By Chris Bowman, Sacramento Bee
Construction in the fast-developing foothills of El Dorado County has been unearthing and stirring up naturally occurring asbestos, creating a potential cancer hazard to some residents – especially children.
The threat is largely unknown to county officials and the many families who moved to the golden hills in pursuit of a cleaner environment.
Tests commissioned by The Bee confirmed the presence of a particularly hazardous kind of asbestos in neighborhoods of El Dorado Hills and Latrobe. The fibers were small enough to reach deep into the lung, yet large enough to lodge there for life and cause cancer.
Microscopic and X-ray analysis found these amphibole fibers, along with the more prevalent chrysotile asbestos, in the serpentine bedrock that pervades the area.
High concentrations of these fibers were found in the settled dust inside three homes.
And dust raised by traffic on an unpaved road in residential Latrobe measured 22 times the federal limit on asbestos exposure in schools.
All sampling was near asbestos veins left exposed on road embankments.
Six authorities on asbestos-related diseases who reviewed The Bee‘s test results found them worthy of further investigation. One of them – Marc Schenker at the University of California, Davis, School of Medicine – promptly submitted a research grant proposal for a statewide study on the possible connection between cancer and natural asbestos deposits.
Though too limited to suggest an imminent health threat, the findings should prompt officials to minimize the disturbance, said the reviewers – all environmental health researchers at North American universities.
“It is believable,” said Arthur Langer, a City University of New York scientist who helped uncover a major cancer cluster in Metsovo, Greece, due to the same amphibole asbestos found in El Dorado County, although at higher levels. “You’ve got the material, the material is disseminated. You don’t know the extent of it. But it says there are instances out there in which this is a real problem. It should be looked at.”
Many El Dorado County residents probably face no asbestos hazard as they live well away from the serpentine that hosts the fibrous mineral, said UCD geologists Howard Day and Robert Matthews, who toured the region at The Bee‘s request. But thousands of others may be affected as they live in areas where the greenish rock has been disturbed, they said, and developments for thousands more residents are in the offing.
Potential exposure to airborne asbestos most likely goes beyond the newspaper’s test areas. Serpentine also runs through Cameron Park, Rescue, Shingle Springs, Pilot Hill and other parts of the county, geology maps show.
Officials in other serpentine regions, from the hills of eastern Virginia to the Coast Range of California, said asbestos exposure can be vastly reduced by requiring builders to monitor air pollution when they work and to cover exposed veins when they’re done.
Even the four-person air pollution staff in Lake County closely regulates building in serpentine.
Dennis Youngdahl, whose environmental consulting firm has done most of the geology investigations for developers of the 20-year-old El Dorado Hills community, vowed to set up a task force of engineers and geologists to propose a local ordinance controlling asbestos dust.
“That’s something that very easily could be done and probably should be addressed,” Youngdahl said, “especially now that you’ve done these studies on the houses, and found that (the asbestos) is being tracked inside.”
Youngdahl said he had not known building in serpentine could be hazardous. El Dorado County officials said they usually turn to veteran consulting geologist George Wheeldon for advice. Wheeldon, who has investigated many Mother Lode sites for developers, said air monitoring during construction would be impractical.
“If we are going to do that much of a constraint, we had better put a blanket over every serpentine outcropping in the whole state – not allow a water line to be cut or a road to be graded or any other kind of construction,” he said.
Locked in the Earth, asbestos poses no danger. But blasting, drilling, earth-moving and grading in serpentine can disperse the mineral fibers, especially on dry days, industrial hygienists said. The wind-blown specks can stay suspended for weeks, they said.
Asbestos can surpass safe breathing levels during construction without proper dust controls, officials with the state Occupational Health and Safety Administration said. Airborne amphibole asbestos of the kind found in California is a special problem, as spraying water is not sufficient to suppress it, they said. The airborne danger can linger for occupants of new homes. Fibers from uncovered veins are easily liberated by erosion, the hygienists said.
While all asbestos has been shown to cause cancer, most of the scientists who reviewed The Bee‘s findings expressed special concern over the presence of amphibole asbestos, specifically the tremolite and actinolite forms.
Most lung disease experts agree the needle-like amphibole fibers are significantly more potent than the curled chrysotile fibers in causing mesothelioma (mees-o-thee-lee-O-ma) – an inoperable and almost always fatal cancer of the membranes lining the chest and other body cavities
“Exposure to this amphibole asbestos would be a high-risk, high-hazard situation for particularly cancer and especially mesothelioma,” said Schenker, who wrote a widely used textbook on occupational and environmental lung disease.
Short exposure – months, not years – may be followed decades later by an onset of malignancy and death, disease experts said. That means children are especially at risk because of their long life expectancy.
“The risk increases with time from onset of exposure,” Langer said. “Your risk is seven times higher if you are born in the exposed area than if you moved in at age 30.” But scientists don’t know exactly how much asbestos someone must inhale to cause cancer.
Jim and Toni Johnson live near the Weber Creek quarry, which routinely crushes serpentine. They have been trying for two years to find out how much asbestos is in the air they breathe.
“All I would say is amphibole asbestos is not the material I would want to be the test case on,” Schenker said. “This, more than any other environmental agent, causes me great concern because of this untreatable cancer that it causes.”
County planning and environmental officials said they had no confirmation of amphibole asbestos in the region, and no reason to believe the public was exposed to unsafe levels of chrysotile.
“We are not requiring any projects that are going into (serpentine) areas to take any precautions or to avoid those areas,” said Conrad Montgomery, the county planning director.
Ron Duncan, the county’s director of environmental health and chief air pollution control officer, said he wants to see evidence of harm in the region before issuing advisories or investigating development’s asbestos pollution.
“I just haven’t heard that we really ought to be looking for a different thing besides chrysotile,” Duncan said.
Asbestos is subject to significant disturbance in western El Dorado County.
About 40 housing and commercial developments are currently proposed or are being built in serpentine areas of the county, Planning Director Montgomery said. In the past year alone, county supervisors have approved tentative maps or specific plans for 4,319 new homes in areas known to contain serpentine, planning officials said.
The county tracks this development because of federal protections for rare plants that grow in serpentine areas. No more than 3,500 acres is expected to be put off limits to builders for these protected plants, federal wildlife officials said. That leaves at least 36,000 developable acres of serpentine landscape, they said.
And more development is sure to come. Population is expected to double to about 225,000 in the next 20 years for western El Dorado County.
But the potential asbestos exposure is scarcely known or talked about in the county. The Bee found no mention of it in public planning records on any of six recently proposed or built housing tracts in serpentine rock land.
Two of the three families who opened their doors to the newspaper’s industrial hygienist said they had no idea their homes contained elevated levels of asbestos, much less that it originates from a native rock.
Each of the six samples taken from settled dust in the homes contained thousands of breathable asbestos fibers per square inch – indicating a nearby source of contamination, said Christopher J. Tennant, a state-certified asbestos inspector and a professionally certified industrial hygienist hired by The Bee. The houses were built after 1980, when asbestos had been phased out of home construction.
The asbestos probably was carried into the homes by wind or on people’s shoes and clothes, most likely from area veins uncovered in construction, Tennant said. Amphibole asbestos is especially prone to dispersion, mineralogists say. A piece of tremolite or actinolite the size of a matchstick separates easily between the fingers, whereas the same amount of chrysotile takes considerable flexing to break.
“Exposed tremolite-actinolite in road cuttings is eroding onto sidewalks and roads, increasing the potential of the mineral being broken down further into small enough fragments to become airborne and potentially respirable,” Tennant said in his report to The Bee, which was distributed to health experts and government officials earlier this year.
The families feared for their property values, if not their health. “I’m worried about my kids,” said Susan Beck, a 35-year-old San Jose native who moved to rural Latrobe for a life of “Little House on the Prairie.”
“It’s not a pretty thought that our dream house may be sitting on a piece of dynamite,” she said. “But we should know about it.”
The Becks’ home on Cothrin Ranch Road was one of three in the Latrobe and El Dorado Hills communities that The Bee tested on Sept. 6. All were near road embankments with exposed asbestos veins. Other homes in those neighborhoods were not tested.
There was no disturbance of serpentine earth apparent in the area at the time of the tests, Tennant said. Air samples around the homes showed no asbestos levels of health concern, he said. But scientists were concerned about the asbestos found in settled dust inside the homes because it indicated particles had been in the air indoors, where people spend most of their time.
Ron and Judy Bolander allowed Tennant in for a check of the living room in their 2-year-old El Dorado Hills home on Woedee Drive. The Bee informed them that a high-powered microscope picked up fibers of actinolite and chrysotile in dust collected atop a high shelf and the front door.
The Bolanders were disturbed by the news, but resigned to it. “There’s nothing I can do about it,” Judy Bolander
said. Further air sampling would be needed to tell whether the asbestos posed a health risk across the street at Oak Ridge High School and the El Dorado Hills Community Center on Harvard Way. Environmental consultant Youngdahl said a nearby site where Rolling Hills Middle School is being built contains no serpentine.
Terry Trent and Carol Adams were not surprised by the results of the inspection of their home on Wild Turkey Drive. Their concerns about asbestos contamination prompted The Bee‘s investigation. The analysis reinforced their consultants’ tests indicating hazardous contamination from an unusually large number of tremolite veins on their 10-acre Latrobe lot.
Trent and Adams recently gave up a two-year search for a solution and let the bank repossess their seven-bedroom home overlooking the Sacramento Valley. “Never did I think I would be put into a position where I couldn’t protect my family,” Trent said.
Government rule books are thick with protections for employees who work around asbestos and for children in old school buildings containing the stuff in floor and ceiling tiles.
In El Dorado County, the knowledge and safeguards surrounding dispersion of naturally occurring asbestos are scant by comparison. Consultants who have investigated foothill development sites said the heightened mesothelioma risk posed by amphibole asbestos would be news to most geologists.
The state Division of Mines and Geology’s guidelines followed by developers’ consultants do not address serpentine. State Geologist James F. Davis said he would investigate whether revisions are warranted.
Neither county rules, nor state and federal regulations protect the public from exposure to naturally occurring asbestos arising from construction.
El Dorado is the worst county in the state when it comes to policing environmental rules on serpentine quarries and other mines, state mining regulators said. Lou Green, the county’s chief attorney, said that any problems are in the past. “We are on top of it now and we are performing our enforcement responsibilities as lead agency,” he said.
All five members of the county Board of Supervisors said the county should address the issue immediately.
Supervisor Walt Shultz of Cool expressed concern over setting off “a flurry of fear” that could stymie development. And Sam Bradley, who represents El Dorado Hills, Latrobe and part of Cameron Park, believes adopting asbestos protections for development would be a tough political battle.
“There would be people upset with me for even raising the issue,” Bradley said. One law on the books that might be expected to protect people from natural asbestos has been no apparent help to Jim and Toni Johnson.
The Johnsons live within a stone’s throw of the Weber Creek quarry along Lotus Road, which routinely crushes serpentine. They have been trying for two years to find out how much asbestos is in the air they breathe.
Toni Johnson said the quarry sometimes creates such dust that “you cannot see our house from the end of the driveway.”
The quarry is supposed to follow a state air pollution law that requires regular sampling of serpentine gravel for roadways and other surfaces to ensure the asbestos content does not exceed 5 percent.
Yet a lawsuit filed in September by the state Department of Conservation alleged that the county knew of quarry owner Loring Brunius’ “failure to perform required sampling,” and that the county had not adequately addressed his “consistent failure to control dust.”
The suit charged that Brunius’ plan to ensure long-term environmental protection was inadequate, and that the county had violated state law by approving it.
Brunius insisted that the state’s allegations are incorrect. He said he complies with the testing rule and that dust clouds from his operation are infrequent. “Unfortunately, there’s a lot more hysteria than fact,” he said.
County Counsel Green said: “The board maintains that the plan is adequate and complies with the law, but we’re still willing to sit down with the state and see if we can reach an agreement.”
It may be hard to see danger in something as natural to the foothills as oak trees. The serpentine outcrops are recognizable enough, with their waxy luster and many shades of green and blue. Many foothill residents cover their driveways with serpentine gravel. Some frame their yards or fireplaces with the decorative rock.
But it was something else that moved the state Legislature in 1965 to anoint serpentine the official “state rock.” The California Federation of Mineralogical Societies made the pitch: “It is the host rock for the state’s newest and most rapidly growing mineral industry: Asbestos, now bringing in several million dollars annually.”
At the time, health hazards of asbestos fibers were becoming widely apparent in industries that used the mineral for heating insulation and fireproofing.
In California, official awareness of the threat posed by naturally occurring asbestos did not surface for another 20 years. It has centered on the thousands of miles of roads covered with serpentine gravel.
In 1986, concerns from Calaveras County residents prompted the federal EPA to blacktop 50 miles of roads to encapsulate asbestos fibers that were being released when cars crunched the gravel. The agency warned parents living along serpentine roads: “Teach your children to avoid walking or riding their bikes behind moving vehicles.”
Later that year, a federal clean-up team descended upon El Dorado County northeast of Coloma. Crews wearing respirators paved a road in Garden Valley Ranch Estates whose serpentine gravel contained up to 20 percent chrysotile. The U.S. Environmental Protection Agency considers stone exceeding 1 percent asbestos unsafe for roadways. It wasn’t until spring 1996 that amphibole asbestos came to the attention of county officials, when Trent fought a neighbor’s plan to blast through asbestos veins.
Wheeldon, the consulting geologist for area developers, couldn’t recall finding amphibole asbestos in his more than 20 years of site investigations.
“If this is such a problem, shouldn’t there be an abnormally high incidence of lung cancer and mesothelioma . . . for people who live specifically in the Mother Lode?” he asked.
Scientists say it’s too early to tell for El Dorado County.
Mesothelioma, which is almost always linked to asbestos exposure, has a long latency. The time between initial exposure and diagnosis averages 25 to 40 years. The bulk of construction in the serpentine areas occurred only in the past 20 years, making any link between disease and housing development virtually impossible to identify.
The current mesothelioma rate on the county’s western slope is slightly higher than expected, but the difference is not statistically significant, according to a California Cancer Registry analysis requested by The Bee.
The study of the most recent reliable data identified 17 mesothelioma patients in the region from 1988 through 1995, compared with 10 cases that would be expected for a population of its size. The victims’ history of residence and occupation are unknown.
Their ages ranged from 59 to 85.
Both amphibole and chrysotile asbestos have been shown to cause mesothelioma and, more commonly, lung cancer.
Numerous studies have led most experts to conclude that amphibole fibers are considerably more potent than chrysotile in the development of mesothelioma.
They are long-lived in the lung, where they can penetrate the linings and induce cancer. Tremolite fibers found in the lungs of veteran Quebec asbestos miners, for example, have equaled or exceeded those of chrysotile – even though tremolite is barely detectable in the ore, studies show.
Several hundred cases of mesothelioma are reported each year in California, and incidence is rising worldwide. Yet asbestos exposure in the mining, insulation and other industries has been declining over the past 30 years due to tightening job protections.
That paradox, and news of The Bee‘s findings, recently inspired UC Davis professor Schenker to propose a statewide study on whether environmental exposure could account in part for the persistence of mesothelioma.
“This concern has been increased because of development and increased populations in regions of the state with naturally occurring asbestos deposits,” a team at UCD and the state Department of Health Services said in a proposal this month to the National Institute of Environmental Health Sciences.
Relatively little is known about exposure to amphibole asbestos outside the workplace. But ways of reducing the risk are at hand.
In 1987, workers excavating for an underground garage in Fairfax County, Va., were itching like crazy. Fairfax health officials traced the source of their discomfort: veins of tremolite asbestos in the serpentine earth. Officials wasted no time surveying the county. Just about everywhere they found serpentine, they found tremolite.
So they mapped the serpentine and set rules more stringent than federal job safety measures to reduce exposure to workers and nearby residents, including air monitors on the perimeter of work sites. Developers cannot build in serpentine without a county-approved protection plan prepared by an industrial hygienist.
“Through all the politicking and wringing of hands and wailing and gnashing of teeth this had caused people inside government and industry here, we just trucked right on and did it anyway,” said Jim Dusek, a county environmental health inspector.
Some developers who at first protested expensive precautions now accept them, if only to avoid lawsuits.
“It’s not in your interest to put somebody out there breathing high concentrations of asbestos…,” said Jerry Naquin, safety officer with the big William A. Hazel Inc. construction firm in Chantilly, Va.
And some California jurisdictions already have precautions against naturally occuring asbestos in planning and building rules.
Officials at the four-person Lake County Air Pollution Control District said common sense led them to adopt rules for home and road building in the serpentine-laced Coast Range.
“If it’s a big problem in demolition or renovation, then it’s of some concern if you are doing construction and moving a bunch of dirt around that happens to be the same stuff,” district Deputy Director Ross Kauper said.
San Jose requires developers within areas of asbestos deposits to mitigate pollution from grading and digging.
Developers of filmmaker George Lucas’ new studios had to have a trained on-site inspector and a safety plan approved by Marin County and Bay Area air pollution regulators before they could plow into serpentine in 1996.
The state Department of Education found that a single line added in 1993 to its checklist for new school sites has been enough to avoid hazards: “If serpentine rock is present, address presence of asbestos.”
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