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Date of incident: Late 1940s to early 1970s; litigation was initiated in 1990.
Location: The marine environment of the Southern California Bight, including the Channel Islands (see figure).
Case status: Case settled. In restoration.
Overview: From the late 1940s to the early 1970s, millions of pounds of DDTs and
PCBs were discharged into ocean waters off the Southern California coast. Almost all of the DDTs originated from the Montrose Chemical Corporation's manufacturing plant in Torrance, California, and were discharged into the Los Angeles County Sanitation Districts' (LACSD) wastewater collection system. The DDT-contaminated wastewater was discharged for years through the wastewater outfall into the Pacific Ocean off White Point, in a submarine area known as the Palos Verdes Shelf. Montrose also dumped hundreds of tons of DDT-contaminated waste into the ocean near Santa Catalina Island. Additionally, large quantities of PCBs (polychlorinated biphenyls) from numerous sources throughout the Los Angeles basin were also released into ocean waters through the LACSD's wastewater outfall on the Palos Verdes Shelf.
In 1992 and 1993, surveys by the U.S. Geological Survey (USGS) found that more than 100 metric tons (110 U.S.
tons) of DDTs and 10 metric tons (11 U.S. tons) of PCBs remained in the
sediments at the ocean bottom of the Palos Verdes Shelf. The highest
concentrations of DDTs and PCBs were near the mouth of the White Point
wastewater outfall, at depths of 40 to 80 meters (130 to 260 feet). Subsequent
surveys by the Southern California Bight Pilot Project showed that elevated
concentrations of DDTs and PCBs in bottom sediments extended from the Palos
Verdes Shelf into Santa Monica Bay (see figure).
the U.S. government and the state of California filed a lawsuit
under the federal Superfund law alleging that a number of defendants
were responsible for releasing DDTs, PCBs, and other hazardous
substances into the environment. The lawsuit charged that DDTs and
PCBs injured natural resources, including fish and wildlife that
live in and around coastal waters in Southern California.
Numerous independent studies have shown that DDTs and PCBs still contaminate marine life and birds in Southern
California and continue to harm these natural resources and the services they
The final consent decree settling this lawsuit was entered into on March 15, 2001. The natural resource trustees have
formed the Montrose Settlements Restoration Program (MSRP) to plan and conduct
restoration of injured resources and lost services. Because DDTs and PCBs
persist in the marine environment at levels that continue to cause injuries,
MSRP has been conducting "data gap" studies to gather information on fish
contamination, fishing practices, and the potential for bald eagle and
peregrine falcon restoration in the Channel Islands.
The MSRP Restoration Plan and Programmatic Environmental Impact Statement (EIS) and
Environmental Impact Report (EIR) describes the trustees' preferred
course of action to address the restoration of the natural resources.