List of Abandoned Mining Sites

The following paragraphs provide details of the main steps in the management of abandoned mining sites taken over by the Ministère de l’Énergie et des Ressources naturelles (MERN).


Acid mine drainage

Outflow of acidic water containing dissolved metals produced by oxidation of sulphide minerals contained in waste rock, ore and mine tailings following exposure to air and water.

Contaminated neutral drainage

Outflow of water containing dissolved metals in concentrations over and above environmental standards, when the pH is close to neutrality.

Main steps

1. Preliminary studies/Characterization

Regroups together actions to determine the presence and extent of contamination and the ensuing risks and impacts, and to assess issues associated with non-environmental fields such as geotechnics;

2. Design of reclamation scenarios

Consists in selecting and presenting restoration scenarios for the mining site;

3. Validation by external experts

The chosen reclamation scenario must be based on the best available reclamation techniques and must be technically and economically achievable;

4. Preparation of a reclamation plan

Presents the concepts of the scenario and the preliminary engineering;

5. Obtaining work authorizations and permits

Obtain permits and authorizations from provincial and federal departments or agencies, municipalities, etc., for each work phase;

6. Preparation of plans and specifications for construction

The final plans and specifications are technical documents describing the work so that it can be carried out by a contractor;

7. Carrying out of reclamation work

Awarding of contract(s) to one or more contractors for execution and monitoring of the work;

8. Post-reclamation monitoring and maintenance

Activities carried out to ensure that the work has achieved its environmental, agronomic and geotechnical goals. Infrastructure maintenance.