Revised Notice of Completion for the Long Lake Gold Mine Rehabilitation

During its operations between 1909 and 1939, the Long Lake Gold Mine discharged approximately 200,000 tonnes of waste created from the mining process, known as mine tailings, into the environment. These tailings contained naturally occurring arsenic that negatively affected the quality of drinking water in Long Lake.

A Notice of Completion for this rehabilitation project was originally issued on August 25, 2017, but the Ministry voluntarily withdrew the notice to address negative impacts of the project identified during the comment period, such as the impact of haul trucks on residents. We have revised the project to mitigate these concerns.

The rehabilitation project will involve the relocation and containment of mine tailings in a new impoundment structure that would be constructed on an existing tailings area. The impoundment will be capped with a cover designed to prevent surface water from coming in contact with the tailings. Areas where tailings have been removed will be graded and vegetated. Natural drainage channels, creek beds and a wetland will be restored to return the site to its natural state as much as possible. The mine tailings that are completely submerged within Long Lake are chemically stable and do not affect water quality. Only the tailings that are submerged in less than two meters of Long Lake will be relocated to the impoundment.

Most of the aggregate material required to backfill excavated areas, build the impoundment structure and prevent erosion will come from sources that will significantly reduce the amount of hauling on residential roads. Haul trucks will be subject to provincial regulations and municipal by-laws that control dust and noise emissions. Other restrictions will be applied to minimize disturbance to residents where needed. 

Access to the project site includes the use of roads along the south side of Long Lake and of approximately two kilometers of trail by, and limited to, ATVs and off-road vehicles . One of these roads (i.e. Lakes End Road) and the trail will be widened to let large trucks and machinery reach the site for the duration of the project. Upon completion of the work, the upgraded trail will be returned to a single-lane trail to allow long-term access for mine site inspection, care and maintenance. Sections of Lakes End Road and the trail are located within the Eden Township Forest Conservation Reserve. Impacts to the conservation reserve were addressed by the Ministry’s Class Environmental Assessment process, which included consultation with the Ministry of Natural Resources and Forestry to identify and mitigate impacts to values within the protected area.