Managing Aging Effects on Dry Cask Storage Systems for Extended Long-Term Storage and Transportation of Used Fuel (Rev. 2)
At present, the United States does not have a designated disposal site for used nuclear fuel — the nation therefore faces the prospect of extended long‐term storage (i.e., >60 years) and deferred transportation of used fuel at operating and decommissioned nuclear power plant sites. Under current U.S. federal regulations contained in Title 10 of the Code of Federal Regulations (CFR) 72.42, the initial license term for an Independent Spent Fuel Storage Installation (ISFSI) must not exceed 40 years from the date of issuance (20 years before the rule change in 2010 that became effective in 2011). The U.S. Nuclear Regulatory Commission (NRC) may renew licenses at the expiration of the license term upon application by the licensee for a period not to exceed 40 years. Applications for ISFSI license renewals must include the following: 1. Time‐limited aging analyses (TLAAs) that demonstrate that structures, systems, and components (SSCs) important to safety will continue to perform their intended function for the requested period of extended operation and 2. A description of the aging management program (AMP) for the management of issues associated with aging that could adversely affect SSCs important to safety. In addition, the application must include design basis information as documented in the most recently updated final safety analysis report, as required by 10 CFR 72.70. Information contained in previous applications, statements, or reports filed with the Commission under the license may be incorporated by reference, provided that these references are clear and specific. The NRC has issued the “Standard Review Plan for Renewal of Spent Fuel Dry Cask Storage System Licenses and Certificates of Compliance,” NUREG‐1927, under which NRC may renew a specific license or a Certificate of Compliance (CoC) for a term not to exceed 40 years. Both the license and the CoC renewal applications must contain revised technical requirements and operating conditions (fuel storage, surveillance and maintenance, and other requirements) for the ISFSI and dry cask storage system (DCSS) that address aging effects that could affect the safe storage of the used fuel. The information contained in the license and CoC renewal applications will require NRC review to verify that the aging effects on the SSCs in DCSSs/ISFSIs are adequately managed for the requested period of extended operation. To date, all of the ISFSIs across the United States with more than 1,500 dry casks loaded with used fuel have initial license terms of 20 years — three ISFSIs (Surry, H.B. Robinson, and Oconee) have received their renewed licenses for 40 years, and two other ISFSIs (Calvert Cliffs and Prairie Island) have applied for license renewal for 40 years. In addition, renewal of the CoC for the VSC‐24 system is pending approval from NRC.