The spill closed beaches around the Indiana Dunes National Lakeshore, officials said.
The Park Service said Wednesday it closed Cowles Bog Beach based on a recommendation that all beaches within three miles of the spill site be closed as a precaution to protect park visitors. The intake, beaches and riverwalk remain closed today.
The EPA, which is overseeing the response to the spill, said the spilled wastewater eventually entered the waterway about 100 yards from Lake Michigan from a drainage pipe. Any chemical spill so close to Lake Michigan is cause for great concern. It says that's a level higher than would be expected in raw lake water. A chemical spill from a steel plant in Portage, Ind., which resulted in the closure of several beaches at the Indiana Dunes early this week.
The EPA does not have a separate hexavalent chromium standard, but the agency is evaluating health effects data to determine whether a maximum level for hexavalent chromium is needed.
That plant will remain offline until further testing shows there's no threat to its lakeside water source. The supply of water from the Borman Park facility is adequate to meet the needs of the company's customers in Northwest Indiana, he said.
The Environmental Protection Agency says water sampling in Lake Michigan and a tributary shows no significant discharge of a potentially carcinogenic chemical from a U.S. Steel Corp. wastewater spill in northern Indiana.
Chicago's tap water "remains safe to drink", the mayor's office said in a statement Thursday afternoon, but Mayor Rahm Emanuel nonetheless released a statement chastising U.S. Steel for the release of the chemical. But on Tuesday "an expansion joint in the rinse-water pipe failed and resulted in the water being released to a different wastewater treatment plant and ultimately (to) Burns Waterway through an outfall".
Operations will be shut down immediately if elevated levels of chromium are detected, U.S. Steel said. It's also unclear how much of the toxic wastewater spilled.
"The fact that these unsafe chemicals have not reached Chicago's water supply is simply due to good luck, and not good actions by U.S. Steel".
Save the Dunes, an environmental protection group in IN, is also warning people from coming into direct contact with the chemical, which they say is "the same carcinogenic chemical that appeared in the 2000 biographical film, 'Erin Brockovich'".
"Water intake results initially showed hexavalent chromium levels slightly above the detection limit", EPA said. The restart will occur while a water company's nearby intake remains closed and access to parks and beaches in the area remains restricted.
No hexavalent chromium has been detected in the lake following the release of an undetermined amount of toxic wastewater, but monitoring in the area continues, the federal agency said.