Latest study says TCE worse than thought

Conclusions could lead EPA to propose tougher regulations

The Environmental Protection Agency has released a new report concluding that TCE — trichloroethylene, a pollutant found in much of Mountain View's groundwater — is definitely a carcinogen, a finding which could lead the agency to propose tougher cleanup standards.

"Many people across the country are exposed to TCE in their air and their water under current standards that would not be allowable under these (potential) new standards," explained Lenny Siegel, director of the Center for Public Environmental Oversight, a Mountain View-based nonprofit that helps in cleanup efforts at Superfund sites around the country.

But EPA toxicologist Dan Stralka noted that the report only makes conclusions on TCE's toxicity, and that no new standards have been proposed yet.

The report in question is a "toxicological review" released in December by the EPA, marking the most voluminous study to date of the human health effects of TCE, a solvent left behind by early Silicon Valley electronic manufacturers.

Siegel points out that the report concludes, on page 995, that "TCE is carcinogenic to humans by all routes of exposure" without qualifying that with "probably" or "highly likely." Human health effects include kidney and liver cancer, lymphoma and various other reproductive, developmental and neurological effects, Stralka said in a presentation to the Moffett Field Restoration Advisory Board on Jan. 14.

For years now, the presence of trichloroethylene in the soil and groundwater has spurred Superfund cleanup efforts at Moffett Field and in a part of northeastern Mountain View called "the MEW" (an area bordered by Middlefield, Ellis and Whisman roads), among various other sites scattered around Mountain View and Silicon Valley.

EPA project manager Alana Lee acknowledged that the size and scope of those cleanup areas could widen if the EPA proposes lowering drinking water standards for TCE. Current maps are drawn according to the 5 parts per billion standard, although Mountain View residents get their drinking water from the Hetch Hetchy water system, rather than local water tables.

The recent EPA report does not explicitly propose new standards for drinking water. But it does propose new standards for indoor air levels of TCE vapors, expressed in ranges which allow environmental advocates to call for heightened cleanup efforts. For residential areas, indoor air standards could go from 1 microgram per cubic meter to a range between 0.24 and 0.96 micrograms per cubic meter. Standards for business could go from 5 micrograms per cubic meter to a range between 2.5 and 9.8 micrograms per cubic meter. The difference between the standards for homes and businesses is partly due to the effects TCE has on children, Stralka said.

The new standards are similar to those created by the EPA and abandoned by the Bush administration in 2001. Siegel said he had not done an analysis of whether any homes or businesses in Mountain View could be called unsafe if cleanup standards changed as proposed. The cost of new mitigations on indoor air pollution would likely fall on the polluter for "existing" buildings, he said.

The vapors can emanate from groundwater as deep as 25 feet underground and into buildings that lack slab foundations or vapor intrusion membranes.

Siegel believes that the toxicology review of TCE was quietly worked on under the Bush administration, but political pressures kept it from being released. He says EPA scientists were told they would lose their jobs if they pushed for increased cleanup standards, which are a financial burden to polluters, including the U.S. military.

There is reportedly an effort by NASA and Office of Management and Budget officials to delay the new standards by sending the toxicology review to the National Academy of Sciences. Meanwhile, EPA administrator Lisa Jackson has received a letter opposing any further delays and signed by 29 people representing communities exposed to TCE across the country including Mountain View resident Jane Horton, whose Whisman Road home was found to have unsafe levels of TCE.

"As the Government Accountability Office has repeatedly pointed out, delays 'can result in substantial harm to human health, safety and the environment,'" the letter states. "That is, we don't want our families and our communities to be guinea pigs in permanent research experiment."

The TCE toxicology review and other updates on the subject can be found on the EPA's Web site here. Public comments on the recent review are due by Feb. 1.

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3 people like this
Posted by Steve Schramm
a resident of Sylvan Park
on Jan 29, 2010 at 3:57 pm

Interesting that the hetch hetchy aqueduct goes right through the area with TCE vapors. The article says the vapors can rise from 25 feet below ground to pollute the air. Is the aqueduct sealed? Is there a chance of contamination of our drinking water?

3 people like this
Posted by DSoldIt
a resident of Old Mountain View
on Jan 29, 2010 at 6:00 pm

I am hopeful that the city will take this study very seriously and reflect on how that last study affected housing prices in the Whisman Station neighborhood.

3 people like this
Posted by James
a resident of Whisman Station
on Jan 29, 2010 at 8:33 pm

From past sampling by the EPA the air around here (Whisman) is mostly below 0.17 microgram per cubic meter. I believe they did some more remediation since those measurments by pumping oxidizer into the ground water.

3 people like this
Posted by Jane B
a resident of Cuernavaca
on Feb 3, 2010 at 1:16 am

I cannot beleive anyone would want to live on toxic waste site? We should all pitch in and have all the Whisman Station residents move to India. Now!

3 people like this
Posted by Mary Blakely
a resident of another community
on Feb 5, 2010 at 6:49 am

My name is Mary Blakely and I am the daughter of a retired Vietnam Veteran. While I was growing up ,my family was stationed on Bases all around the world.The only place we ever lived more than once was in North Carolina on a Marine Corps Base called Camp Lejeune. In September of 2009 I learned from a CNN news story about a cluster of Male Breast cancer survivors that only had living on Camp Lejeune and the drinking water in common. At the time of the story there were only around 20 of them now there are 55 males involved that are known of. While the men were speaking about the the neighborhoods that were involved, they mentioned Berkley Manor. My family had lived on that part of the base in 1967-1969 when I was around 3 1/2 years old and we were stationed there again in 1976 when I was 13. My father retired in 1978 and still lives in a house that my mom and he bought just outside the front gates in Jacksonville N.C.,so even after retiring we were constantly on that Base. I started trying to find information about Camp Lejeune and contaminated water.Since then I have learned that the ground water that was the source for the drinking water for the base was contaminated with over 70 toxic chemicals from 1957-1987.One of the most prevalent toxins was TCE.In 1996 my Mother died of one of the signature cancers that TCE can cause. The rest of my family suffers from numerous ailments that I believe are a direct result of the chemicals that we drank,bathed in,cooked with,and breathed.The DOD and the Navel Department have done and continue to do all they can to keep this tragedy from the victims of it and the from the American people.I am a member of a group called The Few The Proud The Forgotten that have been fighting for years to get to the truth of this matter and to inform all the Veterans and their families that were poisoned.Many Men,women,and children have already died from their exposure to the toxic soup,one of which is a little girl named "Janey Ensminger".Congressman Brad Miller introduced a Act on Feb.2,2010 called,"The Janey Ensminger Act", that if passed might give the Vets and their affected family's some much needed medical help. Please help us by contacting your House Representatives at and ask them to support this Bill. Senator Richard Burr and Sen.Kay Hagen of N.C. had a bill(S-1518) in the Veterans Affairs Committee that was tabled on 1/28/2010 by Committee Chairman Akaka, he replaced it with his own piece of crap bill that will place all of the surviving victims health care back in the hands of The Department of Defense,the very people who knowingly allowed the toxic water to be used and have spent well over 20 years covering it up.The ATSDR has been ordered by congress to do a health and mortality study,but the DOD has refused to fund it and are slowing any actions from proceeding.They are hoping that all or most of the victims will die or get so sick that they will shut up.I refuse to do so and I am hoping that You our fellow TCE victims from Mountain View will help our cause and tell your local and national News Sources of our plight!I will tell people I know of yours and maybe both of our wounded can help each other.God Bless and Semper FI!Mary Blakely

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