After announcing on Sunday the city’s intent to sue U.S. Steel for polluting Lake Michigan, Mayor Rahm Emanuel blasted the company and federal environmental regulators who’ve been “asleep at the switch” under the Trump administration.

“The job of the [Environmental Protection Agency], and let me be clear about this, is to police the polluters, not to protect them,” Emanuel said Sunday outside his City Hall office.

He pointed to two recent spills to highlight his point.

The U.S. Steel plant in Portage, Indiana, released nearly 300 pounds of hexavalent chromium in April because of a pipe failure.

And on Oct. 25, it released 56.7 pounds of chromium after a wastewater treatment system malfunction, nearly double the 30 pounds of the potentially cancer-causing chemical over 24 hours that the plant is permitted to release.

On Monday, city attorneys will begin proceedings required under the Clean Water Act that will allow them to file suit against U.S. Steel. The suit will call for assurances against future leaks and for the EPA to “do it’s job,” Emanuel said.

Unlike the April spill, U.S. Steel didn’t report the latest incident to the National Response Center, a warning system overseen by the U.S. Coast Guard to alert local authorities about oil spills and chemical releases.

A company official wrote to the Indiana Department of Environmental Management on Oct. 31 asking that its submission about the release “be afforded confidential treatment under all applicable statutes.”

“I don’t think it’s an accident that U.S. Steel didn’t report it to the Trump EPA. They know exactly the attitude of the EPA under Donald Trump is that they can get away with it, they’re not going to be policed, they’re complicit in this pollution,” Emanuel said Sunday.

“To the EPA under Donald Trump, this is a wake-up call: Don’t be sending your flimflam stuff and a slap on the wrist to them back here, it’s unacceptable, everyone will be watching you,” Emanuel said.

“The October spill wasn’t serious enough to merit reporting and did not pose any danger to water supply or human health,” U.S. Steel said last week when the latest spill was made public by the University of Chicago’s Abrams Environmental Law Clinic.

A representative of U.S. Steel was not immediately available Sunday.

The Indiana environmental agency is reviewing the case, but excessive chemical releases typically don’t require spill notifications, spokesman Barry Sneed said last week. An EPA spokeswoman agreed that the chromium release “does not appear to exceed” regulations and “would not have to be reported.”