Filters Skew Tests at Field Lab, Critics Say

Critics of the cleanup of Rocketdyne’s Santa Susana Field Lab near Simi Valley say water samples being taken to determine radioactivity and other contamination are being filtered before testing -- skewing the results.

U.S. Sen. Barbara Boxer (D-Calif.) wrote last week to federal Secretary of Energy Samuel Bodman criticizing his agency’s cleanup methods.

“In the scientific community, there is also concern that the testing at Rocketdyne has been inadequate, and in some cases, incorrect,” Boxer wrote. The field lab “sits in the middle of a suburban setting with homes, schools and businesses in close proximity. It must be cleaned up to safe levels.”

For decades until the 1980s, the lab was used to test rocket engines and conduct nuclear testing on behalf of the federal government. Research continued despite a number of spills and accidents, including a partial fuel meltdown in 1959.

At issue is the lab’s method for testing groundwater and runoff at the 2,800-acre hilltop site between Simi Valley and Chatsworth.

The water samples are first allowed to sit -- to separate mud and rock -- and then filters are used to strain out other impurities before testing. The results, critics say, show lower levels of radiation than unfiltered samples.

Daniel Hirsch, a nuclear policy specialist and member of an interagency work group monitoring the cleanup, said the danger of contamination could be 10 to 15 times greater than revealed by filtered water.

“The community is concerned that they’re throwing away much of the radioactivity,” Hirsch said.

Environmental activist Mary Wiesbrock, who attended the work group’s quarterly meeting last week, said the water test results can’t be trusted because of the method of measurement.

“They’ve done incomplete testing, so all the results are false,” she said. “And this has gone on for 15 years. When you consider public health and safety, it’s outrageous.”

But officials at Boeing Co., parent company of Rocketdyne, said state regulation requires them to use filters when testing groundwater and that the company filtered rainwater runoff only from February 2001 to November 2003 to ensure that testing equipment could detect the lowest levels of radiation.

Steve Lafflam, Rocketdyne’s director for safety, health and environmental affairs, said it’s “sort of a red herring whether it’s filtered or unfiltered, because it’s all met government standards. We haven’t exceeded any public health goals. People should be assured that the water meets all standards to protect public health and the environment.”

To determine the significance of variation between the two test methods, Lafflam said the Regional Water Quality Control Board has instructed Rocketdyne to gather samples of runoff during the next six storms. The water will be sent to an EPA-certified test lab, which will measure radioactivity using filtered and unfiltered samples.

Gregg Dempsey, a senior radiation scientist with the Environmental Protection Agency in Las Vegas, said that although filtering may be necessary when water has too much mud or other impurities, an unfiltered sample is preferable.

“It’s not a good way to run water samples,” Dempsey said last week about filtered samples. “We would call it a biased sample. It’s no longer representative of the environment.”

To accurately determine the level of radioactivity, he said, the test should take readings of the water, of the filter itself and of captured sediment.

The Department of Energy has scheduled a community meeting Tuesday to discuss the progress of the site cleanup effort overseen by Boeing. The session, at Grand Vista Hotel, 999 Enchanted Way, Simi Valley, will begin at 6:30 p.m. with an open house, followed by a presentation and discussion at 7:15.