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DuPont and Chemours Co. have agreed to pay $670.7 million to settle 3,550 lawsuits in multidistrict litigation related to the supposed dumping of a toxic chemical, known as C8, into the Ohio River near a former DuPont factory in West Virginia.

The companies announced the settlement in separate press releases Monday morning. According to the statements, DuPont and Chemours will split the cash payment evenly to extinguish all claims pending in an Ohio federal court. Neither company admitted any wrongdoing in statements announcing the accord.

Chemours—though not a named defendant in the MDL—was likely on the hook to pay some of DuPont’s legal costs, thanks to a separation agreement it signed when it was spun off from DuPont in 2014. The Parkersburg, West Virginia, Washington Works plant, formerly under the control of DuPont, is now owned and operated by Chemours.

In a filing with the U.S. Securities and Exchange Commission, DuPont said the parties agreed to the global settlement on Saturday.

The settlement is not subject to court approval, and both sides have agreed to draft a master settlement agreement to “address the timing and logistics of the settlement payment,” DuPont said in the filing. The master agreement, the company said, is expected to include a “walk-away” right that enables DuPont to terminate the settlement if a certain number of plaintiffs opt not to participate.

As a part of the settlement, Chemours would pay up to $25 million per year for the next five years to cover C8 liabilities outside of the settlement, and DuPont would pick up any expenses in excess of $25 million.

After five years, Chemours’ indemnification obligations under the separation agreement will continue unchanged, and DuPont retains no commitment to fund C8-related costs, the company said. DuPont’s settlement payment is not subject to indemnification by Chemours, DuPont said.

Chemours has also agreed not to contest its liability to DuPont for punitive damages, fines, penalties or attorney fees. It did, however, reserve the right to challenge whether a particular C8 claim falls within the scope of indemnification provisions in the separation agreement.

“We are pleased to have reached a mutually satisfactory resolution for all parties that brings this matter to a close,” DuPont said in a prepared statement provided by a spokesman.

Robert A. Bilott, of Taft Stettinius & Hollister in Cincinnati, represents the approximately 3,550 class members who said they had become sick after the chemical contaminated the drinking water around DuPont’s Washington Works plant.

On Monday, he touted the deal as a win for his clients.

“This is a tremendous positive step toward resolving this litigation in a way that provides compensation for our injured clients without the need for additional, lengthy and expensive trials,” Bilott said in an emailed statement. “We look forward to working with DuPont to finalize this settlement and get these injured class members paid as quickly as possible.”

C8, also known as PFOA, was used to make Teflon and has been linked in recent years to a range of diseases, including cancer, pregnancy-induced hypertension and ulcerative colitis.

Federal juries in Ohio have already returned hefty verdicts against DuPont in the few cases that have gone to trial.

In January, Kenneth Vigneron, who suffers from testicular cancer, received $10.5 million in punitive damages, just weeks after a jury found that the Wilmington-based chemical giant had acted with actual malice in discharging C8 into the local water supply. The same jury also awarded Vigneron $2 million in compensatory damages in December.

That payout was the largest of a series of bellwether cases used to test the strength of the cases, which were consolidated in the U.S. District Court for the Southern District of Ohio. One plaintiff last summer received a total of $5.6 million in damages, and another was awarded $1.6 million on her negligence claims.

DuPont has said that approximately 70 percent of the cases allege personal injury claims associated with high cholesterol and thyroid disease, and 10 percent involve claims that C8 in drinking water caused cancer. The company estimates that 30 of the lawsuits involve claims for wrongful death.

In 2001, DuPont reached a settlement with 80,000 residents near the Washington Works plant that resulted in a $70 million payment to class members and a $23 million charge for attorney fees. And a scientific panel determined in 2013 that DuPont must fund up to $235 million in medical monitoring, in addition to administrative costs and legal fees.

The company is also subject to environmental laws and regulations that would require it to undertake investigative, remediation and restoration efforts in the affected area.

DuPont has so far set aside at least $492 million to deal with environmental contingencies, which it said could require payments over the course of 15 to 20 years. But DuPont’s potential liability could increase to more than $1 billion over that amount, the company said last year in an SEC filing.

DuPont is represented in the MDL by a team of Squire Patton Boggs attorneys that included Pierre H. Bergeron, Aaron T. Brogdon and Aneca E. Lasley. Defense counsel also included the firms Kirkland & Ellis, Spilman Thomas & Battle and Hunt & Wilson, according to an online docket-tracking service.