Most of the commercial reactor spent nuclear fuel destined for disposal in the potential Yucca Mountain repository consists of irradiated uranium-dioxide fuel pellets sealed in zirconium-alloy cladding. The cladding integrity is important if it is to be regarded as a barrier against the release of radionuclides to the environment. Recent data from the Yucca Mountain site characterization suggests that the waste container may eventually be exposed to larger volumes of water containing halides and other impurities than previously expected. In addition, it is expected that the concentration of halides and other impurities may increase due to evaporation. Thus, the possibility of localized corrosion of zirconium- alloy cladding in contaminated water has been evaluated based on available corrosion information for zirconium and its alloys.
Keywords: zirconium and its alloys, halides, localized corrosion, repository.