Though the complex sits outside a "high priority" testing area initially designated by the EPA, all five of the homes tested showed elevated levels of trichloroethylene vapors (TCE), including two on the Devonshire Avenue side of the complex, entirely outside of the area where the EPA is offering free, voluntary indoor air tests.
TCE is the cancer-causing solvent that computer chip manufacturers released or dumped in the ground for several decades at the nearby MEW Superfund site, where a cleanup began in the mid-1980s. The EPA only recently tested the groundwater on Evandale Avenue, finding TCE there in unprecedented levels for a residential neighborhood in Mountain View.
"If there's a cancer risk, I've got enough genetic risk; I don't need this helping me," said Kristen Purdum, who has lived in the complex along Evandale Avenue for three years, her husband 11. "Cancer runs in my family."
While Purdum is still waiting for the lab results for the air sample EPA contractors took three weeks ago, there were results within minutes of placing a length of Teflon tubing in her living room from the machine, which is mounted in a van.
The result drew a "wow" from Lenny Siegel, director of the Center for Public Environmental Oversight, a watchdog of local cleanup efforts for 30 years that organized the demonstration.
"That's the best TCE hit I've ever seen," said Todd Rogers, assistant professor of chemistry at Columbia Basin College, looking at a WiFi-equipped tablet computer in his hand. He has been overseeing the company's initial tests while collecting data for research. "That's a graph that will probably end up in a publication," he said, pointing to a graph of TCE vapor levels measured every 30 seconds.
The preliminary results showed 8 micrograms per cubic meter in Purdum's living room and 11 upstairs, where the bedrooms are — well above EPA limits of 1 microgram per cubic meter for homes. The highest levels found on the street late last year was 18 micrograms per cubic meter.
Rogers said he was "confident" in the results, but wanted to do some more analysis to confirm the numbers since it was the first time the team had used the machine inside homes. Air samples were also collected in canisters to be analyzed in lab to provide more confirmation.
In the nearby "high priority" area for indoor air testing, 30 homes were tested and only two were found with elevated levels. It seemed to make sense to Purdum that she had the highest levels of the units tested in the complex. "Well, I'm closer to the hot spot," she said, referring to an area on Evandale Avenue near Pepperwood Court, where extremely high levels of TCE were found under the street. "I'd rather know than not know."
She looked at the apartment complex next door at 207 Evandale Avenue, and said, "If I were living in those apartments I would definitely want to know."
Siegel gave Purdum some advice, saying "the first thing you can do is keep your windows open."
That proved true in another unit in the complex with a Devonshire Avenue address. It was discovered that the windows had been open when testing found levels below EPA's limit, around a half a microgram. The tube was then placed in a closet, where the vapors hadn't had a chance to dissipate, and the result showed 2.5 micrograms per cubic meter.
"The lesson for those who do have contamination, is open your widows until you have mitigation," Siegel said.
Next door to Purdum, Helen Tsao's home had also shown elevated levels, though only about 1.2 micrograms per cubic meter — slightly above the EPA action level. Siegel said it was evidence that homes on the same foundation slab could have entirely different results if a crack in the foundation was funneling the vapors into certain areas.
Tsao said she wanted the test done partly because she wanted to know if there would be a risk if she were to have children someday. The amount of TCE vapor that could trigger heart defects in unborn children is 2 micrograms per cubic meter when exposed at all hours of the day, 24 hours a day, seven days week, according to the EPA's Final Health Assessment for TCE, issued in 2011.
EPA indoor air project manager Alana Lee arrived amidst the testing to talk to residents and ask questions about the methods being used. Rogers was preparing to present the results to EPA officials in San Francisco the following day.
"If they are finding something, I do want to confirm it with our own testing," Lee said.
Perhaps the most surprising results were in the two homes closer to Devonshire Avenue, one of which had results of 5 micrograms per cubic meter. "EPA did not sample these units because they thought it was too far from the plume," Siegel said.
Another home, on the second row back from Evandale Avenue, had levels over 3 micrograms per cubic meter.
Levels were also slightly higher upstairs in all of the five units -- where the bedrooms are -- which was a surprise. "That's not what I would expect," Rogers said, explaining that TCE vapors are heavier than air.
Siegel said research has shown TCE vapors are drawn into homes when they are heated in the winter because the pressure is lower inside than outside, and that the effect is more dramatic the higher the temperature difference is. Bathroom fans and gas-powered appliances can have the same effect of creating lower pressures indoors.
There is some debate as to whether the new technology is more accurate than the EPA's methods of collecting an air sample in a vacuum canister over several days. EPA spokesperson David Yogi stressed that the EPA-backed methods have been proven and vetted, and any new technology or contractor would also have to be vetted before they could be funded by the EPA. Rogers said the technology was still "years away" from being used widely. R.J. Lee is negotiating with large companies and government agencies to use it for indoor air testing.
The EPA's Lee said she couldn't yet comment as to whether the results at the Devonshire addresses would trigger the expansion of the area in which the EPA is offering free indoor air testing.
"They should offer it to the entire complex" Siegel said. "The general rule of thumb is that the TCE vapors can travel 100 feet in any direction."
Michelle Le contributed to this report.
This story contains 1162 words.
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