Line 6B of the Lakehead pipeline system, one of the longest in the world, ruptured in July near Marshall, Mich., spilling around 20,000 barrels of oil into Talmadge Creek and the Kalamazoo River.
The company in late September received approval from U.S. regulators to restart the pipeline provided Enbridge addressed concerns along Line 6B.
Enbridge had until the end of September to cleanup submerged oil and sediment near the site of the Line 6B rupture.
Rebecca Humphries, the environment director at the Michigan Department of Natural Resources, ordered Enbridge to develop an assessment and containment plan to make sure the areas is restored.
"This order provides a framework for the continuing cleanup and restoration of Talmadge Creek and the Kalamazoo River affected by the July oil spill," she said in a statement. "We look forward to working cooperatively with Enbridge and other responding agencies on the long-term remediation of this spill."
A 12-inch dent was found on a section of the same pipeline running under the St. Clair River.
The U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration said in a restart plan for Line 6B that Enbridge needed to replace the damaged St. Clair leg within a year.