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New test results show more chromium 6 in Valley water
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PALMDALE - It seems the Antelope Valley's water supply has been deeply touched by a Los Angeles County problem with chromium 6 - maybe more seriously than was previously suspected.
Newly released results of testing on 44 Antelope Valley-area water wells found that 32 of the wells have levels of chromium 6 ranging from 2.8 parts per billion to 17.6 ppb.
Although there is no formal state or federal standard for chromium 6, the state-mandated maximum safe level for total chromium is 50 ppb. The federal standard for total chromium is 100 ppb.
The state Office of Environmental Health Hazard Assessment has recommended drinking water should not have more than 0.2 ppb of chromium 6, but that standard has not been officially established.
Los Angeles County's Environmental Toxicology Bureau conducted the tests as part of a larger round of county testing, ordered by the Los Angeles County Board of Supervisors.
All the wells are owned and operated by the Los Angeles County Department of Public Works.
The locations of the wells tested were: 27 wells in Lancaster; one in Palmdale; three in Kagel Canyon; one in Hi Vista; two in Lake Los Angeles; one in Valyermo; three in Littlerock; three in Acton; and three at the Peter Pitchess Honor Rancho Jail Facility.
Chromium 6 has been suspected of causing cancer, based on the limited amount of research that's been done - mostly on the effects of inhaling the chemical, officials say.
It was at the heart of a 1996 case made famous by the Julia Roberts film "Erin Brockovich," in which residents of the San Bernardino County town of Hinkley won a $333 million settlement from Pacific Gas & Electric because the company's underground tanks leaked chromium 6 into groundwater.
An earlier round of Los Angeles County tests detected elevated levels of chromium 6 in the water at various county facilities, including at the Palmdale Primary Care Center on Palmdale Boulevard. Now scientists are debating just how dangerous the chemical could be to public health.
In late October, a panel of scientists urged state officials to toughen standards for chromium 6 in water, stating there is compelling evidence that it causes cancer.
In testimony during a joint hearing of state regulatory agencies, toxicology professor John Froines of the UCLA School of Public Health said studies have shown chromium 6 to be a carcinogen when inhaled through air, which makes it a likely carcinogen when ingested through water.
The state should quickly take action to purge water supplies of the chemical, even though scientists and regulators are still debating its risk, said Froines, chairman of the advisory board for the state Office of Environmental Health Hazard Assessment.
"You can take the political, legal and economic argument (against the tougher standard), and it will go on for 10 years," Froines said. "We should assume the correctness of the state's public health goal for chromium 6 and begin from there."
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Chromium concentrations in wells at Air Force Plant 42 are near, but do not exceed, the state standard of 50 parts per billion. Valley Press Staff Writer Brenda Zahn reports.
Plant 42 chromium level near state limit
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LANCASTER - Chromium concentrations in wells at Air Force Plant 42 are near, but do not exceed, the state standard of 50 parts per billion.
"Those were found both in production and monitoring wells, but that highest concentration was found in a monitoring well," said John Lovenburg, project manager/senior hydrogeologist for the consulting firm CH2MHill, which is helping the Air Force facility clean up its groundwater contamination.
Air Force Plant 42 began testing and monitoring its wells after concerns were raised around the county about possible elevated levels of the element in water. However, the Palmdale facility is not taking any remediation action to reduce that chromium level because it does not exceed state standards.
If the chromium level in the wells at the plant exceeds that standard, the water from that well cannot be used.
Levels of chromium 6, the much discussed carcinogenic element of total chromium that was recently discovered in wells around Los Angeles County, ranged from nondetect to 20 ppb.
Chromium 6 can come from various sources, including rust inhibitors in cooling towers, textile dyes and pigments, bricks in furnaces, steel manufacturing, chrome plating, leather tanning and wood preservatives.
The chromium at Plant 42 most likely came from painting operations, Lovenburg said, and from alodine, which is used for metal surface preparation at Plant 42.
The contamination probably occurred in the 1950s and 1960s, he said.
"This presentation kind of covers a chromium 101, if you will," Lovenburg said as he introduced the subject at the Wednesday night meeting of Plant 42's Environmental Restoration Advisory Board.
Plant 42 test results followed a wave of other results released in recent months that have the public confused and concerned.
Recent testing of 110 county facilities showed elevated levels of chromium 6 at several sites. A second round of tests on 44 Antelope Valley-area water wells found that 32 of the wells have levels of chromium 6 ranging from 2.8 ppb to 17.6 ppb.
Although there is no formal state or federal standard for chromium 6, the state-mandated maximum safe level for total chromium is 50 ppb. The federal standard for total chromium is 100 ppb.
The state Office of Environmental Health Hazard Assessment has recommended a public health goal of 2.5 ppb and a public health goal of 0.2 ppb for chromium 6.
Total chromium consists of the nutrient chromium 3 and the carcinogen chromium 6; some speculate, although the theory has not been thoroughly tested, that chromium 6 may be reduced to chromium 3 in the stomach when ingested.
Chromium 6 testing on mice more about 40 years ago suggested that chromium 6 may cause cancer. But there has not been much testing on its effects when ingested by humans.
Recent testing in L.A. County has shown that it caused cancer in people who inhaled it through occupational exposure.
Chromium 6 concerns surfaced after a 1996 court case made famous by the Julia Roberts film "Erin Brockovich," in which residents of the San Bernardino County town of Hinkley won a $333 million settlement from Pacific Gas & Electric because the company's underground tanks leaked chromium 6 into groundwater.
In Hinkley, chromium 6 levels were found to be hundreds of times higher than typical water supply levels.
Lovenburg explained that chromium is the 11th most common element in Earth's crust and that it's found in the air, soil, water and food. Some 93% to 98% of total chromium intake by humans is from food, and 2% to 7% is from water, he said.
The base found chromium 6 above reporting levels in the soil at three of its sites. The highest soil concentration was 44.1 parts per million. The chemical is measured in parts per million in the soil and parts per billion in the water.
The U.S. Environmental Protection Agency Region 9 has established an industrial site preliminary remediation goal of 64 ppm for chromium 6 in the soil.
The board meets regularly to oversee the Air Force's cleanup process at Plant 42. At its next meeting, officials will offer board members an overview of the Antelope Valley's chromium 6 problem so they can put Plant 42's levels into perspective, Lovenburg said.
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Past dumping practices at Edwards Air Force Base have contributed to one of the largest plumes of groundwater contaminants under the Air Force Research Laboratory Propulsion Directorate on the remote northern edge of the base. Valley Press Staff Writer Julie M. Drake reports.
System set to adsorb contaminants
By JULIE M. DRAKE
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EDWARDS AFB - More than 25 years ago, solvents or materials that were no longer viable were often dumped into a pit and left to evaporate or seep into the ground.
As experts learned years later, the contaminants didn't just disappear, they remained in the ground. At Edwards, past practices contributed to one of the largest plumes of groundwater contaminants, under the Air Force Research Laboratory Propulsion Directorate on the remote northern edge of the base.
Borrowing technology used in many homes, the U.S. Force installed a granular activated carbon adsorption system to remove contaminants from groundwater under the lab.
Total cost of the system is approximately $1 million to build and maintain it for one year, after which it is projected to cost about $18,000 a month to operate.
"This actually is a treatability study," said Gary Hatch, chief of environmental public affairs.
Hatch said Site 133, the groundwater plume under the lab, was picked because it was the largest plume in the area, although not in contaminants.
The groundwater isn't used for drinking water but contaminants - primarily trichloroethene - in it exceed regulatory limits. The limit for TCE is 5 parts per billion, but concentrations of it have been measured as high as 6,100 ppb.
Other contaminants include tetrachloroethene, the gasoline additive methyl tertiary butyl ether and N-nitrosodimethylamine, a rocket fuel additive.
The plume extends nearly 2 miles down the south side of the laboratory, near the center of the base bombing range. Wednesday morning, the Air Force announced its part in cleaning up the plume.
A GAC is similar to the type of water charcoal filter used to clean tap water. Through adsorption, contaminants stick to the surface instead of being absorbed.
Granted, the Air Force wasn't alone in its practices, but as Col. Wesley Cox, director of the AFRL said, the ribbon-cutting was a way to recognize "efforts to correct the results of past practices. These are practices of a bygone era, They're not our current practices."
Hood said the Air Force has committed approximately $35 million and $40 million for the cleanup of all Edwards sites.
Eric Lang, senior engineer with Earth Tech Inc., a base contractor heavily involved with project, said the system is designed to operate at 50 gallons a minute, although it is currently permitted for 20 gallons a minutes, or 29,000 gallons a day.
Three large tanks, each of which holds approximately 2,000 pounds of GAC, are available to clean out contaminants, although Lang said only one would be used at a time, with the other two available for backup.
Bob Wood, chief of environmental restoration at Edwards, said the system will be used for approximately 18 months as its effectiveness is gauged.
Wood said several methods were used to determine the best location for the extraction wells. The treatment system pulls water from wells dug approximately 150 feet in the ground. The plume is located within fractured bedrock.
"Before you start treating something, you better figure out where it is and where it's going," Wood said.
He added that if the system works, it can be expanded by adding more pipes and wells. The tanks also can be recycled and used on other base sites.
"We try to make it pretty. It's somewhere between a dairy and a refinery," Woods said, then added, "It's important we don't make a new mess when we're cleaning up the old one."
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Tests of tap water at county facilities reveal higher levels of
carcinogens than certain state and federal recommendations, with
numerous Lancaster locations topping the lists. Valley Press Staff
Writer Lisa Wahla reports.
Contaminants high in county water tests
By LISA WAHLA
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LOS ANGELES - Tests of tap water at county facilities reveal higher
levels of carcinogens than certain state and federal recommendations,
with numerous Lancaster locations topping the lists.
The levels of chromium 6, total chromium, arsenic and lead in the
water still fall below the maximum levels allowed by state and
federal regulators, county officials said.
Supervisor Michael D. Antonovich, whose 5th District includes the
Antelope Valley, urged the studies and announced their results
Wednesday. He said the figures demonstrate a countywide water
contamination problem and the need for stricter, more uniform
standards.
County toxicologists, who took drinking water samples from 990
facilities, also tested 57 brands of bottled water for the same four
carcinogens. All fell within the state standards for the carcinogens,
but some tested above the levels recommended by the state Office of
Environmental Health Hazard Assessment.
California's standard for total chromium, a combination of harmless
chromium 3 and the carcinogen chromium 6, is 50 parts per billion.
The state has not set a standard for chromium 6.
The hazard assessment office, however, recommends a public health
goal of 2.5 ppb for total chromium and 0.25 ppb for chromium 6.
The county also tested for arsenic: The state standard for arsenic is
50 ppb, but federal regulators are discussing lowering that to 10 ppb.
In 1999, a National Academy of Sciences report found arsenic in
drinking water causes bladder, lung and skin cancer, and might cause
kidney and liver cancer.
While chromium 6 testing on mice about 40 years ago suggested that
chromium 6 may cause cancer, not much testing has been done on its
effects when ingested by humans.
Recent testing in L.A. County showed that chromium 6 caused cancer in
people who inhaled it through occupational exposure.
Chromium 6 concerns surfaced after a 1996 court case made famous by
the Julia Roberts film "Erin Brockovich," in which residents of the
San Bernardino County town of Hinkley won a $333 million settlement
from Pacific Gas & Electric Co. because the company's underground
tanks leaked chromium 6 into groundwater.
Water from several Lancaster facilities far exceeded the public
health goal for chromium and some went beyond the proposed lower
federal standard for arsenic.
The county facility with highest levels of total chromium and
chromium 6 was the Fire Department's Station 130 on 40th Street West,
which showed results of 15.9 and 13.1 ppb, respectively, along with
9.7 ppb for arsenic.
Other facilities with heightened levels included Fire Station 117 on
30th Street East, which showed 7.39 ppb for total chromium, 6.99 ppb
for chromium 6 and 13.4 ppb for arsenic, and the Department of
Children and Family Services administrative office on Avenue K-4,
which tested at 11.4 ppb for total chromium and 5.8 ppb for chromium
6.
A Public Works sewer maintenance yard at 45712 Division St. tested at
11 ppb for total chromium, 10.2 ppb for chromium 6 and 36.8 ppb for
arsenic, while a Waterworks office at 419 West Ave. J tested at 10.3
ppb for total chromium, 9.78 ppb for chromium 6 and 12.7 ppb for
arsenic.
Across the county, toxicologists found 147 facilities, about 15%,
with total chromium levels above the public health goal of 2.5 ppb.
For chromium 6, the figure was higher: 412 facilities, or more than
40%, tested above the goal of 0.25 ppb.
Antonovich has pushed state and federal regulators to lower the
maximum carcinogen levels allowed in water to the public health goal.
He said he and the other supervisors will meet again with federal
Environmental Protection Agency officials next month in Washington,
D.C.
"The state and federal government must establish uniform standards
and protocols," Antonovich said. "We should have zero tolerance for
carcinogens in the water."
Wednesday's announcement follows last year's tests of 44 AV wells,
which found 32 wells with levels of chromium 6 ranging from 2.8 to
17.6 ppb.
As for the tests of bottled water, the brand Fiji tested for total
chromium at 2.67 ppb. Eleven water brands tested above 0.25 ppb for
chromium 6.
This story appeared in the Antelope Valley Press November 10, 2000
By BRENDA ZAHN
Valley Press Staff Writer
This story appeared in the Antelope Valley Press December 15, 2000
By BRENDA ZAHN
Valley Press Staff Writer
The chemical is in the facility's drinking water wells and monitoring wells in concentrations ranging from 3 to 47 ppb.
This story appeared in the Antelope Valley Press May 17, 2001.
Valley Press Staff Writer
Out of sight, out of mind?
This story appeared in the Antelope Valley Press August 16, 2001.
Valley Press Staff Writer
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