North Minneapolis Air Monitoring Project

The MPCA began a special project to monitor air quality in a heavily industrialized area of north Minneapolis in 2013. The project started as part of the MPCA’s process in re-issuing the air quality permit for Northern Metal Recycling, Inc., which operates a metal shredding facility south of the Lowry Avenue Bridge on the west bank of the Mississippi River. The project started with one monitor.

The air monitoring sites measure multiple air pollutants including total suspended particulates (TSP), coarse particulates (PM10), and air toxics (metals, VOCs, and carbonyls). The majority of air samples are collected for 24-hours once every six days. PM10 is collected hourly. To date, air monitoring has found violations of the state TSP standards, exceedances of the daily PM10 standard, and elevated metals concentrations at the monitors located adjacent to the Northern Metals facility.

Under a settlement that Northern Metals and the MPCA agreed to in Ramsey County District Court in March 2017, the company will move its metal shredding operation to a new location in 2019 (more info below).


  • January 2013 — The MPCA begins air monitoring for fine particles (PM2.5) at Lowry Avenue (909)
  • October 2014 — The MPCA adds TSP and air toxics monitoring to Lowry Avenue (909). In the first month of operation, the monitor violates the daily TSP standard.
  • June 2015 — Monitoring for TSP, PM10, and metals begins at Pacific Street (910)
  • January 2017 — Monitoring for TSP, PM2.5, metals, VOCs, and carbonyls begins at Bottineau/Marshall Terrace (1909)

Map of monitoring sites
Aerial map of North Minneapolis at Lowry Avenue over the Mississippi River

Air monitoring results

Elevated levels of airborne particulate and heavy metals have been measured at the Lowry Avenue and Pacific Street sites. Air monitoring results have identified:

  • Violations of the daily and annual Total Suspended Particulate (TSP) standards
  • Exceedances of the daily PM10 standard
  • Elevated lead concentrations, measured at 80% of the national lead standard
  • Elevated heavy metal concentrations including three metals (chromium, cobalt, and nickel) measured above chronic inhalation health risk benchmarks

Summary reports

Data reports (updated quarterly)

What the MPCA is doing

The MPCA is actively working to address the elevated air pollution levels in the area surrounding these monitors.

Air monitoring is continuing at the Lowry Avenue and Pacific Street sites (sites 909 and 910, respectively) and the MPCA is providing timely public access to results. In 2017, the agency added a third air-monitoring site on the east side of the Mississippi River in the Marshall Terrace neighborhood at 2522 Marshall St. NE.

In addition to addressing Northern Metals, the MPCA is working with the city of Minneapolis to identify other sources in the area that may be contributing to elevated air pollution levels, and to have these facilities take pollution-reduction measures to improve air quality. These activities include increasing the frequency of site and street spraying and sweeping, moving activities indoors, and changing material-handling practices.

Northern Metals is no longer operating the Metals Recovery Plant portion of the facility. The company has made modifications to the shredder building to increase the capture of emissions and has conducted testing to demonstrate that the building is capturing emissions at levels required by the permit. Northern Metals has now demonstrated, through third-party testing of the shredder building stack’s emissions, that the shredder is not emitting particulate matter or other pollutants in excess of its permitted limits.

Court settlement

Northern Metals Recycling was ordered by Ramsey County District Court to cease operation of the Metals Recovery Plant effective September 2, 2016. Subsequently, on February 28, 2017, Northern Metals, the MPCA and the City of Minneapolis signed a court-overseen agreement (Consent Decree) requiring the facility to relocate its shredding operation by no later than August 1, 2019.

For more information