Guide to the regulatory process for listing water bodies frequented by fish in Schedule 2 of the Metal and Diamond Mining Effluent Regulations
1.0 Acronyms
AA
Assessment of alternatives report
CNWA
Canadian Navigable Waters Act
DFO
Fisheries and Oceans Canada
ECCC
Environment and Climate Change Canada
FA
Fisheries Act
FHCP
Fish habitat compensation plan
MDMER
Metal and Diamond Mining Effluent Regulations
CNWA
Canadian Navigable Waters Act
1.1 Disclaimer
This document outlines the process and conditions for listing water bodies frequented by fish to Schedule 2 of the Metal and Diamond Mining Effluent Regulations (MDMER) to designate them as tailings impoundment areas (TIAs).
This document is not a legal document. It is meant to guide owners and operators of a mine through the process of listing waters frequented by fish to Schedule 2 of the MDMER.
For the purpose of interpreting and applying the law, readers should consult:
- the Acts as passed by Parliament, which are published in the "Assented to" Acts service, Part III of the Canada Gazette, and the annual Statutes of Canada
- the Regulations, as registered by the Clerk of the Privy Council and published in Part II of the Canada Gazette
These publications are available in most public libraries and online. Official versions of the Statutes and Regulations can also be found at the Department of Justice website. The law as stated in these publications will prevail should any inconsistencies be found in this document. Laws, Regulations and guidelines are subject to amendments from time to time. Each version is dated, so readers should always ensure to consult the most recent version. Readers can contact ECCC for more information.
1.2 Purpose of the guide
The purpose of this document is to outline the process for listing water bodies frequented by fish to Schedule 2 of the MDMER to designate them as tailings impoundment areas (TIAs) and the conditions required for Governor in Council (GIC) approval.
1.3 Context
The Fisheries Act prohibits the deposit of deleterious substances into waters frequented by fish, unless the deposit is authorized by regulations. The MDMER are regulations made pursuant to subsections 34(2), 36(5) and 38(9) of the Fisheries Act. These regulations apply to metal and diamond mines, milling facilities and to hydrometallurgical facilities that have an effluent flow rate of at least 50 m3/day from all mine effluent discharge points and deposit deleterious substances into waters frequented by fish. ECCC is responsible for the implementation and enforcement of section 36(3) of the Fisheries Act and the MDMER.
The MDMER contain provisions to allow for the disposal of mine wasteFootnote 1 in waters frequented by fish under certain conditions. The use of waters frequented by fish for mine waste disposal can only be authorized through a regulatory amendment to list a water body in Schedule 2 of the MDMER to designate it as a tailings impoundment area. Any proposed amendment must meet specific conditions for regulatory approval before the Minister of the Environment can recommend it to the GIC.
2.0 Overview of the regulatory amendment process
For any project where the proposed deposit of mine waste into water frequented by fish or any place where deleterious substances from the deposit of mine waste may enter such water, will require an amendment to Schedule 2 of the MDMER and approval of a fish habitat compensation plan (FHCP).
The MDMER may authorize the use of fish-frequented water bodies for the disposal of mine waste where the proponent has demonstrated through an assessment of alternatives report that these locations represent the best options from an environmental, technical, economic, and socio-economic perspective.
The MDMER requires the development and implementation of a FHCP that meets all the requirements under section 27.1 of the Regulations to offset the loss of fish habitat that would occur as a result of the use of a water body for mine waste disposal. The Minister of the Environment must approve the FHCP before any mine waste may be deposited in water bodies listed in Schedule 2 of the MDMER. This approval is based on advice from Fisheries and Oceans Canada (DFO). The owner or operator of a mine is also required to submit an irrevocable letter of credit or an equivalent financial guarantee to ensure that funds are in place should the owner or operator fail to address all the elements of the FHCP.
The regulatory process includes consultations on proposed amendments to seek feedback and address concerns on the assessment of alternatives report and the FHCP.
Before the Minister of the Environment can recommend a regulatory amendment for consideration by the GIC, certain requirements must be met. These requirements are detailed in the sections below.
An overview of the regulatory process for amendments to Schedule 2 of the MDMER and the responsibilities of ECCC and the proponent is provided in Figure 1.
2.1 Assessment of alternatives
The proponent is responsible for preparing the assessment of alternatives report (AA) on mine waste disposal. They must demonstrate that the preferred option is the best one based on the environmental, technical, economic, and socio-economic criteria set out in ECCC’s Guidelines for the assessment of alternatives for mine waste disposal (the Guidelines).
The AA is reviewed by ECCC to ensure that the report is developed in accordance with the Guidelines. Once this has been determined, the report will be ready for public and Indigenous consultationsFootnote 2 . The project proponent participates in the consultations to directly communicate the results of their alternatives assessment and its conclusions to all engaged parties. Note that during consultation, modifications to the AA report may be required in response to comments from Indigenous communities and the public.
2.2 Fish habitat compensation plan
The MDMER requires the project proponent to develop and implement a FHCP that meets all requirements under section 27.1(2) of the Regulations to offset the loss of fish habitat resulting from the deposit of mine waste into a water body frequented by fish.
The FHCP will be reviewed by DFO in accordance with its policies. If the FHCP is deemed adequate, DFO will recommend it to ECCC prior to ECCC proceeding with consultations. Note that during consultation, modifications to the FHCP may be required in response to comments from Indigenous communities and the public.
2.3 Consultation
Throughout the regulatory amendment process, ECCC works with mine proponents and DFO to ensure that Indigenous communitiesFootnote 3 and all interested parties are consulted and involved in the development of the assessment of alternatives report and the fish habitat compensation plan. ECCC recommends that consultation on the AA and FHCP be included during the federal, provincial, or territorial environmental assessments or throughout mining planning activities. Providing this information early and frequently for the purpose of consultation can reduce the time required for the regulatory amendment process.
DFO must deem the proposed FHCP as adequate per DFO’s Policy (for applying measures to offset adverse effects on fish and fish habitat under the Fisheries Act) and ECCC must determine that the AA report was developed in accordance with the Guidelines on the assessment of alternatives. After this has been confirmed, ECCC will organize consultations with impacted Indigenous communities and with the public.
To undertake consultations with Indigenous communities and the public, proponents will be required to provide the following to ECCC:
- a general overview of the project in English and French
- a plain language summary of the assessment of alternatives report in English and French
- a plain language summary of the compensation plan that includes the information required under section 27.1 of the MDMER in English and French
ECCC posts the summaries and full documents on the Government of Canada website for consultation.
Proponents must participate in the consultation sessions or meetings with Indigenous communities and the public. The proponent’s role is to explain the process followed in the assessment of alternatives, justify the selected alternative, and explain the proposed compensatory measures set out in the fish habitat compensation plan.
ECCC and DFO are also present at the consultation sessions. ECCC is responsible for explaining the regulatory process and associated consultation timelines. DFO describes their Department’s role and responsibilities in relation to its assessment of the FHCP.
The time required to complete consultations may vary depending on various factors, including the:
- amount of time Indigenous communities and interested parties need to engage, and provide comments, and
- time required for ECCC to respond to these comments in collaboration with the mine proponent and DFO.
2.4 Required documentation from the proponent
To proceed with regulatory development, the proponent will be required to submit the following to ECCC:
- all maps and diagrams in English and French
- a map that shows the location of the project (see Figure 2 in APPENDIX A for an example)
- a map showing the locations of the water bodies to be listed in Schedule 2 of the MDMER (see Figure 3 in APPENDIX A)
- a map showing the polygons must be provided (see Figure 4 in APPENDIX A) if a polygon approach is deemed to be the best to list water bodies in Schedule 2 of the MDMER
- a map showing the locations of the projects included in the fish habitat compensation plan
- a description of the water bodies that could be impacted by the disposal of mine waste, with a description of the fish habitat in those water bodies
- the geographic coordinates (latitude and longitude) of the water bodies to be listed in Schedule 2 of the MDMER (see APPENDIX A for examples of how water bodies are listed when listed in Schedule 2 of the MDMER)
- the total area of water bodies frequented by fish that will be impacted by the disposal of mine waste
- a detailed report of all consultations organized by the proponent with local communities and Indigenous communities impacted by the project in relation to the AA report and the FHCP. To the extent possible, include a list of responses to the comments received and demonstrate how these comments were incorporated into the development of the AA and the FHCP
2.5 Conditions for regulatory amendment
The following conditions must be met in order for the Minister of the Environment to recommend an amendment to Schedule 2 of the MDMER to the GIC.
- The applicable federal, provincial, and/or territorial environmental assessments for the project, if any, have been completed and approved by all relevant authoritiesFootnote 4
- An assessment of alternatives report for mine waste disposal has been prepared in accordance with ECCC’s Guidelines for the assessment of alternatives for mine waste disposal, and includes input and addresses concerns identified by Indigenous communities and the public
- A Fish Habitat Compensation Plan:
- has been recommended by the Department of Fisheries and Oceans (DFO)
- includes input and addresses concerns identified by Indigenous communities and the public
- that meets the requirements of the MDMER
- Consultations on proposed amendments to Schedule 2 of the MDMER are consistent with requirements set out in the Cabinet Directive on Regulation. These include:
- Indigenous communities potentially impacted by the proposed amendments have been consulted, and, where appropriate, accommodated
- Public and stakeholder consultations on the proposed amendments have been undertaken, and comments submitted have been considered and addressed
Note: An Order in Council exemption under section 24 of Transport Canada’s Canadian Navigable Waters Act may also apply to mining projects. It is the proponent’s duty to contact Transport Canada regarding potential impacts to navigation that may result from the prohibited activities, Order in Council exemptions, and related considerations for any navigable water associated with a planned mining development.
2.6 Governor in Council decision
Where the conditions in this document are met, the Minister of the Environment may recommend exemption from pre-publication in the Canada Gazette, Part I of regulatory amendments to designate certain water bodies as TIAs to the GIC. It is important to note that the decision to grant an exemption is made by the GIC on a case-by-case basis and that meeting these conditions does not guarantee that there will be an exemption from pre-publication. If approved by the GIC, these regulatory amendments would be exempt from pre-publication and be published as final in the Canada Gazette, Part II.
Per the Policy on Regulatory Development, a Regulatory Impact Analysis Statement (RIAS) will accompany any publication of regulatory amendments to Schedule 2 of the MDMER in the Canada Gazette, Part II. It will include a description of the TIA and the fish habitat compensation plan (including both associated costs and environmental impacts), and a summary of the consultations that took place.
2.7 Letter of credit or equivalent financial guarantee
If the GIC approves the proposed regulations, the proponent must then, pursuant to section 27.1 under subsection (3) of the MDMER, submit to DFO an irrevocable letter of credit or equivalent financial guaranteeFootnote 5 covering the costs of implementing the plan. The proponent is not permitted to release mine waste into water bodies listed in Schedule 2 of the MDMER until DFO has received the financial guarantee, and the final compensation plan has been approved by the Minister of Environment on the recommendation of DFO.
3.0 Timeline
It can take 6 to 12 months from the conclusion of Indigenous and public consultations to obtain the GIC decision on proposed Schedule 2 amendments to the MDMER. This is contingent on the Conditions for Regulatory Amendment outlined in Section 2.5 of this Guide being fulfilled.
An exemption from pre-publication does not diminish environmental protection. The conditions for regulatory approval found in this guide are intended to reduce approval timelines and reduce administrative burden.
Figure 1: Overview of the regulatory process for amendments to Schedule 2 of the MDMER

Long description
This figure is a flowchart that describes the steps and actions the proponent, ECCC, Governor in Council and the Minister of the Environment must take during the regulatory process of adding a fish frequented water body to Schedule 2 of the MDMER. The steps are as follows:
- The proponent submits options for mine waste disposal (proposed assessment of alternatives [AA] report) which ECCC reviews to ensure the report is developed in accordance with the Guidelines. Once it has been determined that the report has been developed in accordance with the Guidelines, it will be ready for public and Indigenous consultations. The proponent must also submit measures to offset for loss of fish habitat (proposed fish habitat compensation plan [FHCP]). If the FHCP is deemed adequate, DFO will recommend it to ECCC prior to ECCC proceeding with consultations
- ECCC holds consultations with Indigenous communities to get comments on the AA report and FHCP, receives and addresses comments and concerns. The proponent must participate in the meetings with ECCC and DFO
- ECCC reviews all regulatory development information and conditions and prepares materials for regulatory amendment. If all conditions are satisfied, the Minister of the Environment makes a recommendation to the GIC to amend Schedule 2 of the MDMER
- The Governor General makes a decision on the final regulatory amendments to Schedule 2 of the MDMER to designate waters frequented by fish as TIA, and its publication in Canada Gazette, Part II
- The proponent must meet conditions in section 27.1 of the MDMER. This includes submitting a FHCP that has been recommended by DFO. The proponent must also issue a financial guarantee to cover the cost of implementation of the FHCP
- Minister of the Environment shall approve the FHCP if requirements are met
- Lastly, the proponent may then use the waters frequented by fish for mine waste disposal
The timeline to obtain the GIC decision on a proposed Schedule 2 amendment is 6 to 12 months following the completion of consultations.
The timeline to obtain the Minister of Environment’s authorization on the compensation plan depends on the time required by the proponent to submit all documents for compliance with the MDMER section 27.1.
4.0 For more information
You may contact us by mail, at the following address:
Environment and Climate Change Canada
Metal and Diamond Mining Effluent Section
Mining and Processing Division
351 Saint-Joseph Boulevard,
Gatineau QC K1A 0H3
You can also send your comments and questions to the following email address: MDMER-REMMMD@ec.gc.ca.
APPENDIX A: Examples of water bodies listed in Schedule 2 of the MDMER
As described in the regulatory development process section, the geographic coordinates of water bodies to be added to Schedule 2 of the MDMER are required. The way in which water bodies are identified is different if reference is made to a lentic water body (that is, calm water such as lakes and ponds) or a lotic water body (that is, flowing water such as streams).
There are two options for describing a water body that is to be added to Schedule 2 of the MDMER:
Individual listing of water bodies
This approach is recommended when dealing with individual water bodies and/or water bodies that are geographically isolated from other water bodies. There are two ways to identify individual water bodies based on their type.
- A lentic environment such as a lake is identified by GPS coordinates for the middle of the water body
- Example for a lentic environment such as a pond (corresponds to the map shown in Figure 2): East Beaver Pond, located at 47°32′19.24″ north latitude and 81°55′14.03″ west longitude, approximately 20 km from the community of Gogama, Ontario
- A lotic water body such as a river is identified by GPS coordinates for each end
- Example for a lotic water body such as a river (corresponds to the map shown in Figure 3): A tributary of an unnamed lake, located approximately 20 km from the community of Gogama, Ontario. More precisely, the portion of the tributary extending southeast from the point located at 47°31′31.54″ north latitude and 81°54′57.84″ west longitude extending downstream to the point located at 47°31′20.35″ north latitude and 81°54′43.63″ west longitude
Polygon listing
This approach can be used when there are several water bodies to be added to Schedule 2 of the MDMER and they are clustered in a common area that can be delineated by a geographic zone or polygon.
Example of a polygon listing (corresponds to the map shown in Figure 4):
The waters located within an area located approximately 150 km north of Baker Lake, Nunavut. More precisely, the area bounded by five straight lines connecting five points starting at the point located at 65°40′45.1” north latitude and 96°67′58.5″ west longitude to the point located 778 m to the northwest at 65°41′05.6″ north latitude and 96°68′42.2″ west longitude to the point located 173 m northeast at 65°41′16.2″ north latitude and 96°68′15.2″ west longitude to the point located 1050 m southeast at 65°40′60.6″ north latitude and 96°66′32.7″ west longitude to the point located 168 m southeast at 65°40′45.8″ north latitude and 96°66′26.9″ west longitude and ending at the point located 611 m west at 65°40′45.1″ north latitude and 96°67′58.5″ west longitude.
Figure 2: Example of a map showing the project location

Long description
This figure is a map that shows an example project and its location defined by coordinates located at 47°32′19.24″ north latitude and 81°55′14.03″ west longitude, approximately 20 km from the community of Gogama, Ontario. The figure contains the following information:
- Gridlines showing longitude and latitude
- A rectangular legend at the bottom of the figure that contains map information including:
- a yellow star to show the location of the project site
- a yellow circle is used for regional communities
- brown line for major roads
- black lines with hashes for railway
- Black lines that delineate lower tier and upper tier municipality boundaries
- Orange polygon for a First Nation Reserve
- Brown polygon for a conservation reserve
- yellow polygon for a Provincial Park
- Blue polygon for waterbody or large watercourse
- Green shade for a wooded area
- The name of the owner/operator called IAMGOLD and the name of the project called Côté Gold Project
- The scale of the map which is 1:1,450,000
- A distance ruler from 0 to 100 kilometres
- The project registration number
- date of the map
- A compass rose
- Above the legend is a map that shows the region surrounding the project site which includes the communities of Sudbury, Elliot Lake, Timmins, and Kirkland Lake
- A smaller map is inserted in the top left corner of the figure that shows that an area of Ontario near Sudbury has been enlarged
Figure 3: Example of a map showing individual water bodies (in green) to be added to Schedule 2 of the MDMER

Long description
This figure is a map that identifies the individual water bodies to be added to Schedule 2 of the MDMER as part of an example mine site. The map shows the project area and surrounding lakes and roads. The project area shows where proposed mine infrastructure will overprint water bodies. There are five water bodies highlighted in green to be listed in Schedule 2 of the MDMER. The figure contains the following information:
- Gridlines showing longitude and latitude
- Green lines to delineate Schedule 2 waterbodies
- A pink circle to show a Schedule 2 water body endpoint
- Grey polygon to show the mine site footprint
- Green line for proposed haul road
- Blue segmented line for proposed potable water pipeline
- Black line for proposed power line
- Grey segmented line for proposed seepage collection ditch
- Pink line for proposed Highway 11 alignment
- Yellow line to show existing Highway 11
- Double green line to show major roads
- Blue line to show a watercourse
- Dark blue border that wraps a light blue polygon to show a waterbody
- Green polygon filled with horizontal lines to show a wetland that is eco-site based
- Green polygon filled with vertical lines to show a wetland that is unevaluated
Figure 4: Example of a map showing a polygon grouping together multiple water bodies to be added to Appendix 2 of the MDMER

This figure is a map that illustrates multiple water bodies that are grouped together to form a polygon listing to be added to Appendix 2 of the MDMER. The example map shows an area of a mine site containing one large water body with a watercourse that flows into a nearby smaller waterbody, two additional smaller waterbodies connected by a watercourse, with an additional watercourse that connects to the smallest waterbody. These four waterbodies and three watercourses are contained within a polygon area drawn by five straight lines connected by five points. Each point of the polygon is labelled (P1, P2, P3, P4 and P5). The map shows the location of mine infrastructure that will impact the waterbodies and watercourses within the polygon. The map contains the following information:
- Gridlines showing longitude and latitude
- A North arrow in the top right corner
- A rectangular legend at the bottom left of the figure that contains map information including:
- Bold blue lined polygon to show an alternative assessment lake
- light blue polygon to show a waterbody
- Solid blue line to show a waterway or watercourse
- Black bordered polygon with diagonal black and white stripes to show expansion project infrastructure
- Black bordered polygon with dark grey fill to show waste rock storage facility
- Black bordered polygon filled with light grey diagonal lines to show attenuation pond
- A distance ruler from 0 to 200 metres
- Map information including the GIS number, map date, and the projection which is NAD 1983 CSRS UTM Zone 14N
APPENDIX B: Proponent’s responsibilities
Summary of information to be submitted to ECCC by the proponent
Documents required from the proponent to meet the MDMER requirements:
- fish habitat compensation plan
- assessment of alternatives report
Documents required from the proponent for the consultations:
- a general overview of the project in English and French
- a plain language summary of the compensation plan that includes the information required under section 27.1 of the MDMER in English and French
- a plain language summary of the assessment of alternatives report in English and French
ECCC encourages proponents to provide copies of the summaries, as well as the full AA and FHCP reports, to local libraries in the affected communities for the public consultation period.
To support the regulatory development process, the proponent is required to submit the following to ECCC:
- all maps and diagrams in English and French
- a map showing the location of the project
- a map showing the locations of the water bodies to be added to Schedule 2 of the MDMER
- a map showing the locations of the projects included in the fish habitat compensation plan
A description of:
- water bodies that could be impacted by mine waste disposal
- fish habitat in those water bodies
- the geographic coordinates (latitude and longitude) of the water bodies to be added to Schedule 2 of the MDMER
- the total area of water bodies frequented by fish that will be impacted by mine waste disposal
- a report on the consultations conducted by the proponent during the development of the FHCP and the AA
- letter of credit or equivalent financial guarantee
This letter must identify the Receiver General of Canada as the beneficiary on behalf of DFO. The proponent must send this letter of credit to DFO. ECCC must be informed when this irrevocable letter of credit is submitted to DFO. Please contact DFO for further instructions.
APPENDIX C: useful links
Environment and Climate Change Canada – MDMER information
Page details
- Date modified: