A contractor working for the Minnesota Pollution Control Agency (MPCA) found that concentrations of a known pollutant (trichloroethylene, or TCE) at the former Superior Plating site were low, and should not cause any future health impacts.
However, a previously undiscovered high concentration of Freon was identified near the intersection of SE Bank Street and SE Ortman Street during testing performed by Bay West, an industrial cleanup and disposal company, on Dec. 26 and 27.
“I’m not really concerned about [the Freon concentration],” said Gerald Stahnke, the Superior Plating project manager for the MPCA. “It’s above the current standard, but the current standard is a very conservative number established in the past and not supported by more recent data.”
Freon is a chemical commonly used in refrigeration or as a coolant. According to the MPCA, the pollution likely originated from an automobile repair shop or business associated with refrigeration, but to the MPCA’s knowledge no businesses like that have operated in the area.
“There’s no readily apparent source for it, which is why we think it needs further assessment,” said Stahnke.
The MPCA received more than 30 comments from individuals regarding its plan to demolish the building at the contaminated Superior Plating site, excavate down to the bedrock and haul everything away to an industrial landfill.
Stahnke said he is in the process of responding to all of the comments and after that he hopes to gain approval from the state sometime this winter. Meanwhile, the MPCA is looking into the cost of monitoring and posting daily levels of airborne contaminants during the demolition and hauling, which was requested by several nearby residents.