Analyzing Rock Stability and Environmental Risks at Revell
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 NWMO is conducting geochemical testing of rock core samples at the Revell site to evaluate the potential for acid rock drainage (ARD) and metal leaching (ML). The proponent claims that the bedrock is 95 percent granodiorite-tonalite, which they describe as having low porosity and minimal sulfur-bearing minerals. They assert that these characteristics will support radionuclide retardation and ensure the durability of the engineered barrier system. Preliminary findings suggest the rock is non-acid generating and non-toxic, which the proponent expects will support the safety case for the Initial Project Description.
Underlying Assumptions
- The six boreholes drilled to date provide a statistically significant representation of the entire repository site.
- Lithological homogeneity observed in initial samples will remain consistent across the total volume of excavated rock.
- Kinetic testing, though currently incomplete, will inevitably confirm preliminary non-acid generating findings.
- Matrix porosity is the primary factor in radionuclide movement, rather than secondary fracture networks.
Community Assessment
Our review highlights several critical concerns regarding the proponent’s methodology. First, the characterization of the site relies on a very small sample size—only six boreholes and 100 core samples—which may miss localized geochemical hazards that could affect water quality. Furthermore, the proponent makes definitive safety statements while kinetic testing is still underway, potentially underestimating long-term metal leaching risks. There is also a heavy reliance on internal NWMO documents rather than independent, peer-reviewed studies, which limits the ability of external reviewers to verify claims. Most importantly, the focus on matrix porosity ignores the role of fractures and secondary porosity, which are often the primary pathways for radionuclide transport. These issues matter to the community because they directly impact the long-term safety of our regional water systems and the integrity of the repository environment.
Path Forward
We recommend that the proponent complete and publish all kinetic geochemical testing results before finalizing the impact assessment. A detailed sensitivity analysis of the 5 percent subordinate rock types, such as amphibolite and dykes, is necessary to ensure localized sulfur or metal concentrations are not overlooked. Additionally, the geochemical baseline must be expanded to include a broader spatial distribution of boreholes to confirm the claimed lithological homogeneity. Transparency must be improved by making internal Confidence in Safety reports easily accessible to the public and independent reviewers. Future submissions must also clarify how measured connected porosity relates to macro-scale fracture networks, as these features are critical for understanding potential radionuclide transport.
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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