Potential Radioactive Releases from Commercial Reactors and Spent Fuel*

Commercial nuclear reactors and storage facilities for their spent fuel contain large amounts of radioactive material, and are not designed to resist attack. The US Nuclear Regulatory Commission (NRC) has determined, however, that these facilities require only a light defense. This paper shows, without disclosing any sensitive information, that reactors and spent-fuelstorage facilities have vulnerabilities that could be exploited by knowledgeable and determined attackers, yielding atmospheric releases including tens of MCi of cesium-137. To address this threat, measures described here could provide enhanced defense of reactors and spent fuel, thereby reducing the potential for a large release. A high-priority measure would be to equip spent-fuel pools with low-density racks, storing the remaining spent fuel in hardened, dispersed dry-storage modules at the plant site. Adoption of such measures awaits a recognition by the NRC that commercial nuclear facilities can be considered as radiological weapons awaiting activation by an enemy.