Updated: Mon, Oct 10, 2011, 7:58 am
Uploaded: Fri, Oct 7, 2011, 3:14 pm
TCE causes cancer, other health woes, EPA says
Toxic chemical contaminates groundwater in Palo Alto and Mountain View
Despite political pressures to kill it, a long-delayed Environmental Protection Agency report has finally been released confirming the toxicity of the industrial solvent that has contaminated groundwater at a central Palo Alto Superfund site as well as in Mountain View.
The EPA's Final Health Assessment for trichloroethylene (TCE) characterizes the solvent, which was detected at the "Hewlett-Packard 620-640 Page Mill Road Superfund Site," as "carcinogenic to humans by all routes of exposure" and says that inhalation can cause "hepatic, renal, neurological, immunological, reproductive, and developmental effects."
Locals in Mountain View have paid particular attention to the EPA's findings on TCE, which was dumped into the ground by computer component manufacturers near North Whisman Road in the 1970s.
A link long has been suspected between TCE exposure and a cluster of seniors with Parkinson's disease and brain tumors on and around Walker Drive near Whisman Road. The Mountain View Voice reported in 2002 that six residents were found with Parkinson's on Walker Drive and four others were found nearby who had had brain tumors. They had all lived for decades next to an area that may have provided a steady supply of TCE vapors -- vapors that continue to be measurable in the outdoor air.
Activist and Whisman Road resident Jane Horton said the report's release was a small victory for the Walker Drive residents and many others who have been exposed to TCE nationwide.
"We can now say, 'Yes, this is a bad chemical and yes, it is proven,'" said Horton. "The fact this even happened, especially in this political climate, is a cause for celebration."
Some suspect that an air stripper used for years to treat TCE contaminated groundwater on the east side of Whisman Road near Walker Drive was partly to blame for the cases of Parkinson's, a degenerative disease affecting the central nervous system. Like a smokestack, the air stripper vented TCE to the atmosphere as contaminated groundwater was pumped to the surface.
"Everyone seems to think that there is something strange about this, everyone is concerned, especially the people who have Parkinson's," said resident Lori Hand in 2002. Hand said three had died and two others were in their 70s at the time. She said they had all lived there for over 40 years.
No evidence was found to make a link with the Parkinson's cluster. The air was never tested inside the homes of those with Parkinson's and Horton said the outdoor air wasn't tested until the air stripper was replaced with special filters that contained the vapors.
It was suspected that the TCE vapors, which have a half life of several days, were blowing into people's homes. "It's when it gets trapped in your home that it becomes a problem," Horton said.
Horton has some experience with that problem. Her Whisman Road home, which she purchased in 1975, was the only one in the area found to contain unacceptable levels of TCE vapors. The vapors were entering her basement from the large contaminated groundwater plume that computer component manufacturers left behind. A ventilation system now runs at all hours to keep the vapors out of the house, even in power outages, and her air is tested twice a year.
TCE vapors can still be measured in the outdoor air. Lenny Siegel, director of the Center for Public Environmental Oversight, said it was at 0.2 micrograms per cubic meter last time he checked, which is well below EPA's standards for indoor air. It wasn't uncommon for it to be well over 1 microgram per cubic meter at such sites when TCE was in use, which is above current standards for indoor air.
The EPA says 761 superfund sites are contaminated with TCE nationwide. People have died "horrible deaths" from their exposure to TCE in other places, Horton said. When she testified about TCE to the National Academy of Sciences, Horton recalled several "heartbreaking stories", including one form a brother and sister who carried their father's ashes. He was one of many workers of a Mattel toy factory in Oregon who died after exposure to high levels of TCE.
"This has really been long and lonely battle for individuals all throughout the country," Horton said.
The EPA's final health assessment for TCE is expected to accelerate cleanup efforts and make cleanup standards for indoor air and drinking water more stringent, especially in other states. By all accounts, the EPA's local cleanup standards are already relatively stringent and may not change much. But local activists say they are still frustrated by the slow pace of cleanup in the Whisman Road area.
Posted by resident,
a resident of Adobe-Meadows
on Oct 8, 2011 at 6:20 am
Trichloroethene (TCE), the chemical compound known to cause birth defects and cancer in lab animals, continues to contaminate groundwater in the California-Olive-Emerson neighborhood near California Avenue in Palo Alto, according to a report by Hewlett-Packard.
Based on a January HP quarterly TCE report, the Barron Park Association Foundation (BPAF), a nonprofit organization charged with monitoring TCE cleanup, identified several residential and commercial mixed-use properties that have soil-gas levels far higher than legally acceptable levels.
Namely, properties at 195 Page Mill Rd., 200 and 345 Sheridan Ave., and Birch Plaza are at risk, say foundation board members. "Most at risk is 200 Sheridan, where the two-level underground garage penetrates the aquifers, and the lower garage level periodically has contaminated ground-water leak inside," board member Bob Moss said. Moss is also a columnist for Palo Alto Patch.
The property at 200 Sheridan Ave. houses offices on the ground floor, a popular Italian restaurant called Caffe Riace and residential units on the upper floors. The owner of the building, Harold Hoback, said the building periodically had leakage in the garage during the last rainy season, Moss said. If the TCE-contaminated water has leaked into the garage, the toxins will evaporate into the air and can go into living spaces and expose people, Moss said.
Within the past year, Hewlett-Packard has tested 195 Page Mill Rd. for soil-gas levels of TCE, according to BPAF. Tests showed levels of "23,000, 25,000 and 150,000 micrograms/liter, far higher than any acceptable level for potential TCE exposure," stated a March BPAF letter to the San Francisco Bay Regional Water Quality Control Board. Environmental Protection Agency soil-gas action levels are 500 micrograms/liter for residential and 1,000 for commercial, according to Moss. This standard applies to Palo Alto; however, the water board has not enforced the levels, according to BPAF.
At 365 Sheridan Ave., the residential building "has an enclosed underground garage that is highly likely to experience vapor intrusion from both the aquifer and soils," BPAF wrote in a letter to the regional water quality control board.
BPAF has pestered the water board to perform official testing on contaminated buildings. The water board has had oversight for cleanup of underground-water contamination from the Hewlett-Packard 620-640 Page Mill Rd. Superfund site since 1991. Hewlett-Packard first found TCE leakage in 1981 from this site, said BPAF board president David Chalton. The company, which used TCE to clean electronics, occupied the premises during the 1960s, '70s and '80s. Leakage could have at any time during those years, Chalton said.
The water board has to do official testing in order to force Hewlett-Packard to clean up the mess, Chalton said. Yet the board has done nothing new to address increased levels of TCE in the groundwater, Chalton said. To date, it still has not done any testing on the identified buildings, said Chalton.
In the past, Hewlett-Packard has cooperated with other areas of cleanup, but "they don't want to spend the money unless required," Chalton said. "That's why we want the water board to do testing to see if TCE is really a problem or not. The water board has been reluctant to do that, and we have been trying to get the EPA to put pressure on it," he said.
"We've been fighting them for eight years to do indoor sampling and to require new buildings to have proper vapor barriers to prevent soil gas from getting into buildings," Moss said. "Basically, I've given up on the water board."
The city of Palo Alto must enact a law requiring developers to put in vapor barriers, Moss said. Palo Alto has not done anything because the water board has not recommended such barriers, he said.
Mountain View has had a city ordinance since 1993 requiring newly constructed buildings to have vapor barriers to prevent TCE gas from entering living and working spaces, Moss said. The EPA has aggressively cleaned up much of the contamination across 101 freeway from Moffett Field, he added. Nothing of the sort has happened in Palo Alto, he said.
"We already know the soil-gas levels at the Birch Plaza site are 6,400 micrograms/liter, which exceed action levels of 500 for residential and 1,000 for commercial," Moss said. "The Birch Plaza project still has no requirement for vapor barriers or indoor air monitoring." Last November, the City Council approved construction plans for Birch Plaza, at 305 Grant Ave.
"We're fed up with it," Moss said.
Cleaning up the mess requires a long process of pumping contaminated water out of the ground and filtering it, Chalton said. Palo Alto uses an outdated 20-year old pump-and-treat system, which is inadequate and has caused TCE buildup in some wells, according to Moss.
The "existing pump and treat system seems to have reached saturation in VOC removal" and "apparently will not reduce the levels of TCE to acceptable levels just by pump and treat," stated a BPAF letter to the water board. The BPAF has recommended a few alternatives to pumping, such as oxidation treatment and abiotic/biotic treatment.
Using the current pump-and-treat system would take 100 years to fully remove, the EPA and U.S. Navy has said, according to Moss. To date, however, neither the EPA nor the water board have done anything new to address ongoing high levels of TCE contamination in Palo Alto.
If you were a member and logged in you could track comments from this story.