The east metro communities that sit above 100 square miles of contaminated groundwater are about to get $850 million from the state's settlement with the 3M Co. that they can devote to clean water — an amount that's eight times what Minnesota's Legacy Amendment provides annually for water projects across the entire state.

"It will bring real and fairly quick relief to the people," Minnesota Attorney General Lori Swanson said at a news conference Wednesday to explain how the settlement will work and how the money can be spent. She was flanked by commissioners from the Pollution Control Agency and the Department of Natural Resources, which were parties to the suit.

The settlement over perfluorinated chemical contamination was reached Tuesday, the day a trial was set to begin, and $20 million will be available immediately, officials said.

A working group will be formed made up of experts, local government officials and citizens to advise the state government on how the money should be spent. That will be done by spring, said PCA Commissioner John Linc Stine.

The settlement is structured to wall it off from the Legislature, Swanson said, a lesson learned from the 1998 agreement with tobacco companies. The Legislature used the state's portion of the $7.1 billion settlement to balance the budget rather than improving the health of citizens, she said.

Officials from the DNR and PCA will act as trustees, and Hennepin County District Court will retain legal authority.

The first priority for the money will be to protect drinking water for municipal systems in Woodbury, Oakdale, Lake Elmo, Cottage Grove, St. Paul Park, Afton and Newport. That also includes some 650 homes with contaminated private wells.

That could include deeper wells, sophisticated treatment plants and under-sink filtration systems for homes.

But it could also include the purchase of land to create natural environments as a way to increase the amount of clean water going into the ground and aquifers.

Priority will be given to water systems where the health risk limits for perfluorinated chemicals, or PFCs, are exceeded. Those community systems are now meeting the health limits by blending water or with temporary treatment systems. Homeowners are getting bottled water or have had home systems installed.

But Stine described those as temporary solutions that can now be replaced by more permanent ones.

The settlement also addresses water supply. Population and economic growth in the area are raising concerns about whether there will be enough water in the future. The money will allow exploration into conservation and even water reuse.

The second priority will be protecting and improving the environment by increasing habitats for birds, fish and other animals now contaminated with PFCs. That could include the complex and expensive process of removing tainted sediment from the bottom of the Mississippi River or creating new habitat in uncontaminated regions.

It could also include new parks and piers in lakes where fish do not carry PFC consumption warnings, as they do in the Mississippi River.

Josephine Marcotty • 612-673-7394