MACKINAW CITY, Mich. (WWJ/AP) – Pipeline company Enbridge says an oil pipeline beneath the Straits of Mackinac in northern Michigan has passed federally required pressure tests.

The test took place Saturday on one pipeline that’s part of Line 5.

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Enbridge pumped the line’s west segment with water and kept pressure high for 8 hours. Enbridge officials told reporters in a conference call Monday the line is fit for service and no leaks were found.

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A second pipeline, called the east segment, will be tested soon.

The pipelines were built in 1953.

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A nearly 5-mile-long section, divided into two lines, runs along the bottom of the straits area where Lakes Huron and Michigan converge.

In July, Enbridge Energy Partners were ordered to pay a $61 million penalty for the costliest inland oil spill in U.S. history.

A nearly 40-mile stretch of the Kalamazoo River was polluted as shoreline residents fled their homes — after an estimated 843,000 gallons of crude oil ruptured from a pipeline in 2010.

 

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