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Case Summary: $78 Million Clean Up Settlement will address Groundwater Contamination at Southern California Superfund Site

On March 31, 2017, the United States District Court for the Central District of California approved and entered the consent decree between the U.S. Environmental Protection Agency (EPA), the Department of Justice, and a group of 66 companies to clean up contaminated groundwater at the Omega Chemical Corporation Superfund Site in Whittier, Calif. The settlement requires the companies to spend an estimated $70 million to install wells and operate a groundwater treatment system. In addition, the parties will reimburse EPA $8 million and the California Department of Toxic Substances Control $70,000 toward costs incurred in those agencies’ past cleanup actions at the site.

The groundwater cleanup required by the settlement will protect a vital drinking water source for Los Angeles County and the cleanup of this polluted aquifer is critical since the groundwater in the region has been depleted because of the drought conditions in California. The cleanup will address 200 million cubic yards of contaminated groundwater.

The 66 settling parties will conduct the cleanup work. An additional 171 parties have either sent waste to the site or operated in the area and contributed to the contamination have also agreed to fund a portion of the work.

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Information about the Omega Chemical Corporation Superfund Site

The Omega Chemical Corporation Superfund site (“Omega Superfund site”) was placed on the National Priorities List in 1999 and extends from Whittier through Santa Fe Springs and into Norwalk, Calif.

The former Omega Chemical Corporation facility operated from approximately 1976 to 1991 and was across the street from a residential neighborhood and within one mile of several schools. The facility handled drums and bulk loads of industrial waste solvents and chemicals that were processed to form commercial products.

Over the last 20 years, EPA has overseen the removal of more than 2,700 drums as well as more than 9,000 pounds of contaminants from the soil and groundwater. A soil vapor extraction system to address vapor intrusion from the Omega Superfund site has been operating since 2010. A small groundwater pump and treatment system has treated more than 30 million gallons of contaminated groundwater near the Omega Chemical facility since 2009.

More information is available from the Omega Chemical Corporation Superfund site profile sheet.

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Information on pollutants and environmental effects

Subsurface soil and groundwater have high concentrations of trichloroethylene (TCE), perchloroethylene (PCE), Freons and other contaminants. Drinking high levels of TCE and PCE for extended periods of time could cause damage to the nervous system, liver and lungs and increase risk of cancer.

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Summary of the consent decree

The settlement, in the form of a consent decree, requires the settling parties to implement the cleanup remedy required by EPA’s 2011 Record of Decision for three miles of the groundwater plume. The settling parties will also install and sample groundwater monitoring wells to investigate and evaluate the remaining contaminated area at the site to determine what additional remediation is needed.

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Contact information

For more information, contact

Hope Schmeltzer
Office of Regional Counsel
U.S. Environmental Protection Agency
Region 9
75 Hawthorne Street
San Francisco, CA  94105

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