The Alberta Energy Regulator is reconsidering approval of a plan allowing Suncor Energy Inc. to extend its Fort Hills oil-sands mine into nearby wetlands after pressure from an environmental group.

The AER in September approved Suncor’s plan for protecting certain portions of the McClelland Lake Wetlands Complex, a necessary step for allowing mining to expand in the area. The agency said in an email that it’s now reconsidering that approval. 

The Alberta Wilderness Association had asked the regulator to revoke the permission after finding deficiencies in Suncor’s plan that pose “a serious risk” to the wetlands. Suncor didn’t immediately reply to an emailed request for comment.

Located in northern Alberta, Fort Hills is Canada’s newest oil-sands mine. The site began operation about five years ago and produced about 164,000 barrels a day last year, AER data show.  

The Alberta Energy Regulator is facing increased federal oversight and a third-party review of its response to a tailings-pond leak at Imperial Oil Ltd.’s Kearl oil-sands mine that was criticized by local indigenous communities.