CHICAGO (CBS)– There was a second spill into the water in northwest Indiana, this one by U.S Steel.

U.S. Steel told CBS 2 they noticed an “oil sheen” on the water at their Midwest plants, which dumps into Burns Ditch.

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To be on the safe side, the Indiana American Water Company shut down its Ogden Dunes Treatment facility in Portage, Indiana.

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Indiana American Water uses water from two Lake Michigan intakes in northwest Indiana.

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They say the spill hasn’t impacted the water and they’re keeping an eye on things, with constant testing.