The proposed storage facility is called a “deep geological repository” (DGR) and would sit 500 to 800 meters underground in one of two Ontario sites. Every room storing nuclear waste will be packed and sealed with bentonite clay, as it helps dissipate heat and reduces water movement when packed tightly.
But the clay is mined from a natural deposit in Wyoming and will inevitably arrive embedded with tiny bits of organic matter. Microbes will also be in the clay and rock surrounding the facility, and in groundwater that may pass through it.
According to Myrna Simpson, one of the researchers involved in the study, some of that microbial life may produce sulphide, a chemical compound that could lead to corrosion of the metal containers holding the used fuel.
To test if the microbes can grow, the group building Canada’s DGR, the Nuclear Waste Management Organization (NWMO), brought together Simpson and professors Josh Neufeld and…
