Guidelines for the assessment of alternatives for mine waste disposal: chapter 1

1 Guidance for Proponents on the Federal Process for Designating Metal Mine Tailings Impoundment Areas

1.1 Context

It is expected that natural water bodies frequented by fish shall be avoided to the extent practicable for the long-term disposal of mine waste; and that mine waste shall be managed to ensure the long-term protection of Canada's terrestrial and aquatic environment.

Using a natural water body frequented by fish for mine waste disposal requires an amendment to the Metal Mining Effluent Regulations (MMER), which is a federal legislative action. The MMER, enacted in 2002, were developed under subsections 34(2), 36(5) and 38(9) of the Fisheries Act to regulate the deposit of mine effluent, waste rock, tailings, low-grade ore and overburden into natural waters frequented by fish. These regulations, administered by Environment Canada, apply to both new and existing metal mines. Schedule 2 of the MMER lists water bodies designated as tailings impoundment areas (TIAs). A water body is added to that Schedule through a regulatory amendment.

1.2 Purpose

These guidelines describe the process that must be undertaken when a proponent is considering using a natural water body frequented by fish as a TIA such that a regulatory amendment to the MMER would be required.  In the context of these guidelines, the term TIA refers to a natural water body frequented by fish into which deleterious substances (such as tailings, waste rock, low-grade ore, overburden, and any effluent that contains any concentration of the deleterious substances specified in the MMER, and of any pH) are disposed.

Waste rock, low-grade ore, and overburden

Metal mine waste rock, low-grade ore and overburden may be deleterious, in which case disposing them in a water body would require that the water body first be listed on Schedule 2 of the MMER as a TIA.

If the proponent can demonstrate that they are not deleterious, then no Schedule 2 listing would be required.

For more information on deleterious substances please see Annex 1.

These guidelines pertain to metal mines where a TIA has been proposed in a natural water body frequented by fish. However, the requirements for the conduct of alternatives assessments that are presented in Part 2 provide useful guidance for the assessment of all mine waste disposal areas including those developed on land. The overall objective of the alternatives assessment process is to minimize the environmental footprint of the disposal area.

1.3 Environmental Assessment

A project which includes a proposal to use a natural, fish-frequented water body for the disposal of mine waste triggers a requirement for a federal environmental assessment (EA) under the Canadian Environmental Assessment Act (CEAA), where applicable. Proposals may also be subject to additional provincial and land claim based EA obligations such as those outlined under the Inuvialuit Final Agreement for the Inuvialuit Settlement Region of the Northwest Territories.

For projects in the Yukon, Nunavut and the MacKenzie Valley portion of the Northwest Territories where CEAA does not apply, EA requirements are met through other federal and territorial regimes.

Proposals may also be subject to provincial EA obligations.

An Environment Canada policy, which was developed in conjunction with the repeal of the Alice Arm Tailings Deposit Regulations when the MMER were registered in 2002, recommends against unconfined tailings disposal in the sea.

1.3.1 Overview

A mining project that includes a proposal to use a natural water body frequented by fish as a TIA must undergo an EA and the project proponent must also:

  • prepare an assessment of alternatives for mine waste disposal for consideration (see Part 2 of these Guidelines);
  • prepare a fish habitat compensation plan for consideration as part of the EA; and
  • participate in public and aboriginal consultations on the EA, including on possible amendments to the MMER.1

Details of the EA process vary depending on the legislation or land claim under which the EA is conducted and the type of EA conducted. The project proponent needs to verify which EA regime applies (e.g., screening, comprehensive study or review panel for EAs conducted under the CEAA). The Canadian Environmental Assessment Agency has resources to help guide proponents through the federal EA process under the CEAA.

In preparing the documentation for the EA, the proponent should take into consideration the requirements of the Cabinet Directive on Regulatory Management (CDRM). While the CDRM does not apply to proponents directly, it is a requirement of the regulatory process and it is strongly recommended that the proponent help lay the necessary groundwork to carry out a cost-benefit analysis in respect of the CDRM. More specifically, the necessary regulatory action should be demonstrated to maximize net benefits for society through an assessment of impacts as well as the distributional implications.

The proponent should also take into consideration the recommendations in Environment Canada’s Environmental Code of Practice for Metal Mines during the EA. The Code supports the MMER, but also covers a broad spectrum of environmental aspects that extend well beyond it.

1.3.2 Assessment of alternatives

A project proponent seeking to use a natural water body as a TIA must conduct an assessment of alternatives for mine waste disposal. It is strongly recommended that this assessment be undertaken during the EA to streamline the overall regulatory review process and minimize the time required to proceed with the MMER amendment process. Generally speaking, at least one of these alternatives should not impact a natural water body that is frequented by fish. It is important to note that a decision by the proponent to conduct the alternatives assessment after the EA has been completed could more than double the target timeline that has been established for the processing of Schedule 2 amendments.

This alternatives assessment must objectively and rigorously assess all feasible options for mine waste disposal. The project proponent must demonstrate through the EA and this assessment that the proposed use of the water body as a TIA is the most appropriate option for mine waste disposal from environmental, technical and socio-economic perspectives. It should also be demonstrated that the option offers the greatest overall benefit to current and future generations of Canadians, as per the CDRM. Part 2 describes the requirements of an assessment of alternatives.

1.3.3 Fish habitat compensation plan

Section 27.1 of the MMER requires the project proponent to develop and implement a fish habitat compensation plan to offset the loss of fish habitat that would occur as a result of the proposed addition of a water body to Schedule 2. The proposed plan must be submitted during the EA for consideration as part of the EA. The plan must describe, among other things:

  • fish habitat that would be lost as a result of the proposed TIA;
  • compensation measures that would be implemented, if approval is given to use the water body as a TIA, to offset the loss of fish habitat that would result;
  • plans to monitor the implementation of the compensation plan; and
  • a breakdown of estimated costs for implementation and monitoring of the plan.

See Practioner’s Guide to Habitat Compensation.

If the Governor in Council approves the regulation adding the water body as a TIA in Schedule 2, then, as per Section 27.1 of the MMER, the proponent must submit to DFO an irrevocable letter of credit to cover the plan’s implementation costs.

The proponent must also develop and implement a fish habitat compensation plan under subsection 35(2) of the Fisheries Act to offset the harmful alteration, disruption or destruction of fish habitat as a result of the works needed for constructing the TIA. See Annex 2 for an explanation as to why two fish habitat compensation plans are needed.

1.3.4 Consultations

During the EA, Environment Canada and DFO consult local and national stakeholders and representatives of Aboriginal peoples to ensure that all interested parties have access to information about the project and have the opportunity to provide input and comments. The project proponent participates in the consultations to directly communicate the results of their alternatives assessment and its conclusions to all engaged parties.

Consultations on the proposed MMER amendment are conducted in accordance with the Treasury Board Guidelines for Effective Regulatory Consultations.

DFO leads any additional Aboriginal consultations to ensure that all obligations that may exist in relation to rights protected by section 35 of the Constitution Act, 1982 have been satisfied. Guidance on these consultations may be informed in part by the consultations undertaken pursuant to the alternatives assessment.

1.3.5 EA decision

The application for a TIA following the EA decision can only proceed to the regulatory stage if the decision taken pursuant to the environmental assessment is that the project can be carried out, in whole or in part, past the EA stage. If the government decision is that the project should not proceed, no further action is taken with respect to the possible MMER amendment.

1.4 Regulatory Process

The decision to add a water body to Schedule 2 of the MMER is made by Treasury Board. Key elements needed for the regulatory process (assessment of alternatives, fish habitat compensation plan) take place during the EA phase, described above. The next steps in the regulatory process are:

  1. Environment Canada prepares the regulatory amendment package to move forward with the TIA listing on Schedule 2 of the MMER. The package includes the text of the proposed regulatory amendment, which provides the name and geographical description of the water body being proposed as a TIA. The package also includes a Regulatory Impact Analysis Statement (RIAS) which is a key document in justifying the proposed Schedule 2 amendment. It includes, among other things:
    • a description of the project;
    • the rationale for the proposed amendment;
    • a summary of the proposed fish habitat compensation plan;
    • a description of the options that are considered during the alternatives assessment evaluation;
    • a summary of the consultations; and
    • a cost-benefit analysis of the proposed amendment, which assesses potential impacts from a broad societal perspective (e.g., environment, businesses, consumers, and other sectors of society). A key element of the cost benefit analysis is the development of a baseline and regulatory scenario. Cost information related to the alternatives assessment as well as costs related to the fish habitat compensation plan are included in this analysis. For more information, see Annex 3 and also the Treasury Board of Canada Secretariat Guide to the Regulatory Process.
  2. If approved by the Ministers of Environment and Fisheries and Oceans, the regulatory amendment package is sent to the Treasury Board for consideration.
  3. If approved by the Treasury Board, the proposed amendment is published in Part I of the Canada Gazette for a 30-day public comment period.
  4. 30-day public comment period.
  5. Review of comments received.
  6. Environment Canada prepares the final regulatory package, with the final RIAS incorporating responses to the comments received.
  7. Submission of the final regulatory package to the Ministers of Environment and Fisheries and Oceans for approval to submit the regulatory amendment to the Treasury Board.
  8. If approved by the Treasury Board, the regulatory amendment becomes law and is registered.
  9. The regulatory amendment and the RIAS are published in Part II of the Canada Gazette, approximately two weeks after being registered.

These steps conform to the requirements of the CDRM.

Annex 4 provides a flow chart of the key steps in the EA and regulatory processes.

1.4.1 Timing

The regulatory amendment process typically takes 8-12 months after the end of the EA. However, if additional information is required (e.g., data gaps, missing cost information about the TIA or fish habitat compensation plan, etc.) or if there is litigation, the process could be longer.

For major resource projects, target timelines for the EA and regulatory processes are publicly tracked and monitored by the Major Projects Management Office.

1.4.2 Other Fisheries Act authorizations

Where subsection 35(2) Fisheries Act authorizations (regarding the harmful alteration, disruption or destruction of fish habitat) associated with the construction of the TIA is granted, this occurs after the Schedule 2 amendments are completed, typically no later than three weeks following listing.

However, subsection 35(2) authorizations that are not related to the construction of the TIA could be issued prior to the Governor in Council decision on the Schedule 2 amendment.

1.5 Getting started

Proponents of metal mines south of 60° are encouraged to contact the Major Projects Management Office and, for mines north of 60°, the Northern Projects Management Office. The offices provide overarching project coordination, management, project tracking and guidance to proponents.


1 If the proposed use of a natural water body as a TIA would impact navigable water, then an Order in Council approval is also required under the Navigable Waters Protection Act. In such cases, Transport Canada is involved in the EA, and would be involved in the regulatory process for the proposed TIA, in the event that the regulatory process is undertaken.


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