Reviewing Section 19.2.3.6: Topography, Soils, and Sediment
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
The Nuclear Waste Management Organization (NWMO) has outlined its assessment of how the proposed Deep Geological Repository (DGR) will affect the physical landscape, specifically topography, soils, and sediment. As detailed in the Initial Project Description, project activities such as site clearing, blasting, and the discharge of treated effluent are identified as primary drivers of change. The proponent asserts that through the implementation of standard mitigation measures—such as sediment control and minimizing vegetation clearing—residual effects on topography will be effectively eliminated. Furthermore, the NWMO claims that while some changes to soil and sediment quality may occur due to dust or effluent, these will be localized and remain within a low-risk profile.
Underlying Assumptions
Our review of the technical documentation identified several key assumptions that support the proponent’s conclusion of ‘low risk’:
- Mitigation Reliability: It is assumed that standard industry mitigation strategies will be fully effective in preventing significant impacts, despite the scale of the proposed blasting and excavation.
- Landscape Uniformity: The assessment assumes that because the site is ‘typical of the Canadian Shield,’ there are no unique topographical features requiring specific protection or detailed study.
- Data Applicability: The document assumes that risk screenings presented in Table 19.11 apply to soils and sediment, despite the table being explicitly titled ‘Surface Water Quality.’
- Natural Variability: The assessment relies on the assumption that contaminant levels will remain within ‘natural variability’ without defining the quantitative baseline for that variability.
Community Assessment
Through our community-driven review process, we have identified specific concerns regarding the clarity and accuracy of the data presented. A significant technical discrepancy was noted where Table 19.11 is titled regarding ‘Surface Water Quality,’ yet it is presented as the conclusion for the topography, soils, and sediment section. This mislabeling creates confusion about which data actually supports the risk conclusion. Furthermore, the dismissal of topographical significance based on regional ‘typicality’ is concerning to local stakeholders; relying on broad generalizations may overlook site-specific features that hold ecological or cultural value. Finally, the reliance on undefined ‘natural variability’ to assess sediment contamination creates a subjective standard that could mask localized impacts, making it difficult for the community to verify safety claims.
Path Forward
To ensure a transparent and rigorous assessment, we recommend the proponent provide a detailed technical appendix substantiating the claim that proposed mitigation measures are proven effective specifically for DGR-scale excavation. It is imperative that the labeling and content of Table 19.11 be corrected to ensure accurate correlation with soil and sediment metrics. Additionally, we call for the establishment of clear, quantitative thresholds for ‘natural variability’ prior to future modeling phases. This will provide the Impact Assessment Agency of Canada and local communities with an objective framework for monitoring potential contamination.
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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