The Ralph Gray Trucking Co. site covers 23 acres in Westminster, California. Starting in 1936, acid sludge, oil field wastes, and oil refinery wastes were dumped into four unlined pits at a former dairy farm. A development company later buried those hazardous substances in two unlined trenches beneath roughly 25 homes built in the late 1950s. When black sludge and seep material began appearing in residents' yards, EPA added the site to the National Priorities List (NPL) on October 14, 1992.
Contaminants include volatile organic compounds (VOCs), sulfur compounds, and polycyclic aromatic hydrocarbons (PAHs). These pollutants affected surface seep material, buried waste, soil, and groundwater. The main health concern was people ingesting, inhaling, or touching contaminated soil and groundwater. Between 1987 and 1991, the California Department of Health Services removed seep material annually and issued health advisories to protect nearby residents.
Cleanup work was organized into three operable units (OUs), which are distinct areas or problems addressed separately. The main removal action began in 1992. A contractor excavated about 45,000 cubic yards of hazardous material, replaced it with clean backfill, and made landscaping improvements. Several homes built directly above waste deposits were demolished and rebuilt. EPA restored affected yards and compensated homeowners for demolished structures. All restoration work finished by 1997, and construction across the full site was completed on August 31, 2000. The U.S. Bureau of Reclamation provided temporary relocation help for affected residents during the work.
EPA has determined that human exposure is under control and that contaminated groundwater is stabilized in its original area, with no unacceptable discharge to surface water. Post-cleanup sampling confirmed contamination does not pose a risk to human health or the environment. EPA notes that deeper soil excavation could potentially uncover small pockets of remaining waste material. The site was deleted from the NPL on September 28, 2004, and achieved sitewide ready for anticipated reuse status on June 26, 2006. The Superfund Redevelopment Program continues to work with the community to support productive reuse of the site.
Community members with questions can contact the Community Involvement Coordinator or the Remedial Project Manager.
