British Petroleum confirmed today that a malfunctioning processing unit caused oil to leak from the Whiting refinery in Indiana into Lake Michigan last night, potentially affecting the drinking water of 7 million Chicagoans

CBS reports that, according to a source, between 10 and 12 barrels leaked into the lake, up to 540 gallons altogether. According to BP spokesman Scott Dean, "a disruption in the refining process resulted in a crude oil discharge from the BP Whiting Refinery's cooling water outfall into Lake Michigan at approximately 4:30 p.m. Monday." A spokesman for the Indiana Department of Environmental Management told the Chicago Tribune that the flow was stemmed by 1 a.m. on Tuesday. CBS reports that officials are now cleaning up the mess: 

BP said the oil was contained to a cove located between the refinery’s waste water treatment plant, and a steel mill. Vacuum trucks were on hand to assist in the cleanup. Crews also were scooping up oil with their hands, as the cold water in the lake had turned the oil into a hard waxy substance.

BP said that the unit has resumed operations, and explained how it had worked to stop the leak. Again, the Chicago Tribune reports

BP laid booms on the water in an attempt to keep the oil from spreading beyond a cove between the refinery’s wastewater treatment plant and an Arcelor Mittal steel mill. Winds were pushing the oil toward the shore and frigid temperatures caused some of it to harden into a waxy consistency that made it easier to collect, said Scott Dean, a BP spokesman.

It will probably take a few days to figure out how the spill will affect the lake, which we're sure will make everyone in the Chicago area who wants to drink water over the next couple of days feel great.