Breaking News
More () »

MPCA: Investigation shows 3M mismanaged hazardous waste at Cottage Grove facility

State officials say the investigation uncovered a series of violations dating back to 1996 relating to hazardous waste storage and disposal.

COTTAGE GROVE, Minn. — Minnesota-based 3M will pay a civil penalty of more than $2.8 million and take a number of corrective steps following a state investigation into storage and disposal of hazardous waste at a facility in Cottage Grove. 

The Minnesota Pollution Control Agency (MPCA) announced the findings of the investigation, which began in June of 2022, during a media briefing Thursday. It involves what investigators say is a series of violations at 3M's facility in Cottage Grove, a location that stored and incinerated hazardous waste from all 3M operations in North America until it closed on December 31, 2021.

Among the violations MPCA investigators say they uncovered: 

  • In 1996, 2006, 2012-2014, 2017-2018, and 2020-2021, 3M inaccurately identified hazardous waste sent to its incinerator as "non-hazardous" waste.
  • Over the course of 109 weeks between 2015 and 2020, 3M failed to have a certified third-party lab verify the accuracy of the incinerator laboratory’s analysis, as required by permit.
  • From 2014 to 2020, 3M failed to conduct verification on more than 1,800 waste stream profiles for mercury, lead, nickel, cadmium, arsenic, and other hazardous materials to ensure the waste did not exceed permit limits.
  • Since 2016, 3M failed to require two third party vendors that sent waste to the Cottage Grove incinerator to submit data for arsenic, PCBs, lead, mercury and other hazardous materials.
  • 3M stored approximately 1,300 containers of hazardous waste in unapproved areas, 650 of which were stored for longer than the one-year limit.

As a result of the state investigation MPCA says 3M has completed 24 corrective actions that include increasing container storage inspections, keeping hazardous material records onsite and increasing verification of its waste streams with independent state-certified labs. 

In May of 2021 MPCA launched a separate investigation at the same facility after a container of hydrofluoric acid, an extremely toxic chemical compound, was found releasing gases into the air. Investigators discovered an additional 901 hazardous waste vessels containing the same dangerous chemical on site, some with bulging barrel lids. 

Investigators say 3M failed to immediately notify the MPCA of the situation, and risked emissions that could have endangered human health. As a result of the 2021 investigation, 3M agreed to pay a civil penalty of $80,000 and make corrective measures.

Watch science and WeatherMinds:

Watch the latest deep-dives and explainers on weather and science in our YouTube playlist:

Before You Leave, Check This Out