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De Minimis Parties Agree to Reimburse EPA for Groundwater Cleanup Work at Omega Chemical Corporation Superfund Site in California

On May 14, 2020, the U.S. Environmental Protection Agency (EPA) reached an agreement with 143 de minimis parties that sent between one and three tons of waste for recycling or disposal between 1976 and 1991 to the Omega Chemical Corporation in Whittier, California. Under the settlement, the de minimis parties agree to pay the Agency more than $6.5 million for their past and future cleanup costs at the site. The money is expected to go toward cleanup work at the site to address contaminated ground water that extends beyond the property line and reaches the cities of Whittier, Santa Fe Springs and Norwalk, California. The settlement agreement became effective on July 1, 2020.

“We are pleased that this settlement will help address the groundwater contamination to which these companies and others have contributed, ensuring the protection of a vital drinking water source for LA County is one of the priorities in getting this site cleaned up.” EPA Pacific Southwest Regional Administrator John Busterud

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Information about the Omega Chemical Corporation

The Omega Chemical Corporation was a refrigerant and solvent recycling facility, located in Whittier, California that operated between 1976 and 1991. It handled drums and bulk loads of industrial waste solvents and chemicals that were processed to form commercial products.

Information about the Omega Chemical Corporation Superfund Site

The Omega Chemical Corporation Superfund site includes soil contamination at the former Omega Chemical facility in Whittier, California and an area of groundwater contamination extending at least four miles to the south and west. The Omega location became a Superfund site in 1999, when it was added to the Superfund National Priorities List. Since that time EPA has overseen the removal of more than 2,700 drums as well as more than 12,500 pounds of contaminants from the soil and groundwater. This effort has included treatment of more than 30 million gallons of contaminated groundwater since 2009. The groundwater contamination is believed to result from spills, leaks, and poor chemical handling practices at the Omega Chemical facility and at other industrial operations in the area.

Subsurface soil and groundwater at and around the site have high concentrations of trichloroethylene (TCE), perchloroethylene (PCE), freons and other contaminants. Consumption of high levels of TCE and PCE for extended periods of time can cause damage to the nervous system, liver and lungs and increase risk of cancer.

More information on the site is available from the Agency’s Omega Chemical Corporation Superfund site profile webpage. Press Release announcing settlement agreement (May 21, 2020)

Contact Information

For more information contact

Nicholas Sciretta
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue, NW
Washington, D.C. 20460
(202) 564-7416

Michael Massey
U.S. Environmental Protection Agency
Region 9
75 Hawthorne Street
San Francisco, CA 94105
(415) 972-3034

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