Lac Windfall Mine Project

Osisko Mining Inc. is proposing the construction, operation and decommissioning of a underground gold mine located on the Eeyou Istchee-James Bay Territory, about 75 km southeast of the Cree village of Waswanipi and 115 km east of Lebel-sur-Quévillon, Quebec. The Lac Windfall Mine Project would have an ore production capacity of approximately 1,900 tonnes per day over a period of up to 10 years. Additional project components would include an ore processing plant, a tailings pond, ore, waste rock and overburden storage areas, two operating ramps and the widening of a bridge.

Latest update

August 29, 2022 – The environmental assessment of the Lac Windfall Mine Project has terminated. The proponent has not provided the Impact Assessment Agency of Canada with the required information or studies within the legislated time limit.


Key documents

Key documents
Document Number Document Title File Date
11 Notice of Termination - August 29, 2022
10 Final Environmental Impact Statement Guidelines PDF (947 KB) September 27, 2017
6 Notice of Commencement of an Environmental Assessment - July 31, 2017
5 Notice of Environmental Assessment Determination - July 31, 2017
3 Summary of a Project Description of a Designated Project PDF (2.2 MB) June 5, 2017


Impact Assessment Agency of Canada
160 Elgin Street, 22nd Floor
Ottawa, Ontario K1A 0H3
Telephone: 613-957-0700 or 1-866-582-1884
Fax: 613-957-0862

  • Location

    • Eeyou Istchee-James Bay Territory (Quebec)
  • Nature of Activity

    • Mines and Minerals
  • Assessment Status

  • Proponent

    Osisko Mining Inc.
  • Authorities

    • Impact Assessment Agency of Canada
  • Assessment Type

    Environmental assessment under CEAA 2012
  • Reference Number


This map is for illustrative purposes. The markers represent the approximate locations based on available data. More than one marker may be identified for a given assessment.

Nearby assessments

...within 200 kilometres
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