BP refinery spills oil into Lake Michigan

A leak at a BP refinery has spilled an unknown amount of oil into Lake Michigan in Indiana, with the Coast Guard on Wednesday estimating that at least nine to 18 barrels (378 to 756 gallons) of oil were spilled.

The spill occurred Monday afternoon after a malfunction at the facility, which began processing Canadian tar sands oil less than a year ago. The amount of oil spilled is based on an initial visual estimate and may change, a U.S. Coast Guard spokesman said.

An area of about 5,000 square feet of water was coated in an oily sheen and oil slicks could be seen on the shore and rocks, BP said in an initial report to the Environmental Protection Agency (EPA).

"The malfunction occurred at the refinery's largest crude distillation unit, the centerpiece of a nearly $4 billion overhaul that allowed BP to process more heavy Canadian oil from the tar sands region of Alberta," the Chicago Times reported. "The unit ... performs one of the first steps in the refining of crude oil into gasoline and other fuels."

Cleanup efforts continued Wednesday as crews vacuumed up 5,200 gallons of oily water from the area, a U.S. Coast Guard spokesman said.

Strong winds and waves displaced barriers that had been set up to block the oil at the mouth of the cove where the spill occurred. The barriers were later replaced.

The winds blew the oil farther into the cove up onto the shoreline, the Coast guard spokesman said. There is no evidence that oil leaked outside of the containment boom, the EPA said. 

Republican Sen. Mark Kirk and Democratic Sen. Dick Durbin of Illinois said in a joint statement Tuesday that they are "extremely concerned" about future spills, especially in light of BP's recent announcement that it is doubling tar sands processing at the refinery.

“We cannot be too careful when it comes to protecting the health and safety of Lake Michigan which serves as the primary source of drinking water for millions of people in and around Chicago. Protecting our Great Lakes and the economic and environmental impact they have on our state should be a top priority," the statement read.

The fact that it is still unclear how much oil made its way into the lake has angered environmentalists, and has led to calls for increased transparency.

"Changes in our oil sector are not about distant activities and oil rigs," Henry Henderson of the National Resources Defense Council (NRDC) said Wednesday. "They are about immediate impacts people are starting to see in their homes, families and neighborhoods: polluted waters; mounds of solid waste; risky transportation schemes that bring filth, explosions, pollution and destruction to our homes, waters and air in the form of oil trains and leaky pipelines."

Tar sands oil from Canada's Alberta province is some of the dirtiest fuel in use, according to some environmentalists. A recent report by the Council of Canadians cited plans by various energy companies to transport oil and gas under and across the Great Lakes.

"Refining of tar sands crude in American refineries has also exploded; there are now 66 U.S. refineries processing Alberta bitumen, the majority of which are located in states within the Great Lakes Basin," the report said.

Al Jazeera and Reuters