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U.S. EPA reaches major settlement for cleanup of San Gabriel Valley Superfund site

Release Date: 08/27/2009
Contact Information: Francisco Arcaute, (213) 244 1815,

For Immediate Release: August 27, 2009
Contact: Francisco Arcaute
(213) 244-1815, Cell (213) 798-1404

U.S. EPA reaches major settlement for cleanup of San Gabriel Valley Superfund site
Agreement calls for $21 million groundwater treatment system, will provide drinking water

LOS ANGELES – The U.S Environmental Protection Agency has reached a settlement with Northrop Grumman Space & Mission Systems Corporation (“Northrop Grumman”), two related entities, and 43 cash-out parties that requires Northrop Grumman to cleanup groundwater contamination at the Puente Valley Operable Unit of the San Gabriel Valley Superfund Site, Area 4, in Southern California.

Northrop Grumman, representing all of the settling defendants, will spend an estimated $21 million to build a groundwater cleanup system that uses wells to pump out contaminated groundwater, preventing it from further migration. Northrop Grumman will also install water conveyance pipelines and construct a treatment plant to remove Volatile Organic Compound (VOC) contaminants from the groundwater. The treated water will be used for drinking water supply, water reclamation projects, or discharged to surface water.

“This settlement requires cleanup of the groundwater at the Puente Valley Operable Unit Superfund Site, which is an important step toward restoring this valuable source of drinking water,” said Keith Takata, director of the Superfund program of the U.S. EPA’s Pacific Southwest Office.

The Puente Valley Operable Unit of the San Gabriel Valley Superfund Site, Area 4, is an area of contaminated groundwater located beneath the City of Industry, the cities of La Puente and Walnut, and portions of unincorporated Los Angeles County. The groundwater was contaminated by over 60 source properties that used VOCs for degreasing, metal cleaning and other purposes. The EPA listed several areas of contaminated groundwater within the San Gabriel Valley as Superfund sites in 1984.

The contaminated groundwater associated with all of the San Gabriel Valley Superfund sites lies under significant portions of Alhambra, Irwindale, La Puente, Rosemead, Azusa, Baldwin Park, City of Industry, El Monte, South El Monte, West Covina, and other areas of the San Gabriel Valley. There are 45 water suppliers in the Valley that use the San Gabriel Basin groundwater aquifers to provide 90 percent of the drinking water for over one million people.

Northrop Grumman has already spent over $10 million implementing the intermediate zone remedial action in compliance with an order EPA issued on March 21, 2002. The settlement also provides for reimbursement of $465,420.90 to EPA, and $90,000 to the California Department of Toxic Substances Control for past costs.

The work to be performed by Northrop Grumman on behalf of all of the Settling Defendants implements a substantial portion of the EPA's interim site cleanup plan. Other portions of the cleanup plan are being addressed by other responsible parties. The Northrop Grumman Consent Decree is the 9th Consent Decree for the site. The total value of the all of the work and settlements for the performance of the interim clean up exceeds $70 million.

The EPA will ultimately develop a final cleanup plan for the site following several years of expected compliance and operational monitoring of the interim remedy.

For more information on the EPA’s Superfund program, visit:
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