Tailings Areas Added for Marathon Palladium

Summary#

These final regulations amend the Metal and Diamond Mining Effluent Regulations to list 10 water bodies near Marathon, Ontario as areas where mine waste can be deposited for the Marathon Palladium Project. The change took effect on July 19, 2024 and will permit the destruction of 3.66 hectares of fish habitat, subject to an approved compensation plan.

What it does#

• Adds two individual water bodies and two geographic areas (together covering 10 water bodies) to Schedule 2 of the Metal and Diamond Mining Effluent Regulations (MDMER), designating them as tailings impoundment areas where mine waste may be placed.
• Allows Generation PGM Inc. to use those listed waters for tailings and some mine rock storage for its open‑pit platinum group metal and copper mine about 10 km from Marathon, Ontario.
• Estimates the direct loss of fish habitat at 3.66 hectares.
• Requires the company to have an approved fish habitat compensation plan (FHCP) before any mine waste is deposited. The FHCP aims to create 11.74 hectares of new or improved fish habitat (a net increase of 8.08 hectares).
• Requires the company to put up an irrevocable financial guarantee to cover FHCP implementation costs estimated at $1.9 million over 10 years.
• Ongoing monitoring, government inspections, and Fisheries Act authorizations remain required before and during project activities.

Who's affected#

• Generation PGM Inc., the mine proponent, which needs the regulatory listing and must fund and deliver the FHCP.
• Local fishers and recreation users who use the small streams and ponds near the mine site.
• Nearby Indigenous communities consulted about the project and compensation measures, including Biigtigong Nishnaabeg, Ginoogaming First Nation, Métis Nation of Ontario, Long Lake #58 First Nation, Jackfish Metis Association, and Pays Plat First Nation. Some raised concerns about how and where habitat compensation will be done.
• Federal agencies involved in approval and enforcement, including Environment and Climate Change Canada and Fisheries and Oceans Canada.
• People living in and around Marathon, Ontario who may be affected by mine construction, operations, and any related water‑management activities.

Why it matters#

• The regulation permits the direct loss of fish‑frequented waters to make room for mine waste rather than requiring only land‑based storage. That is significant because the Fisheries Act generally protects fish habitat.
• The government requires offsetting habitat so the project claims a net gain in habitat (11.74 ha created vs 3.66 ha lost). How well the compensation works will determine real effects on local fish populations and on fishing and traditional use.
• Some Indigenous groups raised concerns about distance and type of compensation (for example, the main compensation site, Ramsay Lake, is about 83 km from the mine). Those concerns are being addressed through further consultation and conditions in Fisheries Act authorizations.
• The company must post a financial guarantee ($1.9 million) and get FHCP approval before putting waste in the listed waters, and regulators will inspect and monitor compliance.