Understanding the changing nuclear and mechanical characteristics of used nuclear fuel (UNF) over time and how these changing characteristics affect storage, transportation, and disposal options can require many tools and types of data. To streamline analysis capabilities for the waste management system, a comprehensive, integrated data and analysis tool has been assembled—UNF-Storage, Transportation & Disposal Analysis Resource and Data System (UNF-ST&DARDS).

The Electric Power Research Institute (EPRI) convened a workshop of over 40 representatives of the nuclear industry, federal government, national laboratories, and suppliers of used-fuel dry-storage systems to discuss the potential issues associated with extended dry storage of used fuel, that is, storage considerably beyond the term of current and recently proposed U.S. Nuclear Regulatory Commission (NRC) regulations. The workshop was held November 18-19, 2009, at EPRI's offices in Washington, DC.

The work reported here is an investigation of the sensitivity of component temperatures in a specific storage system, including fuel cladding temperatures, in response to modeling assumptions that differ from design-basis, including age-related changes that could degrade the thermal behavior of the system. Preliminary evaluations of representative horizontal and vertical storage systems at design basis conditions provides general insight into the expected behavior of storage systems over extended periods of time.