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Ontario Tech acknowledges the lands and people of the Mississaugas of Scugog Island First Nation.

We are thankful to be welcome on these lands in friendship. The lands we are situated on are covered by the Williams Treaties and are the traditional territory of the Mississaugas, a branch of the greater Anishinaabeg Nation, including Algonquin, Ojibway, Odawa and Pottawatomi. These lands remain home to many Indigenous nations and peoples.

We acknowledge this land out of respect for the Indigenous nations who have cared for Turtle Island, also called North America, from before the arrival of settler peoples until this day. Most importantly, we acknowledge that the history of these lands has been tainted by poor treatment and a lack of friendship with the First Nations who call them home.

This history is something we are all affected by because we are all treaty people in Canada. We all have a shared history to reflect on, and each of us is affected by this history in different ways. Our past defines our present, but if we move forward as friends and allies, then it does not have to define our future.

Learn more about Indigenous Education and Cultural Services

What is a Subcritical Assembly?

A subcritical assembly is a type of nuclear reactor, but on the opposite end of the spectrum from a larger reactor, such as the current ones used by Ontario Power Generation (OPG) or Bruce Power.

The proposed subcritical assembly will be the only facility of its kind in Canada. 


A subcritical assembly is based on the same principles of nuclear science as larger reactors, but vastly different in its operation in that it cannot generate power or electricity.  The table shows how the subcritical assembly compares to other reactors in Canada.

The subcritical assembly has many distinct design characteristics that makes it very conducive for research, training, and teaching purposes; and is why it is often called a “teaching reactor.” 

In Canada it is referred to as a subcritical assembly and that it is what the Canadian Nuclear Safety Commission, our regulatory body, refers to it as.  It is acknowledged that other areas of the world also refer to it as a subcritical reactor.

Types of Reactors In Canada. OPG and Bruce CANDU Power Reactors are on the high end of the spectrum at over 600 MW.  Towards the opposite end of the spectrum we have the Research Reactors at McMaster, Ecole Polytechnique, Royal Military College, and Canadian Nuclear Laboratories.  These range from 5 megawatts to 0.0001 megawatts.  The proposed subcritical assembly is on the low end at 0 megawatts of power.
Check out our FAQ sect...
Check out our FAQ section for a more detailed description of what is a subcritical assembly
Subcritical Assemblies...
Subcritical Assemblies Around the World