Potentially harmful vapor levels found under Mpls homes

Initial results show almost two-thirds of homes in the Como neighborhood of Minneapolis tested so far have shown the presence of unsafe soil vapors that exceed state limits.

The testing follows the state's discovery in September of trichloroethylene soil vapors at public sites across the neighborhood. The chemical, also called TCE, was used as an industrial degreaser or cleaner at General Mills' facility in the neighborhood from the 1940s to the 1960s.

General Mills is paying to test for the presence of TCE soil vapors and the installation of ventilation systems in any houses where the vapors are found at levels above state guidelines.

The company released test results on Friday afternoon. They've received results for 69 homes so far. At least 42 of those homes were found to be in need of vapor ventilation systems and another 13 homes will be retested because their levels were slightly higher but didn't exceed state limits.

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Officials want to test 200 homes in the area. Slightly more than half of the homeowners have so far agreed to allow the tests on their property.

General Mills spokesman Tom Forsythe said the company is pleased with the progress so far, but that homeowners have had mixed reactions.

"People appreciate how we're conducting ourselves but they would rather this not have happened, and we would share that view," Forsythe said. "These were past practices from long ago, and we're trying to address that."

Forsythe said the company has the capacity to test 50 houses for the soil vapors and install 50 ventilation systems each week. He urged homeowners in the area to sign the agreement to allow testing under the basements and slabs of their homes.

"Please allow us to test, please allow us to address this issue for you if we can," Forsythe said. "The vapor ventilation system is a proven solution to the issue, so the faster we can move the better."

Two lawsuits seeking class action status were filed this week on behalf of homeowners in the area. The lawsuits allege that residents have suffered property damage due to the TCE contamination. Forsythe declined to comment on the lawsuits.

Contaminants were originally found in water on the site in 1981. A water treatment system was active between 1985 and 2010. General Mills sold the site in 1977.