Regulators and Johnson Controls International are sparring over a state requirement that the company assess the extent of contamination in northeastern Wisconsin where industrial chemicals in municipal sludge have been spread on farmland for decades.

The Glendale-based company was to have provided a report to the state Department of Natural Resources on Sept. 3 but did not; and since midsummer, the company and the agency have traded letters over their respective obligations in the matter.

Johnson Controls says it won’t provide documents about how it will address contamination from firefighting foam in the Marinette area until the DNR’s top leaders sit down with the company to discuss the situation.

“We don’t think that letter writing is a productive use of anyone’s time," said John Perkins, a vice president of environment, health and safety issues for Johnson Controls.

"We feel that the most productive use of time and effort — to the satisfaction of the citizens — is to have a dialogue, open and collaborative communications, versus having letters written back and forth.”

The company’s concern: Other parties could also be responsible for contaminating sludge spread for 20 years on thousands of acres. In July, it asked the DNR whether it's been evaluating other sources.

The DNR agrees there are other potential sources of pollution from perfluorinated chemicals, but it's focusing on Johnson Controls because its operations are a known source.

Under state law, it’s identified Johnson Controls as a responsible party for the cleanup, and the agency said this week that the company is required to submit a report on how it will identify contaminated areas. The two sides have been meeting regularly on a staff level, the agency said.

"We didn't say we wouldn't meet with them," said Darsi Foss, administrator of the DNR’s environmental management division, referring to a meeting with agency leaders. "But they need to fulfill what the law requires and that is to submit that work plan."

The dispute follows actions by the DNR in June when it referred Johnson Controls to the state Department of Justice, alleging it waited four years to report the release of hazardous chemicals at its operations in Marinette, resulting in some residents unknowingly drinking water for years that was contaminated.

Earlier this month, Foss told the company in a letter that residents in affected areas are “rightfully” worried about the health effects from potentially toxic sludge.

Marinette residents, for example, have raised concerns about crops grown on fields where sludge has been spread.

"I have seen trailers full of pumpkins for sale," Andi Rich said in an email to the DNR this week and provided to the Milwaukee Journal Sentinel. "... just wanted to make sure people aren't roasting those seeds and feeding them to their kids if they're full of these toxins ..."

Tyco Fire Products, a subsidiary of Johnson Controls, had sprayed firefighting foam with perfluorinated chemicals at a training center in Marinette since 1962. It ended outdoor testing and training sessions there in late 2017.

The compounds are often described generically as PFAS, or “forever” chemicals, because of their difficulty to break down in the environment. They pose potential health hazards to humans, and Johnson Controls is currently providing water to homes with tainted wells.

The PFAS contamination in Marinette is the most widely known in Wisconsin. In August, Johnson Controls said it was setting aside $140 million in its fiscal third quarter on the cleanup.

In addition to sludge, the company is in the early stages of a massive cleanup in areas of Marinette and the Town of Peshtigo after tests showed chemicals in soil, groundwater and surface water stemming from its facilities.

The impact of contaminated sludge arose when it was learned that chemicals from Tyco were flushed down sewers to Marinette’s wastewater treatment plant.

Leftover sludge — some of it found to be tainted with the chemicals — is known to have been spread on more than 3,500 acres of agricultural land in the region between 1997 and 2017.

On July 3, the DNR directed Johnson Controls to expand the PFAS investigation to include sludge in the fields. The DNR also wants the company to assess potential effects to private wells where the sludge was spread.

In addition, the agency said the company should sample water “on a regular schedule" in the Peshtigo and Marinette rivers, both tributaries to Lake Michigan, “until such time that it is determined that PFAS contamination is not an issue in these water bodies …” according to state records.

But Johnson Controls wants the DNR to identify other potential sources of contamination, and in a letter Monday told the DNR that "we know that it is nearly certain that multiple potential sources of PFAS exist in the area ..."

Perkins said three of five sewer lines leading to Marinette's treatment plant were tied to company operations. Two other lines not connected to the company also tested positive for PFAS.

"What we have asked for is to have a sit-down discussion with WDNR to specifically walk through and look at a comprehensive solution because we know there are other sources of PFAS within the city of Marinette," he said.

The company said once it's had a meeting with DNR Secretary Preston Cole, who was appointed by Democratic Gov. Tony Evers and other top officials of the agency, it will provide the report within 30 days.

Said Foss:

"We need some data, some sampling data, that says what is out in those fields and what could have been the sources. Without that, we really don’t have information to look at other potential people.”

In July, the DNR identified ChemDesign Products of Marinette as an additional responsible party in the pollution case. ChemDesign, which was acquired by Milwaukee-based Lubar & Co. in 2012, manufactures chemicals in firefighting foams.

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