The Universal Plating property is located at 1900, 1912, 1922 Monroe Street Northeast and 661 19th Avenue Northeast in Minneapolis. The site was referred to the MPCA based on investigations conducted by a voluntary party. A chemical and mechanical plating and finishing facility operated on the property from 1944 through 2009. The site has been in MPCA's Voluntary Investigation and Cleanup Program since April 2014 and once before that.
What's the problem?
In 2012, metals were detected in the site's soil at concentrations that exceed the MPCA’s soil reference values (SRVs) for residential land use. The levels found included:
- Arsenic up to 44.6 mg/kg (SRV of 9 mg/kg)
- Cadmium up to 128 mg/kg (SRV of 25 mg/kg)
- Chromium up to 610 mg/kg (SRV of 87 mg/kg)
- Copper up to 1750 mg/kg (SRV of 100 mg/kg)
- Lead up to 7,350 mg/kg (SRV of 300 mg/kg)
- Nickel up to 515 mg/kg (SRV of 560 mg/kg)
Chlorinated solvents detected in soil included:
- Cis-1,2 dichloroethene up to 44.1 mg/kg (SRV of 8 mg/kg)
- Tetrachloroethene (PCE) up to 10.2 mg/kg (SRV of 72 mg/kg)
- Trichloroethene (TCE) up to 60.8 mg/kg (SRV of 29 mg/kg)
TCE and cis-1,2 dichloroethene concentrations exceed the MPCA’s SRVs for residential land use. Calculated benzo [a]-pyrene (BaP) equivalents were detected in soil up to 5.35 mg/kg and cyanide was detected in soil up to 129 mg/kg, both of which exceed the MPCA’s SRVs for residential land use. Chlorinated solvents detected in groundwater included PCE up to 2.7 µg/l and TCE up to 144 µg/l. The TCE concentration in groundwater is more than 360 times the health risk limit of 0.4 µg/l set by the Minnesota Department of Health for drinking water. Methylene chloride was detected in soil vapors up to 206 ug/m3, and TCE was detected in soil vapors up to 1,650 µg/m3, which exceeds the MPCA’s intrusion screening value (ISV) for residential land use by 275 times.
In November 2015, an investigation indicated that soil vapors migrating off-site and into a nearby residential neighborhood was not a present concern. However, attempts to define the extent and magnitude of the groundwater releases were unsuccessful, and the investigation is not yet completed.
Possible health effects
Metals and chlorinated solvents (like TCE) in soil pose a risk to people who come into contact with them. Chlorinated solvents can move down through the soil and contaminate the groundwater. If the groundwater is contaminated, it can release vapors back into the soil which can intrude into nearby buildings and pose health risks to the people living and working in them. Soil vapor concentrations of TCE on the site are currently well above the residential ISV.