For the first time since Minnesota reached its historic $850 million settlement with 3M Co. over the toxic "forever chemicals" polluting ground­water in the east metro, the state has put dollar estimates on the potential fixes being developed.

The $700 million available to spend on cleaning drinking water and restoring damaged natural resources does not go far given the price tags for water treatment plants and home filtering systems, according to the latest draft of treatment scenarios. The scenarios also show the costs of operating and maintaining treatments for 20 years. Including inflation, the options range in cost from $250 million to $1.2 billion.

"Some folks may be a little surprised at the size of some of the numbers," said Kirk Koudelka, assistant commissioner of the Minnesota Pollution Control Agency (MPCA). "One of the troubling things about PFAS is there's nothing in nature that will remove it. It got its name 'forever chemicals' for a good reason."

The big-dollar menu of more than a dozen options is the result of a year-and-a-half of brainstorming, research and diagraming to determine how to spend the settlement money. It's a process other states are watching as they grapple with the massive water contamination from per- and polyfluoroalkyl substances, a family of compounds collectively called PFAS.

The chemicals, famed for their water- and heat-resistant properties, have been widely used by industry — most famously in Teflon — and are in everything from food packaging to mascara. Health officials say PFAS can be found at low levels in the blood of virtually everyone in the United States, and in people and animals across the globe.

The earlier PFAS compounds have been linked to cancer, high cholesterol, immune deficiencies, liver problems and reproductive issues. The crisis has sparked multiple class-action lawsuits and the Hollywood movie "Dark Waters" about DuPont.

Minnesota is further down the road in addressing the pollution than most regions because it's home to 3M, which manufactured the original PFAS chemicals for decades at its plant in Cottage Grove even though the company knew the chemicals were toxic. Then-state Attorney General Lori Swanson originally sought $5 billion from 3M when she sued for environmental damages.

The various drinking water treatment options are being presented at a series of public meetings, including meetings Thursday in Cottage Grove and March 4 in Woodbury. More information is on the MPCA website at 3msettlement.state.mn.us.

The scenarios were developed by three work groups created by the MPCA and Department of Natural Resources, which together manage the 3M settlement fund.

The fact that costs for the different treatment plans only extend 20 years concerned several residents at Wednesday's meeting in Lake Elmo. They said they want to know if they'll be on the hook after that for maintaining expensive home-filtration systems and new water infrastructure.

Lake Elmo resident Jim Blackford said he thinks the state should pick up the ongoing costs after that time frame. Blackford, who has relied on bottled water for years since his private well is contaminated, said he thinks more should be done to incinerate and destroy the PFAS so the problem isn't pushed elsewhere. "The costs go on and on," he said.

Treating drinking water running from taps has taken top priority in the planning. Tackling the plume of contaminated groundwater running beneath the 14 affected communities is a secondary goal. Given the cost of treating drinking water, it's possible there will be no money to tackle the underlying problem or restore water resource for wildlife, Koudelka said in an interview.

At the meeting, Koudelka emphasized that even after settlement funds are gone, 3M must still continue to pay the cost to treat public or private wells that were issued a health advisory by the Minnesota Department of Health, or that it deems a Health Index of one or above for PFAS.

After gathering more public input, the list will be whittled to recommendations — labeled good, better and best — that will be posted this spring for a formal 30-day public comment period. Final recommendations will come in late spring or summer.

The affected area includes Afton, Cottage Grove, Lake Elmo, Lakeland, Lakeland Shores, Maplewood, Newport, Oakdale, St. Paul Park, Woodbury, Denmark, Grey Cloud Island, West Lakeland and the Prairie Island Indian Community.

Under one scenario, filters with ion-exchange resin would be used to remove PFAS from more than 1,000 municipal and private wells in all but two of the communities, costing an estimated $725 million to install and to maintain for 20 years. That's 104% of the settlement funds. Cottage Grove is running a pilot test on the ion-exchange filters at a temporary treatment facility. The Minnesota Department of Health needs to approve the technology before it can be rolled out for PFAS treatment. Currently, filters with granular activated carbon are used to remove PFAS.

Another option is to build two water treatment plants on the Mississippi River and treat more than 2,000 private wells, which would cost an estimated $967 million with 20-year maintenance and inflation.

Cheaper options are more targeted about which wells get treated.

Jennifer Bjorhus • 612-673-4683