The number of clients signed up for a potential class-action lawsuit against Wolverine Worldwide doubled to nearly 80 people since Varnum Law filed a letter of intent to sue the shoemaker on October 13. The lawsuit covers groundwater contaminated with PFAS chemicals linked to Wolverine's old dumpsite in Plainfield Township.

"We've been obviously contacted by many, many more seeking information about what to do," said Aaron Phelps, a partner at Varnum.

Related: Grand Rapids law firm plans to sue Wolverine Worldwide

The letter of intent to sue Wolverine in federal court cited the Resource Conservation and Recovery Act, arguing Wolverine improperly handled its House Street dumpsite -- and other dumpsites state investigators are uncovering -- causing health and environmental damages.

Varnum sent the letter to prompt a more proactive health and environmental response from Wolverine, Phelps said.

"We're waiting now to see what they do in response to our letter," he said. "And if they don't respond as well as we think they should, then we can file the lawsuit."

Wolverine Worldwide has provided some Belmont-area homes with kitchen and external filters and has examined some for whole-house filtration systems. But the company is not doing enough to investigate health issues, Phelps said.

"We've also asked Wolverine many times to participate in, help with, blood testing for residents that wish to have that done," he said. "And they still have not agreed to that."

Varnum said it will not file the lawsuit until it has a better grasp on the scope of contamination. The firm also said Wolverine chose Culligan as its whole-house filtration company and will install 40 per week moving forward. Wolverine Worldwide has not confirmed that information.

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