Skip to comments.Are Sewers Source of Toxic Hot Spots in Mountain View?
Posted on 02/17/2014 10:10:26 PM PST by nickcarraway
Are Sewers Source of Toxic Hot Spots in Mountain View? advertisement
The toxic chemical TCE has popped up in residential neighborhoods in Mountain View outside the boundary of an EPA Superfund site.
NBC Bay Area looked at maps of city infrastructure to follow the trail of toxic hot spots. The EPA is currently studying whether the sewer and storm drain system are serving as a conduit to transport the chemicals into neighborhoods.
The US Environmental Protection Agency says it wants to find out the source of so called rogue hot spots of the chemical TCE which have been measured in residential neighborhoods recently. TCE is known to be in a large plume of toxic chemicals that make up one of two Superfund sites in and around Moffett Air Field in Mountain View.
Last year, NBC Bay Area first reported that the new hot spots were discovered outside of the Moffett Air Field Superfund sites. Now, residents and environmentalists are theorizing that the TCE might be escaping the boundaries along underground sewer and storm drain lines.
EPA officials confirm that they are studying that theory.
The EPA is investigating the source of these TCE hot spot areas, said Alana Lee, the Superfund site project manager. Were working with the city of Mt. View and looking at historical information. At this time EPA has not drawn any conclusions.
Moffett Field Toxic Plume Concerns Along an idyllic trail in Mountain View, an environmental consulting firm and the EPA discovered concentrations of TCE in Stevens Creek in Mountain View. They concluded that it came from leaking sewer lines, said environmental activist Lenny Siegel. Siegel rides the trail regularly and believes that the evidence points to the storm drain and sewer lines themselves as part of the problem.
These are sewer lines that originate from the Superfund plume itself.
At the center of all this is the EPA Superfund project called the MEW, or Middlefield Ellis Whisman site. Its been around since the 1980s when the EPA first identified several toxic chemicals left in the soil and ground water from the budding semi-conductor industry that was based here.
The most prevalent chemical that lingers in the soil, ground water and the air here is Trichloroethylene or TCE. Its a toxic cleaning solvent once commonly used by industry and the military. Studies have shown it can cause cancer in people and heart deformities in unborn babies.
This map shows locations where high amounts of TCE has been detected in soil samples, along with storm water drainage routes that connect with the MEW Superfund site. Six years ago this month, Edgar Garcia developed acute lymphoma when he was three years-old.
It was a hard battle, said Angelica Garcia. We were in the hospital more than at home.
The Garcia family live just outside the boundary of the toxic plume in Mountain View.
The first time we heard he had cancer, we didnt believe it, said Garcia. I want to know if where we live has something to do with it.
Edgars cancer is in remission after four years of treatment. But just last year, high concentrations of TCE were measured in a house just across the street from where the Garcias live. The Garcias told us they contacted the Investigative Unit, because I wanted to know more answers and it see it would cause his cancer.
The Garcias are waiting on answers about the origins of Edgars cancer, but the Investigative Unit decided to dig further into TCE seems to be spreading.
We obtained a map of Mountain Views sewer and drain system from the city and aligned it with a map showing concentrations of TCE in neighborhoods outside of MEW. The hot spots easily line up with the sewer system.
Its enough of a relationship to raise questions about whether the underground network is spreading the contamination.
Further bolstering the theory: this report from an independent environmental study group. The report found high concentrations of TCE along this property outside the Superfund site boundary.
How Google Execs Get Flying Privileges at NASA Ames The report points to the storm drains and sewer lines that extend back into the Superfund site as a source of the contamination.
Its not proof beyond a reasonable doubt, cautioned Siegel at the Center for Public Environmental Oversight. But its the best explanation of the data. And its the best explanation we have right now is that these horizontal conduits, storm drains or sewer lines are the source.
In a meeting just last week, EPA Superfund site project manager Alana Lee said her team is still not sure why these hot spots have popped up outside the boundary area.
Were certainly investigating the potential of the sewer lines. But again, were looking at a lot of information, evaluating that data and at this time, were unable to draw any conclusions.
For the Garcias, their questions are even more basic: I think I would like to know if my son is actually, his cancer came from that, said Angelica Garcia. And why?
The EPA is still working on a plan to test the sewer line theory by look at air and groundwater samples in and around neighborhoods surrounding the superfund site. They say they hope to have a plan in the coming months.
The EPA stresses that drinking water in this area is not affected.
In the meantime, residents like the Garcia are left with lots of questions but few concrete answers.
Since they closed down and moved a lot of semiconductor manufacturing to other countries, there’s gotta be a lot of TCE residue ... not to mention other even more toxic residues ... in an around Silicon Valley.
Left overs from ic mfg during the 80s. They thought they could lock the plume. They didnt
I was intimately familiar with that project (MEW site) about 13 or so years ago. I saved the treatment system air stripper tower a load of grief by keeping a load of hydraulic oil from getting pumped into it from a freight elevator failure in a building that sent water to it.
It was, at that time, already becoming known that rising groundwater levels were occurring in the area due to the change from agricultural to industrial. It was already up 20 feet in some areas and in that building with the elevator, if you didn’t keep it pumped (it was like a giant extraction well in the basement) it would fill the elevator shaft, a half dozen 20+ thousand gallon sub basement sumps and come up about 2 feet on the basement floor.
Obviously it’s risen high enough that it’s made it into the sand/pea gravel bedding of some type of local utility lines.
That being said, TCE is a Dense Non Aqueous Phase Liquid, i.e. it’s heavier than water, and not very soluble in it at all, so they’re talking miniscule quantities here unless someone is dumping it or cleaning car parts en-masse in their driveway...
Actually, the chlorinated solvent plume sites are disappearing rapidly with the advent of substances like Hydrogen Releasing Compound. It enables bacteria to eat it rapidly. There are sites I worked on in the SV that had wells you needed to wear a respirator to open the lid on, and those sites are closed now.
I’m actually surprised to see that MEW is still chugging along this much, though that is probably in part due to contamination spanning 2 or 3 aquifers vertically. I know one consulting/remediation group that milked 74 million dollars out of that site over 14 or so years, IIRC...
TCE was also used as an industrial cleaner, solvent, and paint stripper, especially by the USAAF during World War II. That’s why so many Air Force bases and facilities are TCE superfund sites.
Nothing wrong with me that a new liver wouldn't fix ';^)