The National Wildlife Federation maintains it's time to replace the lines. The group posted a short video taken by divers that appears to show broken supports and sections suspended above the bottom or covered with debris. Critics also complain the company won't release enough data from its inspections of the pipelines and note that above-ground sections of Line 5 have ruptured in numerous spots on land, spilling hundreds of thousands of gallons.
But Guthrie said the underwater section is sound.
"It's been operating there for decades and operating safely," she said.
The U.S. Coast Guard has conducted spill-response exercises in the straits the past three years. Some have taken place in winter to test technology for tracing oil beneath ice, said Steve Keck, a contingency specialist based in Sault Ste. Marie.
Dean Reid, planning commission chairman in Mackinac County who organized the community meeting, said locals needed more information about the pipelines, which many didn't know existed until recently.
"We tend to take for granted what's here," Reid said, "and sometimes don't know what's here."
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