Workers hired by the state began an emergency cleanup Wednesday of chromium-contaminated water outside Superior Plating, only a week or two before the last production line at the northeast Minneapolis factory is expected to shut down.
It wasn't the first cleanup crew to visit the heavily polluted property, and it won't be the last, as the impending closure will enable a more thorough investigation and cleanup of the contamination left behind by the business.
On Tuesday afternoon, someone who lives nearby spotted a yellow substance next to railroad tracks behind the 92-year-old plant at 315 1st Av. NE. The discovery caused city workers to block off streets and halt the Northstar Line, forcing Metro Transit to put hundreds of train passengers on buses instead.
The chromium has been in the contaminated soil underneath the building for decades and was picked up by groundwater that flows under the building, said Superior Plating President Michael McMonagle. A remediation system is supposed to collect all the groundwater and pump it into a treatment system in the plant.
McMonagle said he thinks the groundwater was thawed by the unusually warm temperatures and either the treatment system was overwhelmed or the polluted groundwater somehow bypassed it. Then the tainted water froze again.
"The problems we have here were created a long time ago ... before people had a sense of protecting the environment," he said.
Because the company filed for Chapter 11 bankruptcy in November, it can't pay for the emergency cleanup.
"We've showed that every time we had an issue, we've taken care of it," McMonagle said. "But I just can't do that today. We don't have the authority."
Instead, the money for the emergency cleanup will come from state funds reserved for sites that, like Superior Plating, have been identified by the Superfund program as hazardous.
A Minnesota Pollution Control Agency report on the site says that "the seepage ... is a concern as it could come in contact with people or animals. The relatively high contaminant concentration in the liquid does classify it as hazardous."
The Superior Plating property has been listed as a Superfund site since 1985. According to the MPCA, the soil and groundwater at the site are contaminated with heavy metals and solvents.
The MPCA says the underground contamination at Superior Plating doesn't pose an immediate health hazard, but the groundwater and soils do pose enough of a threat that they need to be cleaned up.
The soil originally became contaminated early in the company's history, when chemicals would drip through the plant's wooden floors into leaky concrete troughs, which allowed the pollutants to seep into the ground, said Pam McCurdy, an MPCA spokeswoman.
Superior Plating has been cleaning up contaminants in the soil and water for years, McCurdy said.
McMonagle estimates that the company has spent $100,000 a year on investigation and remediation for the past 15 years.
"We have worked diligently to try to remediate the sins of the past," he said.
An affiliate of Minneapolis-based City Center Realty Partners has made a bid of $2.5 million for the Superior Plating site, which will be auctioned in February, McMonagle said. He said he was told City Center was interested in developing a retail and residential complex on the site. A City Center representative declined to comment.
The cleanup is expected to finish Thursday afternoon. Its cost is still unknown, but the MPCA will try to recover the money when the property is auctioned, McCurdy said.
Staff writer Susan Feyder contributed to this report.
Nicole Norfleet • 612-673-4495