MINNEAPOLIS (AP) - The state of Minnesota is suing 3M Co. over its disposal of chemicals previously used to make Scotchgard and other products.

The lawsuit filed Thursday in Hennepin County alleges 3M damaged the state's natural resources, as well as ground and surface water, by disposing of perfluorochemicals, or PFCs.

PFCs were made by Maplewood-based 3M starting in the 1940s, and legally disposed of them in landfills until the 1970s. 3M stopped making PFCs in 2002.

In 2004, traces of the chemicals were found in groundwater from Lake Elmo to Hastings. The state's lawsuit seeks unspecified damages.

Phone messages left with 3M were not immediately returned.

In May, the state and 3M entered a written agreement to withhold a lawsuit while trying to negotiate an out-of-court settlement. That agreement expired Friday and no settlement has been reached.

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