Mining involves several stages which occur in a sequence known as the mining sequence which is divided into 5 stages:

  1. Early exploration
  2. Advanced exploration
  3. Mine development
  4. Mine production
  5. Closure

The mining sequence covers all aspects of mining, including:

  • prospecting for mineral deposits
  • analysing the profit potential of a proposed mine
  • extracting desired materials
  • rehabilitating all lands used for mining to their original state, or alternate use or condition
This is a flow chart that illustrates five stages of the mining sequence beginning with early exploration, moving to advanced exploration, development, production and finishing with closure. Arrows depict the timing of various activities during the mining sequence:  - consultation and progressive rehabilitation happen throughout the mining sequence. - Prospecting and claim registration are early exploration activities.  - Permitting is required at the early exploration stage, as well as throughout the advanced exploration stage and at the beginning of the development stage.  - Environmental and feasibility studies are conducted during the advanced exploration stage.  - Construction of a mine is during the development stage.  - Mining is during the production stage. - Rehabilitation happens during the closure stage.  This flow chart also illustrates how the Early exploration , advanced exploration, development and closure stages of the mining sequence require a mining company to spend money while only the production phase allows it to make money.- consultation and progressive rehabilitation happen throughout the mining sequence. - Prospecting and claim registration are early exploration activities.  - permitting is required at the early exploration stage, as well as throughout the advanced exploration stage and at the beginning of the Development stage.  - Environmental and feasibility studies are conducted during the advanced exploration stage.  - Construction of a mine is during the development stage.  - Mining is during the production stage. - Rehabilitation is during the closure stage.  This flow chart also illustrates how the Early exploration , advanced exploration, development and closure stages of the mining sequence require a mining company to spend money while only the production phase allows it to make money.


Consultation happens throughout the mining sequence with:

  • Aboriginal communities
  • the public
  • surface rights owners and holders

Aboriginal communities

Contact with Aboriginal (First Nation and Métis) communities is made and maintained throughout the mining sequence.

Regulations under the Mining Act provide a framework for authorizing mineral exploration and development activities. The Consultation framework:

  • outlines steps to meaningfully consult with Aboriginal communities whose Aboriginal or treaty rights may potentially be adversely affected by proposed mineral exploration or mine production activities
  • provides information and direction to proponents (the person, company or agency proposing a project) and communities about how we will implement the consultation framework


Contact with the public (people living in Ontario) is made and maintained throughout the mining sequence. Changes to the land may:

  • influence recreational activities
  • raise environmental concerns
  • raise health or safety concerns

We notify the public for:

  • early exploration permitting
  • environmental assessment processes
  • advanced exploration projects
  • the development of a new mine
  • the significant amendment of an existing mine’s closure plan
  • the rehabilitation of an abandoned mine site

Public consultation can include:

Surface rights owners and holders

Surface rights are all the rights to the land above and below the surface, other than the mining rights.

A surface rights owner is an owner of the land who does not own the mining rights for the land.

A surface rights holder is a person to whom the surface rights of land have been granted, sold, leased or located.

In some cases, contacting surface rights owners and holders is a requirement under the Mining Act, such as when:

  • registering a mining claim
  • transferring a mining claim
  • submitting an exploration plan
  • applying for an exploration permit
  • applying to voluntarily rehabilitate a mine hazard

We also highly recommend contacting surface rights owners and holders before:

  • accessing the project area for initial prospecting or sampling
  • beginning new exploration activities
  • making changes to existing exploration activities
  • creating a closure plan
  • beginning construction of a mine
  • beginning mine production
  • beginning progressive rehabilitation during operations and for rehabilitation work at closure

You can identify the surface rights owner of a piece of land by performing a title search through ONLand.

For more information on contacting surface rights holders, contact the Data Management Unit.

Progressive rehabilitation

Progressive rehabilitation is:

  • rehabilitation done continually and sequentially throughout the life span of a project or mine hazard
  • a legal obligation under the Mining Act

Proponents must take all reasonable steps to progressively rehabilitate a site, whether or not:

  • closure has commenced
  • a closure plan has been filed

If a project is not subject to a closure plan, progressive rehabilitation still applies. In this case, the proponent must:

  • complete the progressive rehabilitation work to the appropriate prescribed standard
  • submit a detailed report to the minister within 60 days of completing the progressive rehabilitation work

Once lands are not actively being disrupted by a mining project, you may commence progressive rehabilitation of those lands, rather than wait until closure. Many new mining projects in development reflect this design-for-closure approach. All Ontario closure plans must describe their anticipated progressive rehabilitation schedule.

For prescribed early exploration activities, proponents must follow the:

For advanced exploration or mine production sites subject to a closure plan, proponents are required to describe the progressive rehabilitation measures they anticipate will be undertaken as part of the closure plan.

Early exploration

Early mineral exploration covers objectives and activities that begin with:

The type of work carried out depends on the minerals being sought. If early exploration leads to a mineral discovery, advancing it to development typically requires a large investment and years of work.

Ontario Geological Survey data

The Ontario Geological Survey collects data about Ontario's geology. They provide access to published reports, maps and digital data, through:

Visit the Ontario Geological Survey for more information about:

  • our geoscience library
  • Geoscience Laboratories (GeoLabs)
  • the Resident Geologist Program

Early exploration on registered mining lands

Registering a mining claim grants the claim holder the exclusive right to:

  • explore for minerals
  • obtain a lease of the mining claim if they have satisfied the requirements of the Mining Act

Early exploration activities can also be performed on:

A wider range of early exploration activities can be performed on mining lands to:

  • confirm the presence of a mineral deposit
  • investigate its delimitation (boundaries)

Early exploration activities

The following are examples of early exploration activities that can be carried out after registering a mining claim, or on other mining lands (lease, licence of occupation and patent):

  • prospecting
  • geological mapping
  • sampling
  • airborne and ground survey work
  • bedrock trenching
  • pitting
  • overburden stripping and related manual work
  • exploratory drilling

Early exploration activities can have potential adverse effects to Aboriginal and treaty rights. Proponents may have to get an exploration plan or permit, under Ontario Regulation 308/12.

Proponents can submit an exploration plan or apply for an exploration permit through MLAS.

Assessment work

Certain types of early exploration activities constitute assessment work. The costs related to assessment work activities are eligible for credits. These assessment work credits:

  • are attached to the mining lands where the exploration activities were performed
  • can be assigned to a mining claim or distributed to other mining claims to satisfy their assessment work requirements

To keep a mining claim in good standing, proponents must:

  • complete and report assessment work to the ministry
  • assign or distribute their assessment work credits

You can register a mining claim and report assessment work online in MLAS.

For help with assessment work, read the:

Payment in place of assessment work

Claim holders can make a monetary payment to fulfill the current year’s assessment work requirement.

There are restrictions to payments in place of assessment work. Read Section 5 of the Assessment Work regulation for more information.

Advanced exploration

If the results of early exploration activities are successful, a project could move towards advanced exploration.

Large-scale field exploration which meets a certain list of criteria is considered advanced exploration. Advanced exploration is subject to additional requirements and regulations.


Mineral exploration activities are classified as advanced exploration if they involve one or more of the following:

  • excavation of an exploratory shaft, adit or decline
  • extraction of material in excess of the prescribed quantity, whether the extraction involves the disturbance or movement of prescribed material located above or below the surface of the ground
  • installation of a mill for test purposes
  • any other prescribed work


Before beginning advanced exploration, a proponent must meet certain requirements.

These requirements include:

  • obtaining a lease of a mining claim to gain the right to extract minerals
  • submitting a Notice of Project Status form to the ministry
  • consulting with all required parties
  • submitting a closure plan with accompanying financial assurance and having it filed by the ministry
  • getting permission to test bulk samples for mineral content and to dispose of material if the advanced exploration is carried out on a mining claim
  • acquiring all required permits and approvals from ministries, agencies and government organizations

Contact a local office of the Mineral Exploration and Development Section for more information on:

  • determining if proposed activities would be classified as advanced exploration
  • complying with advanced exploration requirements


Evaluation is the process of determining if a mineral deposit is economically viable to extract.

The evaluation of a project or mineral deposit will progress through a number of studies if it shows promise, including:

  • mineral resource estimate or national instrument 43-101 report (generally done by third party contract engineering firms)
  • preliminary economic assessment
  • pre-feasibility study
  • a final, or bankable feasibility study (a final decision on whether to develop a mine is generally made at this point)

Evaluation studies generally involve a detailed analysis of:

  • geology
  • mining methods
  • mineral processing
  • human resource requirements
  • infrastructure needs
  • economics, including price forecasting, wages and financing
  • expenditures for the predicted life of the mine

Only a small number of early exploration programs turn into discoveries. A decision to proceed to mine development can only be made after:

  • sampling, drilling and engineering studies have more clearly defined the extent of the deposit
  • economic studies have concluded

Mine development

Development is the process of constructing a mine and the infrastructure to support it.

This phase of the mining sequence cannot be done on unpatented mining claims. You must first obtain a lease of the mining claim(s).

Learn more about mining leases.

Mine construction

Mine development may involve many activities such as:

  • preparing the mine site by clearing trees and blasting rock
  • constructing mining facilities such as head frames, administration buildings or mechanical shops
  • installing infrastructure such as power lines and substations, roads or water lines


Before beginning development, a proponent must meet certain requirements, including:

  • securing the appropriate mining land tenure for the project
  • submitting a Notice of Project Status form to the ministry
  • consulting with all required stakeholders
  • filing a closure plan with accompanying financial assurance and certifications
  • acquiring all required permits and approvals from ministries, agencies and government organizations

Closure plan

A closure plan is a plan for rehabilitating the affected site:

  • throughout advanced exploration or mine production activities
  • once the site is closing

A closure plan includes financial assurance. Financial assurance allows the ministry to implement the identified rehabilitation measures for each mine feature that is created or disturbed through advanced exploration or mining activities if the proponent fails or refuses to do so.

Before mine development can begin, you must submit a closure plan and have it filed by the ministry.

Closure plan process

Step 1: Proponent submits a Notice of Project Status form (or Notice of Material Change form) to the ministry

Step 2: Ministry provides written direction on delegation of procedural elements of consultation to proponent within 45 days

Step 3. Proponent prepares a plan for consultation for ministry review and direction

  • ministry provides ongoing oversight and direction
  • proponent carries out delegated aspects of consultation
  • proponent reports to ministry until the minister is satisfied that appropriate consultation with Aboriginal communities has been carried out

Step 4: Proponent submits Closure Plan (or Closure Plan Amendment)

Step 5: Ministry acknowledges the filing or return of the Closure Plan (or Closure Plan Amendment) within 45 days

Content and format

Find the required format and content of a closure plan in Schedule 2 of Ontario Regulation 35/24.

The Closure plan boundary and land tenure guideline (PDF) provides additional details on the scope and geographical boundaries of closure plans.


Closure plans and closure plan amendments must be certified by either:

  • the proponent
  • where the proponent is a corporation, 2 of the proponent’s senior officers, including the most senior financial officer

Many technical aspects in closure plans must be certified by qualified persons. The form and content of these certifications is set out in Ontario Regulation 35/24.

Download the certification forms for proponents and qualified persons.

Conditional filing orders

Closure plans and amendments must meet all legal requirements at the time of submission. Otherwise, they cannot be filed by the ministry.

If you do not meet a legal requirement at the time of submission, you may request a conditional filing order. Orders are:

  • granted by the minister
  • allow for the submission to be filed subject to terms and conditions imposed by the minister


Once you have a filed closure plan, you can only undertake activities that are included in and consistent with that closure plan, unless:

  • you submit a closure plan amendment
  • the amendment is filed by the ministry

To request an amendment, submit a Notice of Material Change form. Describe the proposed changes that will materially affect your filed closure plan.

Rehabilitation standards

In Ontario, proponents undertaking mine development are required to rehabilitate the mine hazards created by their activities.

A mine hazard is any feature of a mine, or any disturbance of the ground, that has not been rehabilitated to the prescribed standard. Mine hazards may include:

  • mine openings to the surface
  • open pits
  • waste rock piles
  • tailings dams and other containment structures
  • surface infrastructure

Most types of mine hazards have minimum prescribed standards for rehabilitation. These standards define requirements, including:

  • acceptable material for capping openings
  • minimum load specifications
  • engineering inspections
  • necessary signage

Rehabilitation tasks and standards, broken down by type of hazard, are outlined in the Mine Rehabilitation Code (PDF).

The Mine Rehabilitation Code (PDF) incorporates other standards and documents by reference, including:

  • Drawing No. 94103-M1 (PDF): "Monolithic concrete cap typical plan and section" that is referenced in the Mine Rehabilitation Code of Ontario (Schedule 1, Part 1, section 4 i).
  • Drawing No. 94103-M2 (PDF): "Typical monolithic concrete cap reinforcement schedule" that is referenced in the Mine Rehabilitation Code of Ontario (Schedule 1, Part 1, section 4 i).
Rehabilitation exemptions

In limited circumstances, the minister may grant exemptions from requirements to complete a rehabilitation measure.

Send your written request for an exemption by email to PartVIIsubmissions@ontario.ca.

Post-closure state determination

Most closure plans reflect the rehabilitation measures necessary to return a site to its prior use or condition.

In some circumstances, closure plans can return the lands to another post-closure state, as long as the minister approves. This allows for the adaptive reuse of mine sites for other purposes, such as:

  • tourism
  • recreation
  • wildlife habitat
  • alternate industry

Financial assurance

Financial assurance must be submitted with the closure plan and be held by the ministry.

Financial assurance ensures that the rehabilitation work outlined in a closure plan is successfully performed, even if the proponent is unwilling or financially unable to undertake the work.

Financial assurance must be certified to be adequate and sufficient to cover the cost of the rehabilitation work required to comply with:

Forms of financial assurance

You can provide financial assurance in one of the following forms:

  • Cash.
  • A letter of credit from a bank named in Schedule I or II of the Bank Act. A letter of credit is a document issued by a bank agreeing that it will pay money to a beneficiary, on behalf of the bank's customer, if certain events take place.
  • A bond of a guarantee company approved under the Insurance Act. A bond (surety bond) is a document issued by a guarantee (insurance) company agreeing to pay money to an obligee if certain events take place.
  • A mining reclamation trust as defined in the Income Tax Act.
  • Compliance with a corporate financial test in the prescribed manner.
  • Any other form of security or any other guarantee or protection, including:
    • a pledge of assets
    • a sinking fund
    • royalties per tonne
    • any type of phased financial assurance that meets any prescribed requirements and that is acceptable to the minister

Phased financial assurance

Phased financial assurance means proponents can submit financial assurance in installments that are scalable to development of the site, rather than submitting the entire amount of financial assurance for all development activities up-front before the preliminary work begins.

You may submit financial assurance in phases if the phased approach:

  • complies with prescribed requirements
  • is accepted by the minister

The requirements for phased financial assurance are set out in section 21 of Ontario Regulation 35/24.

At any time during a project, the minister must hold adequate and sufficient financial assurance to cover the costs of the rehabilitation work required under the closure plan for each mine hazard located on the site at that time.

Phased financial assurance must correspond with the mine’s development schedule. You cannot develop a mine feature until the minister has received financial assurance for its rehabilitation.

Submission schedule

You must submit your financial assurance for the first phase in a phasing schedule together with the initial submission of the closure plan.

You must submit your financial assurance for subsequent phases to the minister at least 45 days before the planned start of any activity in the phase. Activities in the phase may begin only once the ministry holds sufficient financial assurance for the rehabilitation of mine features or hazards to be created in that phase.

To avoid project delays, you should consider submitting amendments to your closure plans before this 45-day deadline. This will ensure you have enough time to get a revised financial assurance instrument (such as an amended letter of credit) from your financial institution.

If you do not comply with a phasing schedule, the minister can require some or all of the outstanding amount of financial assurance on an accelerated basis.

Failure to comply with a phasing schedule is also an offence under the Mining Act.

Financial assurance held by the ministry

You can find information about amounts of financial assurance held by the ministry in the Financial Assurance Table (XSLX). We update this table regularly.

Financial assurance resources

Mine production

Production is the process of extracting any mineral or mineral-bearing substance for:

  • immediate sale
  • stockpiling for future sale


Mine operations include the following activities:

  • excavating earth and rock
  • processing the excavated material to separate the ore from the waste rock
  • storing and maintaining waste material
  • monitoring environmental conditions such as air quality, water quality and noise levels
  • operation supporting services such as:
    • repair shops
    • labs
    • living quarters
    • warehouses
    • offices
  • exploration to expand known deposits and find new ones to increase the mine life
  • progressive rehabilitation

For more information about immediate and long-term mine operation activities, contact the Mineral Exploration and Development Section or one of our local offices.


Closure is the process of finishing the rehabilitation of a mine site after mining activities have ceased.

Mine closure

Mine closure follows the completion of mineral extraction, processing and transportation activities of the mined materials.

Mine closure is a formal process of planning, managing and implementing the closing out of a mine site. You must:

  • undertake rehabilitation activities to help avoid issues that would impact the environment, public health and safety
  • carry out monitoring programs to ensure that rehabilitation has been successfully completed

Rehabilitation often starts with:

  • stabilizing underground mine features and openings to surface
  • treating open pits
  • removing or treating features to prevent environmental contamination
  • removing site facilities and infrastructure that supported the mining project

Once a mine is fully rehabilitated and closed out, the land tenure can be surrendered, where appropriate.

Land restoration

The standards for mine rehabilitation and closure planning include requirements to restore lands to an appropriate condition after you close out a mining project.

Increasingly, proponents are developing methods of mine closure where mine sites are adapted or reused for other beneficial land uses. This may also involve repurposing infrastructure.

These post-closure land uses are allowed if approved by the minister.

You can find Ontario’s rehabilitation standards in:

Return of financial assurance

Financial assurance must be provided with a closure plan. This allows the ministry to implement the identified rehabilitation measures if the proponent fails or refuses to do so.

The ministry retains all financial assurance provided with a closure plan until we accept an application to reduce financial assurance. There are two grounds for an application for a reduction in financial assurance:

  • rehabilitation work has been performed in accordance with a filed closure plan
  • a reduction in financial assurance is justified in a Notice of Material Change form as a result of a documented change in the scope of a project

Before we accept an application for a reduction in financial assurance, we may inspect the mine site to determine whether the grounds have been met.

Surrendering land tenure

Many mine projects operate from lands that are leased or licensed from the province.

You must return these lands to the province when the lease or license is no longer necessary.

Our closure planning requirements ensure that when land tenure returns to the Crown, there are no inherited liabilities created for the province.

Lands that are owned in fee simple, rather than leased, are typically transferred to third parties before the corporation dissolves. However, these lands can be returned to the province if the corporation dissolves without first divesting (selling) the lands.

Surrendering a lease or license

When you close out a mine project that operates on mining leases or licenses of occupation, you may need to surrender the lease or license.

Submit an Application to Voluntarily Surrender Mining Lands/Mining Rights form.

Mineral development project resources

Our Mines and Minerals Division has Mineral Exploration and Development Consultants (MEDCs) who are available to:

  • discuss the details of your mineral development project
  • provide guidance, consultation and oversight

To get in touch with a MEDC, contact the Mineral Exploration and Development Section or one of our local offices.

The following resources can also help you properly plan and implement a mineral development project through all stages of the mining sequence:

  • Regulatory requirements outside of the ministry (PDF) provides a listing and descriptions of some of the regulatory permits and other requirements for common activities related to mineral exploration and development. The document contains a left navigation pane. If your browser does not show this pane, save the PDF file to your computer and view it with Adobe Acrobat Reader.
  • One window coordination process (PDF) provides an overview of legislation and regulations, including environmental assessments and details on how to work with the ministry to coordinate with other regulators.
  • The Project definition template (DOC) outlines the information proponents should collect at the early stage of advanced exploration, mine production or development project planning to maximize the amount of advice that regulators can provide them. This will result in efficient delivery of regulatory advice, permits and approvals.