Pacific Coast Pipeline

Investigation and Cleanup Activities

This site is being addressed in two stages: immediate actions and a long-term remedial phase focusing on cleanup of the entire site.

Initial Actions

Immediate Actions: In 1986, Texaco excavated the main waste pit and other smaller areas and transported the soil to a federally approved hazardous waste storage facility.

Cleanup Ongoing

Entire Site: Pacific Coast Pipeline conducted an investigation into the nature and extent of contamination at the site under EPA oversight. A cleanup remedy was selected in 1992 that called for groundwater treatment through solvent extraction. Treatability studies and the design of the remedy were completed in 1994. Cleanup actions began in 1995. Two extraction wells were installed to pump groundwater contaminated primarily with benzene, which was then removed from the water by a carbon treatment system. A soil vapor extraction system (SVE) was installed to remove contaminants from two hot spots to protect groundwater. Additional investigation of soil and soil gas has been done at the site subsequent to the groundwater ROD; a ROD Amendment is planned to address final site remedial actions. The second five year review was completed in September 2006.

Benzene concentrations in soil gas decreased by 96% between 1997 and 2002. By January 2002 the SVE system had accomplished its goal, which was to reduce the level of benzene in soil so it would no longer migrate down to the groundwater. The SVE system was shut off, soil gas concentrations were monitored for 8 months, and no re-bound above the shut-off criteria was observed. Soil vapor monitoring was discontinued in November 2002.

The extraction wells reduced benzene concentrations in the groundwater but elevated levels remained in the center of the two plumes. In 2002 the groundwater extraction system was shut off so Texaco could conduct a pilot study. In 2003-2004 Texaco conducted a pilot project that involved injecting Oxygen Release Compound, a magnesium peroxide compound, into the groundwater at the two plumes in order to help break down the benzene and speed up the cleanup. This pilot test performed below expectations so this treatment was not pursued. EPA will select another cleanup remedy to amend the groundwater ROD.

2002 was the last year the crude oil pumping station operated at the site. By 2004 the last above ground storage tank had been removed. Soil sampling conducted in this area indicates that contaminants remain in the soil above health based levels. PAHs, arsenic, and organic lead were detected above soil Regional Screening Levels. EPA will prepare a final ROD to address this contamination.

Cleanup Ongoing

Cleanup Ongoing

Cleanup Ongoing

Remedy Selected

On September 20, 2011, the third Five Year Review determined that the remedy at the Pacific Coast Pipeline Superfund Site is currently protective of human health and the environment. There is currently no exposure to the contaminated groundwater as no one is drinking or using groundwater impacted by the Site. Access to the property is restricted, so exposure to contaminated soil is limited.

For long-term protectiveness and to make the property ready for reuse, the Record of Decision was amended on September 29, 2012, to implement final soil and groundwater remedies, as follows:

Ground Water Cleanup Selected

A multi-phase cleanup approach will be taken to address the long-term groundwater cleanup at the site. This cleanup remedy is expected to reach cleanup goals in the southern plume in 25 years. The northern plume, which has less benzene, will be cleaned up using Monitored Natural Attenuation, which will take approximately 50 years to reach the cleanup goal. Specifically, the remedy includes:

Air Sparging: Air will be injected into the groundwater in the southern plume to stimulate naturally occurring bacteria to break down the benzene.

Groundwater Circulation: Pumps will circulate the groundwater in the southern plume, to move underlying sulfate rich waters into the benzene plume. The sulfate will boost bacteria growth, which will continue to break down the benzene in the groundwater.

Monitored Natural Attenuation: This phase involves reliance on naturally occurring processes in the northern plume to break down the benzene and sampling groundwater monitoring wells to ensure this process is effective.

Soil Cleanup Selected

The soil at the former refinery has lead and polycyclic aromatic hydrocarbons (PAHs) in various locations across the property. The contaminated soil will be excavated and disposed of in an on-site pit, which will be capped. After the soil cleanup is complete, the property can be used for commercial and recreational uses only.

For both groundwater and soils, Institutional Controls will be implemented under the ROD amendment, to limit use of property to commercial and recreational use and prohibit use of groundwater until cleanup levels are achieved.

Please review cleanup schedule through October 2013 under the "Document and Reports" section below.