Congressional District # 05
FRIDLEY COMMONS PARK WELL FIELDEPA ID# MND985701309
Last Updated: August, 2012
The Fridley Commons Park Well Field Site (Site) is located in the city of Fridley, Minnesota. The Site is located approximately one mile east of the Mississippi River, one mile south of Rice Creek, and approximately 0.2 miles northeast of Moore Lake. The Site is about 50 acres in area. Surrounding land use is largely residential along with commercial/industrial businesses. The City of Fridley receives its municipal water supply from 13 municipal wells, 8 of which are located within the park along with a water treatment plant. The water supply provides water to a population of about 29,000 people.
The Fridley municipal water supply system is also supplemented by an interconnection to the New Brighton municipal water system. Primarily during the winter months, the interconnection provides excess water from the water treatment system installed at the Twin Cities Army Ammunition Plant.
Several geologic studies have been conducted in Fridley and the surrounding communities for environmental purposes. These studies have found that there are several aquifer systems in the region surrounding the Site. Of the eight municipal wells located within the park, Municipal Well Nos. 6, 7, 8, and 9 historically have been impacted by low levels of volatile organic contaminants (VOCs) consisting primarily of trichloroethylene (TCE) and are withdrawing water from the Prairie du Chien Jordan Aquifer (PdCJ). In addition to TCE, breakdown products of TCE (e.g. di-chloroethylene and vinyl chloride) have also been detected intermittently. The other four municipal wells (Municipal Well Nos. 2, 3, 4, and 5) are withdrawing water from the Mt. Simon-Hinckley aquifer and have not indicated evidence of contamination.
The source of contamination which had impacted the well field has never been identified. The city has been monitoring groundwater water quality on a regular basis. Drinking water with contaminant concentrations below the maximum contaminant level (MCL) do not pose unacceptable risks to public health from the exposure to TCE.
This site is being addressed through federal and state actions. The State of Minnesota through the Minnesota Pollution Control Agency (MPCA) is the lead regulatory agency on this site with support provided by United States Environmental Protection Agency (U.S. EPA).
Threats and Contaminants
Public water supplies are regulated by the U.S. EPA under the Federal Safe Drinking Water Act. Pursuant to the Act, U.S. EPA calculates the maximum contaminant levels (MCLs) based on the consideration of the health risk and the technical feasibility of the current remediation technologies for removing a specific contaminant. Historical ground water samples have indicated that some of the municipal water supply wells have been impacted by TCE at levels above its MCL of 5 ug/L.
In 1981, the City of Fridley initiated a program for measuring VOCs in groundwater samples from its municipal wells. TCE was detected in Well 9 in 1984, although it was not detected in the blended water of the water supply system. Subsequent testing indicated that the four PdCJ wells (Nos. 6, 7, 8, and 9) were impacted by VOCs consisting primarily of TCE.
The city undertook a study in an effort to identify the source of the contamination. Additional wells were installed, and a study of possible sources in the area of the well field was conducted. The source of the contamination was not identified and the shallow aquifer in the vicinity of the site was not impacted; however, VOCs were frequently present in samples from Well Nos. 6, 7, 8, and 9. Analyses indicated that Well No. 9 consistently had the highest concentrations and was taken out of service in February 1989. The City also reduced the use of Well Nos. 6, 7, and 8. The City's water supply has been partially supplemented by the New Brighton-Fridley Interconnect in an effort to replace the water that is no longer useable.
An evaluation of groundwater contamination was conducted under the direction of MPCA and a report was prepared in March of 1997. The report summarizes the geology, hydrogeology and the types and quantities of contamination detected along with long-term predictions, with regard to fate and transport of the contamination. The source of the contamination was not identified and the report concluded that unless TCE concentrations decline, treatment of the existing contaminated water or new sources of water will be needed to meet the future demands with water of acceptable quality.
In August 2000, EPA funded MPCA to complete a focused remedial investigation/feasibility study (RI/FS) and record of decision (ROD) for the site. The results of the investigation were inconclusive as to the source of the contamination. Further investigation was not considered beneficial and focus shifted to evaluating methods to provide the City of Fridley with an acceptable water supply. Meanwhile, the City of Fridley continues to monitor the municipal wells while they are in use. The results have indicated that the contaminant concentrations have remained below the MCL with the exception of Well No 9. Since 2004 the concentrations in Well No 9 have been below the MCL and TCE breakdown products are no longer being detected.
Since MPCA had been unable to identify a source of the contamination and contaminant concentrations have remained below health based levels for an extended period of time, a Record of Decision was signed in September 2005 recommending that a remedy was not required and that ground water monitoring be conducted for at least two years to ensure that unacceptable contaminant levels do not return. Recent data have shown that concentrations have remained below the MCL.
The site is currently being evaluated to determine if it is appropriate to de-list the site from the National Priorities List.
Community InvolvementThere has been little community interest in the site until 2012 when the Minnesota Department of Health (MDH) reported cancer rates in Fridley were higher for some cancers than the state expected rates. MPCA, MDH, the City of Fridley and U.S. EPA have increased activities to inform the public about contamination and exposure from this Site and other National Priorities List sites in Fridley and surrounding communities.
The site consisted of contaminated ground water located within the municipal well field in the Fridley Commons Park. Normal use of the park has not been restricted and the park continues to be utilized for recreational activities.
ContactsRemedial Project Manager, U.S. EPA
david seely (email@example.com)
Community Involvement Coordinator, U.S. EPA
AliasesFRIDLEY COMMONS PARK WELLFIELD