Agency warns high-level nuke waste casks deteriorating, already

Nuclear waste storage casks for irradiated reactor fuel assemblies from two Pennsylvania nuclear power plants are showing signs of “premature degradation” after just a few years of storage of the timeless hazard. The Nuclear Regulatory Commission (Information Notice 2013-07) is cautioning operators of all nuclear power plants with the on-site dry cask storage systems that these hazardous material storage canisters are showing signs of deterioration. from “environmental moisture.”  At the Peach Bottom nuclear power plant, water has caused the corrosion of an O-ring seal on the lid of one of the nuclear waste storage casks allowing some of the helium coolant to leak out.  Not good, particularly because this cask was only 10 years old when a low pressure alarm sounded and its supposed to be licensable for up to 100 years. Meanwhile, a nuke waste cask from Three Mile Island Unit 2, the unit that had the nuclear accident in 1979, what fuel didn’t melt was put into dry casks for storage and shipped out to Idaho National Energy Laboratory. Seasonal freezing and ice has caused cracks to form in the concrete outer structure of one of the casks potentially shortening its projected 50 year service life.

Given that the nuclear waste is going to be extremely hazardous for millions of years, the "quality" of these casks suggests that this system is going to fail much sooner than currently credited.