not already occurred. Additionally, there have been more than a dozen seizures of SNM from Russia and surrounding countries since the early 1990s. Most of the seized materials are thought to have been smuggled from Russian civilian nuclear sites.
Stocks of SNM also could be produced clandestinely, either through enrichment of uranium or reprocessing of spent nuclear fuel to recover plutonium. Uranium enrichment is equipment intensive and time consuming, and detection is increasingly likely as the scale of operations is increased. A small-scale program could potentially be hidden through careful facility design, however, and could, in principle, produce sufficient material for a weapon if operated for several years. Reprocessing to recover plutonium also can be carried out in small, difficult-to-detect facilities but requires access to irradiated reactor fuel. Any country with a research reactor has potential access to such fuel, and there are, in addition, large stocks of spent fuel in power reactors in countries of the former Soviet Union and also in foreign research reactors, some of which still operate with HEU. Clandestine production of SNM by states or terrorist groups for use against the United States represents a significant near-term threat to homeland security.
The threats considered here include attacks on nuclear power plants (both commercial nuclear power plants (NPPs) and research reactors), their spent fuel storage facilities, and spent fuel transportation casks; detonation of conventional explosive devices packed with radioactive materials, so-called “dirty bombs;” and the surreptitious placement of radiation sources in places frequented by large numbers of the public. Attacks on DOE-owned nuclear facilities were not considered because these are generally considered to be hardened and well protected.
The United States has 103 operating civilian nuclear power reactors at 65 sites that generate about 20 percent of the U.S. electrical supply (USNRC, 2002; EIA, 2002). The U.S. Nuclear Regulatory Commission (USNRC) regulates NPPs and has had a long-standing concern about security and safeguards. The agency’s security and safeguards regulations are extensive and actively enforced.
The USNRC requires that NPPs be protected against a “design basis threat,” defined at present to involve a ground attack by a group consisting of several armed terrorists aided by an inside collaborator.4 NPPs are required to train their