Water is a critical component of our mining and processing activities, and we actively manage its use, storage, and treatment to protect the environment and maintain regulatory compliance as water is a shared resource that supports local communities, Indigenous Peoples, and surrounding ecosystems.
Across our operations, water is used for mineral processing (including grinding and ore recovery), dust suppression on roads and active work areas, underground drilling and blasting activities, and as part of our tailings transport and deposition systems. We also use freshwater in paste backfill systems at Kiena, reducing the volume of tailings stored on the surface and supporting more efficient resource use.
We use water management standards, operational procedures, monitoring programs, and treatment technologies to manage water use, maintain water quality, support regulatory compliance, and reduce potential impacts on surrounding ecosystems and communities. At both Eagle River and Kiena, water balances are important for us to be able to understand, predict, and manage water inputs, outputs, and storage. This enables informed operational planning, targeted infrastructure investment, and continuous improvement in water efficiencies. Wesdome’s operations are not located in areas or regions of high or extremely high baseline water stress.1
Water management is governed by our Tailings Management and Water Stewardship Policy, as well as our Environmental and Sustainability policies. We are aiming to align with Level A requirements under the Mining Association of Canada’s Towards Sustainable Mining (TSM) Water Stewardship Protocol.
Water risks are managed through site-specific controls focused on water availability, water quality, and regulatory compliance. These controls are supported by monitoring systems, water treatment infrastructure, and operational planning processes designed to maintain performance, support compliance, and mitigate potential environmental impacts. More detailed information on how we manage water across our operations is provided on our website.
In 2025, we updated our water management processes at Kiena to align with MAC TSM Level A requirements, which included developing and implementing a water management manual focused on optimizing water use.
Eagle River experienced three effluent exceedances at a discharge location related to total suspended solids and un-ionized ammonia. Investigations identified contributing factors including extreme runoff during a rain-on-snow event, elevated solids from underground sump cleaning activities, and a localized ammonia exceedance. In response, the operation strengthened monitoring and operational controls, reviewed blasting and water management practices, improved coordination between Environment and Operations teams, implemented sediment control measures, and advanced plans for settling pond dredging in 2026 to improve long-term treatment performance and reduce recurrence risk.
Kiena did not experience any incidents of non-compliance associated with water quantity or quality permits, standards, or regulations in 2025. Neither site experienced any significant spill events. Further details on how we manage spills are available under Waste and Hazardous Materials.
1 Both Eagle River and Kiena are located in regions of ‘low’ baseline water stress, as classified by the World Resources Institute’s (WRI) Water Risk Atlas tool, Aqueduct.
Over 1.9M cubic metres of water under management across our operations in 2025.
Annual Performance Summary
Eagle River and Kiena experienced different trends in total freshwater withdrawn in 2025 compared to 2024, primarily influenced by changes in precipitation and site water management strategies. At Eagle River, total freshwater withdrawal increased from 929.0 thousand m3 in 2024 to 1,053.0 thousand m3 in 2025, largely driven by higher volumes of rainwater captured, stored and managed on site. In contrast, Kiena recorded a decrease in total freshwater withdrawn from 1,012.3 thousand m3 in 2024 to 925.9 thousand m3 in 2025, reflecting lower precipitation inputs. However, Kiena experienced an increase in the use of surface water to support operations in 2025. Further details on our water usage during the year are available in our ESG Data Book.
Water consumption at both sites was higher in 2025 than in 2024. At Eagle River, consumption increased from 77.7 thousand m3 in 2024 to 96.4 thousand m3 in 2025. Water consumption refers to water used or lost through operational activities that is not returned to the same watershed. The recorded increase was primarily associated with higher mining and processing activity during the year, which increased overall operational water demand. At Kiena, water consumption increased from 265.7 thousand m3 to 348.4 thousand m3.2 The increase in water consumption reflects higher operational water demand associated with increased mining and processing activity, combined with a lower proportion of water being recycled.
We registered higher levels of cyanide in water discharged off-site on several occasions at Eagle River in 2025. Following investigation, these higher readings were found to be a result of laboratory testing issues, and did not lead to any official non-compliances.
During the reporting period, we focused on pursuing efficiencies in how we manage water at both sites. At Eagle River, our efforts centred on further optimizing operations at the reverse osmosis plant, enabling us to discharge 862.6 thousand cubic metres of treated water. At Kiena, we began installing flow meters at major intake valves to improve data collection and monitoring of our water use, with this work set to continue in 2026. We additionally improved our control of effluents by putting in a new decant tower, to be completed in early 2026, and a new sewage treatment system at the site.
We updated our operational water balances at both Eagle River and Kiena in 2025. At Kiena, the update enabled us to better predict water levels in the tailings management areas and to improve our management of snowmelt. Eagle River is in the process of incorporating the mine water balance into GoldSimTM to allow for better accessibility to data as well as scenario-building.
Kiena continued to participate in the Abitibi-Témiscamingue watershed management committee (Organisme de bassins versants de l’Abitibi-Témiscamingue) and to implement its residential and well monitoring program, with final results of the 2025 program expected in 2026.
In 2026, we will continue to strengthen water management practices across our operations. At Eagle River, this includes the development of an integrated site-wide Water Management Plan as well as updates to spill prevention and contingency planning. At Kiena, efforts will focus on advancing monitoring systems and improving data collection and reporting efficiency.
2 Starting in 2025, we changed how we calculate water consumption at Kiena in order to improve alignment with SASB requirements. The new calculation now includes water evaporation, contributing to an increase in water consumed. As a result, the total water consumption for Wesdome was recalculated for the years 2022 to 2024. Previously reported values were revised as follows: for 2022, from 83.9 to 313.4 thousand cubic metres (+274%); for 2023, from 111.5 to 249.1 thousand cubic metres (+123%); and for 2024, from 183.9 to 343.3 thousand cubic metres (+87%). The figure for 2021 was not included in the recalculation.
Performance
Indicators:
SASB: EM-MM-140a.1, EM-MM-140a.2
GRI: 2-4, 2-27, 3-3, 303-1 (partial), 303-3 (parital), 303-4 (partial), 303-5 (partial)
