Echemi and two related companies said they would pay nearly $1.2 billion on Friday to settle liability claims filed by public water systems that serve the vast majority of the U.S. population, just days after South Carolina began a bellwether trial on PFAS contamination.

PFAS manufacturer 3M is also reportedly considering a settlement to avoid charges that the company knowingly contaminated drinking water supplies across the United States.

The trial, set to begin Monday, is expected to reveal long-held secret documents about what chemical giant 3M knew about the dangers of its perfluoroalkyl and poly-fluoroalkyl substances (PFAS). 3M previously announced it would exit PFAS production by 2025.

Echemi and related companies recently parted ways with the case as they negotiated a settlement in which Echemi would pay about $400 million; Chemours, a subsidiary of Echemi, will pay $592 million; Another Echemi-related company, Corteva, will pay about $193 million.

The companies said the settlement does not cover personal injury claims stemming from alleged exposure to PFAS, as well as claims by state attorneys general regarding PFAS contamination of natural resources.

Bloomberg reported on Friday that 3M was negotiating a $10 billion settlement to settle claims and avoid a trial on Monday.

When asked about a possible settlement, 3M said in a statement: "We do not comment on rumors and speculation."

3M said earlier in a court filing that it was not liable and "never owned, operated, or otherwise controlled the facilities, disposal sites, and other purported sources of PFAS or related compounds." The company said in the filing that the company lacked "necessary controls over products after the point of sale."

The company said in a statement that it is working to stop using PFAS in its portfolio by the end of 2025, even though "PFAS are safely produced and used in many modern products."