On the morning of April 11, 2017, workers at the U.S. Steel Corp.’s Midwest Plant in Portage noticed water surrounding the plant’s wastewater outfall 004 discharge area in the Burns Waterway was tinted bluish-green instead of its usual grayish-brown hue.

The workers reported the discoloration, setting off a state and federal response to investigate the discharge.

Investigators found that highly acidic chromium trioxide had made its way into a containment trench. The chemical mixed with water and ate through the trench and a wastewater pipeline under the trench, routing the water into a treatment plant that could not handle the acidic wastewater.

U.S. Steel reported that nearly 300 pounds of hexavalent chromium, a cancer-causing version of the chemical created by oxidation during the release, were released into the Burns Waterway.

The spill of the chemical led to Indiana American Water closing a plant to prevent the drawing of water from Lake Michigan and the closure of beaches at the Indiana Dunes National Park and neighboring Ogden Dunes.

A U.S. Environmental Protection Agency investigation days after the spill found the U.S. Steel Midwest Plant had compliance and monitoring issues dating back to 2013 that may have contributed to the spill.

Now, more than four years after the spill, a federal court has approved an agreement between the U.S. Department of Justice and U.S. Steel that would require the company to pay a civil penalty, reimburse federal agencies that responded to the spill and improve wastewater treatment and monitoring systems.

The U.S. District Court for the Northern District of Indiana approved the consent decree after several revisions that incorporated public input, tightening some requirements in the agreement.

“We are pleased the District Court has granted the governments’ motion to enter the revised consent decree, making it an enforceable final judgment of the Court,” said acting U.S. Attorney Tina Nommay for the Northern District of Indiana. “The revised decree requires U.S. Steel to take appropriate measures to protect and restore the waterways, including Lake Michigan, that were harmed by the April 2017 spill, and adopts the robust reporting requirements requested during the public comment period for any future spills.”

U.S. Steel will have to pay a $601,242 civil penalty and reimburse the EPA and National Park Service for response costs the agencies incurred during the April 2017 spill.

The company will also have to pay the NPS more than $240,000 for damages resulting from the beach closures along the Indiana Dunes National Park, as well as $27,512 to the National Oceanic and Atmospheric Administration for natural resource damage assessment costs.

The consent decree will also require U.S. Steel to adhere to plans approved by the EPA and the Indiana Department of Environmental Management for facility wastewater operation and maintenance, preventive maintenance and chromium and wastewater process monitoring.

“Lake Michigan is one of our most prized natural resources and we are committed to protecting it,” said EPA Region 5 Acting Administrator Cheryl Newton. “EPA will continue to make sure facilities comply with the federal requirements that safeguard our communities and our lakes and rivers.”

Since the April 2017 spill, the Midwest Plant has had a troubled discharge record that has cost the multi-billion-dollar corporation relatively little in financial penalties, but has added to its regulatory requirements.

Just six months after the initial spill, the plant continued to exceed the amount of chromium discharge allowed by its federal permit. On Oct. 25 and 26, the plant admitted discharging nearly double its allowed amount of total chromium.

IDEM staff performed a reconnaissance inspection in November 2017 and found operation, self-monitoring and effluent limits compliance violations.

A year later, IDEM officials investigated an anonymous complaint the Midwest Plant was discharging foam and scum into the Burns Waterway. They found “excessive foaming” later identified as oil and grease at outfall 004, the same discharge outfall involved in the April 2017 spill.

IDEM found the facility was discharging oily foam in multiple inspections, and one inspection found sulfuric acid being discharged, a fact U.S. Steel did not disclose to downstream residents. In another incident, the plant found elevated hexavalent chromium concentrations at a wastewater treatment site but released 33,000 gallons of wastewater before operators shut it down.

U.S. Steel was assessed a $950,000 civil penalty, $650,000 of which had to be paid to IDEM. The company was given the option of paying the rest to IDEM or giving a $600,000 tax deductible contribution to the Dunes Learning Center. The company also has to abide by stricter monitoring and reporting requirements.

If the company does not adhere to the consent decree or the agreement with IDEM, it could face more fines and monitoring requirements.