Metal and Diamond Mining Effluent Regulations (SOR/2002-222)

About the Regulations

The Metal Mining Effluent Regulations were amended in 2018, and are now known as the Metal and Diamond Mining Effluent Regulations (MDMER).

The MDMER authorize the deposit of effluent into fish frequented waters. All effluent must meet the concentration-based limits for arsenic, copper, cyanide, lead, nickel, zinc, suspended solids and radium 226. Also, the effluent must have a pH that is between a minimum and maximum level, and it must not be acutely lethal. The MDMER specify various requirements such as carrying out effluent sampling, reporting and Environmental Effects Monitoring.

The MDMER also include authorizations for the use of waters frequented by fish for mine waste disposal. This can only be authorized through an amendment to Schedule 2 of the MDMER and when certain conditions are met. Owners or operators of mines can request an amendment to Schedule 2 of the MDMER, which would designate a waterbody frequented by fish as a Tailings Impoundment Area.

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Metal Mining Effluent Regulations compliance data

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Mining and Processing Division
Environment and Climate Change Canada
351 Saint-Joseph Boulevard
Gatineau QC K1A 0H3
Email: ec.mdmer-remmmd.ec@canada.ca

Read the Regulations

The Metal Mining Effluent Regulations were amended in 2018, and are now known as the Metal and Diamond Mining Effluent Regulations (MDMER).  

The MDMER authorize the deposit of effluent into fish frequented waters. All effluent must meet the concentration-based limits for arsenic, copper, cyanide, lead, nickel, zinc, suspended solids and radium 226. Also, the effluent must have a pH that is between a minimum and maximum level, and it must not be acutely lethal. The MDMER specify various requirements such as carrying out effluent sampling, reporting and Environmental Effects Monitoring.

The MDMER also include authorizations for the use of waters frequented by fish for mine waste disposal. This can only be authorized through an amendment to Schedule 2 of the MDMER and when certain conditions are met. Owners or operators of mines can request an amendment to Schedule 2 of the MDMER, which would designate a waterbody frequented by fish as a Tailings Impoundment Area.

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Enabling Act: Fisheries Act

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The Metal Mining Effluent Regulations were amended in 2018, and are now known as the Metal and Diamond Mining Effluent Regulations (MDMER).  

The MDMER authorize the deposit of effluent into fish frequented waters. All effluent must meet the concentration-based limits for arsenic, copper, cyanide, lead, nickel, zinc, suspended solids and radium 226. Also, the effluent must have a pH that is between a minimum and maximum level, and it must not be acutely lethal. The MDMER specify various requirements such as carrying out effluent sampling, reporting and Environmental Effects Monitoring.

The MDMER also include authorizations for the use of waters frequented by fish for mine waste disposal. This can only be authorized through an amendment to Schedule 2 of the MDMER and when certain conditions are met. Owners or operators of mines can request an amendment to Schedule 2 of the MDMER, which would designate a waterbody frequented by fish as a Tailings Impoundment Area.

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