ST. PAUL, Minn. (AP) — Enbridge Energy's proposal to replace its Line 3 crude oil pipeline across northern Minnesota has taken a step forward.

The Minnesota Public Utilities Commission on Friday approved plans for conducting an environmental review of the $2.6 billion project, which would replace a nearly 60-year-old pipeline doesn't run at its original capacity. The pipeline runs from Alberta, Canada, to Superior, Wisconsin.

The PUC denied a request by environmental and tribal groups to reopen the public comment period and further delay the project.

Enbridge wants to run part of the replacement along the same route it proposed for the Sandpiper pipeline.

But Enbridge recently canceled Sandpiper when it announced it intends to buy a $1.5 billion stake in a pipeline system that includes Dakota Access, which has been the subject of tribal protests in North Dakota.