ANN ARBOR (AP) – A newly released study says hundreds of miles of Lake Michigan and Lake Huron shoreline are at risk of contamination if oil pipelines in the Straits of Mackinac rupture.

The report by the University of Michigan Water Center is based on 840 computer simulations of possible spills from twin lines that run across the floor of the straits linking Michigan’s two peninsulas.

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The pipelines are owned by the Canadian company Enbridge, which says they’ve never leaked and remain in good shape. Environmentalists are pushing to have them removed. Laid in 1953, the pipelines carry up to 20 million gallons of petroleum products every day.

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Hydrodynamics expert David Schwab directed the study released Thursday. He says when all simulated spills are plotted on a map, 720 miles of shoreline in the U.S. and Canada are considered potentially vulnerable. High-risk areas include Mackinac Island and shores near Mackinaw City.

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