So far, the information about TCE distributed to residents by the EPA does not include the stark assessment made in 2011, which said the chemical is "carcinogenic to humans by all routes of exposure" and that inhalation can cause "hepatic, renal, neurological, immunological, reproductive and developmental effects."
Why has the EPA not publicized this clearly pertinent information in what the agency is calling "high priority areas for indoor air sampling?" It is a concern that off-the-chart concentrations of TCE have been found in test wells drilled into the street on Evandale Avenue and the agency should do more to push property owners to allow samples to be taken under homes, where residents could be breathing high concentrations of this dangerous chemical. So far only two homes were found with concentrations of vapors about the EPA's acceptable limit, but more testing needs to be done. The primary remedies suggested by the EPA are installing ventilation systems, sealing off areas around conduits or doing remedial work to lay material under the home that would stop the vapors from entering the building's living or working space.
Meanwhile, members of the Voice staff last week easily found a handful of Evandale residents who were not fully aware of the TCE threat to their homes despite the EPA's outreach efforts. They had no idea that probes placed under their street showed TCE groundwater concentrations as high as 130,000 parts per billion, an astronomical level when compared to the EPA's allowed limit of 5 parts per billion. One resident of an Evandale apartment complex said she did not know who to contact, and that she is concerned because her daughter is pregnant. Another resident of the priority testing area, who had lived in her home for 12 years, wondered if there was a connection between her son's leukemia, which he contracted five years ago when he was 4 years old, and the toxic chemical flowing under her home.
Like other chemicals known to cause cancer, it is impossible to definitively say that breathing TCE has a direct link to a particular cancer in someone. But a recent study by the Bay Area Cancer Registry found nearly twice the regional average rate of non-Hodgkin lymphoma in northeastern Mountain View between 1996 and 2005, although the registry refused again this week to say how many cases, if any, were found on Evandale Avenue.
Lenny Siegel, director of the Center for Environmental Oversight in Mountain View, was surprised by the migration of TCE to Evandale Avenue, a block or two west of the known locations of underground TCE plumes. He told the Voice: "We've been following the (MEW) site for 30 years and we all of a sudden find new concentrations in a residential area." Prior to this discovery, the chemical was thought to be contained in the MEW area, defined by its boundaries of Middlefield Road, Ellis Street and Whisman Road, which has been declared a Superfund cleanup site.
The EPA has admitted that it was slow to react to the unexpected discovery of TCE west of Whisman Road. And they have said area residents will be given more information about the hazards of the toxic gas. Residents are also invited to a public meeting March 3 where the EPA will answer questions about TCE.
After 30-plus years of tracking TCE in the MEW area, it is time for the EPA to be more proactive in protecting the health of residents who unwittingly find themselves in a home loaded with a dangerous, carcinogenic gas. Perhaps EPA officials should go door to door with testing kits and to make sure no one is living with high concentrations of the gas. The most recent measurements in the street of TCE concentration — in many cases well over 1,000 and in one case 130,000 parts per billion — are very concerning. If levels can be this high in the street, they could be very similar under nearby homes. The EPA is responsible for protecting Evandale residents from the harmful effects of TCE. We hope they can get the job done, and soon.