The Luxembourg-based company that admitted to inadvertently releasing excess levels of cyanide and ammonia into the Little Calumet River in August has denied manipulating test data it submitted to Indiana’s environmental agency.

In a recently released inspection report for ArcelorMittal’s Burns Harbor facility near Gary, the Indiana Department of Environmental Management found several violations during three inspections in November.

One of the violations was ArcelorMittal’s possibly illegal practice of reanalyzing and replacing water discharge samples when the initial sample analysis found levels of a chemical or substance in discharge water beyond what is allowed by state and federal permits.

The company stands by its testing practices.

“ArcelorMittal Burns Harbor does not manipulate data,” the company said in a written statement. “We use certified, independent laboratories to analyze samples and we report the data, including any corrected data from the labs to the regulator agencies consistent with industry and laboratory standards. ArcelorMittal has a track record of providing accurate sampling data to the agencies.”

In August 2019, IDEM began investigating a chemical release after receiving complaints of dead and distressed fish in the East Arm of the Little Calumet River. ArcelorMittal contacted IDEM days after the spill and notified the agency that it had violated its daily maximum limit for total cyanide.

The company said the release of elevated levels of ammonia and cyanide was due to a failure in the blast furnace water recirculation system.

ArcelorMittal Burns Harbor was instructed by IDEM to conduct daily 24-hour composite sampling of the water discharged by Outfall 002, where water from the facility’s coke plant, sinter plant, blast furnaces and other essential areas are discharged.

The company was required to test for unauthorized discharges of ammonia, nitrogen, cyanide and several other chemicals and substances.

The company collected water samples and sent them to independent laboratories for testing.

According to IDEM, sampling deficiencies were found in data submitted by the company in the months after August’s chemical release.

“ArcelorMittal Burns Harbor has established a practice of reanalyzing samples in cases in which initial sample analysis, which passes all quality assurance/quality control checks, indicates a permit effluent limit exceedance, and using the results of the re-analysis to re-calculate or replace results, including those already reported to IDEM,” the report stated.

In short, IDEM said ArcelorMittal Burns Harbor would retest samples that showed violations until it got acceptable results, then used the samples to recalculate effluent averages or even replace unfavorable results.

Reanalyzing a sample is a violation of the Clean Water Act’s National Pollutant Discharge Elimination System, which regulates the amount of pollutants that steel mills and other “point sources” can discharge into U.S. waters.

NPDES allows point sources to collect samples for testing over the course of the day and average the results. This gives point sources leeway to fall under the daily maximum effluent limits for pollutants regulated in the facility’s permit.

IDEM said NDPES rules do not allow a permittee to reanalyze valid analytical results and use that result in place of the initial result.

The agency also said ArcelorMittal’s sampling data puts into question the validity of the company’s self-reported data.

“The practice undermines the integrity of compliant results that are reported based upon one analysis of a given sample,” the report stated. “If ArcelorMittal Burns Harbor maintains that it cannot credibly report noncompliant results based upon one analysis of a given sample (that passes all quality assurance/quality control checks), then IDEM cannot feel confident in compliant results reported by ArcelorMittal Burns Harbor that are based on one analysis of a given sample (that passes all quality assurance/quality control checks). ArcelorMittal’s self-monitoring program is either capable of generating valid results based upon one analysis of a given sample or it is not.”

On Jan. 2, IDEM asked Microbac, one of the companies used by ArcelorMittal to test water samples, to provide more details about the lab data and calculations used to provide analytical results and full details about samples deemed “false positives,” including how the deduction was made.

The report was forwarded to IDEM’s Office of Water Quality enforcement section.

In October, the Indiana Environmental Reporter found that the company submitted noncompliance reports days or weeks after the violations first occurred. In some instances, the company initially reported effluence violations that were slightly above permitted limits, only to revise the submitted report weeks later with a much higher monitored value.

The Chicago-based Environmental Law & Policy Center and Indiana’s Hoosier Environmental Council filed a lawsuit against ArcelorMittal Burns Harbor, LLC and its parent company ArcelorMittal USA, LLC alleging Clean Water Act violations.

The groups say the companies repeatedly violated federal permit effluent limits and narrative water quality standards, then repeatedly violated reporting requirements.

The groups say they can prove ArcelorMittal exceedances as far back as 2015 and are seeking a permanent injunction to stop the company from discharging pollutants into the Little Calumet River and Lake Michigan and to come fully in compliance with the requirements of the Clean Water Act.

The groups want the court to order ArcelorMittal to pay for the cost of litigation and to impose civil penalties for each violation until the company achieves full compliance or until the lawsuit is resolved.

“In the face of this repeated, illegal damage to Lake Michigan, we can no longer just stand by and wait for the state and federal government to act,” said Hoosier Environmental Council Health and Water Policy Director Indra Frank when the lawsuit was announced. “The damage has to stop for the sake of everyone who gets their drinking water from the Lake; everyone who swims, fishes, or boats in the Lake; and the wildlife that make their home in the Lake.”