Toxic chemical found beneath Rocketdyne lab: Trichloroethylene; TCE

State agency reveals new danger

By Roberta Freeman April 11, 2003

Officials from the state Department of Toxic Substances and Control announced Thursday that trichloroethylene, a cancer-causing solvent used since the 1940s to flush out and clean rocket engines after each test, has saturated the ground water, soil and sandstone at the Boeing Rocketdyne Santa Susana Field Lab in Simi Valley.

Officials said in a press briefing the cancer-causing solvent seeped to depths ranging from 240 to 450 feet into the ground.

The discovery means another dangerous agent can be added to the list of radioactive and chemical contaminants found at the site.

Last year the U.S. Environmental Protection Agency identified TCE as being 60 times more toxic than previously thought, noting that vapors from the solvent can permeate up through the soil into homes and workplaces. Currently the acceptable level for the chemical in drinking water is 5 parts per billion, which EPA officials say is likely to be lowered in the future. Well testing by the Department of Toxic Substances and Control at the Rocketdyne site revealed concentrations of TCE at 10,000 ppb and higher.

Dan Stralka, an EPA toxicologist, said TCE had been identified as a suspected carcinogen, and, depending upon level of exposure -- ingestion in drinking water or fumes -- can cause cancer, impaired immune system, abnormal heartbeat and liver, lung and kidney damage. The health effects of TCE are under review by the Academy of Science, Stralka said, but it has been substantially upgraded as a toxic substance.

"Now there are a lot more areas that provide a level of concern," Stralka said.

Gerard Abrams, Department of Toxic Substances and Control geologist, said cleanup of the chemical at Santa Susana will prove problematic because TCE is not water-soluble and has permeated into the sandstone bedrock of the site.

He estimated that a half-million gallons of the solvent had moved into the subsurface of the property.

"It moves through fracture spaces and into the sandstone pores, like water in a sponge," Abrams said.

Boeing spokeswoman Blythe Jameson said the aerospace company stopped using TCE to clean engines in the mid-1980s and now uses a nitrogen process that generates no waste.

"We are aware of the problem and have been pumping and treating the water," Jameson said.

But traditional water treatments are not effective for the most part in removing TCE from porous items such as sandstone, Abrams said.

"It has not been successfully cleaned up at a site that I am aware of," Abrams said.

A plume of contamination, he said, is migrating off the Rocketdyne site into Sage Ranch, a massive open-space area owned by the Santa Monica Mountains Conservancy south of Corriganville and Black Canyon in Simi Valley, which also includes an area for overnight camping. Abrams said further testing is ongoing to determine if TCE is migrating from the site in other directions.

Testing is expected to take another two years, Department of Toxic Substances and Control officials said. That testing will include a full environmental impact report of the Field Lab site. The agency's studies will exclude a portion of the property operated by the Department of Energy that contains radioactive contamination from nuclear testing and an accident in the 1950s.

Department of Toxic Substances and Control spokesman Ron Baker said a deed restriction might ultimately be put on the property to prevent homes from being built on the site if the agency determines that the TCE can't be cleaned up properly.

Members of a citizen oversight committee concerned with cleanup of the site said the TCE findings are alarming, coupled with concerns about radioactive and other chemical contamination such as perchlorate at the site.

"The extent of the new TCE findings are extraordinarily troubling," said Dan Hirsch, chairman of the oversight committee.

The new findings, "coupled with the EPA's new study that TCE can migrate up into buildings and expose occupants, raises serious questions whether the site will ever be cleaned up," Hirsch said.

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