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This article is the third in a five-part series that won the 1993 AAAS/Westinghouse Science Journalism Award
Superfund: The Road to Nowhere, Day 3
Risk questions remain: The EPA says its Barge Canal cleanup will protect human and wildlife health, but critics say questions are unanswered
From The Burlington Free Press, Feb. 9, 1993
By Nancy Bazilchuk
Burlington resident Jim Garrison is one of few Vermonters who has taken a swim in the Pine Street Barge Canal Superfund site. An inadvertent dip 13 years ago resulted in boils that covered his back, making it impossible for the then-teenager to wear a shirt for a week.
"I was down there with a bunch of friends, and I got pushed in,'' Garrison, 29, said. ''It wouldn't have been so bad, except I hit bottom, and I came up covered in tar.''
Despite Garrison's nasty experience, consultants for the Environmental Protection Agency say the human health risks posed by the Barge Canal are minimal, especially since the state and the EPA combined forces in 1985 to remove 1,500 tons of coal tar from the surface of a small pond in the middle of the site.
The coal tar, which has soaked into an estimated 600,000 cubic yards of soil and sediment, came from an old plant that transferred coal into gas for heating and lighting.
In 1981, the EPA named the Barge Canal one of the 115 worst toxic waste dumps in America. After $5 million and 12 years of study, the federal agency has recommended a controversial $50 million cleanup in which 175,000 cubic yards of the most highly contaminated, tar-soaked soils would be piled into a landfill on the site.
If wetlands destroyed in the process have to be reconstructed somewhere in Burlington instead of the northern end of the site as planned, it will cost an additional $20 million. The EPA says the site must be cleaned up because clams and worms normally found in lake-bottom sediments can't live in parts of the canal where coal tar has pooled. EPA officials say the coal tars pose a long-term threat to these tiny animals and other creatures that live in the 60 acres of wetlands surrounding the canal.
Critics say, however, that the EPA hasn't done its homework. Scientists and environmentalists says the federal agency can't prove there are no human health risks.
"What worries me is that the EPA has not documented any significant health risks from the site,'' said Frank Lowenstein, staff scientist for the Lake Champlain Committee, a watchdog environmental group. ''There are two reasons for that. It could be that there isn't a risk -- or that they didn't collect the right data.''
On the other hand, critics say, the agency doesn't have convincing evidence that the ecosystem is being stressed. At least one scientist says the great risk posed by disturbing the site, contrasted with the uncertainties posed by the contamination, is a good reason to ask whether the site should be disturbed at all.
What concerns critics about the EPA's studies is that they ignore possible avenues of human health threats.
"Unfortunately, from EPA's work, we can't tell if there is something there to worry about,'' Lowenstein said.
There are two areas where Lowenstein says the EPA has left gaping holes.
One is whether toxic substances from the Barge Canal are reaching Lake Champlain, the drinking water source for Burlington and eight towns served by the Champlain Water District. The other is whether toxic air pollutants are wafting out of the contaminated soils.
Lowenstein's concern about the effect of the canal on Lake Champlain was echoed by a University of Vermont scientist.
"Testing Lake Champlain itself wasn't a priority (for the EPA),'' said Richmond Bartlett, a soil scientist at the university. Although the few samples taken by EPA didn't turn up any noxious chemicals, Bartlett worries that not enough samples were taken.
"Perhaps the lake water should be more thoroughly tested,'' he said.
Lowenstein called EPA's lack of information on the effect of the canal on the lake disturbing because the federal agency admitted it didn't have enough samples in the lake.
The same problem applies to air quality, he said.
Although the coal tar is buried in the ground, toxic air pollutants like benzene are found in the tar and can easily turn into a gas and become airborne.
If the soils are dug up, the chemicals might be set free. Even if the soils aren't disturbed, small amounts of the chemicals, some of which are carcinogens, might percolate out into the air.
Air-quality tests
To determine whether the chemicals were leaking into the air, the EPA conducted one day of air testing.
"The air toxics data are not conclusive,'' Lowenstein said. ''They have one day (of samples). That is not enough data to decide if there are health risks from air toxics.''
Furthermore, some of the air samples were accidentally contaminated. That required the EPA to estimate values for some of the most toxic substances.
EPA documents describing the results from the tests for three suspected carcinogens -- benzene, toluene, and 1-1-1 trichloroethane, or TCE -- contradict each other in three places, Lowenstein said.
One document says no contamination was found for any of the chemicals. Another says values for benzene and toluene had to be estimated, while values for TCE were ''significantly higher'' in different samples, indicating there might be a problem.
Another document says TCE values were estimated because technicians had trouble collecting samples. Some benzene and toluene samples were estimated, as well, the document says, because of problems with the instruments that measure the chemicals.
"Those (documents) flatly contradict each other,'' Lowenstein said. Metcalf and Eddy, the Boston-based EPA contractor that wrote the reports, referred questions about the reports to EPA officials.
Not everyone who has reviewed the documents is concerned about the air quality sampling problems, however.
"Even if they had measured everything accurately, I don't think you would find a problem out there,'' said Gary Kjelleren, senior environmental engineer for General Electric Co., one of the companies the EPA says are responsible for paying for the $50 million cleanup.
Many of the highly volatile chemicals that could escape from the coal tars have escaped, Kjelleren said, because the coal tars have been there several decades.
The real air pollution risk would come if the site were excavated, said E. Stanley Corneille, who is overseeing the site for the Vermont Nature Resources Agency.
"Digging that stuff up will release a lot of material to the atmosphere,'' he said.
Jim Schumacher, district director for Rep. Bernard Sanders, I-Vt., said Sanders is concerned about the human health risks from the air pollution resulting from the cleanup plan. Schumacher said he did not think the EPA had examined sufficiently the threat posed by digging up 175,000 cubic yards of coal-tar soaked soil.
"There seems to be no understanding that ... the cleanup may involve some human health risks as you excavate,'' he said. ''What happens to the kids at Champlain School who might breathe this stuff?''
EPA recognizes that digging up the sediments in the canal could release contaminants, said Ross Gilliland, one of the EPA site managers. ''The concerns with ... (air toxic releases) and excavation, we are working on right now'' in order to design a safe plan, he said.
Gilliland attributed the contradictions in the reports on air quality to poor writing. Even though a number of air quality samples had to be estimated, ''no one felt there was enough of a need to go out and do additional air quality sampling,'' he said. ''Nothing jumped out at us to say that we have an ambient air problem.''
Gilliland said if residents expressed concern about the limited data, the EPA would consider additional testing. Nonetheless, he said, the team of scientists that assessed the risk is confident about its work.
The long-term risk we looked at ... are within or very close to the acceptable risk range'' for protecting human health, Gilliland said.
To catch a fish
The biggest problem posed by the Barge Canal, according to the EPA, is the coal-tar laden sediments where clams and worms and other sediment-loving creatures can’t survive. These areas are scattered throughout the canal.
"There is a dead aquatic community out there where the goo is located," said Michael Jasinski, an EPA project manager. If the EPA leaves the coal tars in place, "that would continue to harm the aquatic environment and would continue to contaminate other areas."
Lowenstein was critical of the EPA’s technique for deciding that the clams and worms are at risk. By studying a similar creek in Colchester, EPA concluded that native organisms weren’t surviving.
But the report didn’t collect enough information to make statistically valid comparisons between the two areas, Lowenstein said.
He said the EPA hasn’t proved that the low populations are a result of the coal tar in the sediments. Instead, Lowenstein said, it could be a result of natural differences in parts of Lake Champlain.
Malletts Bay in Colchester has a healthy population of many different kinds of clams, worms and bugs that live in lake-bottom sediments.
In contrast, Burlington Harbor is polluted, and there are fewer, and different species of organisms living there, according to a May 1992 study of the creatures from the University of Vermont’s Water Resources and Lake Studies Center. That might make a difference, Lowenstein said, because the creatures in the lake-bottom sediments colonize the sediments in rivers and streams surrounding Lake Champlain.
EPA says the tar-soaked sediments mean trouble for other creatures, too. An EPA report on the risks posed by the site says, "it is likely… that the fish community is influenced by the contaminated sediments, since species requiring sediment habitat for feeding, spawning or nursery would have limited use of the study area… due to the toxicity of the sediments."
Flawed research
The same report explains, however, why the EPA's assessment of risks to fish is just guesswork.
The technique contractors used to catch bottom-dwelling fish wasn't designed to catch these kinds of fish. Consequently, the EPA used on tow of the bottom-dwelling fish in its assessment. Yet bottom-dwelling fish are most likely to be harmed by the sediments.
To compound the problem, fish samples the EPA tested for toxic accumulation were spoiled. The laboratory held onto the samples too long; that could have allowed chemicals in the fish flesh to evaporate away.
When the laboratory did test the fish, it found no toxic chemicals. There is no way to know whether that is because there are no chemicals in the fish or the toxics simply wafted away before the tests were done, Lowenstein said.
"If you look at their fish data they have found ... (no contamination),'' Lowenstein said. ''Great, that's wonderful -- if you believe the data.''
EPA's Gilleland said the problems identified by Lowenstein aren't an issue.
"The risk assessors feel they have the data to show that there is risk to the wildlife and to the (other) organisms,'' he said.
EPA collected the fish tissue information as a supplement to the basic process, he said.
"We did try to get the fish tissue data because they thought that would help, but the data is unusable,'' Gilleland said, ''but by using the ... (computer modeling processes) they (the risk assessors) felt they had the information to make the decisions they did.''
The questions left hanging by the federal agency pose problems when the EPA's $50 million solution is considered, Lowenstein said.
"It would have been nice while EPA was collecting millions of dollars worth of data on the site if they had gotten us more conclusive evidence on what is happening,'' he said.
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