CHICAGO (CBS) — Local environmental activists have said they’re not getting the answers they want from City Hall about an oil spill that occurred in northwest Indiana a year ago this week.

Debra Michaud, of Tar Sands Free Midwest, said a year after a malfunction at the BP Whiting refinery oil caused up to 1,600 gallons of oil to spill into Lake Michigan, she and other activists were demanding Mayor Rahm Emanuel press harder for a full accounting of the incident, and the damage.

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“According to what we can find in the press, we don’t see that he’s done anything. We don’t have any indication that he’s followed through on his demands for accountability by BP. If that exists, it hasn’t been spoken to the public,” she said.

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The mayor’s office said BP responded to Emanuel’s initial demand last May, with a letter outlining the steps it had taken to clean up the spill, in conjunction with the Environmental Protection Agency and the U.S. Coast Guard. A spokeswoman said the mayor made it clear to BP that he expects the company to be vigilant in its work to prevent future spills.

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