Analysis of Section 19.2.3.5: Hydrology and Surface Water Quality
This article is part of a series exploring the views and perspectives of youth, artists and community members working with the Melgund Integrated Nuclear Impact Assessment Project. This initiative is a climate entrepreneurship and arts-based community recreation program, developed through community consultation, engagement participation in the integrated impact assessment process for the NWMO’s proposed Deep Geological Repository for nuclear waste fuel.
What is Proposed
In the Initial Project Description, the Nuclear Waste Management Organization (NWMO) outlines potential impacts on hydrology and surface water quality resulting from site clearing, blasting, construction, and effluent discharge. The proponent acknowledges that these activities could alter drainage, change hydrogeological regimes, and impact local waterbodies. To manage these risks, the proposal relies on a water management system, sediment controls, and adherence to regulatory guidelines. Despite acknowledging that site-specific water balance and quality modeling are currently incomplete, the proponent characterizes the residual risk to water systems as "low," citing confidence in standard industry mitigation practices.
Underlying Assumptions
Our review identified several key assumptions within the proponent’s risk assessment:
- Effectiveness of Standard Mitigation: The assessment assumes that general industry best practices will effectively mitigate site-specific hydrological risks without the support of completed local modeling.
- Acceptability of Mixing Zones: It is assumed that "regulated mixing zones"—areas where contaminants are diluted—are an acceptable method for meeting water quality guidelines, without detailing the spatial extent of these zones.
- Predictability of Risk: The document assumes a "low risk" determination can be confidently made prior to the completion of integrated site-wide water balance and water quality modeling.
- Climate Stability: There is an implicit assumption that standard mitigation measures will remain effective under future climate conditions, despite the lack of specific modeling for extreme weather events in this section.
Community Assessment
The primary concern arising from the community consultation is the speculative nature of the risk assessment. Because the integrated site-wide water balance and water quality modeling has not been completed, the "low risk" designation lacks the necessary data to be considered conclusive. Of particular concern is the reliance on "regulated mixing zones" for effluent discharge. Without specific spatial mapping, it is difficult to assess the potential for bioaccumulation of contaminants in these zones, which could have direct implications for fish health and traditional Indigenous harvesting practices.
Furthermore, the strategy of sharing technical results and site-specific mitigation measures only after modeling is complete limits the community’s ability to engage in the early design phase. This approach asks the community to accept a safety conclusion today based on evidence that will only be provided in the future.
Path Forward
To address these gaps, the following recommendations have been put forward:
- Prioritize Modeling: The proponent should prioritize the completion and public release of the integrated site-wide water balance and water quality modeling before the Impact Statement is finalized.
- Climate Resilience: Modeling must explicitly account for climate change variables, including increased frequency of extreme freshet events and prolonged drought, to validate that mitigation measures can withstand environmental stress.
- Define Mixing Zones: A detailed definition and spatial map of proposed "regulated mixing zones" must be provided to allow for a proper assessment of impacts on aquatic ecosystems.
- Contingency Planning: A robust adaptive management plan should be developed, outlining specific corrective actions if monitoring detects exceedances, ensuring short-term changes do not become long-term issues.
About the Integrated Assessment Process
The federal Impact Assessment Agency of Canada (IAAC) has formally launched the integrated impact assessment process for the proposed Deep Geological Repository (DGR) for Canada’s Used Nuclear Fuel Project, a major national infrastructure initiative led by the Nuclear Waste Management Organization (NWMO).
The proposed underground repository is designed to permanently contain and isolate used nuclear fuel in a secure geological formation. Wabigoon Lake Ojibway Nation and the Township of Ignace have been selected as host communities for the project. The site is located approximately 21 kilometres southeast of Wabigoon Lake Ojibway Nation and 43 kilometres northwest of Ignace, Ontario, near Highway 17.
According to project materials, the repository would provide permanent storage for approximately 5.9 million bundles of used nuclear fuel. The full lifecycle of the project is expected to span roughly 160 years, including site preparation, construction, operations, closure, and long-term monitoring.
Integrated Federal Review
Major nuclear projects in Canada are subject to an integrated assessment process jointly led by the Impact Assessment Agency of Canada and the Canadian Nuclear Safety Commission (CNSC). This “one project, one review” approach is intended to streamline regulatory oversight while ensuring rigorous evaluation of environmental, health, social, economic, and Indigenous rights impacts.
Under this framework, IAAC oversees the impact assessment requirements under the Impact Assessment Act, while the CNSC regulates nuclear safety under the Nuclear Safety and Control Act. The CNSC will issue the initial site preparation licence and manage all subsequent nuclear licensing for the project’s duration.
The integrated assessment also includes a focus on potential impacts on Indigenous Peoples, including rights, land use, cultural practices, health, and socio-economic conditions. Where potential adverse effects are identified, the process is intended to identify mitigation measures to reduce or avoid harm.
Public Comment Period Now Open
The first public comment period for the project is currently open and will run until February 4, 2026. During this phase, the public is invited to provide feedback on the Summary of the Initial Project Description submitted by the NWMO. Submissions received during this period will inform IAAC’s summary of issues, which will guide the next stages of the impact assessment. All comments submitted become part of the public project record and are posted to the federal Impact Assessment Registry.
This plain-language summary is provided by ECO-STAR North and Art Borups Corners to support public engagement.
Disclaimer: The views and perspectives expressed in this article are solely those of the independent arts program led by ECO-STAR North and Art Borups Corners. They do not reflect the official positions of the Nuclear Waste Management Organization (NWMO) or the Government of Canada.
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