The Minnesota Pollution Control Agency sent letters to residents of the Como neighborhood in southeast Minneapolis on Wednesday, Nov. 6 to alert them of an ongoing investigation of potentially harmful vapors.
The vapors in question are trichloroethylene (TCE), an industrial solvent used at the former General Mills research facility at 2010 E. Hennepin Avenue from the 1940s to early 1960s.
CLEANING UP CONTAMINATION
TCE waste was dumped into a pit at the research site, which MPCA has been aware of for more than 30 years. Under the agency's oversight, General Mills pumped and treated groundwater at the contaminated site for 25 years.
Groundwater testing found TCE concentrations significantly declined, to the point that the MPCA approved the shutdown of the treatment systems in September 2010. Drinking water in the area was never a health issue since the neighborhood is connected to city water.
TCE VAPORS FOUND
Soil vapor testing was required as the next step in the process. In October 2013, data showing TCE in soil gas samples triggered an alert to residents from the MPCA and health department.
Tuesday, Nov. 12 Van Cleve Recreation Center 901 15th Ave. SE, Minneapolis 12:30-3 p.m. and 5:00-7:30 p.m.
At these meetings, residents and property owners will be informed of the testing locations and procedure, as well as the potential health risks of TCE. Environmental testing at the properties will be performed in the method approved by the MPCA. Testing will begin as soon as testing and mitigation plans are approved and access agreements are signed by property owners.
WHAT IS GENERAL MILLS DOING?
If TCE levels in the soil beneath any property are above the safe level set by the MPCA and Minnesota Department of Health, General Mills has agreed to install vapor ventilation systems, which work like radon mitigation systems.
There is no cost to residents or property owners for testing or mitigation. Vapor intrusion mitigation systems will be offered and installed at no cost in affected homes.