FIELD LAB RADIATION TESTS INVALID, CRITICS SAY.

Byline: Kerry Cavanaugh Staff Writer

Environmental watchdogs said Monday that 15 years of water-quality testing at the Santa Susana Field Lab should be thrown out because the samples were filtered before being tested for radioactivity.

Activists have long warned that the Boeing Company's use of filtered samples produced artificially low radiation readings because they were only catching contaminants that made it through a microscopic filter.

Their concerns were backed up last week by a U.S. Environmental Protection Agency senior radiation scientist who said examiners have to look at the water and the material left on the filter to get a true picture of the radioactivity.

``You have to filter the water to make sure you can run the test, but then you have to test the filter. You have to do both things,'' said Gregg Dempsey, who heads the EPA's Radiological Emergency Response Team.

Without testing both the water and the filter, he said, ``It could skew it quite a bit.''

Prompted by Dempsey's comments, environmental activists called for a whole new testing policy at Boeing's field lab, including independent sampling.

``There's 15 years worth of reports and data, and the results are false because they used the wrong methodology,'' said Mary Weisbrock, who has been following the field lab cleanup. ``We know that filtering is lowering the results.''

Los Angeles Regional Water Quality Control Board officials said that, because of community concerns, they have begun a new study to compare filtered and unfiltered samples.

Under the new study ordered by the water board, Boeing must test filtered surface water and test the filtered sediment over the next 10 rains. The study should clarify whether more radiation is leaving the site than previously thought.

``If you're looking at the total environment, you want to look at the filter,'' said John Bishop, director of the water board.

Boeing officials said Monday that they followed state and federal testing protocols, but added they would comply with the water board's request to test the sediment.

``The procedure requires them to filter so they are just looking at the water,'' said Paul Costa, Boeing director of environmental protection. ``The EPA guidance is to look just at the groundwater, not the sediment.''

Company scientists filter some surface-water samples that have a lot of sediment, but they've never found radioactive contaminants above the drinking-water limits in filtered or unfiltered samples, Costa said.

In the past, water regulators looked at the surface water leaving the field lab, not the sediment or soil in the storm water.

Kerry Cavanaugh, [phone]

kerry.cavanaugh(at)dailynews.com

TO LEARN MORE

--The Department of Energy and Boeing will hold a public meeting tonight in Simi Valley to discuss additional environmental tests planned at the field lab before the cleanup is complete. The meeting will begin at 6:30 p.m. at the Grand Vista Hotel, 999 Enchanted Way. More information is available at http://apps.em.doe.gov/etec

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