One of the biggest questions surrounding the introduction of Small Modular Reactors (SMRs) is how nuclear waste will be managed. With three distinct types of waste—low-level, intermediate-level, and high-level—SaskPower is exploring various strategies to ensure safe and effective disposal.

Low-level waste makes up 90 percent of nuclear waste. It includes personal protective equipment, coveralls, work gloves, mop heads, and other items that could be contaminated.

"Radiation itself is pretty easy to measure in really small amounts, so one of the big things we’ll want to do is make sure we’re not cross-contaminating anything," said Travis Sandeski, a representative with SaskPower.

He said strategies to reduce volume are very important. Waste management strategies from other provinces will be considered. New Brunswick, for example, incinerates nuclear waste explained Sandeski.

“It goes to an external facility and helps them deal with that volume, so they get back the ash, and it’s still radioactive, but it’s condensed into a hockey puck of ash instead of all these coveralls.”

“When this strategy is used, the waste is isolated, put behind shielding, and will eventually decay. ‘Over time, you just have waste, not radioactive nuclear waste." 

Intermediate-level waste is generally mechanical and makes up seven percent of nuclear waste.

"A pump, a filter, or pipe that's exposed year over year. It’s not low-level waste, and it’s not your used fuel. It’s in that middle category and is treated accordingly."

High-level waste is the used fuel, which makes up just three percent of nuclear waste.

Nuclear waste is a solid around the size of a quarter. Fewer than 10 pellets a year are used to power one Canadian home each year.

The selected SMR would need to be refuelled bi-annually. During this time, the machine is shut down for maintenance and refueled.

"When it comes out of your reactor, it comes out hot in terms of how radioactive it is and how hot it is in terms of temperature."

The fuel will then be put in wet storage, where it will stay for a number of years until it’s cool enough to be placed in dry storage.

"These bundles are cool enough that you can stack a whole bunch together. They’re not generating a lot of heat. They put this shielding around them. It’s surrounded by steel and concrete, and that shields the radiation," said Sandeski. 

In the future, Canada plans to have all high and intermediate-level waste sent to the Nuclear Waste Management Organization’s (NWMO) Deep Geological Repository (DGR). The site selection for the DGR is underway and expected to be announced later this year. 

Sandeski emphasized that there will be several barriers around the waste, so if one barrier were to fail, there would be additional barriers in play. He noted that the sites will be in a geographical area where it would take around a million years for water to interact with the fuel, and by that time, it will no longer be radioactive.