The release of the final environmental review of Enbridge Energy's controversial "Line 3" pipeline replacement has been pushed back a week to give the state more time to respond to the voluminous public comments on the project.

The final environmental-impact statement (EIS) was due out Thursday from the Minnesota Department of Commerce. Gov. Mark Dayton on Wednesday directed the department to extend the deadline until Aug. 17, noting that the draft EIS — which was released in May — has received more than 2,860 public comments.

As part of the final EIS, the Commerce Department has to respond to all substantive comments. The draft EIS has been criticized as deficient on several fronts by environmental groups and American Indian bands, who oppose Enbridge's Line 3 plans.

A few years ago, the Calgary, Alta.-based company proposed to replace the aging Line 3, which carries crude oil from Alberta across northern Minnesota to the company's terminal in Superior, Wis. The 337-mile new Line 3 would run parallel to the old Line 3 to Clearbrook, but would then jog south toward Park Rapids through an area known for pristine waters and wild rice lakes.

The pipeline, built in the 1960s, requires extensive maintenance and is only operating at about half of its capacity for safety reasons. The $2.6 billion replacement pipeline would restore the full flow of oil on Line 3.

The draft EIS concluded that Enbridge's preferred route would cause more habitat loss and have more impact on wild rice lakes than any of the four alternative routes being looked at by state regulators.

But impacts on fish and wildlife would vary only slightly between the routes, according to the draft EIS. And environmental and cultural resources would be hurt less by a spill on Enbridge's new Line 3 route than from a spill on two alternative routes that run parallel to the current Line 3.

Friends of the Headwaters said in written comments to state utilities regulators that the draft EIS lacks critical information on the effects of possible oil spills. "Probably the most egregious missing data from the DEIS is that no amounts of oil releases are included at the sites that are examined."

The White Earth Band, in written comments, said the draft EIS does not contain an "explicit explanation of how Enbridge will protect (wild rice) waters, or restore a damaged rice bed. This is totally unacceptable."

The Mille Lacs Band of Ojibwe, in written comments, said the final EIS "should state what percentage of productive wild rice in Minnesota could be affected by the construction and operation" of Line 3 on Enbridge's preferred route.

Enbridge said it was "disappointed" with the delay but understood Dayton's reasons.

After the publication of the final EIS, there is another public comment period, which will last until late September.

The Minnesota Public Utilities Commission is expected to determine whether the EIS is adequate in December. The regulatory process on the Line 3 replacement isn't expected to be completed until April.

Mike Hughlett • 612-673-7003