Feb. 3, 2007: Water probe focuses on Woodbury site

3M has 30 days to respond to the state's request for more information on how a chemical was disposed of at a former dump.

By Tom Meersman, Star Tribune

Last update: March 30, 2007 - 12:53 PM

The Minnesota Pollution Control Agency has focused its suspicion on an old 3M dump site in Woodbury as the source of a chemical that has found its way into drinking water in the east metro.

On Thursday, the agency asked Maplewood-based 3M Co. to provide information about the Woodbury disposal, near the city's border with Cottage Grove. The company used it to bury certain wastes from its Cottage Grove plant between 1960 and 1965.

Two weeks ago, health officials discovered traces of a 3M chemical called PFBA in city drinking water supplies of Cottage Grove, Woodbury, St. Paul Park, Newport, South St. Paul and Hastings. Health experts told residents that there were no immediate health concerns about drinking the water, but added that not much is known about long-term effects of exposure to the chemical. They said citizens who were concerned could use bottled water or install granular activated carbon water filters.

Michael Kanner, director of the state Superfund program for the MPCA, said that the agency is trying to determine whether the chemical that has leached into groundwater beneath the 3M Woodbury disposal has been spreading beyond the site, and if so, what to do about it.

"We think the likely suspect is the Woodbury disposal facility, but we've got to prove that out," he said.

In a Feb. 1 letter, the agency asked 3M to develop plans to install monitoring "sentinel" wells between the landfill and nearby homes. This action would help determine the direction and extent of contaminated groundwater. .

30 days response time

The agency also asked 3M to check for leaks in an underground pipe that moves groundwater from the disposal to the 3M manufacturing plant in Cottage Grove. And the MPCA wants 3M to reassess the feasibility of excavating some of the wastes that remain in the northeast portion of the disposal site.

The agency requested that 3M provide a plan for those actions within 30 days.

3M spokesman Bill Nelson said the company received the letter and needs to review its contents. "We will provide the agency with a meaningful reply within the short time specified," he said.

Kanner said that 3M installed pump-out wells at the disposal in the 1970s that are designed to remove contaminated groundwater and prevent it from moving to places where homes or cities draw their water. The agency also wants the company to evaluate how well that pump-out system is working, he said, and whether it needs to be improved.

Public meetings scheduled

Related 3M compounds discovered in groundwater in other communities during the past couple of years have led to a new filtering system for two of Oakdale's city wells and closure of more than 200 private wells in Lake Elmo because those homes were hooked up to city water.

In a related development, state health officials on Friday announced six evening public meetings in the affected communities during the next three weeks. The meetings are designed to provide information about the well testing, explain future actions, and answer questions about health risks, water-filtration systems and other concerns. .

Tom Meersman - 612 673-7388