Questions and Answers about Irradiated Nuclear Fuel in Canada

A new document by Gordon Edwards on issues surrounding the handling of Irradiated Nuclear Fuel in Canada is now available on-line: see 

The document is based on Q&A following a presentation by Gordon to the South Bruce NWMO Citizens’ Liaison Committee (CLC) on November 5, 2020, entitled “Nuclear Fuel Waste – Before the Burial”.

NWMO is the Nuclear Waste Management Organization. It is owned by the three electrical utility companies that have operated CANDU power reactors in Canada.  They are the owners of all the used CANDU nuclear fuel. 

NWMO has been authorized by an Act of Parliament to seek a “willing host community”  to receive all of Canada’s irradiated nuclear fuel for burial in a Deep Geological Repository (DGR). The South Bruce municipality is one of the candidates.

The Executive Summary of the report is reproduced below –


Executive Summary:

On November 5, 2020, I gave an invited zoom presentation to the South Bruce NWMO Community Liaison Committee (CLC) dealing with the hazards of Irradiated Nuclear Fuel prior to burial. 

See the video recording:

The South Bruce Municipality, located about 40 kilometres east of Lake Huron, is one of two remaining candidates – out of an initial field of 22 communities, 3 of them in Saskatchewan and the rest in Ontario – from which a willing host community is to be chosen to receive all of Canada’s used nuclear fuel for burial.  The other remaining candidate is Ignace, located northwest of Lake Superior on the road to Winnipeg.

Following my presentation, I was asked by the CLC to prepare written answers to a series of wide-ranging questions, some from the committee members (oral) and some from viewers of the zoom session (written).

The following document is a list of 17 questions with answers. I have included 5 pages of background information because the questioners were not always aware of all the basic facts about irradiated nuclear fuel or about the concept of Rolling Stewardship, an alternative strategy for managing nuclear wastes without abandoning them.

Some of the important insights included in this text are the following:

(1)  the used fuel bundles from CANDU nuclear reactors are not themselves the radioactive wastes but merely the containers of the actual radioactive wastes, the hundreds of radioactive materials that are created inside the reactor as a result of the nuclear fission process and trapped in the used fuel;

(2)  the radioactive waste materials contained in used nuclear fuel are extremely diverse in their physical, chemical and biomedical properties, each one having its own unique pathways through the environment and through the human body;

(3)  used nuclear fuel rods that are damaged will release radioactive materials in the form of gases, vapours, aerosols and particulates, which are then disseminated throughout the primary cooling system of a nuclear reactor and inside the hot cells that must be used to repackage the used fuel before burial;

(4)   because radioactivity is a form of nuclear energy that cannot be shut off by any method known to science, heat is generated spontaneously by the nuclear wastes in used fuel and will force the temperature of surrounding materials to increase for many thousands of years after removal from the reactor;

(5)  used nuclear fuel needs to be cooled for decades – typically 30 years or more – before it can be sealed in an underground repository and then it will heat up the surrounding rocks which will not return to ambient temperatures for 50,000 years;

(6)  Rolling Stewardship is not proposed as a solution to the nuclear waste problem but as a responsible management scheme motivated by the realization that at present there is no proven safe solution to this problem.