DRY CASK STORAGE AND COMPARATIVE RISKS
This chapter addresses the second and third charges of the committee’s statement of task:
The safety and security advantages, if any, of dry cask storage1 versus wet pool storage at reactor sites.
Potential safety and security advantages, if any, of dry cask storage using various single-, dual-, or multi-purpose cask designs.
The second charge calls for a comparative analysis of dry cask storage versus pool storage, whereas the third charge focuses exclusively on dry casks. The committee will address the third charge first to provide the basis for the comparative analysis.
By the late 1970s, the need for alternatives to spent fuel pool storage was becoming obvious to both commercial nuclear power plant operators and the Nuclear Regulatory Commission. The U.S. government made a policy decision at that time not to support commercial reprocessing of spent nuclear fuel (see Appendix D). At the same time, efforts to open an underground repository for permanent disposal of commercial spent fuel were proving to be more difficult and time consuming than originally anticipated.2 Commercial nuclear power plant operators had no place to ship their growing inventories of spent fuel and were running out of pool storage space.
Dry cask storage was developed to meet the need for expanded onsite storage of spent fuel at commercial nuclear power plants. The first dry cask storage facility in the United States was opened in 1986 at the Surry Nuclear Power Plant in Virginia. Such facilities are now in operation at 28 operating and decommissioned nuclear power plants. In 2000, the nuclear power industry projected that up to three or four plants per year would run out of needed storage space in their pools without additional interim storage capacity.
This chapter is organized into the following sections:
Background on dry cask storage.
Evaluation of potential risks of dry cask storage.
Potential advantages of dry storage over wet storage.
Findings and recommendations.