There is a question that comes up when the team at the Nuclear Waste Management Organization (NWMO) meets people across Northwestern Ontario: What is used nuclear fuel?
When asking us, many people say they picture yellow barrels, glowing goo, or green rods. The reality is much different.
Used nuclear fuel is solid ceramic pellet that is not flammable, explosive and not water soluble.
In Canada, used nuclear fuel from CANDU reactors (which generate about half of Ontario's electricity) is a stable, ceramic solid. Uranium ore is turned into uranium dioxide powder which is compressed and baked into ceramic pellets. These are stacked inside metal tubes which are welded together into a bundle. Each bundle is roughly the size and shape of a fireplace log.
If you were to handle a fuel bundle before it is placed into a CANDU reactor, it would be heavy – 53 lbs or 24 kgs – but not dangerous because your skin is enough of a barrier to protect you from the radiation. After 15 to 18 months in a reactor, the bundle has produced enough energy to power about 120 homes and it is no longer safe to handle because it is very radioactive.
This radioactivity requires careful, long-term management to protect people and the environment. For the short to medium term, the used fuel is stored in above-ground storage containers. This is safe, but since those containers have an operating span of approximately 100 years, they are not considered a long-term storage solution.
This is why almost every nation with a nuclear power program is in some phase of developing a deep geological repository for the safe long-term isolation and storage of used nuclear fuel. Finland is furthest along. They have built their deep geological repository, and it is expected to be operational this year.
In November 2024, NWMO announced they will be moving forward with the process to site a deep geological repository for used nuclear fuel in the area of Wabigoon Lake Ojibway Nation and the Township of Ignace in Northwestern Ontario.
Once people learn about used nuclear fuel, the next question the team often gets: So, if it’s highly radioactive, how can you be sure it will be safe in the repository?
A deep geological repository uses engineered and natural barriers to safely contain and isolate used fuel. Each barrier acts as part of the system but also provides a unique and stand-alone level of protection. If any of the barriers deteriorates, the next one comes into play to keep the used fuel safely contained and isolated.
You can learn more about the multiple barrier system and see pictures of what it is all about on the NWMO website.
So, the next time you see a misleading image of glowing goo, remember the reality: used nuclear fuel is a solid. It's a solid that has safely powered homes and businesses in Canada for more than half a century and it requires responsible, long-term care. Canada is among the leading countries in implementing a plan to keep people and the environment safe, essentially forever.
Providing accurate and easy-to-understand information is at the heart of what we do at the NWMO. As this project now advances into the regulatory decision-making process, there will be many more opportunities to ask questions and learn more.
If you have questions, please visit nwmo.ca, stop in to our Learn More Centres in Dryden and Ignace or email us at [email protected].
