19 January 2003
chemicals taint Barton waters
Pool, other city creeks may pose health risk; decades-old fuel waste
cited as possible source
By Kevin Carmody and Mike Ward
of toxic chemicals in Barton Springs Pool and just upstream on a
hillside overlooking the pool have exceeded those found in a dozen
of the worst hazardous waste sites in the country, an Austin American-Statesman
investigation has found.
points along three other Austin bodies of water — East Bouldin
Creek, Waller Creek and the Central Market ponds at Lamar Boulevard
and West 45th Street — levels of chemicals that increase the
risk of cancer after prolonged exposure also have exceeded those
found at toxic waste sites that federal authorities have declared
public health hazards or Superfund sites.
who reviewed test results documenting the contamination say the
data suggest that the pollution found in the pool and along the
hillside is from hazardous waste dumped nearby. The most likely
culprit, they say, is waste from coal gasification plants that produced
fuel for city lighting from the 1870s to 1928.
toxicologists said the elevated levels of the neurotoxic metal arsenic
and seven benzene-based compounds found in sediments at Barton Springs
warrant temporarily closing Austin's environmental treasure, the
spring-fed pool whose iconic value has driven more than a decade
of anti-development campaigning and reshaped city politics. They
recommend closing the pool until questions about public safety are
resolved. The pool attracts an average of about 1,000 paid visitors
figure, adapted from the American-Statesman (original
PDF), compares Barton Springs PAH levels with EPA standards
and with contamination levels at other sites. Units are parts per
billion benzo(a)pyrene equivalents.
also recommend that warning signs be posted to alert swimmers and
fishermen to risks and that site assessments be done at the worst
areas to document the extent and source of the contamination.
the city found the chemicals in the springs area as early as 1994,
its focus in its testing program was on the endangered Barton Springs
salamander and not on human health, city officials acknowledge.
newspaper's findings go beyond its report in August, which showed
that the presence of one benzene-based chemical, benzo(a)pyrene,
sometimes exceeded state safety guidelines at the pool and on the
hillside. Atop that hillside sit the Barton Springs Park Place apartments,
at 1200 Barton Hills Drive in the Barton Hills neighborhood.
officials said then that the carcinogen was not detected often enough
to close the pool or pose any health concern for people.
city maintained its position until Jan. 10, when nine city officials
and their consultants met with editors and reporters of the American-Statesman.
Because of the seriousness of the findings, the newspaper wanted
to give the city a briefing and another opportunity for response
the Jan. 10 meeting, City Manager Toby Futrell ordered her staff
to take samples of sediment in the pool and Barton Creek on Jan.
Tuesday, the top public health authority in Austin and Travis County
said that he and city officials now realize the hillside may pose
a risk and needs a full assessment but that they don't have enough
information about the level of exposure in the pool to know whether
it poses a risk to swimmers.
think we all agree that we have a problem on the hillside,"
Dr. Ed Sherwood said. "I don't think there's any question about
officials said they think seal coat treatments on streets and parking
lots are the cause of the hillside contamination.
newspaper's new findings suggest that swimmers in the pool and Barton
Creek have been exposed not just to one contaminant but to a toxic
stew of tainted sediment at least periodically for seven years,
probably longer. The findings detail problems with arsenic and polycyclic
aromatic hydrocarbons, a family of more than 100 chemicals known
of those benzene-based chemicals — one of them benzo(a)pyrene
— are the most dangerous of the PAH family, federal health
officials say. The newspaper's findings are based on city tests
of sediment and soil from 1991 to 2002 and a review of 11,000 pages
of city documents obtained under the Texas open records law.
six experts who provided a detailed assessment of the test results
said the extraordinarily high levels and the number of contaminants
found upstream in Barton Creek and on the hillside, including neurotoxins
such as mercury and the pesticide heptachlor, indicate there may
be previously unknown hazardous waste sites nearby.
is possible, the newspaper's experts said, that the pollution came
from coal gasification plants whose wastes might have been dumped
on the ground or in an old gravel pit that was filled in before
the Barton Hills neighborhood developed.
e-mail obtained from the city under the Texas open records law shows
that the serious nature of the contamination at the pool, creek
and hillside had independent confirmation in early 2002 by scientists
with the U.S. Geological Survey, the federal government's sciences
research arm. A federal scientist reported to city officials that
she was shocked by the "astronomical" levels of benzene
compounds recorded in USGS tests.
Van Metre, another USGS scientist who advises the city on water
quality issues, told the newspaper he cautioned city staff that
the levels upstream, particularly on the hillside creek bed, were
higher than his agency had ever detected anywhere in the country
in routine surveys of waterways. Those levels would be expected
"at a contaminated industrial site," Van Metre said he
told them in May 2001.
newspaper also found elevated levels of the benzene compounds. In
December, sediment from shallow areas along the northwest side of
the pool was collected by two reporters and sent to a state-certified
lab in Round Rock, DHL Analytical Inc., for analysis. The tests
showed levels of benzene compounds higher than the U.S. Environmental
Protection Agency has deemed safe for regular human contact.
hillside contains a tree-lined dry creek bed as deep as 6 feet in
some places with its upper portions strewn with rock, concrete and
chunks of asphalt. When rain falls, the water flows to Barton Creek
hillside has repeatedly recorded the seven benzene compounds above
the minimum level of 1,000 parts per billion that can make a residential
or recreational area eligible for the federal Superfund list of
the nation's most dangerous toxic sites needing cleanup. In one
test, the compounds were found at 355 times that minimum.
seven benzene compounds are listed by federal and international
health agencies as either probable or possible human carcinogens.
Arsenic is considered a known human carcinogen.
EPA assumes that a safe level of the seven benzene compounds in
the soil or sediment is 90 ppb or below. In the pool, the peak levels
have been up to nearly 100 times higher, and nearly nine times the
minimum that can qualify a site in a recreational or residential
setting for a federal Superfund cleanup.
think the other locations with elevated levels of the benzene compounds
— East Bouldin Creek, Waller Creek and the Central Market
ponds — could have become contaminated by a variety of sources,
including coal gas waste and leaking underground petroleum storage
four other areas, along Shoal, Blunn and Harper's Branch creeks
and Taylor Slough, the city's tests have recorded contaminant levels
that exceed some state or federal safety guidelines. However, according
to the EPA, the levels of chemicals and apparently low frequency
of human exposure at most of those sites might not be great enough
for action under the federal Superfund law.
the country, about 600 sites contaminated with the benzene compounds
have qualified for Superfund cleanups. Documents and interviews
with EPA Superfund staff identified a dozen sites where the benzene
compounds were among the primary pollution concerns and were found
at levels comparable to or lower than some of the Austin sites.
New Hampshire, the Agency for Toxic Substances and Disease Registry,
a branch of the federal Centers for Disease Control and Prevention,
declared a public health hazard and banned swimming in the Winnipesaukee
River near the former Messer Street Manufactured Gas Plant. Contamination
of shallow sediment in the river in comparable samples had peak
levels lower than the peak found in Barton Springs Pool.
suburban Houston, Patrick Bayou joined the Superfund priority list
on Sept. 5. It also had peak readings of the benzene compounds at
lower levels than the peak detected in the pool and at about half
the level the City of Austin detected in November 2000.
Conroe, the United Creosote site made the list with levels of soil
contamination significantly lower in comparable samples than what
has been recorded on the Barton Creek hillside.
city knew about the high levels of the benzene compounds in the
pool as early as 1995. City officials had mentioned the chemicals
in several reports to the City Council and other government agencies.
The reports were available but not widely distributed to the public.
They typically suggested the chemicals might pose a threat to the
endangered salamander but did not address whether they might be
harmful to people.
the American-Statesman's August article prominently stated that
a state toxicologist said there was no immediate health risk at
the pool, city officials denounced the article as unnecessarily
scary and "inappropriate."
officials hired toxicologists to assess the health effects information
on Jan. 10, and they started working immediately.
the meeting at the American-Statesman, the city officials were asked
how they could have failed to seek a human health assessment between
1995, when the pool recorded its first high measurement of the benzene
compounds, and 2002, when salamanders started dying mysteriously.
didn't look at it from a human health perspective," said Nancy
McClintock, manager of the Environmental Resource Management Division.
She said the city tested three months later and could find nothing.
officials did emphasize they had expanded the waterways testing
program in 1997. They began looking upstream for the source of the
pool's benzene compounds they thought might be threatening the salamanders.
early 1998 those tests identified the hillside and another area
on the opposite bank as the likely sources. The city put a project
designed to stop erosion on the hillside into its capital improvement
program in 1999, but design work did not start until after the Statesman's
story in August.
Austin, no official data exist about health problems that might
stem from the pollution. It is known that a city biologist and three
swimmers have experienced rashes or skin problems after being in
the pool or Barton Creek. Last year, city scientists discovered
endangered salamanders dying from a mysterious disease that produced
blisterlike gas bubbles under their skin.
benzene compounds can increase one's risk of developing various
cancers after long-term exposure. At relatively low exposures, those
contaminants and arsenic can cause subtle neurological problems,
including memory loss and behavioral changes if swallowed or absorbed
through skin, according to medical literature and the newspaper's
level of risk is always difficult to assess at contaminated sites,
even at Superfund sites extensively investigated, the toxicologists
depends on the frequency and level of exposure and a person's unique
genetic makeup. Children typically ingest more soil or sediment
than adults and may be more sensitive to certain contaminants. They
could face a greater risk than adults do — particularly if
they play in and along Barton Creek above the pool, the toxicologists
toxicologists and several other experts urged caution for all swimmers.
The crude nature of the city's tests in the pool, combined with
the city's four detections of relatively high levels, offer more
questions than answers — questions begging for a thorough
site assessment, they said.
you think there may be harm, even though you are not sure, it's
best to use prudent avoidance," said David Palmerton, a certified
hazardous materials manager and owner of an Upstate New York-based
company that coordinates the cleanup of contaminated sites for Fortune
expert who advises closing Barton Springs Pool is Marvin Legator,
longtime director of an environmental toxicology program at the
University of Texas Medical Branch in Galveston and a former chief
of genetic toxicology at the U.S. Food and Drug Administration.
matter how we look at it, the data really present to us a highly
contaminated area," he said, referring to the Barton Springs
area and the other three most contaminated sites. "If we confirm
the measurements as they are, I would certainly think of just closing
it (the pool) down till it's cleaned up. . . . If we have an individual
who swims just once a month, I don't think that's really a threatening
thing. However, if we have somebody who swims five days out of the
week, that would be a real concern."
pool has daily swimmers year-round.
concern for swimmers' health was echoed by Patricia Williams, who
teaches toxicology at the Louisiana State University School of Medicine
in Shreveport and studied the health effects at the Lincoln Creosote
Superfund site near Shreveport. She was surprised by the high levels
of the benzene compounds in Barton Springs Pool and upstream. "I
know of nothing in a natural setting, with this level of human exposure,
that has a contamination level like that," she said.
than Legator, the other five primary experts said they didn't have
the medical expertise to assess the extent of health risks in the
pool. But three — Palmerton, Allen Hatheway, a retired University
of Missouri professor of geology and past president of the Association
of Engineering Geologists, and Michael Stenstrom, associate dean
and professor, UCLA School of Engineering and Applied Science —
city should issue advisories or post warning signs at the pool and
other sites alerting swimmers and fishermen to the contamination
if experienced toxicologists suspected a possible human health threat,
they said. Along with Williams and Legator, they said a detailed
assessment of the most contaminated sites was warranted.
for the hillside 80 yards upstream from Barton Springs and on the
left for a person walking west: In the opinion of the newspaper's
experts and environmental officials, it poses a far more serious
problem than the pool.
on the levels I'm hearing, in a residential setting next to apartments,
a cleanup is certainly warranted," said John Meyer, an EPA
manager for Superfund cleanups in the five-state region that includes
Texas and the one who managed the cleanup at the Lincoln Creosote
site in Louisiana. "A lot of times that falls under what we
call time-critical removal, rather than the normal remediation process
that can take many years to complete. Based on the immediacy of
the risk, you take immediate action."
ground-level concrete patios at the Barton Hills Park Place apartments
on top of the hill are as few as 15 feet from the dry creek bed,
where levels of benzene compounds in the city's two initial tests
were seven and nine times higher than in residential surface soils
at the Lincoln Superfund site in Louisiana.
pollution at Lincoln Creosote has, in a study by LSU Medical School
staff, been associated with increased levels of cancer and other
diseases. At Lincoln, the benzene compounds migrated into adjoining
neighborhoods and drainage ditches where children played.
the sites around Austin, the levels of the various contaminants
vary widely site to site, suggesting there would likely be different
levels of risk, the experts said.
Creek, north of 24th Street near the University of Texas campus,
recorded the highest level of the benzene compounds of any location
in the city. That site has not been retested since the August 2000
level of toxic lead reported in that 2000 test was nearly three
times the level that can prompt a Superfund cleanup when found in
soil and nearly 15 times the level in soils that medical researchers
have found to cause reduced brain function in children playing in
soil guidelines can be used to assess contaminated sediments where
there is regular human exposure in residential or recreational settings,
an EPA Superfund manager and an EPA toxicologist said.)
Janssen, head of the University of Texas environmental safety office,
said he was shocked by the high level of lead recorded. His staff
will investigate possible sources of the lead and the benzene-based
compounds. Drainage from around the engineering school and the university
power plant enters Waller Creek near 24th Street, Janssen said.
is no information available on whether or how often children might
play in or near the most contaminated spot. Children do play and
fish in Waller Creek in areas several blocks downstream, where contamination
who study benzene compounds say it is possible that the source of
contamination at Waller Creek is something other than coal gasification,
perhaps a leaking petroleum storage tank.
three Central Market ponds were designed by the city to help capture
sediment flowing through a tributary of Shoal Creek. The city officials
said they expected these ponds to capture pollutants.
the levels of the benzene compounds and metals are high enough to
pose a health risk for anyone who may wade in the ponds and possibly
for those who regularly play at the edge; at the very least, signs
should be posted as a warning about potential risks, according to
the newspaper's toxicologists.
gasification was a method used during the 1800s and early 1900s
to extract gas from coal for use in street and home lighting. The
resulting wastes contained high levels of the benzene compounds,
mercury, arsenic and ammonia.
had at least three manufactured gas plants downtown after the early
1870s. Two were coal gasification plants. The third used wood products
in its gas-making process.
gas makers would take to, as they say in Texas, 'getting shut' of
the wastes by dumping them in other nearby depressions in the ground,"
said Hatheway, the retired University of Missouri geology professor
who is considered the nation's top expert on coal gasification sites.
tainted soils above Barton Springs are near what in the late 1800s
was a primary road from Austin to points west, including Bee Cave.
The stone bridge that crossed Barton Creek on that early-day trade
road washed out in 1900.
city also had several ice plants in the mid-1800s — one of
which was operating downstream from Barton Springs Pool at a grist
mill by about 1875. Ice plants sometimes used small coal gasification
units to provide energy and produce ammonia as a refrigerant. It
is unknown whether the ice plant at Barton Springs had such a unit.
successful cleanup of the upstream site could halt the flow of most
benzene compounds and metals into the pool and Barton Creek. But
it could be costly and difficult, depending on the amount of waste
and whether it is below a small or large section of the Barton Hills
neighborhood, the experts said.
limestone aquifer system in Austin makes remediation "very
difficult . . . if (contamination) has entered the ground water
or is transported as particles though bedrock fractures," said
Palmerton, the hazardous materials manager. "Typical gas plant
sites . . . can cost tens of millions of dollars to investigate
is unknown whether ground water in or near the Barton Creek sites
is contaminated with the benzene compounds.
officials theorize that the benzene compounds from the hillside
enter the pool only when floods spill over the dam at the upstream
end of the pool. The levels of the benzene compounds found upstream
and in the pool, and recent Geological Survey tests of the suspended
sediment entering the pool from the springs, appear to support the
city's explanation of how the tainted sediment typically enters
city has said there is no human health concern because some floods
leave little sediment in the pool and the shallow areas often contain
little sediment. That view, however, doesn't hold up to a toxicologist's
don't quite see the city's argument on this," said Legator,
the University of Texas toxicologist. "If we're getting those
measurements . . . and this is where everybody is swimming, they're
city also argues that because the tests showed 19 nondetections
of contaminants over 11 years, the problem is intermittent and therefore
not risky. The experts don't see it that way.
not appropriate," said Paul Templet, former head of Louisiana's
environmental agency. "If just one analysis exceeds a standard,
you want to look a lot more closely, . . . and somebody ought to
take a closer look at this situation."
a few weeks ago, city scientists never attempted to test the shallow
end of the pool, where hundreds of children frolic in a few inches
to a few feet of water on many summer days. After initially rebuffing
suggestions to test the shallow end and other shallow areas in which
adults might walk and be exposed to tainted sediment, the city tried
to collect sediment samples in the shallow end on Nov. 14.
wasn't enough to get a valid sample," said Ed Peacock, a member
of the city's watershed protection staff.
a month, members of the American-Statesman staff, using the city's
sample collection protocols, collected a sediment sample from the
shallow end that was deemed adequate by a state-certified lab.
weekend the city staff tested at sites around Barton Creek and three
locations in the pool, including the shallow end. The results showed
lower levels of the seven benzene compounds in soil than in previous
tests at the hillside. The shallow end of the pool recorded levels
of two benzene compounds at 8 ppb in the sediment — significantly
lower than the EPA's health-effects threshold of 90 ppb.
arsenic levels in the sediment were 3,640 ppb, far above the 400
ppb screening level the EPA has deemed safe in most locations. A
sample of sediment in a deeper part of the pool showed a level of
880 ppb of the seven benzene compounds, below the 1,000 ppb that
can lead to EPA action under the Superfund program. Arsenic levels
were 5,540 ppb.
also a mystery
Thursday, the Texas Commission on Environmental Quality, the Texas
equivalent of the EPA, began testing throughout the Barton Springs
literature describes the pool as "one of the crown jewels of
Austin." It attracts 350,000 paid visits a year and as many
as 500,000 visitors, including free after-hours visits.
is not unusual for the city to close the pool during and after heavy
rains, but not because of benzene compounds. It happens when water
testing finds elevated levels of bacteria that can cause gastrointestinal
problematic than benzene compounds for the pool's future may be
the arsenic that federal scientists recently found flowing directly
from the spring itself, attached to sediment at levels that Legator
and other toxicologists consider too high for regular human exposure.
source of the arsenic is not known, although some soils have naturally
elevated arsenic levels. Tainted runoff into creeks miles from the
pool could be contaminating the aquifer that feeds the springs,
city officials said.
EPA recently reevaluated the risk of arsenic in drinking water,
based on new studies showing the metal is more toxic and carcinogenic
than previously thought. Despite resistance from the Bush White
House, the EPA lowered the acceptable level in drinking water from
50 to 10 parts per billion.
one occasion, in November 1995, the city detected arsenic in the
pool water at 46 parts per billion. The typical readings at the
pool are 1 or 2 parts per billion.
levels of arsenic in suspended sediment entering the pool range
from 17,800 to 22,300 parts per billion, according to city records
of Geological Survey tests from 1999 to 2002. In the sediment on
the bottom of the pool, the levels have been measured as high as
13,600 parts per billion, by the city in May 2001.
PAHs together with metals such as arsenic, you'll want to look at
whether there is an increase in birth defects," Williams said.
"Arsenic is a particularly bad actor, and for exposed individuals,
there may be a wide range of cancer and noncancer effects occurring."
is a cumulative poison, Williams said, so it will build up in the
body a little bit more each time someone is exposed, particularly
accumulating in the testes and affecting sperm.
have the question of what's going to happen to the next generation,"