The homes are a stone's throw from one of Silicon Valley's largest collection of toxic sites, an area once home to early silicon computer chip manufactures such as Fairchild and Intel, which used TCE as a solvent in their manufacturing process during the 1960s and 1970s. The plume left behind was first discovered in 1981. The area is now home to Google and Symantec, among others. Those buildings now have ventilation systems running at all hours to keep the underground toxic vapors at bay. The collection of Superfund sites is known as the "MEW" because it is bordered by Middlefield Road, Ellis Street Whisman Road and Highway 101.
The discovery of high levels of TCE on Evandale Avenue was a bit of a surprise to Lenny Siegel, director of the Center for Public Environmental Oversight in Mountain View. "We've been following the site for 30 years and we all the sudden find new concentrations in a residential area," he said.
Previous testing nearby had not found the underground plume migrating west of Whisman Road.
"There are a lot of people who should be concerned," Siegel said. "But a lot of the homes sampled turned out to be OK."
Information about the health effects of TCE isn't in the flier the EPA is giving to residents, even though in 2011 the EPA issued its Final Health Assessment for TCE, calling it "carcinogenic to humans by all routes of exposure" and that inhalation can cause "hepatic, renal, neurological, immunological, reproductive, and developmental effects."
Probes placed under the street on Evandale Avenue have found unusually high TCE groundwater concentrations, as high as 130,000 parts per billion of TCE near Pepperwood Court. The EPA's cleanup goal is 5 parts per billion. Those results were used to create a map of a "priority testing area" which contains about 30 homes, Lee said. A flier with a map was delivered to homes on the street with a request that residents get in touch with the EPA.
Despite the outreach effort, three residents within the priority testing area area told the Voice they were unaware of the situation on Monday or did not know whom to contact.
"We are really concerned and we want to know who to call," said Alicia Balmonte, a resident of the apartment complex at 190 Evandale Avenue since the 1970s. She said it would be nice to find out if there is TCE in the apartment "because my daughter is pregnant."
Link to cancer
While it is nearly impossible to prove that exposure to TCE pollution caused someone's cancer, several longtime residents are left to wonder.
Balmonte said she was diagnosed with cancer of the lymph nodes in 2004, which was successfully treated. She said it was different from non-Hodgkin lymphoma, which also attacks the lymph nodes and is linked to TCE exposure.
The Bay Area Cancer Registry recently studied historical data and found nearly twice the regional average rate of non-Hodgkin lymphoma in northeastern Mountain View between 1996 and 2005, but refused to release any detail that could show how many cases were found on a street like Evandale Avenue.
Across the street at 207 Evandale Avenue, Angelica Garcia wonders if there was a connection between her son's leukemia and the toxic plume. She said she had lived in her apartment — which sits in the priority testing area — for 12 years. Five years ago her son was diagnosed with leukemia when he was 4. "He's done with his treatment and he's fine. The cancer is in remission," she said.
Unaware of the danger
Another resident in the priority testing area on the south side of the street said he was entirely unaware of the issue. Ali shares a home with an infant, a high-schooler and two other adults. He told the Voice he was concerned "not for myself but for my baby sister, you know, more than anything else. If there is something serious I think we should be notified so if we should get out of here, we can get out of here. So many people have died in my family because of cancer it's a joke now. It's crazy."
He added that when he talked to the workers drilling into the street, "they said they were just testing the water and that's it." They even placed a tank inside his home — apparently testing the indoor air — without explanation," he said.
Garcia said she received similar treatment. She talked to workers but, "I don't recall them saying anything about any danger."
For its part, the EPA says its staff is knocking on doors to try and reach every resident.
"We have gone door-to-door in the impacted residential areas and tried to reach every resident in the impacted neighborhoods," said EPA press officer Rusty Harris-Bishop in an email, adding that fact sheets, access agreements and sampling results are provided in Spanish "where needed."
A transforming street
Evandale Avenue is a mix of apartments, duplexes, condos and townhomes. It is home to some of the area's poorest residents, but is also to a growing number of tech employees as Google moves in nearby on Whisman Road. Despite being located near the priority testing area, one condo dweller was happy to report that his neighbor had put his three-bedroom unit up for sale a few weeks ago and in three days 300 possible buyers walked through. "It was pretty astonishing. Some large fraction of them must have been Google employees."
The drive for housing in the area spurred an investor to renovate a former slum at the corner of Evandale Avenue and Whisman Road. The EPA's Lee said the owner of the 64-unit complex refused to allow testing of the units, formerly known as 291 Evandale Avenue, now known as 600 Whsiman Road. The crawl spaces under the units passed air tests before they were renovated, Lee said. Nevertheless, one resident of the complex said she would prefer to know for sure that her home was safe.
TCE pathway a mystery
Siegel said there is some suspicion that there is a pathway under the street allowing TCE to migrate from the MEW under Evandale Avenue. The EPA had tested on Devonshire and Fairchild Drive before, and had not found evidence of the plume migrating very far past Whisman Road. "Hopefully it is just gravel around the sewage line or something," Siegel said.
The latest discovery is proof that "to prevent intrusion (of vapors into homes) you need much denser sampling," Siegel said. "That's what we asked for and that's what we got."
The plume of TCE in the groundwater — which is not used as drinking water — slowly shifts overtime, mostly flowing towards the Bay. But more sampling of the groundwater would require permission from landowners. "It's harder to get permission to sink a probe into private property," Siegel said.
The EPA says it will continue to seek permission for such tests on private property.
Residents in the priority testing area are asked to contact the EPA for indoor air testing. The indoor air tests are voluntary and renters who want the tests need to get permission from their landlords. Lee said in some cases that was an obstacle, but the EPA was eventually able to get permission for the tenants.
If indoor air is above the limit, ventilation systems are installed at the expense of the polluters, but in a situation where a renter wants such a system, "The owner certainly has to agree," Lee said.
A meeting between the EPA and the Wagon Wheel Neighborhood Association is set for Sunday March 3. A time and location was not available by press time.
For more information, contact the EPA:
EPA Vapor Intrusion Project Manager
EPA Groundwater Project Manager
EPA Community Involvement Coordinator
This story contains 1409 words.
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