Mining environmental compliance in Ontario requires proponents to identify the approvals, operating conditions, monitoring duties, and closure obligations that apply at each project stage.
This page covers the principal provincial and federal requirements for mining companies, investors, and project developers, including environmental assessments, water and air approvals, tailings management, remediation, and current permitting reforms.
Ontario Environmental Compliance Framework For Mining
Environmental protection is shared between the federal and provincial governments.
In Ontario, the Ministry of Energy and Mines oversees the mineral sector and administers the Mining Act, while the Ministry of the Environment, Conservation and Parks administers legislation governing pollution, waste, water, and environmental assessments.
Federal environmental compliance is administered by several agencies, depending on the nature of the project:
Depending on the project, proponents may also need approvals or authorizations from additional federal authorities.
Ontario’s One Project, One Process framework coordinates provincial permitting for designated advanced exploration and mine development projects. An accepted proponent is assigned a government team to coordinate applications and reduce duplication, but the underlying technical and environmental requirements still apply.
Environmental Assessment Requirements
Ontario has moved toward a project-list approach under the Environmental Assessment Act.
A mining project is not automatically subject to the same environmental assessment process as every other mine. A comprehensive assessment may be required when a project or class of projects is designated, while other government decisions may involve streamlined or ministry-specific review processes.
Where a comprehensive assessment is required, the proponent may need approved terms of reference establishing how the assessment will be prepared.
Provincial Environmental Assessments
Provincial environmental assessments may consider effects on land, water, wildlife, communities, and other environmental interests. The assessment process does not replace separate permits.
Federal Impact Assessment Act
A federal impact assessment may apply to a designated project under the Impact Assessment Act or where federal jurisdiction is otherwise engaged. Federal review can address environmental effects, Indigenous rights, federal lands, fisheries, navigation, and other matters within federal authority.
Key Permits & Approvals
The approval plan should be developed around the proposed work rather than a standard checklist. Common requirements may include:
- Exploration plans or permits under the Mining Act
- Environmental Compliance Approvals
- Permits to take water
- Authorizations for sewage or effluent systems
- Land-use and access approvals
- Closure plans and financial assurance
- Federal approvals where applicable
Water Discharge Permits
A permit to take water is generally required when more than 50,000 litres of water will be taken in one day, subject to exemptions and activities that may instead require Environmental Activity and Sector Registry registration. The permit application should reflect the water source, volume, duration, effects on other users, and proposed monitoring.
Discharges may require separate approvals. The project may also be subject to conditions governing treatment, sampling, reporting, and the quality of water released into the environment.
Air Emissions Approvals
An Environmental Compliance Approval may be required before constructing, operating, or modifying a facility that could affect the public or the natural environment.
For mining projects, this may include activities or equipment such as crushing, blasting, mineral processing, generators, dust emissions, and noise.
Mine Closure Plans & Financial Assurance
Before advanced exploration or mine production begins, the applicable closure-planning requirements should be addressed.
A closure plan describes how the site will be rehabilitated and ordinarily includes financial assurance intended to cover the required rehabilitation work. Ontario also requires closure plans to address progressive rehabilitation during the project lifecycle.
Tailings Management And Storage
Tailings and waste-rock facilities can create long-term water, stability, dust, and remediation obligations. Project planning should address facility design, seepage and runoff, monitoring, emergency procedures, progressive rehabilitation, and post-closure care.
Approvals and commercial agreements should also allocate responsibility for construction, operation, reporting, maintenance, and remediation. These obligations can affect project financing and transaction due diligence.
Environmental Liability And Remediation
Environmental liability may arise from spills, unauthorized discharges, non-compliant waste handling, historic contamination, or failure to satisfy approval conditions. In an acquisition, the parties should review:
Legal due diligence should be coordinated with technical environmental review. The appropriate allocation of liability may depend on whether the transaction involves project assets, corporate shares, or a joint venture interest.
Ongoing Monitoring And Reporting
Environmental compliance continues after permits are issued. Changes to production, equipment, discharge points, or facility design should be reviewed before implementation because they may require an amended approval.
Book A Consultation
Licata Law provides legal support involving mining projects, regulatory matters, and commercial agreements.
A mining agreements lawyer from Licata Law can help assess approval conditions, contractual risk allocation, and environmental issues identified during a transaction or project-development process.
Learn more about working with a mining lawyer in Toronto and our firm’s corporate commercial law services, and schedule a consultation with us.