Oxnard officials said this week that they expect state approval of their plans for a $6-million project to dispose of toxic soils on land slated for a massive complex of business parks in the northeast end of town.
Assistant Public Works Director Ben Wong also said the Regional Water Quality Control Board would probably approve the city’s plans to use the city’s waste-water treatment plant to dispose of ground water in the area that has been tainted with petroleum.
Engineers told City Council members Tuesday that they hope to truck soils contaminated with crude oils to a nearby landfill or to aerate the contaminated soil, which would then be buried under roadways or parking lots.
However, Chuck Hodges, an engineer overseeing the board’s study of the situation, said he plans to ask the city to truck the soils to a toxic-waste landfill. Hodges also said he plans to ask for additional testing of ground water in the area.
“They haven’t adequately determined the extent of ground water contamination,” Hodges said.
Testing so far has been contained to the storm channels draining the 1,600-acre area. They follow the routes of defunct and deteriorating oil pipelines along 5th Street and Sturgis Road.
The contamination raises additional concerns because the storm channels that drain the area, which is known as the Northeast Industrial Assessment District, feed into the Revlon Slough, which ultimately dumps into a habitat for endangered plant and bird species at the lagoon at Point Mugu.
However, a spokesman for environmental affairs at the Pacific Missile Test Center at Point Mugu, which oversees the estuary, said no signs of petroleum contamination have been detected there.
“That’s about 10 miles away, and there would be a great dilution factor,” said Ron Dow.
The contamination was discovered in late June by a Ventura engineering firm that contracted with the city to follow up on “hydrocarbon odors” that had been detected by engineers working in the area a year earlier.
“It smelled like putting gas in your car,” said Gerry Hels, project manager for Staal, Gardner & Dunne, a Ventura engineering firm that conducted tests in the area.
A preliminary test along the Sturgis Road and 5th Street storm drains revealed petroleum-related contamination in the soil at up to 60 times the levels allowed by state law.
Engineers conducting the test noted that the soil had been permeated with crude oil at depths up to 10 feet, and oil floated on top of ground water, raising concerns that it had also been tainted.
A more thorough test in July found that the contamination ranged in depth from 7 to 9 feet and extended 7,600 feet along pipelines that have been used to transport gas or oil from nearby oil wells and refineries.
The area has been an oil field for 30 years and still serves as home to the Oxnard Refinery, numerous oil storage tanks and equipment from the defunct Sun Oil Vacca Tar Sands facility, where oil was extracted from sand, Hels said.
The test also found xylene, toluene and benzene--all known or suspected carcinogens. In one sample taken along Sturgis Road, “extremely elevated levels” were found, with some compounds measured at 1,000 times above the state limits, Wong said.
The ground water beneath the oil-tainted soils was also found to be contaminated, but only the levels of chromium, a metal, exceeded state limits. However, engineers said the contamination may have resulted from pesticide spraying on nearby bean, tomato and celery crops.
City officials plan to bill landowners in the Northeast Industrial Assessment District for the cleanup.
City officials said they have met twice with assessment district members, who they said did not express opposition to the plan.
A developer at Tuesday’s meeting admitted to being “very disappointed” about the finding, but said he favored the costly cleanup rather than risk further delay in drainage channel work that had already been stalled for three months because of the contamination.
“It doesn’t do any good to build a car and then not use it because the ignition switch suddenly becomes very expensive,” said developer Russell Goodman, president of Sammis Co., which owns land in the assessment district.