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News Releases from Region 09

EPA Reaches $56.6 million Settlement for Groundwater Cleanup at Los Angeles Area Superfund Sites

Settlement Will Continue Effort to Contain and Clean Up Large Area of Contaminated Groundwater

Contact Information: 
Alejandro Diaz (

LOS ANGELES – The U.S. Environmental Protection Agency (EPA), the U.S. Department of Justice and the California Department of Toxic Substances Control (DTSC) have reached a $56.6 million settlement with Montrose Chemical Corporation of California, Bayer CropScience, Inc., TFCF America, Inc., Stauffer Management Company LLC, and JCI Jones Chemicals, Inc. for further cleanup work of contaminated groundwater at the Dual Site Groundwater Operable Unit of the Montrose Chemical Corp. and Del Amo Superfund Sites (also known as the Dual Site) in Los Angeles County, California.

This work will include operating and maintaining the primary groundwater treatment system for the remedy selected in the 1999 Dual Site cleanup plan. The settlement also includes payment to EPA of $4 million in past costs, another payment of costs incurred by DTSC, and payment of EPA’s and DTSC’s future oversight costs

“This settlement ensures the long-term operation of the groundwater cleanup system,” said John Busterud, EPA’s Regional Administrator for the Pacific Southwest. “EPA is committed to the removal of contaminants from our groundwater in Los Angeles County.”

“DTSC is pleased with the strong collaborative partnership we have developed with the U.S. EPA team on this project,” said California Department of Toxic Substances Control Director, Meredith Williams. “We are looking forward to supporting U.S. EPA’s efforts and will continue to protect the state’s interests by making polluters pay for the cleanup.”

Groundwater at the Dual Site is contaminated with hazardous substances from industrial operations, including chlorobenzene from the former Montrose facility where DDT was manufactured, benzene from the Del Amo facility where synthetic rubber was manufactured, and trichloroethylene (TCE) related to several facilities. This settlement specifically addresses the chlorobenzene plume, which refers to the entire distribution of chlorobenzene in groundwater at the Dual Site and all other contaminants that are commingled with the chlorobenzene.

Cleanup activities will involve pumping the groundwater in the chlorobenzene plume and treating it to federal and State of California cleanup standards identified in the 1999 remedy. The treated water will then be reinjected into the aquifer outside of the contaminated groundwater area. The objective is to contain a zone of groundwater contamination surrounding source areas (also known as the ‘containment zone’) and clean up the chlorobenzene plume outside of that zone. Containment will occur soon after pumping operations begin, and cleanup of groundwater beyond the containment zone is expected to take approximately 50 years to complete. In addition, EPA will pursue settlements with other parties to conduct cleanup work selected for the benzene and TCE plumes in the Dual Site cleanup plan.

A consent decree formalizing the settlement was lodged on August 6th by the U.S. Department of Justice and is subject to a 30-day public comment period and approval by the federal court. The consent decree can be viewed at:

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