Clean-up is still underway on Lake Michigan after a chemical spill by an Indiana steelmaker. 

ArcelorMittal is claiming responsibility for the spill saying a furnace failure caused cyanide, ammonia, and other chemicals to spill into the water killing more than 3,000 fish. 

The most recent tests show signs of improvement, but people still aren't allowed in the water.

State officials say the failure happened Sunday, August 11th but the company didn't tell the state until Thursday, August 15th.

ArcelorMittal's permit allows the company to release a limited amount of cyanide into the water daily.

The permit also requires cyanide testing twice per month at one outfall and once a week at another, but city leaders say, its not enough.

At one of their outfalls, the limit is 21 pounds; however, their tests showed 188 pounds on August 13th.

The company says it's conducting an internal investigation.