The PFOA contamination was found in a small neighborhood just to the southeast of the intersection of U.S. Highway 61 and Jamaica Avenue in Cottage Grove. There are about 15 homes in the neighborhood and they share a border with 3M's Cottage Grove production facility. Groundwater under 3M's facility is contaminated with PFCs including PFOA.
Minnesota Pollution Control Agency Superfund supervisor Doug Wetzstein says he's not convinced the plant is the source of the PFOA contamination.
"We don't know yet if it's coming from the facility," he said. "It's somewhat doubtful because the groundwater flow direction would be in the opposite direction."
The flow direction is south, towards the Mississippi River. The homes are located north of the river and the plant.
Wetzstein says there are other possible PFOA sources besides the plant. One is the Woodbury dump site, which 3M used to dispose of PFC waste. It's just a few miles north of the neighborhood. Or, Wetzstein says there could be other PFC dump sites that haven't been identified yet.
Either way though, he thinks the problem is an isolated situation based on the agency's wells tests in the area.
"We've run almost close to a thousand residential samples and it looks like we've only found it in these six so far," he said.
Scott Boomgaarden suspects his private well will be added to that list soon. The Cottage Grove resident lives in the affected neighborhood and he says so far state officials have tested his well three times. His results are not available yet. But Boomgaarden thinks it's likely that his well is also contaminated with PFOA.
"I don't want this stuff in my water. Even if they say it's not something that's going to cause cancer or something like that. It's still something they've done to pollute our water," Boomgaarden.
Boomgaarden has used a carbon filtration system in his home for years, but he says he's still very worried about the safety of his well water.
A few houses away, his neighbor, Anne Redmond, is taking the news in stride.
"I'm 84 years old, I'm not worried. I've lived this long. I don't think it's going to kill me now," Redmond said.
Redmond does have PFOA in her private well. Health officials told her the level isn't high. But it does exceed the state's advisory limit for the chemical which is set based on a lifetime of exposure. So Redman will begin receiving bottled water immediately.
"I'm not too concerned about it. But I will drink the bottled water. I'm sure my kids would want me to. So I will do that," she said.
The Minnesota Department of Health says it doesn't know yet if the PFOA findings in the neighborhood have any implications for Cottage Grove's municipal wells in the future.
Environmental Health Division Director John Linc Stine says so far, the chemical has not been detected in city wells and he says levels of a related chemical, PFBA, have remained fairly constant.
"What we have been doing is we monitor on a monthly basis the levels of the contaminants in the community wells and we have not seen any significant variability in the levels found of PFBA in the Cottage Grove wells in particular, St. Paul Park same thing, Newport and so forth," Stine said.
Stine says that tells him that the PFOA contamination is coming from somewhere else. State officials have asked 3M to figure out where that source might be located.
The Minnesota Pollution Control Agency says it hopes to have results next week for the rest of the neighborhood's private wells.
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