Mercury has been detected in wastewater coming from an industrial barrel refurbishing plant in St. Francis for at least four years — and more than a dozen times levels exceeded legally permitted limits.

Since at least January 2013, records show the Milwaukee Metropolitan Sewerage District has repeatedly issued warning letters to the company that runs the Mid-America Steel Drum plant, asking it to solve its mercury discharge problem.

But the district issued no fines and took no action against the company's permit and the violations continued, a Milwaukee Journal Sentinel investigation has found.

Mercury, a heavy metal, is a closely monitored environmental toxin that in high enough concentrations can attack the nervous system of humans and wildlife.

The levels detected coming from the Mid-America plant are not typically considered a health risk, but experts say they are still a concern because released mercury builds up in the environment. In Milwaukee, it collects in rivers and Lake Michigan sediment, passes into fish and over time presents a risk to people.

"It's a small amount, but it suggests they have a problem in the process that needs to be rectified," said Michael Carvan, a professor at the University of Wisconsin-Milwaukee's School of Freshwater Sciences.

"They have to go after this," he said. "If you let one company get away with it, you'll have others pushing it."

Sewerage district officials finally sought to address the issue further when it summoned the company to an enforcement meeting in March — a month after publication of an investigation by the Journal Sentinel that revealed environmental and workplace violations at barrel refurbishing plants in Milwaukee County and other states.

The three plants, known locally as Mid-America, are operated by Container Life Cycle Management, a joint venture majority owned by Greif Inc., a $3.3 billion packaging giant based in Ohio. The plants refurbish 55-gallon steel drums and large plastic chemical containers, cleaning them for reuse or recycling.

Workers at the plants told the Journal Sentinel chemicals were routinely mixed together, triggering dangerous reactions that resulted in chemical and heat-related burns, injuries from exploding barrels, breathing difficulties and other health problems.

The investigation also found that at the plant on W. Cornell St. in Milwaukee, workers and one of the company's own safety managers said residue from dangerous chemicals went directly down the drain.

“Whatever was left in there is going straight into the sewer," the safety manager said in a conversation that was secretly recorded by a whistleblower. "We have no permits.”

Since the Journal Sentinel investigation, at least five government agencies have launched their own probes into the operations. The state Department of Natural Resources and the U.S. Department of Transportation both recorded violations at the facilities and are looking at other plants nationwide. Other investigations are ongoing.

The sewerage district didn't even know the Cornell St. plant was operating until it read about it in the Journal Sentinel, according to a Feb. 28 letter to the plant's manager. The letter noted that the company had established "a pattern of noncompliance at this facility" with its mercury discharges.

At the meeting with MMSD, company officials proposed a plan to eliminate the mercury discharges. They pledged to clean out pipes, equipment and floors where mercury was detected, install new filters, and improve its "preapproval process" to make sure the company was not taking in steel barrels and plastic totes containing mercury.

The mercury cleanup was done in July, records show. Two tests taken since then indicate the presence of mercury, but both were below the legal limit.

The company applied for a wastewater permit for the Cornell St. plant — the one the district did not even know existed. But it withdrew that application and instead sealed off the sewer drain, promising to make the plant a "zero discharge" facility, records show.

A Greif spokeswoman said the company has been working with the sewerage district to "achieve and maintain compliance with permitted limits."

"The St. Francis facility is currently operating within permitted limits and we intended to maintain that status," spokeswoman Debbie Crow wrote in an email.

For the Cornell facility, the company maintains there will be no water coming from the site into sewers.

"Water associated with the process is now collected in totes and shipped offsite using a licensed disposal company," Crow wrote. "The facility continues to evaluate options to recirculate the water within the facility to further decrease overall water usage at the site."

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Years of violations

The sewerage district recorded mercury discharge violations at the St. Francis plant at least as far back as January 2013, records released to the Journal Sentinel show.

Since then, the plant had 64 water tests showing the presence of mercury; 16 were over the legal limit. The district issued more than a dozen letters to Mid-America between January 2014 and August of this year, asking that the company solve the problem.

In an October 2014 letter, the district said it could take enforcement action including putting Mid-America on a published list of violators; revoking the plant's wastewater discharge permit; and seeking an injunction or a fine of up to $10,000 a day per violation.

The district included Mid-America on the list of a dozen to two dozen polluters published as a legal notice annually in the Journal Sentinel. The company is one of a few that has been on the list since 2015 and will be on the list published early next year based on results in the first half of 2017.

The company has been charged the cost of testing the water at the plant, which comes to about $51,000 to date. Additional testing was triggered by the violations.

But the sewerage district did not fine the company for the mercury violations.

The agency typically opts for a collaborative approach instead of going right to fines, which can take a long time, said Sharon Mertens, the district's director of water quality protections.

"We have had cases in the past where there is an egregious issue and enforcement went very quickly. We were on it in a very short period of time, but this was not that," she said. "This was a sporadic situation in which there didn’t seem to be a clear pattern."

Mertens said that while the company was in violation, she noted several of the violations were only slightly over the permitted levels.

"As a regulator, from my standpoint, it is always preferable to solve the problem and work together collaboratively," Mertens said. "Penalizing and fining is the last resort."

Mertens said it is rare to have an industrial plan operating without the knowledge of the district, as occurred with the company's Cornell St. facility in Milwaukee, but officials are still not sure what was happening at the plant before they inspected it.

Mertens said the district tested pipes leading from the plants, but found no evidence of illegal dumping of chemicals.

Susan Keane, deputy health director at the Natural Resources Defense Council, a national environmental group, said agencies like the sewerage district should aggressively enforce limits on mercury discharge by companies.

And while the levels detected are low, she noted that the sewerage district discharge water is just one possible source of the toxin.

"Mercury getting into the Great Lakes is no small thing," she said. "That is a big concern because it stays around forever."

Raquel Rutledge of the Milwaukee Journal Sentinel staff contributed to this report.

Read the investigation

To read past stories in the Milwaukee Journal Sentinel's Burned investigation, into problems at barrel refurbishing plants around the country, go to jsonline.com/burned.