A malfunction at a BP refinery in Whiting, Ind., spilled crude oil into Lake Michigan before it was discovered.
The malfunction was found around 4:30 p.m. on Monday, according to BP spokesman Scott Dean.
The problem caused oil from the Whiting Refinery’s “cooling water outfall” to spill into the cove between the wastewater treatment plant and the steel mill.
It is unclear how much crude oil was spilled. No one was injured.
"The discharge has stopped," Dean said, "and BP and its response team have deployed boom, containing the oil to a cove."
Dean said “a couple of booms” were put in the water and the oil sheen was no longer visible in the water early Tuesday.
He said BP promptly reported the incident to U.S. Environmental Protection Agency, the Indiana Department of Environmental Management and the U.S. Coast Guard.
State and federal environmental officials are at the scene as cleanup is reportedly underway.
Another spill cleanup is underway off the coast of Texas after an oil barge collided with a ship in Galveston Bay Saturday spilling over 150,000 gallons of tar-like oil.
A study from the National Oceanic and Atmospheric Administration published Monday shows the affects of oil on fish in the wake of the 2010 BP oil spill off the Coast of Louisiana, when the Deepwater Horizon oilrig exploded and oil spewed into the Gulf for 87 days.
Researchers tested embryos exposed to the same concentration of oil and found "severely malformed and malfunctioning hearts.”