Current Status

Notice of opportunity to provide input.

Project summary

The Rock Lake Mine (AMIS #07781) is a former gold, silver and copper mine that operated from 1899 to 1903. The mine is located off Highway 638, in the Township of Plummer Additional, approximately 16 kilometres north of Bruce Mines, Ontario.

The mine property can be divided into a northern area accessed by a private trail and a southern area accessed via a residential driveway.

The purpose of the project is to rehabilitate the mine hazards located in the northern portion of the mine, referred to here as Rock Lake Mine North.

Mine hazards include:

  • a shaft
  • two raises
  • a stope to surface
  • multiple crown pillars

The mine openings to surface are all currently flooded with no egress provided.

The proposed rehabilitation strategy for all mine workings is to backfill. Access will be provided by an existing roadway off Highway 638, with limited access improvements required. Some tree removal may be needed to facilitate the placement of the backfill.

The work is expected to occur over several months, during the fall of 2025, outside of the active period for bats and birds.

Proponent

Ministry of Mines

Location

Township of Plummer Additional, Algoma District

Type

Bulletin

Reference number

Environmental Registry of Ontario number: 025-0069

Contact

Emilie Trottier, Environmental Planner
Mine Rehabilitation Section
933 Ramsey Lake Road
Sudbury, Ontario
P3E 6B5
Telephone: 249-885-3631 
Email: Emilie.Trottier@ontario.ca

Notice of opportunity to provide input on a category B project (2023)

We invite you to comment on the Rock Lake Mine North Rehabilitation Project.

The proposed rehabilitation activities have been screened as a category B project with low potential for environmental effects. The undertaking is being carried out in accordance with the Class Environmental Assessment for Activities of the Ministry of Northern Development and Mines under the Mining Act (PDF, amended 2018).

We have identified environmental effects associated with the undertaking, which can be mitigated using standard measures. A summary of negative environmental effects and proposed mitigation measures that would negate or reduce their significance is provided in the project description, which you can find with the supporting material for this project on the Environmental Registry of Ontario.

We invite you to provide input and express any concerns about this proposed project. For more information, or to submit comments, visit the posting for this project on the Environmental Registry of Ontario or contact:

Emilie Trottier, Environmental Planner
Mine Rehabilitation Section
933 Ramsey Lake Road
Sudbury, Ontario
P3E 6B5
Telephone: 249-885-3631 
Email: Emilie.Trottier@ontario.ca

Your privacy

Personal information you provide in a submission (such as name, address and telephone number) and your views and opinions are being collected by the ministry under the authority of the Environmental Assessment Act for the purpose of engaging in public consultation and making decisions regarding the project.

Your personal information may also be shared with the Environmental Approvals Branch of the Ministry of the Environment, Conservations and Parks. The collection, use and disclosure of this information are all governed by the Freedom of Information and Protection of Privacy Act.

Questions about the collection of this information should be directed to:

Emilie Trottier, Environmental Planner
Mine Rehabilitation Section
933 Ramsey Lake Road
Sudbury, Ontario
P3E 6B5
Telephone: 249-885-3631 
Email: Emilie.Trottier@ontario.ca

Statement of completion

We have completed our assessment for the proposed rehabilitation of mine hazards at the former Rock Lake Mine (AMIS #07781). The mine is located off Highway 638, in the Township of Plummer Additional, approximately 16 kilometres north of Bruce Mines, Ontario. The property has been divided into a northern portion accessed by a private trail and a southern area accessed through a residential driveway.

The purpose of the project is to rehabilitate mine hazards located in the northern portion of the Rock Lake Mine, herein referred to as Rock Lake Mine North. The mine is situated on private land owned by a surface rights owner, while the Crown holds the minerals rights. The mine features several hazards including:

  • a shaft
  • two raises
  • a stope to surface
  • multiple crown pillars

All mine openings to the surface are currently flooded, with no egress available. The proposed rehabilitation strategy is to backfill. The backfill will allow the mine hazards to be closed-out in accordance with the Mine Rehabilitation Code of Ontario, while preserving the recreational value of the property for the surface rights owner.

We assessed this undertaking as a Category B, in accordance with the Class Environmental Assessment for Ministry of Northern Development and Mines Activities under the Mining Act (PDF) (Class EA).

Consultation summary

We distributed consultation letters to government agencies, Indigenous Communities and other interested persons on March 24, 2025. In addition, a Notice of Opportunity to Provide Input was posted as a bulletin notice on the Environmental Registry of Ontario (ERO #019-7004), and additionally referenced on the Mining Act resources webpage. The notice and letters were supported with a description of the project that included a summary of potential negative environmental effects associated with the undertaking and proposed mitigation measures that would negate or reduce the significance of the environmental effects. All parties consulted were given the opportunity to provide input and express concerns related to the project over a 30-day comment period.

No concerns were identified from the government ministries consulted.

The surface rights owner has informed us that the property will be used for a hunt in November 2025. To accommodate this, we will schedule the rehabilitation work to avoid any conflict with the planned hunt. We will maintain ongoing communication with the surface rights owner throughout the completion of the work.

No other comments were received that would affect the project as it is currently planned. We will implement the project as described in the project documentation.

Approved by:

May 8, 2025

Marc Stewart
Senior Manager, Mine Rehabilitation Section
933 Ramsey Lake Road
Sudbury, Ontario
Telephone: 705-670-5798 
Email: marc.stewart@ontario.ca