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Case Summary: EPA Orders FMC to Perform $57 Million Cleanup Action at Former Phosphorus Processing Facility in Idaho

On June 10, 2013, EPA issued a unilateral administrative order (UAO) for remedial design/remedial action (RD/RA) to FMC to implement an interim response action, estimated to cost $57 million, to address contamination at its former phosphorus processing facility that is located within the boundaries of the Fort Hall Indian Reservation in Idaho. The work being performed under this Order will control exposures to more than 45.7 million yards of contaminated soil.

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Information about FMC Corporation

FMC Corporation is a publicly traded specialty chemical company founded in 1883. Its products are used in various industries including agriculture, food and beverage production, pharmaceuticals, and energy.

Information about the Eastern Michaud Flats Superfund Site

The Eastern Michaud Flats Superfund Site covers approximately 2,530 acres northwest of Pocatello, Idaho. It includes two adjacent phosphate ore processing facilities. The FMC operable unit (OU) consists of approximately 1,450 acres.  The FMC Corporation operated its facility within the FMC OU from the 1940’s until December 2001.  The adjacent JR Simplot Company produces phosphate fertilizers and is still operating.

The FMC facility was an elemental phosphorus manufacturing facility.  While it was in operation, elemental phosphorus containing wastes were disposed of in ponds, some of which were RCRA regulated and are being addressed under a 1999 Resource Conservation and Recovery Act (RCRA) Consent Decree, while others are covered by the 2013 CERCLA UAO.  Other portions of the facility are contaminated with elemental phosphorus and other hazardous substances in soil from spills and other releases.  In addition, slag from the production of elemental phosphorus emits elevated levels of gamma radiation. Finally, groundwater is also contaminated primarily with phosphorus compounds and arsenic and is a source of contamination to the Portneuf River.

Additional information is available on the Eastern Michaud Flats Contamination Superfund Site web page

Pollutants and Environmental Effects

Soils and groundwater in the FMC OU contain ignitable-reactive elemental phosphorus-containing wastes and other hazardous substances. The former waste ponds (both CERCLA and RCRA) and other areas of contaminated soil are being covered with Evapotranspiration (ET) Caps to prevent precipitation infiltration and migration of these hazardous substances toward and into the Portneuf River.  The caps also securely contain the wastes within the former waste ponds and prevent contact with human and other terrestrial receptors.

Elemental phosphorus (P4) is a RCRA ignitable and reactive waste that burns upon contact with air thereby requiring special handling techniques. The interim remedy that is being implemented by this UAO addresses these risks through containment by capping.  The interim remedy also addresses gamma radiation exposures in slag and other soils, and phosphorus loading to the Portneuf River by extracting and treating contaminated groundwater

Summary of the Unilateral Administrative Order

The UAO requires FMC to perform the selected interim remedy and to pay EPA’s oversight costs. It also requires FMC to share information with the Shoshone Bannock Tribes and provide opportunities for input by the Shoshone Bannock Tribes.  EPA is funding the Tribes’ participation in the implementation of the UAO through a cooperative agreement.

Contact Information

Charles Ordine
Region 10
U.S. Environmental Protection Agency
1200 Sixth Avenue
Seattle, WA 98101

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