RADIOACTIVE WASTE IN CANADA
In Canada, radioactive waste is generated during various stages of the nuclear fuel cycle, including uranium mining and processing, nuclear fuel fabrication, nuclear reactor operations, research and development activities, radioisotope manufacture and use, and decommissioning activities.
Canada’s waste classification system recognizes four main classes of radioactive waste:
- High-level radioactive waste;
- Intermediate-level radioactive waste;
- Low-level radioactive waste; and,
- Uranium mine and mill waste.
Canada’s approach to radioactive waste management is founded upon the Government of Canada’s 1996 Policy Framework for Radioactive Waste. The Policy Framework provides a national context for radioactive waste management and a set of principles governing institutional and financial arrangements to ensure that the management of radioactive waste is carried out in a safe, environmentally sound, comprehensive, cost-effective and integrated manner. The Policy Framework states that the federal government has the responsibility to develop policy, regulate, and oversee owners to ensure that they comply with legal requirements and meet their funding and operational responsibilities in accordance with approved waste management plans. Natural Resources Canada is the lead Department responsible for federal radioactive waste policy matters.
Waste owners are responsible for funding and managing their waste, in accordance with the “polluter pays” principle, and are required to develop approaches for managing their waste (short-term and long-term), individually or in cooperation with others waste owners. Those approaches are subject to regulatory review by Canada’s regulator, the Canadian Nuclear Safety Commission (CNSC).
The Policy Framework clearly recognizes that arrangements may be different for the different waste categories: uranium mine and mill waste, low- and intermediate-level radioactive waste, and high-level waste or nuclear fuel waste.
The Nuclear Safety and Control Act (NSCA), the Nuclear Fuel Waste Act (NFWA), the Nuclear Liability and Compensation Act (NLCA), and the Nuclear Energy Act (NEA) are the main components of Canada’s legislative and regulatory framework for nuclear matters.
The NSCA, which was passed by Parliament in 1997, is the key piece of legislation that governs the safety of the nuclear industry and radioactive waste management in Canada. The NSCA provides legislative authority for the regulation of Canada’s nuclear sector and established the CNSC as Canada’s independent federal nuclear regulator. In the area of radioactive waste, the CNSC regulates and monitors Canada’s radioactive waste management facilities to ensure they are operated safely; it imposes rigorous reporting requirements on operators of radioactive waste management facilities, and it verifies that facilities comply with established safety requirements through inspections and audits. The CNSC’s regulatory decision-making process is fully independent from the Government of Canada. In addition, the nuclear industry is subject to the provincial and territorial acts and regulations where nuclear-related activities are carried out. Where there is an overlap of jurisdictions and responsibilities, the CNSC takes the lead in harmonizing regulatory activities including the formation of joint regulatory groups involving provincial and territorial regulators.
The Canadian regulatory approach to the safety of nuclear fuel waste and radioactive waste management is based on three principles:
- lifecycle responsibility and licensing
- defence in-depth
- multiple barriers
The CNSC sets the standards and conditions; it is then the responsibility of the person in possession of the associated nuclear substance, or the operator of the associated facility, to ensure safety. For example, in the context of radioactive waste management, it is the licensee’s responsibility to demonstrate to the satisfaction of the regulatory body that a nuclear fuel or radioactive waste management facility can and will be operated safely throughout the lifetime of the facility. The regulatory regime is flexible about how licensees comply with regulatory requirements. The licensee must demonstrate how the facility design meets all applicable performance standards and will continue to do so throughout its design life.
In addition to the powers and responsibilities outlined above, the NSCA authorizes the Commission to require that operators of nuclear facilities provide financial guarantees as a condition of their licence. This is a discretionary power that the Commission has used to require operators of uranium mines and mills, uranium refineries and fuel fabrication facilities, nuclear power plants and research reactors and facilities to provide financial guarantees to support decommissioning activities and the long-term management of radioactive waste. The financial guarantees are based on decommissioning plans accepted by the CNSC, using conservative cost estimates for implementing those plans. Financial guarantees ensure that the costs of decommissioning will be borne by the licensees, not the taxpayers.
In the case of nuclear fuel waste, the Government of Canada passed the NFWA in 2002 to ensure a national plan is developed and implemented for the long-term management of nuclear fuel waste. It also requires waste owners to set aside, in segregated trusts, sufficient funding to pay for the full lifecycle cost of implementing the Government-selected, long-term management plan for nuclear fuel waste. Pursuant to the NFWA, it is the owners of the waste, through the Nuclear Waste Management Organization (NWMO), that are responsible for defining an approach for long-term waste management, providing funding and, following Government acceptance, implementing the approach with ongoing Government oversight.
Canadian methods for the management of radioactive waste are similar to those of other countries. Significant emphasis is placed on minimization, volume reduction, conditioning and interim storage of the waste, since long-term management facilities are not yet available. Radioactive waste is stored onsite or offsite, in above- or below-ground engineered structures. Some of the waste may be reduced in volume by compaction or incineration prior to storage. Wastes may be processed on-site or may be shipped to a commercial processing facility (mainly in the United States) for treatment. In such cases, the treated waste is returned to Canada for storage. All radioactive waste currently generated is stored in such a way that it can be easily retrieved when necessary. Operators have instituted methods to recover storage space after sufficient radioactive decay has occurred, or reclaiming existing storage space through further compaction (super compaction), segregation or both.
As is the case for all nuclear activities, the facilities for handling radioactive waste must be licensed by the CNSC and conform to all pertinent regulations and licence conditions. The waste management objective throughout the industry – from mines to reactors – is the same: to protect people and to control and limit the release of potentially harmful substances into the environment.
Certain types of radioactive waste, such as from hospitals, contain only small amounts of radioactive materials, with short half-lives. This means that radioactivity decays within hours or days. After holding the waste until the radioactivity has decayed to the acceptable levels authorized by the CNSC, the waste can be disposed of by conventional means (in local landfill or sewer systems).
Atomic Energy of Canada Limited (AECL), a Crown Corporation wholly owned by the Government of Canada, is responsible for the federal government’s radioactive waste and decommissioning obligations at AECL and other sites across Canada. AECL oversees its contractor, Canadian Nuclear Laboratories (CNL), which operates Canada’s nuclear laboratories, and implements programs and projects to manage federal radioactive waste responsibilities. CNL operates a commercial waste service for small producers and owners of radioactive waste, such as hospitals and universities. CNL accepts, on a fee-for-service basis, low- and intermediate-level radioactive waste (L&ILRW) from these organizations for long-term management.
In Canada, all high-level waste is nuclear fuel waste from nuclear power and research reactors. Nuclear fuel waste is stored in wet and dry states at the locations where it is produced. When the fuel is first discharged from a power reactor, it is placed in water-filled bays. Water cools the fuel and shields the radiation. After several years in the bays – typically seven to ten years, depending on site-specific needs and organizational administrative controls – when the associated heat generation has diminished, the nuclear fuel waste can be transferred to an onsite dry storage facility. These dry storage facilities consist of large, reinforced concrete cylinders or containers.
A Canada Deuterium Uranium (CANDU) fuel bundle is approximately 100 mm in diameter by 500 millimetres long, with a total mass of about 25 kg (including about 20 kg of uranium). Each nuclear power plant in Canada has enough storage space to store all the nuclear fuel waste produced during the operating life of the station. A typical 600-megawatt CANDU nuclear reactor produces approximately 90 tonnes of heavy metal nuclear fuel waste annually. Three designs of dry storage containers are used in Canada for CANDU fuel bundles: concrete silos, AECL Modular Air-Cooled Storage (MACSTOR), and Ontario Power Generation (OPG) dry storage containers.
As of December 31, 2013, the total inventory of nuclear fuel waste in Canada was about 10,000 m3. OPG owns the majority (87%) of Canada’s nuclear fuel waste, and the other power utilities, namely, New Brunswick Power and Hydro-Québec are responsible for 5% each. AECL has a small amount of waste from its prototype and research reactors, which accounts for the remaining 3%. Other waste owners, e.g. universities, produce a very small quantity of nuclear fuel waste.
The fuel cycle in Canada is a once-through process. Currently, there is no reprocessing or intent to reprocess nuclear fuel waste for recycling of its uranium and plutonium content.
Nuclear Fuel Waste Management
In 2005, the NWMO recommended, to the Government of Canada, the Adaptive Phased Management (APM) approach for the long-term management of nuclear fuel waste. The APM approach involves centralized containment and isolation of nuclear fuel waste in a deep geologic repository (DGR) in a suitable rock formation, located at a site in an informed and willing host community. A key element of the APM approach is that it is sufficiently flexible to adjust to changing social and emerging technological developments. In 2007, the Government of Canada selected the APM approach as Canada’s plan for the long-term management of nuclear fuel waste, and directed the NWMO to move forward on implementation of the plan.
Through public dialogue and consultation, the NWMO developed a site selection process aimed at identifying a willing and informed community with a suitable site to host a DGR for the long-term management of nuclear fuel waste. This voluntary site selection process was initiated in 2010 and by 2012, twenty-two communities in Ontario and Saskatchewan came forward to participate in the process and learn more about the APM project. Study areas have been narrowed through assessments, and as of December 2015, the NWMO had focused its siting process on nine Ontario communities. Those nine communities are continuing to engage with the NWMO and explore the possibility of hosting a DGR and Centre of Expertise for the long-term management of nuclear fuel waste.
The NWMO is also advancing work on the development of repository designs and safety cases, and governance and capacity building to provide the necessary skills, expertise, and capabilities required to implement APM.
Further information about the implementation of the government-selected plan is available on the NWMO’s website at www.nwmo.ca
Canadian waste owners make use of a variety of above-ground and in-ground storage structures and facilities to store low-level and intermediate-level radioactive waste (L&ILRW). All structures and facilities that receive waste on an on-going basis provide for complete containment of the L&ILRW, and prevent the release of contaminants to the environment.
Ontario Power Generation (OPG), Canada’s largest nuclear utility, has a centralized storage facility for L&ILRW at the Bruce Nuclear Site, whereas other waste owners generally store their L&ILRW at the site where the waste was generated. OPG and AECL collectively own 97% of Canada’s 665,500 m3 of L&ILRW, and AECL is responsible for a further 1.7 million m3 of historic low-level radioactive waste (LLRW). Historic LLRW consists largely of radium and uranium contaminated soils. It has resulted mainly from the transportation and processing of uranium ores prior to the establishment of a regulatory regime for radioactive wastes. Both organizations have initiatives underway to establish long-term waste management facilities at their sites for L&ILRW, and AECL’s contractor, CNL is implementing the Port Hope Area Initiative, which will address the bulk of Canada’s inventory of historic waste.
In the case of OPG, it has proposed the construction and operation of a DGR for the long-term management of its L&ILRW on lands adjacent to the current Western Waste Management Facility at the Bruce Nuclear Site. The DGR Project is currently undergoing regulatory review and additional information can be found on OPG’s website:
To address federal radioactive waste and decommissioning responsibilities at AECL sites, CNL is proposing to construct a near-surface disposal facility at Chalk River Laboratories. The CNSC initiated the environmental assessment for the project in May 2016, and CNL is aiming to receive the required approvals and construct the facility so that it can begin operation in 2020. The facility will permit CNL to decommission more than 100 buildings and structures at Chalk River Laboratories that are outdated and no longer needed, and remediate lands contaminated by past practices. CNL also plans to complete the Port Hope Area Initiative by 2023, which will see the cleanup of historic contamination in the Port Hope, Ontario area, and the consolidation of the waste in two engineered long-term waste management facilities.
Uranium mining produces both clean waste rock and mineralized waste rock. Clean waste rock is placed in surface rock piles for future use. Mineralized waste rock contains low concentrations of radionuclides and/or heavy metals, and is usually found close to the ore body. This rock needs to be managed so that contaminants are not released to the environment.
The milling of uranium ore produces tailings and waste water. Tailings are stored in tailings management facilities designed to isolate the tailings from the surrounding environment. The currently operating uranium mills in Canada use mined-out open pits to contain the tailings. This method isolates the tailings from groundwater and surface water flow to prevent contamination of the environment over the long term. Water used in the milling process is recycled as much as possible. Waste water is treated before being discharged to the environment so that the radionuclides and trace metals are reduced to acceptable levels.
All currently active uranium mining sites in Canada are situated in northern Saskatchewan. However, Elliot Lake, Ontario was the major uranium mining centre in Canada for over 40 years. Since the last Elliot Lake mining facility closed in 1996, uranium mining companies have committed well over $75 million to decommission all mines, mills, and waste management areas. Water treatment and minor engineering works continue to be the main activities at these locations. Water quality within the area watershed has improved dramatically since the closure and decommissioning of the mines, and currently meets Ontario Drinking Water Standards.
Further information on the management of radioactive waste in Canada can be found in Canada’s Fifth National Report for the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management at the following link:http://www.nuclearsafety.gc.ca/eng/resources/publications/reports/jointconvention/