By The Associated Press

PORTAGE — An environmental group that sued a steelmaker in December for allegedly violating the Clean Water Act at its northwestern Indiana facility says the company continues to release excess amounts of chemicals into a Lake Michigan tributary.

The Environmental Law & Policy Center said ArcelorMittal has had many self-reported violations for chronic toxicity and discharging excess ammonia into the Burns Waterway. The Indiana Department of Environmental Management has reported a total of 13 violations this summer, The Times reported.

ArcelorMittal Burns Harbor’s chronic toxicity exceeded the permitted limit by 1,052% from May 4 to 8 and by 2,050% from June 1 to 5, according to the agency.

Figures show the steel mill exceeded its weekly average limit of ammonia by 3% one week in June and 19% one week in July.

“The reappearance of ArcelorMittal’s permit violations this summer demonstrates why the Environmental Law & Policy Center brought the lawsuit in the first place,” said Jeff Hammons, a staff attorney for the Environmental Law & Policy Center. “It is vital that the outcome of our litigation results in a solution to the ongoing problems and monetary fines sufficient to deter future violations.”

Shira Cohen, ArcelorMittal spokesperson, said the Burns Harbor facility tracks the amount of ammonia and other chemicals it discharges.

“We continue to work closely with IDEM and US EPA to investigate and understand the recently reported elevated levels so that any appropriate actions can be identified and implemented,” Cohen said.

The Chicago-based group said it is suing the manufacturer because the state was not enforcing federal environmental rules.