A group of NWMO scientists recently published an article in the prestigious international peer-reviewed journal, Progress in Materials Science ,that reviews decades of work in corrosion to support the safety of the NWMO copper-coated used fuel container. The article, which can be accessed here, explains how the containers will withstand corrosion processes for more than one million years.
According to Dr. Peter Keech, Manager of Engineered Barrier Science at the NWMO and the article’s senior author:
“This paper shows that we can reasonably expect about 0.25 of a millimetre of corrosion to occur over a million years. Even if you conservatively presume a series of unlikely events, the total damage will be less than 1.25 millimetres. When we consider that the reference thickness of the copper coating is three millimetres, it is clear that we can depend on the container to safely isolate the used nuclear fuel from people and the environment, as part of a multiple barrier system, even as we account for corrosion.”
This work builds on the expertise and knowledge that NWMO has incorporated into its work. In 2014, NWMO refined its container design to one that is optimized for the used CANDU fuel produced by Canadian nuclear power reactors and since then the NWMO’s research program and container design have continued to advance.
The NWMO’s used fuel containers are engineered to remain intact and keep the used nuclear fuel completely isolated until the fuel’s radioactivity has decreased to levels of natural uranium. The container prevents radionuclides in the fuel from escaping into the underground environment and is able to withstand pressures of the overlying rock and loading from three-kilometre-thick glaciers during a future ice age.