Location: Carson, California Client Los Angeles County, Department of Public Works

The newly constructed storm drain runs along Sepulveda Boulevard west of the Dominguez Channel in the City of Carson. The site is located between five major oil refineries, and their product storage and loading terminals. Approximately 40 to 60 separate underground product pipelines and utilities exist within Sepulveda Boulevard, in any one given area.



The Los Angeles County Department of Public Works (LACDPW) constructed the Sepulveda/Dominguez storm drain improvement. The actual storm drain is made of a reinforced concrete box (12 feet by 9 feet), approximately 2,600 feet long. Aligned along Sepulveda Boulevard, the drain discharges into the Dominguez Channel. Approximately 30,000 cubic yards of soil impacted by petroleum hydrocarbons required excavation and remediation.

Leighton conducted limited soil and groundwater investigations from August 1990 through August 1992, confirming that the soil and groundwater required remediation. Fuel-range hydrocarbons and volatile aromatics existed in the soil and in the groundwater.

Leighton and Associates conducted a geophysical investigation (ground-penetrating radar) to aid in the identification of underground fuel pipelines/utilities, prior to the initiation of storm drain construction. In addition to documenting utilities, 24 anomalies were also detected.

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