Status report on the performance of mines subject to the Metal and Diamond Mining Effluent Regulations in 2023

A summary of effluent releases of final discharge points for metal and diamond mines located in Canada.

Executive summary

This report presents a summary of the performance of Canadian mines in 2023 with respect to the prescribed limits and requirements of the Metal and Diamond Mining Effluent Regulations (Regulations). The annual report provides information on:

• mines subject to the Regulations
• effluent data
• compliance performance
• water bodies designated as tailings impoundment areas

Approval for release does not signify that the content reflects the views and policies of Environment and Climate Change Canada (ECCC).

The owners and operators of mines provided the statistics contained in this report to ECCC. The Regulations require that owners or operators report information to ECCC, including:

• concentrations for deleterious substances including metals, cyanide, suspended solids, and un-ionized ammonia
• pH of effluent
• effluent volume
• summary results of acute lethality tests

ECCC compiled the compliance statistics presented in this report. They are based on the information provided in monitoring report submissions and do not include unreported data.

In 2023, 4 diamond mines and 147^{Footnote 1},^{Footnote 2} metal mines in Canada were subject to the Regulations. During the year, 3 mines became subject to the Regulations and 2 mines became a recognized closed mine. Four mines subject to the Regulations did not provide 1 or more monitoring reports. The total number of exceedances for deleterious substances and pH reported by mines was 136. For acute lethality tests, owners reported 21 failures for fish and 78 failures for invertebrate species.

Schedule 2 of the Regulations lists water bodies designated as tailings impoundment areas. In 2023, 4 waters or places were listed in Schedule 2 of the Regulations.

The report provides an explanation of the 2023 data sets published on the Government of Canada’s Open Data Portal.

ECCC enforces the Regulations in accordance with the Compliance and Enforcement Policy for the Habitat Protection and Pollution Prevention Provisions of the Fisheries Act.

For all purposes of interpreting and applying the law, users should consult the Regulations. Please consult the Metal and Diamond Mining Effluent Regulations, as registered by the Clerk of the Privy Council and published in Part II of the Canada Gazette.

More information on the Regulations is available on the Metal and diamond mining effluent webpage.

Acronyms and abbreviations

As

arsenic

Bq/L

Becquerel per litre

BC

British Columbia

CN

cyanide

Cu

copper

DM

Daphnia magna

ECCC

Environment and Climate Change Canada

FDP

final discharge point

ID

facility identification

m³

cubic metre(s)

MB

Manitoba

mg/L

milligram(s) per litre

NB

New Brunswick

NH₃

un-ionized ammonia

Ni

nickel

NL

Newfoundland and Labrador

NS

Nova Scotia

NT

Northwest Territories

NU

Nunavut

ON

Ontario

Pb

lead

QC

Quebec

Ra-226

radium 226

RT

rainbow trout

SK

Saskatchewan

SS

suspended solids

TIA

tailings impoundment area

YT

Yukon

Zn

zinc

List of tables

Table 1. Number of exceedances for deleterious substances and pH from 2014 to 2023

Table 2A. Performance summary: fish acute lethality tests in 2023, by region

Table 2B. Performance summary: invertebrate species acute lethality tests in 2023, by region

Table 3. Percentage of regulatory data within authorized limits from 2014 to 2023

Table 4.  Number of notifications submitted in 2023, by region

Table A1. Exceedance summary for mines subject to the Regulations in 2023: prescribed parameters and pH

Table A2. Exceedance summary for mines subject to the Regulations in 2023: acute lethality tests

List of figures

Figure 1. Number of mines subject to the Regulations from 2014 to 2023

Figure 2. Location of mines subject to the Regulations in 2023

Figure 3. Total number of exceedances for deleterious substances and pH, against number of mines from 2014 to 2023

1. Introduction

The Metal and Diamond Mining Effluent Regulations (Regulations) aim to reduce threats to fish, fish habitat, and the use of fish by humans by improving the management of deleterious substances in metal and diamond mining effluent.

Effluent must meet concentration-based limits for arsenic, copper, cyanide, lead, nickel, zinc, suspended solids, radium 226, and un-ionized ammonia. Effluent must have a pH that is between a minimum and maximum level and must not be acutely lethal. The Regulations require effluent testing and reporting, as well as environmental effects monitoring studies.

Owners and operators of mines subject to the Regulations must report information to ECCC, including effluent monitoring results. The statistics in this report are based on data provided to ECCC by the owners or operators of mines. These statistics do not include data that were not reported to ECCC.

The Regulations also include an authorization for the use of water frequented by fish for mine waste disposal if certain conditions are met. Authorization requires an amendment to Schedule 2 of the Regulations. Owners or operators of mines can request an amendment to Schedule 2 of the Regulations. This would designate a water frequented by fish as a tailings impoundment area.

For additional information, visit the Metal and Diamond Mining Effluent webpage.

2. Purpose

The purpose of this report is to summarize effluent quality data and compliance of mines subject to the Regulations, as reported to ECCC. This report also summarizes the water bodies that were newly designated as tailings impoundment areas under the Regulations. The report provides an explanation of the 2023 data sets published on the Government of Canada’s Open Data Portal. This report includes data reported to ECCC within the past 10 years, where appropriate, to support trends-based analysis.

ECCC compiled this summary to inform the regulated community, other stakeholders, and the public on the performance of mines subject to the Regulations. The material is for informational purposes only. For all purposes of interpreting and applying the law, users should consult the Regulations. The Metal and Diamond Mining Effluent Regulations are registered by the Clerk of the Privy Council and published in Part II of the Canada Gazette.

Approval for release does not signify that the content reflects the views and policies of ECCC.

3. Overview

3.1 Mines subject to the Regulations

A metal or diamond mine becomes subject to the Regulations when it:

• exceeds an effluent flow rate of 50 cubic meters per day, based on effluent deposited from all final discharge points of the mine
• deposits a deleterious substance in any water or place referred to in subsection 36(3) of the Fisheries Act

In 2023, 147^{Footnote 1},^{Footnote 2} metal and 4 diamond mines in Canada were subject to the Regulations.^{Footnote 3} Figure 1 shows the number of facilities subject to the Regulations from 2014 to 2023.^{Footnote 4}

Figure 1. Number of mines subject to the Regulations from 2014 to 2023

Figure 2 shows a map illustrating the locations of mines subject to the Regulations.

A list of mines subject to the Regulations is available on the Government of Canada’s Open Data Portal in the Identification Report document. This document includes the following information:

• the name of each mine subject to the Regulations
• the name of the owner and operator of each mine
• the geographic coordinates of each mine’s location

Please consult the Data Dictionary for additional information related to this document.

Figure 2. Location of mines subject to the Regulations in 2023

3.2 Mines with new regulatory status

Each mine subject to the Regulations is required to report information to ECCC until it becomes a recognized closed mine. Three mines became subject to the Regulations in 2023:

• Fayolle Mine in Quebec
• Mine Whabouchi in Quebec
• Project Akasaba in Quebec

Two mines became recognized closed mines in 2023:

• Max Mine in British Columbia
• Broken Hammer Mine Site in Ontario

3.3 Final discharge points

A final discharge point (FDP), in respect of an effluent, means an identifiable discharge point of a mine beyond which the operator of the mine no longer exercises control over the quality of the effluent. Mines are required to manage all their effluent and only to discharge effluent through FDPs.

A list of FDPs of mines subject to the Regulations is available on the Government of Canada’s Open Data Portal in the Final Discharge Points document. This document lists all the FDPs associated with each mine and their geographical coordinates.

4. Performance of mines

4.1 Reporting requirements

Owners or operators of mines subject to the Regulations are required to provide quarterly and annual monitoring reports until the mine becomes a recognized closed mine. Quarterly reports are due not later than 45 days after the end of the calendar quarter. Annual reports are due by March 31 of the following year.

Of the 151^{Footnote 1}, ^{Footnote 2} mines that are subject to the Regulations, 4 mines provided no quarterly or annual effluent monitoring reports in 2023:

• annual report not submitted:
  • Yellowjacket Gold Mine in British Columbia
• no reports submitted or some quarterly reports not submitted:
  • Lockerby Mine in Ontario
  • Edwards Mine in Ontario
  • Clavos Mine in Ontario

4.2 Prescribed deleterious substances and pH

The Regulations include provisions to allow the discharge of metal and diamond mine effluent into water frequented by fish, subject to certain requirements. The Regulations authorize the deposit of effluent that contains a deleterious substance if:

• the concentration of the deleterious substance in the effluent does not exceed the authorized limits^{Footnote 5}
• the pH of the effluent is equal to, or greater than, 6.0 but is not greater than 9.5^{Footnote 6}
• the effluent is not acutely lethal^{Footnote 7}

Owners and operators of mines are required to conduct regular monitoring of effluent and report information to ECCC. Reported information includes, for each FDP:

• concentrations for deleterious substances including metals, cyanide, suspended solids (SS), and un-ionized ammonia
• pH range of effluent
• effluent volume
• summary results of acute lethality tests

ECCC publishes effluent quality results, as reported by operators of mines, on the Government of Canada’s Open Data Portal. The frequency of testing varies depending on the individual mine and its performance. Under the Regulations, operators test the effluent at each FDP weekly for deleterious substances and monthly for acute lethality. The operator of a mine is required to record the results of all tests. The frequency of testing can be reduced to once per quarter in the following instances:

• for arsenic, copper, cyanide,^{Footnote 8} lead, nickel, zinc, and un-ionized ammonia: if the concentration of the substance from an FDP is less than 10% of the monthly mean concentration limit for that substance for 12 consecutive months
• for radium 226 from a mine, other than uranium mines: if the concentration of radium 226 is less than 0.037 Bq/L for 10 consecutive weeks
• for acute lethality: if the effluent is determined not to be acutely lethal for 12 consecutive months

For deleterious substances, ECCC compares the individual test results for each substance with the maximum authorized concentration in a grab or composite sample set out in the Regulations. All test results in a month for each substance are used to calculate monthly mean concentrations for each FDP. ECCC evaluates the performance by comparing the monthly mean concentrations to the maximum authorized monthly mean concentration limits set out in the Regulations. Those monthly mean concentrations reported to ECCC that are above the prescribed limits represent reported exceedances.

For pH, ECCC compared the individual test results for each grab sample with the prescribed range. ECCC evaluates performance by determining how many grab samples are within the prescribed range.

Figure 3 shows the total number of exceedances for deleterious substances and pH against the number of mines subject to the Regulations from 2014 to 2023.

Figure 3. Total number of exceedances for deleterious substances and pH, against number of mines from 2014 to 2023

Table 1 shows the number of exceedances for each of the deleterious substances and pH from 2014 to 2023. In 2023, there was an overall decrease in exceedances for several parameters such as arsenic, lead, nickel, un-ionized ammonia, and pH low compared to 2022.

Note: NA = Not applicable

Table A1 in Appendix A lists the following for 2023:

• the mines that reported an exceedance
• the number of exceedances that were reported for each of the prescribed deleterious substances and pH

4.3 Fish and invertebrate toxicity

The Regulations require that effluent be non-acutely lethal. Acute lethality refers to tests of effluent on mortality rate to fish (rainbow trout or threespine stickleback) and invertebrates (Daphnia magna or Acartia tonsa). The biological test methods publications web page provides more information on the methods prescribed by the Regulations to determine acute lethality.

Section 21 of the Regulations indicates that all test results are to be reported to ECCC. Tables 2A and 2B summarize the acute lethality tests results. Metal and diamond mines subject to the Regulations conducted a total of 1417 fish acute lethality tests. Of those tests, 10 mines reported 21 acute lethality tests that resulted in greater than 50% fish mortality. Mines also conducted a total of 1894 invertebrate acute lethality tests. Of those tests, 24 mines reported 78 tests with greater than 50% mortality.

In 2023, the total number of fish acute lethality tests with greater than 50% mortality decreased from 31 to 21 compared to 2022. During that time, the number of invertebrate acute lethality tests greater than 50% mortality also decreased from 313 to 78.

ECCC publishes the acute lethality test results as reported by operators of mines on the Government of Canada’s Open Data Portal. ECCC publishes the data in four separate files:

• rainbow trout acute lethality test results
• threespine stickleback acute lethality test
• Daphnia magna acute lethality test results
• Acartia tonsa acute lethality test results

* Regions are classified as follows: Atlantic region includes the provinces of New Brunswick, Newfoundland and Labrador, Nova Scotia, and Prince Edward Island. Pacific-Yukon region includes the province of British Columbia, and Yukon Territory. Prairie-Northern region includes the provinces of Alberta, Manitoba, Saskatchewan, the Northwest Territories, and the territory of Nunavut.

Table A2 in Appendix A lists the following for 2023:

• the mines that reported a failure for acute lethality tests
• the number of failures that were reported for each of the tests.

4.4 Summary of regulatory data

Table 3 shows the percentage of regulatory data within authorized limits for 2014 to 2023. Compared to 2022, the percentage of mining operations meeting regulatory standards for lead, nickel, un-ionized ammonia, pH low, and fish and invertebrate non-toxicity increased in 2023. For deleterious substances, compliance was 99% or higher for 7 substances and above 97% for the remaining substances.

Note: NA = Not applicable

4.5 Notifications

The owner or operator of a metal or diamond mine is required to submit notifications or information to the Minister of the Environment.  ECCC publishes the list of notifications on the Government of Canada’s Open Data Portal. Table 4 shows the notifications submitted to ECCC related to the following:

• Identifying information
• Final discharge points
• Reduced frequency
• End of commercial operation
• Intent to become or reopen recognized closed mines, and record keeping
• Recognized closed mines identification information

* Regions are classified as follows: Atlantic region includes the provinces of New Brunswick, Newfoundland and Labrador, Nova Scotia, and Prince Edward Island.  Pacific-Yukon region includes the province of British Columbia, and Yukon Territory. Prairie-Northern region includes the provinces of Alberta, Manitoba, Saskatchewan, the Northwest Territories, and the territory of Nunavut.

5. Water bodies designated as tailings impoundment areas

The Regulations authorize the deposit of mine waste (such as waste rock, tailings, and effluent) into a tailings impoundment area (TIA) that is either:

• a water or place set out in Schedule 2 of the Regulations; or
• a confined disposal area other than a disposal area that is or is part of a natural water body that is frequented by fish.

Tailings impoundment areas are listed in Schedule 2 via an amendment to the Regulations. Various requirements must be met before the Minister of the Environment can recommend the amendment to the Governor in Council. The proponent must demonstrate that the proposed option to use water bodies frequented by fish to dispose of mine waste is the best option from an environmental, technical, economic and socio-economic perspective. The proponent must also develop and implement a compensation plan to offset the loss of fish habitat. Additional information is available on the Tailings impoundment areas web page.

In 2023, Schedule 2 of the Regulations was amended to list 4 new waters or places as TIAs (item numbers 69, 70, 71 and 72). At the end of 2023, Schedule 2 contained 72 listings that are associated with 29 mines. A complete list of waters or places that have been designated as TIAs is available on the Government of Canada’s Open Data Portal.

Water or place listed on Schedule 2 of the Regulations in 2023

• mine name: Blackwater Project
  • province/territory: British Columbia
  • item number(s)^{Footnote 10} 69, 70, 71, 72
  • water or place: All waters located within the area described in column 2, located approximately 112 km southwest of Vanderhoof, British Columbia
  • link to Canada Gazette Part II publication

6. Compliance and enforcement

ECCC’s Enforcement Branch enforces the pollution prevention provisions of the Fisheries Act and accompanying regulations to protect and prevent harm to fish, fish habitat or human use of fish. ECCC enforces the Regulations in accordance with the Compliance and Enforcement Policy for the Habitat Protection and Pollution Prevention Provisions of the Fisheries Act. The policy sets out a range of possible responses to offences that can be used by enforcement officers. These include warnings, directions, ministerial orders, injunctions, prosecution and civil suits by the Crown for the recovery of costs. When there is evidence of an alleged violation, an enforcement officer considers the nature of the alleged offence, effectiveness in achieving the desired result with the alleged offender, and consistency in enforcement in order to determine the appropriate response.

In March 2023, ECCC implemented a recommendation from the Commissioner of the Environment and Sustainable Development audit report by upgrading its internal systems to account for all types of unauthorized deposits from mines under the Fisheries Act and Regulations. This facilitates the work of the enforcement officers responsible for ensuring compliance with the Fisheries Act and the regulations by tracking unauthorized deposits. In addition, the upgrade facilitates the work of monitoring and managing the risks associated with these events.

ECCC enforcement officers recorded 16 enforcement files with a suspected or confirmed unauthorized deposit from mines regulated under the Regulations at a place other than a final discharge point between April to December of 2023. Complete annual data will be available in future years but is not available for 2023 as the database updates occurred in March.

Appendix A: Performance summary of mine effluent not meeting effluent quality standards

This appendix summarizes the number of exceedances reported by operators of mines subject to the Regulations in 2023. Table A1 summarizes the distribution of the non-compliant parameters for prescribed deleterious substances and pH. Table A2 summarizes the results of acute lethality tests.

Prescribed deleterious substances exceedances represent the number of monthly mean concentrations that exceeded the prescribed limits for a given month. pH exceedances represent the number of pH range exceedances. The parameters included are arsenic (As), copper (Cu), cyanide (CN), lead (Pb), nickel (Ni), zinc (Zn), suspended solids (SS), radium 226 (Ra-226), un-ionized ammonia (NH₃), and pH.

Note: NA = Not Applicable

Appendix B: Regulatory data available on the Government of Canada’s Open Data Portal

ECCC publishes data submitted by operators of mines subject to the Regulations on the Government of Canada’s Open Data Portal. ECCC has developed a Data Dictionary that includes a list and description of the data fields included in the dataset. Please consult the Data Dictionary for additional information on the data published.

Listed below are the data files published on the Government of Canada’s Open Data Portal in the order they are included in the Annual Report by ECCC. Descriptions of the data contained in each file are listed as sub-bullet points.

• 2019-present MDMER identification report
  • Year
  • Facility identification (ID)
  • Facility name
  • Organization name
  • Design rated capacity (tonnes/year)
  • Rationale for design rated capacity
  • National Pollutant Release Inventory (NPRI)
  • Owner address - name
  • Operator address – name
  • Latitude
  • Longitude
• 2019-present MDMER final discharge points
  • Year
  • Facility ID
  • Facility name
  • Organization name
  • Final discharge point name
  • Latitude
  • Longitude
• 2019-present MDMER deleterious substance monitoring
  • Year
  • Facility ID
  • Facility name
  • Final discharge point name
  • Quarter
  • Final discharge point latitude
  • Final discharge point longitude
  • Collection date
  • Collection method
  • Failed acute lethality test?
  • Total effluent volume deposited, m³
  • Concentration, in mg/L, of:
    • Arsenic
    • Copper
    • Cyanide
    • Lead
    • Nickel
    • Zinc
    • Suspended solids
  • Concentration, in Bq/L, of Radium 226
  • Concentration, in mg/L, expressed as Nitrogen (N), of un-ionized ammonia
  • pH value
• 2019-present MDMER rainbow trout acute lethality
  • Year
  • Facility ID
  • Facility name
  • Final discharge point
  • Region
  • Quarter
  • Sample date time
  • Observed concentration %v/v
  • Mean mortality number 96^th hour
  • Mean stressed number 96^th hour
  • Mean mortality rate 96^th hour %
  • Mean stressed rate 96^th hour %
• 2019-present MDMER threespine stickleback acute lethality
  • Year
  • Facility ID
  • Facility name
  • Final discharge point
  • Region
  • Quarter
  • Sample date time
  • Observed concentration %v/v
  • Mean mortality number 96^th hour
  • Mean stressed number 96th hour
  • Mean mortality rate 96^th hour %
  • Mean stressed rate 96^th hour %
• 2019-present MDMER Daphnia magna acute lethality
  • Year
  • Facility ID
  • Facility name
  • Final discharge point
  • Region
  • Quarter
  • Sample date time
  • Observed concentration %v/v
  • Mean mortality number 48^th hour
  • Mean stressed number 48^th hour
  • Mean mortality rate 48^th hour %
  • Mean stressed rate 48^th hour %
• 2022-present MDMER Acartia tonsa acute lethality
  • Year
  • Facility ID
  • Facility name
  • Region
  • Quarter
  • Final discharge point
  • Was effluent deposited in the calendar quarter?
  • Sample ID
  • Salinity value of the effluent (ppt)
  • Reporting frequency
  • Sample date time
  • Percentage mortality in 100% effluent test concentration
• 2019-present MDMER Schedule 2
  • Year added to Schedule 2
  • Mining facility name
  • Province or territory
  • Item #
  • Water or Place
  • Link to Canada Gazette Part II publication (English)
  • Link to Canada Gazette Part II publication (French)
• 2023-present-MDMER-Notification-list
  • Year
  • Facility ID
  • Facility name
  • Final discharge point
  • Region
  • Province or territory
  • Provision of MDMER
  • Notification name
  • Submission date