Congressional District # 05
FMC CORP. (FRIDLEY PLANT)EPA ID# MND006481543
Last Updated: May, 2015
The 18-acre FMC Corp. Fridley Plant (FMC) site is located in Anoka County, Minnesota, approximately six hundred feet east of the Mississippi River. Solvents, paint sludge, and plating wastes were generated and disposed of in several locations at the FMC site from the 1940s until 1969. The Minnesota Pollution Control Agency (MPCA) sampled site soil and groundwater in the early 1980s and confirmed that soil and groundwater were contaminated by industrial solvents. In the 1980s, volatile organic compounds (VOCs) were detected in the City of Minneapolis drinking water system intake that is located downstream of where the FMC site groundwater contaminant plume enters the river.
Soil impacted by VOCs greater than 1 part per million (ppm) was excavated and placed into an on-site Containment Treatment Facility (CTF). VOCs, most commonly trichloroethylene (TCE) and metals, were detected in soil samples collected at the site. Soil contamination was addressed through the construction and completion of the CTF to contain and treat contaminated soil. Impacted soil was excavated to the water table and placed into the engineered, double-lined CTF cell located on the east central portion of the site. The removal action was undertaken to comply with the 1983 Administrative Order by Consent. The soil removal and containment successfully controlled risk to human health and the environment associated with soil contamination at the site.
Regular sampling of the water from the intake has shown no exceedences of contaminants since the 1980s. Because of the threat posed to Minneapolis drinking water, this site received one of the highest Hazard Ranking System (HRS) scores of all sites on the National Priorities List (NPL). The U.S. Environmental Protection Agency (EPA) proposed the site for the NPL in December 1982 and finalized the site on the NPL in September 1983.
Cleanup work at the FMC site was initiated in the 1980s, and four of the five groundwater extraction wells that were installed as part of the remedy have been in operation since that time. The inactive extraction well (RW-1) could not sustain a continuous pumping rate and ultimately went dry resulting in the deactivation of this well in 1987.
Site ResponsibilityThe FMC Corp. Fridley Plant site is being addressed by potentially responsible party (PRP) actions under state and federal oversight.
Threats and ContaminantsFMC site groundwater is contaminated with VOCs, with TCE as the primary chemical of concern (COC). Soil that was excavated in the 1980s was also contaminated with VOCs, including TCE; however, the excavated soil is addressed separately through the permitted CTF. The primary health risk at the FMC site is the potential use of contaminated groundwater as a drinking water supply. TCE believed to be from the site was detected in high concentrations in groundwater wells located near the Mississippi River and is believed to have contributed to the detection of VOCs in the Minneapolis drinking water supply intake in the 1980s. However, no exceedences of VOCs have been detected in the intake since the 1980s. In addition, because no private drinking water wells are in the area, no residents are directly exposed to the contaminants in the site groundwater .
The selected remedy for the FMC site is documented in the following decision documents:
- Minnesota Enforcement Decision Document (Oct.16, 1986)
- Response Order by Consent (Oct.28, 1986)
- Record of Decision (Sept.30, 1987)
- Explanation of Significant Differences (Sept.13, 2013)
The soil cleanup at the FMC site and installation of groundwater extraction wells were completed between 1983 and 1987. The 1987 Record of Decision documented the selection of the groundwater remedy for the site.
In addition to storing contaminated soil in an on-site vault, the cleanup also includes pumping contaminated groundwater and treating it on-site through air stripping. Treated groundwater is discharged under a National Pollutant Discharge Elimination System (NPDES) permit. Routine monitoring of groundwater began in 1987 and continues to this day. Although concentrations of VOCs in groundwater have decreased in most monitoring wells, pumping will continue until cleanup goals have been met.
MORE DETAILS ABOUT 1980s CLEANUP
On June 8, 1983, MPCA approved an Administrative Order on Consent (AOC) and interim Response Order by Consent among MPCA, EPA, and FMC. These orders provided for the excavation and placement of contaminated soil in an on-site vault. Construction of the containment facility began in May 1983. Approximately 38,600 cubic yards of contaminated soil were excavated from a 2.3 acre portion of the site and placed in the vault by July 1, 1983. The vault is monitored under a Resource Conservation and Recovery Act (RCRA) permit, issued to FMC Corporation by the MPCA. The RCRA permit was reissued by the MPCA in 2012.
Additional investigation, required under the orders, indicated that the unconfined and confined glacio-fluvial aquifers, comprising an area of approximately 25 acres, were impacted by industrial solvents. The aquifers discharge directly to the Mississippi River. In May 1985, FMC submitted a groundwater cleanup feasibility study which presented the different options for addressing the groundwater contamination.
A Response Order by Consent was executed between MPCA and FMC in October 1986 to address the contaminated groundwater. A groundwater pumpout system, consisting of five pumpout wells, was approved by MPCA. Construction was completed, and the system became operational on December 8, 1987. One well, RW-1, was shut down in 1988 due to insufficient water to maintain pumping in the well. The site is currently in long-term operation and maintenance of groundwater pumpout and monitoring. Improvements to the system have been made over time.
CHANGE IN GROUNDWATER TREATMENT METHOD
In 2013 the PRP implemented a change in the groundwater treatment method. Extracted groundwater had been discharged to the sanitary sewer for eventual treatment at the publicly owned treatment works, but is now being treated onsite via an air stripper, with treated water discharged to the storm sewer. The MPCA approved the change as the PRP obtained an NPDES permit and the treatment system meets the PRP’s Air Quality permit requirements. MPCA and EPA issued an Explanation of Significant Differences in September 2013 to document this change to the remedy.
Currently, the PRP is conducting a pilot test to determine the efficacy of Enhanced Reductive Dechlorination as a possible source remedy at the site. If the pilot test is determined to be successful, and can be implemented throughout the source area, it should help to shorten the operational duration of the existing groundwater containment remedy at this site.
FIVE-YEAR REMEDY REVIEWS
Because contamination remains on site, reviews of the cleanup remedy are required every five years to ensure the remedy remains protective of human health and the environment. The fifth five-year review for the site was completed in fall 2014. A protectiveness determination for the selected remedy was deferred until further information is obtained about the potential risk from vapor intrusion. Vapor intrusion sampling had been conducted at the Minneapolis Water Works (MWW) and initial data showed a potential for vapor intrusion concerns. Further information will be obtained to determine whether the vapor intrusion pathway is complete and whether vapor intrusion poses an unacceptable risk. It is expected that these actions will take approximately twelve months to complete, at which time a protectiveness determination will be made. An addendum to the fifth five-year review is expected in fall 2015.
Property ReuseIn 2009, BAE Systems installed 16 solar panels on the site, which provide 30 percent of the electrical energy needed for the remediation system on the south side of the site. The amount of energy produced per year would supply enough power for four average-sized homes. The use of solar energy at the FMC site prevents 41,000 pounds of carbon dioxide from being produced and emitted into the air.
ContactsRemedial Project Manager, U.S. EPA
sheila desai (email@example.com)
Community Involvement Coordinator, U.S. EPA
AliasesFMC CORP NIROP-US NAVY
FRIDLEY NAVAL INDUSTRIAL RESERVE ORDNANCE PLANT