Lake Elmo city leaders are threatening to sue 3M Co. for pollution that made its way into a city well. But the city's attorney in the case cautions that the city may never proceed.

"We have the authority we need to go forward," said City Attorney Doug Shaftel, "but it's only a suit on the day we file."

Translation: Last week's City Council resolution threatening a suit was a rumble of thunder signaling that Lake Elmo's patience is running thin — and that there may well be litigation if 3M doesn't resolve things.

In response, 3M attorney William Brewer expressed surprise that "Lake Elmo would consider, much less pursue, any claims in connection with this issue."

The dispute between the Washington County suburb and the Maplewood-based company, the biggest in the east metro area, has to do with perfluorochemicals (PFCs). City officials say they had been used since the 1950s at a 3M plant in Cottage Grove, and disposed of in the following decades at a since-closed county landfill in Lake Elmo and a 3M disposal facility in adjoining Oakdale.

In 2002, Lake Elmo drilled a well, which was found four years later to have PFCs. City officials said the source was 3M and that concentrations exceeded state and federal limits. The city couldn't use the well and needed to find other means to deliver water, causing "substantial response costs and [unspecified] monetary damages."

Lake Elmo has tried to negotiate a settlement with 3M, according to last week's council resolution, but without success. So the city is threatening a federal suit.

Speaking for 3M, Brewer said: "We have seen no evidence that this community is currently impacted by the environmental presence of PFCs. 3M voluntarily exited from these chemicals well more than a decade ago and, since that time, has worked closely with state regulators and community stakeholders to remediate PFCs from the environment.

"In any event, there is no evidence that these chemicals present any harm to human health at the levels they are typically found in the environment — and that includes in Lake Elmo. The state of Minnesota has been unable to identify a single person who has suffered an adverse health effect due to environmental exposure to these materials."

Any fault may rest, he said, with state regulators and their "management of the Washington County Landfill. The MPCA [Minnesota Pollution Control Agency] has responsibility to address any releases of PFCs from that facility."

Shaftel declined to elaborate beyond the council resolution, other than to clarify that the PFCs never endangered public health.

"The well in which we found contamination in '06 was never opened, it was never pumped for public consumption," he said Friday. "It was drilled and then capped for potential future development, then tested in its dormancy, and the PFCs were found."

David Peterson • 651-925-5039