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Congressional District # 05


EPA ID# MND053417515
Last Updated: December, 2012

Site Description

The Boise Cascade/Onan/Medtronics site covers 183 acres in Fridley, Minnesota. The National Pole and Treating Company and later the Minnesota and Ontario Paper Company treated wood from 1921 until 1961 at this location. Operations at the site first used creosote to treat wood for railroad ties and for utility poles. The company began using pentachlorophenol (PCP) to treat its wood products in 1958 and continued this practice until 1961, when all operations stopped. In 1965, the Minnesota and Ontario Paper Company was purchased and merged into the Boise Cascade Company. The Onan Corporation acquired 133 acres of the Boise Cascade property and Medtronic, Incorporated purchased the remaining 50 acres. These new owners obtained the property to build commercial and manufacturing facilities on the site. In 1979, Onan and Medtronic uncovered large quantities of creosote from past treatment operations. Approximately 3,000 people lived within one mile of the site. Several residences were located within 500 feet of the site. Two elementary schools and several small urban parks were located within one mile of the site at the time of the investigation. Fridley had a population of about 27,000 in 2010.

Site Responsibility

This site was addressed through federal, state, and potentially responsible party (PRP) actions. 

Threats and Contaminants

The U.S. EPA detected high levels of organics, including creosote and phenols, in on-site groundwater monitoring wells, sediments, and soils. Long-term groundwater monitoring continues through the present.

Cleanup Progress

In January 1984, Medtronic entered into a consent decree (CD) with the state to address the contamination on its part of the site. Onan Corporation, Boise Cascade, and two railroad companies went to court concerning site responsibility disputes and a solution to the contamination on the Onan property. An injunctive order was issued by the court in December 1984.

On the Onan property, the work included: (1) a slurry wall containment system constructed around the former retort building into which excavated contaminated soil was placed; (2) a cap was constructed over the area surrounded by the slurry wall; (3) dewatering; and (4) treatment of the water prior to discharge. On the Medtronic property, where two wastewater lagoons had been operated, contaminated soils were excavated and disposed of off-site. Groundwater that was in contact and directly beneath contaminated soil was collected, treated, and discharged. About 5,000 gallons of oil was collected and disposed of off-site. For both properties, long-term groundwater monitoring was undertaken.

The PRPs completed cleanup activities in 1992. Medtronic constructed an office building and parking lot on the western part of the site and the Onan Corporation, later to become a subsidiary of Cummins, Inc., constructed an office building, manufacturing facility, and parking lots on the eastern part of the site. EPA deleted the site from the NPL in 1995.

In 1999, the south-central part of the Onan property was further developed with the Murphy Warehouse building and its associated parking areas and a storm water retention pond. Volatile organic compounds (VOCs) were detected in the soils during construction. Drums and impacted soil were removed and impacted groundwater was monitored for about two years. In 2009, Cummins began investigating the northeastern part of the Onan portion of the site before constructing a new Generator Test Cell Facility. A layer of black-stained soils was encountered at a depth ranging from 6 to 9 feet below ground surface. Elevated concentrations of diesel range organics (DROs), polycyclic aromatic hydrocarbons (PAHs) and PCP were detected. Some of the impacted soil was removed, but some was left in place. The Test Cell Facility, consisting of a slab-on-grade building, parking, utility trenches, and stormwater ponds, was constructed in 2010 and 2011. A vapor barrier and subslab venting system were installed below the new Facility.

The first five-year review report was completed on September 15, 1999. A second five-year review report, prepared by the Minnesota Pollution Control Agency (MPCA), was completed in September 2004. A third , also prepared by MPCA, was completed in August 2009. This MPCA review concluded that the monitoring indicates that the contaminant plume is decreasing in lateral and vertical extent. There are no known drinking water wells that are impacted by the contaminant plume. The remedy is functioning as intended and is protective of human health and the environment in the short- and long-term.


Remedial Project Manager, U.S. EPA
gladys beard (beard.gladys@epa.gov)
(312) 886-7253

Community Involvement Coordinator, U.S. EPA
teresa jones
(312) 886-0725




Site Profile Information

This profile provides you with information on EPA's cleanup progress at this Superfund site.


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