Air monitoring project at 3M-Cottage Grove winds down
Cottage Grove is giving the all-clear to wrap up a 3M-related air monitoring project.
The city likely will discontinue monthly ambient air testing that was started two years ago, after 3M-Cottage Grove received regulatory approval to burn outside industrial waste at its incinerator.
Sampling has not found any concerning levels of pollutants related to the broadened incinerator use, according to the city.
“We’ve had no issues, so that’s why we don’t see any reason to continue,” Cottage Grove City Engineer Jennifer Levitt said.
The city has gathered two air samples randomly each month, using equipment set up on 3M property. One tests for the presence of metal particulates in the air, such as nickel, aluminum and mercury. The other measures the level of volatile organic compounds released as part of the company’s incineration process. The city contracted with a lab to gather and compile the data.
“The results are not concerning by any means,” Levitt said. “All things are within allowable limits by the (Minnesota Pollution Control Agency).”
Sampling has been done in conjunction with the MPCA’s statewide air monitoring, so Cottage Grove can compare its data against results gathered in other areas of the Twin Cities and elsewhere in Minnesota.
3M has provided information about what it was burning at the time of each sampling. That has helped to understand the correlation between the incineration process and particulate levels at the time, Levitt said.
Aside from a couple of testing anomalies that were later explained, “typically it’s been like watching grass grow,” City Administrator Ryan Schroeder said.
Ambient air monitoring has cost $78,400 each year. 3M has paid $60,000 and Cottage Grove’s portion has been $18,400. The city had an option for a third year of monitoring, but Schroeder said Cottage Grove did not budget for it in 2015 because the sampling has not shown any “adverse air quality.”
The city’s Environmental Commission will receive the final air monitoring results, gathered in June, at a Sept. 10 meeting. The commission also will review the overall two-year project and is expected to recommend ending the program.
The City Council is expected to vote Sept. 17 on whether to discontinue monitoring.
The expanded use of 3M’s waste incinerator inflamed some in the community. The company sought state approval to burn non-3M industrial waste because it was not generating enough waste at the Cottage Grove plan to run the incinerator efficiently. Opponents were concerned about air pollution from the expanded use.
Mayor Myron Bailey said he supports the proposal to end air monitoring, though he acknowledged some residents may not be satisfied.
“The state is showing there’s no issues, but there’s still some people that have that trust factor,” he said.
Bailey said city relations with the company have improved.
“I think we’re at a point in our relationship between the city and 3M where we can start regaining some of that trust between each other.”