Although BP’s Whiting refinery is a short distance from the city of Chicago, it is firmly in the state of Indiana and answers to that state and its agencies. But that’s not stopping Chicago Mayor Rahm Emanuel from asking for a full report on this week’s oil spill to be given to the city and the Illinois Environmental Protection Agency.

“I’ll expect a full accounting to the public and the city of Chicago of the damage that was done, how much, what the clean up efforts were, how comprehensive they have been and what actions the company will take to ensure this doesn’t happen again,” Emanuel said Wednesday while announcing a plan to invest $671 million to upgrade the city’s water infrastructure.

A BP spokesman said this week it appears crude oil somehow seeped into the refinery’s water filtration plant that’s adjacent to the lake. Indiana Department of Environmental Management spokesman Dan Goldblatt told WBEZ Wednesday that unconfirmed reports put the amount of spillage at about a dozen barrels of crude oil.

BP has raised its estimate of how much oil spilled into Lake Michigan. The company said Thursday a preliminary estimate shows between 15 and 39 barrels of oil have been recovered from the lake at its Whiting refinery.

A barrel of oil can produce about 42 gallons of gasoline, so potentially 1,638 gallons of oil spilled into Lake Michigan. Earlier estimates had pegged the amount at 10 to 12 barrels of oil.

The spill was detected around 4:30 p.m. Monday. By 9 p.m. a representative with the U.S. EPA said it appeared the leak had been stopped. Cleanup continued Wednesday along the shore of a small private beach between the refinery and its neighbor ArcelorMittal Steel Company.

“BP continues to make progress in responding to an incident Monday at the Whiting Refinery. Crews have recovered the vast majority of oil that had been visible on the surface of a cove-like area of Lake Michigan and on the shoreline between the refinery and a nearby steel mill,” BP announced Wednesday from its US Press Office based in Houston. “They have used vacuum trucks and absorbent boom to contain and clean up the surface oil. Responders also manually collected oil that had reached the shore.”

BP said monitoring continues with the U.S. Coast Guard, U.S. EPA and the Indiana Department of Environmental Management.

“BP and federal agencies are assessing the shoreline to determine what, if any, next steps are required in the response,” a company statement said. “BP continues to work to calculate the amount of oil discharged into the lake. This work involves estimating how much oil was released into the refinery’s cooling water system, water treatment plant and ultimately into the lake.”

According to the U.S. EPA, its Shoreline Cleanup Assessment Team inspected the shoreline today for three hours to assess the presence of oil and to recommend cleanup techniques as required.

“The team saw minimal oiling of the shoreline and recommended a small manual removal crew conduct maintenance along the shoreline,” the U.S. EPA said in a news release. “Weather and wind conditions improved overnight allowing teams to once again secure boom.”

Sources involved in the cleanup say the crude oil that spilled into the lake was a combination of so-called sweet crude (from domestic sources) and crude from Canada’s Tar Sands region, which is considered heavier and dirtier. The tar sands oil is a source of contention among environmentalists.

“A spill like this one, whether big or small, will continue to garner national headlines. And that is the sort of behavior that will keep BP Whiting the refinery Chicagoans love to hate,” Henry Henderson, Midwest program director of the Chicago office for the Natural Resources Defense Council, wrote in a blog post.

So far, no Indiana or Northwest Indiana public official have made statements regarding the spill. BP represents a major source of jobs and property taxes for Northwest Indiana, and the company just recently completed a $4 billion modernization of the more than 100 year old Whiting refinery.

But BP often has been on the receiving end of scathing comments by Illinois officials.

Lately, Mayor Emanuel, Gov. Pat Quinn and U.S. Senator Dick Durbin have taken the company to task for transporting thousands of tons of pet coke, short for petroleum coke, to a site on Chicago’s Southeast side. Residents there have complained about the dust-like substance making them sick when it becomes airborne.

Some city officials want the substance completely banned though so far Emanuel is only pushing an ordinance that would severely restrict the use and storage of pet coke. But with the new oil spill BP is under the microscope again.

“I want to make sure that BP is a good corporate citizen next door in Indiana,” Emanuel said.

And, at least for now, BP is responding.

“We’ve been engaged with the mayor’s office since the onset of this incident and are providing his office with regular updates, “ BP spokesman Scott Dean told WBEZ Wednesday night. “We will also continue to keep the public and relevant authorities informed as we investigate this matter.”

This post was updated on March 28, 2014.