MINNEAPOLIS - Residents of one Minneapolis neighborhood are being warned of potential dangerous vapors that could be leaking from the soil into their homes.
On Wednesday the Minnesota Department of Health (MDH) and Minnesota Pollution Control Agency (MPCA) sent letters to owners, occupants and renters of homes in the Como neighborhood of southeast Minneapolis.
The letter was to alert them of an ongoing investigation of potentially harmful vapors that may be intruding into homes and buildings.
The soil vapor in question is trichloroethylene, commonly known as TCE. It was used as an industrial solvent at a former General Mills research facility at 2010 E. Hennepin Ave in Minneapolis in the 1940s until the early 1960s.
During that time waste TCE was disposed of in a pit on the property. The contaminated site has been known for more than 30 years. General Mills, under the oversight of the MPCA, pumped and treated groundwater at the site to remove the TCE for 25 years.
Extensive groundwater testing over many years demonstrated that TCE concentrations in the groundwater significantly declined and that the groundwater plume has stabilized. With approval from the MPCA treatment systems were shut down in September 2010.
If TCE levels in the soil beneath any building or home are above the safe level set by MPCA and MDH, General Mills has agreed to install vapor ventilation systems, which work like radon mitigation systems. Such systems are a proven solution for both radon and vapor intrusion problems.
Residents are being alerted to potential health concerns, but the letter stressed that more investigation and testing need to take place in their homes and buildings to evaluate actual risk and determine a suitable response. They were also given contact information for sources at MDH who can talk to them about health risks, and contacts at the MPCA for details on the history of the pollution causing the vapor release.
Two informational open house-community meetings have been scheduled for residents in the area of concern in southeast Minneapolis. Both are planned for Tuesday, Nov. 12, at Van Cleve Recreation Center at 901 15th Ave. SE in Minneapolis. The first runs from 12:30-3 p.m. and the second from 5-7:30 p.m.
Agency representatives will be available to answer questions, followed by presentations at 1:30 and 6 p.m. Additional community informational meetings are also being planned.