Performance Assessment of a Post-Closure Pyrophoric Event

The U.S. Department of Energy (DOE) spent nuclear fuel (DSNF) is categorized into eleven different spent fuel groups. Group 7, is predominantly uranium metal spent fuel from N Reactor that could oxidize rapidly in the presence of air when a waste package is breached. Such rapid oxidation constitutes a pyrophoric event. The consequences of a post closure pyrophoric event were evaluated in terms of its potential to damage adjacent waste packages and consequences of it in terms of long-term dose to humans. This work was conducted as part of the total system performance assessment (TSPA) of DOE spent fuel for the National Spent Nuclear Fuel Program. These analyses were performed in support of the site recommendation for a repository at Yucca Mountain, Nevada