What is Radioactive Waste?

What Is Radioactive Waste?

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What is Radioactive Waste?

This infographic features the definition of radioactive waste and describes different aspects of its four classifications

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Radioactive waste is any liquid, gas or solid that contains a radioactive nuclear substance and which has been declared to be waste.

Facilities that contain radioactive waste are monitored and regulated by the CNSC.

Any industry that uses or produces radioactive materials is licensed and regularly inspected by the CNSC.

What makes radioactive waste different?

Radioactivity naturally decays over time but has to be contained and isolated for a sufficient period of time until it no longer poses a risk to the health and safety of humans and the environment.

This period of time varies depending on the type of waste and radioactive material.

There are four classes of radioactive waste in Canada

Classes of radioactive waste are organized according to the containment and isolation required to ensure safety in the short and long term and take into consideration the risk to the health and safety of humans and the environment.

Uranium mine and mill waste

 
Definition

Includes tailings and waste rock, generated by the mining and milling of uranium ore.

Where does it come from?

From mining or from milling ore into yellowcake.

What does it look like?

Tailings have the consistency of fine sand. Waste rock looks like blasted boulders and gravel.

How is it stored in the interim?

Tailings are placed back into the mined-out pit or tailing containment facilities. Waste rock is stored in piles on the surface.

Who monitors it?

CNSC inspectors monitor mine sites during operation and long after closure.

How long will it be radioactive?

Because the decay of natural uranium is so slow, it can take billions of years to reach the earth’s normal background level of radiation.

Low-level radioactive waste

 
Definition

Is more radioactive than clearance levels and exemption quantities allow.

Where does it come from?

Nuclear power plants, research reactors, test facilities, radioisotope manufacturers or users, uranium refining and conversion, and nuclear fuel fabrication.

What does it look like?

Used equipment, paper, cable, clothing, decommissioned parts, even mops.

How is it stored in the interim?

Typically, long-lived low-level waste is stored above ground at licensed facilities in bins and bags, and may be incinerated to reduce the volume.

Who monitors it?

Low-level waste is monitored at licensed facilities that are inspected by the CNSC.

How long will it be radioactive?

Some short-lived waste can decay within hours or days and then be disposed of like regular waste. Longer-lived waste may need isolation for up to a few hundred years.

Intermediate-level radioactive waste

 
Definition

Contains enough longlived radionuclides to require isolation and containment.

Where does it come from?

Nuclear power plants, prototype and research reactors, test facilities, and radioisotope manufacturers and users.

What does it look like?

Refurbishment waste, ion-exchange resins and some radioactive sources used in radiation therapy.

How is it stored in the interim?

Currently, this waste is stored in shielded above-ground or inground storage silos at licensed waste facilities.

Who monitors it?

The CNSC inspects and licenses all intermediate waste management facilities.

How long will it be radioactive?

This waste generally contains long-lived radionuclides that require isolation beyond several hundred years (e.g., 300 to 500 years, or 15 to 25 generations).

High-level radioactive waste

 
Definition

Primarily used nuclear fuel, along with small amounts of waste that generate significant heat.

Where does it come from?

Nuclear power plants, prototype and research reactors, and test facilities.

What does it look like?

This is used nuclear fuel that is still significantly radioactive.

How is it stored in the interim?

Used fuel is stored at the reactor site in reinforced, leak-proof cooling pools for 7 to 10 years, and then can be transferred to dry storage in concrete canisters or silos.

Who monitors it?

The CNSC and the International Atomic Energy Agency (IAEA) monitor used nuclear fuel.

How long will it be radioactive?

The radioactivity of irradiated, used nuclear fuel starts high but decreases quickly (by 99% in the first 10 years). It then takes about 1 million years to decrease to the original level of natural uranium.

The CNSC ensures safe radioactive waste management.