The Biden administration will scrutinize the environmental effects of a portion of a crude oil pipeline in Michigan, wading into a long-waged battle by environmentalists and Gov. Gretchen Whitmer to shut down the pipeline.

The Army Corps of Engineers announced Wednesday it will conduct an environmental impact statement for operator Enbridge Energy’s proposal to construct a tunnel and new pipeline to replace a portion of the current pipeline that runs under the Straits of Mackinac connecting Lake Michigan and Lake Superior.