Search begins for Orion Park polluter Search begins for Orion Park polluter (September 23, 2005)

EPA officials expect to complete groundwater sampling this week

By Jon Wiener

Officials from the Environmental Protection Agency are trying to identify the source of a mysterious underground plume below a military housing complex just south of Highway 101 near Moffett Field.

The source of trichloroethylene contamination in Mountain View's groundwater at Orion Park has vexed everyone from NASA, who discovered the problem, to the Navy, the property owner, to the long-vanished manufacturing companies responsible for the nearby plume in the Middlefield-Ellis Whisman area.

"It's hard to guess what we're going to find," said Alana Lee, who is heading up the project for the EPA. Lee said the cost of the sampling effort, which began last week and should produce final results by the end of October, will run as high as $100,000 -- relatively little in the world of Superfund cleanups.

Lee and her staff have spent the last several months combing through every file and record that might provide some hint as to how the chemical solvent got there. They have searched aerial photos, city directories, water district permits and fire department records in hopes of finding some link to one or more polluters that might be held responsible for the cleanup.

Lee said there have been many potential culprits operating in the area in the past, including manufacturing companies and dry cleaners, two types of uses that frequently rely on TCE.

Simply identifying who would conduct the groundwater testing has been a bone of contention that delayed any potential cleanup at Orion Park for several years. The Navy still maintains that it does not have to conduct testing in Orion Park homes, which are now owned by the Army, because it is located outside the Moffett main gate. The Navy eventually relented after pressure from the public and other agencies, but clean-up officials backed out of an earlier plan to conduct groundwater testing off-site.

Though Hangar One gets most of the attention from those involved with the base cleanup, far more people may wind up getting exposed to unhealthy levels of TCE at Orion Park. Groundwater there is more contaminated and closer to the surface than at any other residential area where the EPA is overseeing clean-up efforts, The most recent Navy samples of military homes show that toxic vapors have come up through the ground and gathered in several of them.

E-mail Jon Wiener at jwiener@mv-voice.com

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