen- tatives of other Federal agencies. NRC senior management is periodically informed on the results of the staff's efforts to assure the continuing validity of the design basis threat.