Download Coal Tar Presentation - Fox River Ecosystem Partnership

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BACOG is a regional planning organization with 8 municipal and township members,
in 85 square miles and parts of 4 counties.
BACOG Water Resources Committee – charged with study, policy recommendation &
education on groundwater.
Studied others groups’ plans and documents, including McHenry County’s WRAP –
which included the coal tar topic – first awareness.
Last 5 years, Committee studied and recommended policies and programs to
BACOG’s Executive Board:
--Salting
--Private well water testing
--Coal Tar – kept returning to this issue
So about a year ago, started studying coal tar and found much to be concerned
about.
So what are we talking about? Sealants are the thick liquid coating that people put
on top of asphalt pavement to bring a glossy, dark, restored appearance to driveways,
parking lots, tennis courts, bike paths, and similar asphalt surfaces. They are not
generally used on roads.
They do provide a small amount of protection to the asphalt surface but not a lot –
that is not their primary function – it’s mostly about appearance.
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Sealants in this part of the country, the eastern part of the United States mainly, are
mostly coal tar based – when commercially applied anyway.
Mostly what is found in gallon buckets on the shelves of big retailers is NOT coal tar
based these days.
Coal tar is an industrial by-product of manufacturing in the steel industry. Instead of
paying to get rid of this waste product, the industry can sell it for use as an additive to
sealants. The choice is clear: pay or sell.
The problem is that coal tar contains a very high level of polycyclic aromatic
hydrocarbons – or PAHs.
Many PAHs are carcinogenic, mutagenic and cause cell and DNA damage in
organisms.
PAHs come off seal-coated surfaces as little flakes, as dust, and can be inhaled,
ingested and absorbed through the skin.
--PAHs are mobile and move with stormwater into ponds, lakes and waterways.
--They come off sealed surfaces by the action of sunlight and go into the air as dust.
--And PAHs are tracked off surfaces by vehicles and foot traffic and get onto and into
people in their homes.
PAHs have some really bad effects on aquatic life and on human health. That’s why
we’re concerned.
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PAHs were isolated in the 1920’s and early scientists soon determined that many
were intensely carcinogenic. There had been anecdotal associations between
exposure to coal tar (and other coal production products) and the development of
tumors and cancers, and between the production of some dyes from coal tar and
bladder cancer. By the early 1930s, scientists understood that PAHs are metabolized
in the bodies of organisms and people, becoming carcinogenic, and PAHs could be
absorbed through skin contact, breathing, or ingestion.1
Early scientists also recognized the persistence of PAHs in the environment.
PAHs became part of standard testing protocols for pollution, along with pesticides
and metals.
1. PAHs and Related Compounds: Chemistry. edited by Alasdair N.Nelson, Springer,
Nov 11, 2013.From the introduction, pp XVIII
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PAHs became part of standard testing protocols for pollution, along with pesticides
and metals. When the United States Geological Survey in the early 1990’s was tasked
with assaying water quality and trends using lake sediment cores, they followed the
standard protocols. PAHs had long been on the EPA Priority Pollution list for control.
In 1992, for some reason for unknown reasons, the EPA excluded coke product
residues, including coal tar, from classification as hazardous wastes if they are
“recycled.” Under the Resource Conservation and Recovery Act, coal tar-based
pavement sealants contain recycled coal tar and, therefore, are not regulated. They
still have the heavy PAH load. Red flags were raised, but the EPA did nothing.
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As part of the National Water-Quality Assessment (NAWQA) program, USGS
discovered that while some pesticides and other toxic pollutants like PCBs and DDT
were declining, PAHs were increasing, and significantly.
As you know, PAHs are a product of incomplete combustion, and are everywhere.
The challenge was to find out the source or sources.
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Also in the early 2000’s, Austin, TX was investigating pollution at Barton Springs, a
huge complex of natural springs and a favorite place for swimming. In January, 2003,
the pool was closed for 90 days for environmental testing. Austin received a grant to
analyze sediments in streams and drainage ditches, as part of the investigation.
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A curious Austin investigator walked up the drainage channel from a PAH “hot spot,”
found a recently sealed parking lot…. Sealed with coal tar. He made the connection.
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Coal Tar sealed pavements were not implicated as an issue with Barton Springs
(arsenic and several benzenes), but they were now on the radar for the increase in
PAHs in urban lakes.
This slide notes the difference in PAHs given off with Coal Tar based sealants (red)
versus those given off from Asphalt based emulsions (blue). Coal Tar is significantly
more toxic. In Lake-in-the-Hills, USGS researchers found that driveway dust was
contaminated with extremely high levels of benzo[a]pyrene, one of the most toxic
PAHs. The amount was 5,300 times higher than the level that triggers an EPA
Superfund cleanup at polluted industrial sites. As Barbara Mahler, a USGS researcher
involved in the studies observed,” Such high concentrations usually are found at
Superfund sites, but this could be your church parking lot or your school playground,
or even your own driveway.”
I should also point out that it is generally at the 23 mg/kg level that biota impacts are
observed
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IARC classified coal tar pitch as a Class 1 Human Carcinogen: There is sufficient
evidence in humans for the carcinogenicity of occupational exposures during paving
and roofing with coal-tar pitch. There is sufficient evidence in experimental animals
for the carcinogenicity of coal-tar pitch.
Aggravated Medical Conditions include Respiratory disorders, skin disorders, preexisting eye disorders, central nervous system.
Those PAHs are powerful.
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PAHs are ubiquitous in our lives. Coal-tar-based sealants are an especially large and
concentrated source.
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Obviously, with all of those different kinds of PAHs, how did the USGS determine that
coal tar based sealants was the primary polluter?
Chemical fingerprints!
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A more technical test was done with EPA resources which gives a telling picture of the
major sources of PAHs in U.S. Urban Lakes. Sealcoat is a major contributor.
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There was a rainstorm not long after a parking lot was sealed near Hodge’s Creek,
North Carolina, resulting in a significant fish kill just downstream.
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The USGS found that coal tar sealcoated surfaces continued to give off PAHs for a
considerably longer time than industry admitted, meaning continuing effects on
aquatic life…… and, as we will see…. People.
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Because some PAHs are phototoxic, it was important to see the effects on these
organisms with Ultraviolet light exposure in the testing regimen.
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As you can see, exposure is devastating to the water flea, especially so with sunlight.
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Significant mortality. They did not test beyond 111 days, but you can see that the
Mortality rate remains robust.
Tests were also done on unsealed asphalt lots. There was a very slight mortality with
the water fleas, and none for the fathead minnows.
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Are coal tar PAH emissions during drying significant? YES. This covers ONLY 48 hours
of drying, yet when the total amount of coal tar used was figured, the total PAHs
emitted were more than all vehicle emissions in the year 2010, the year that
calculations were made.
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Also, from the National Toxicology Program’s 13th Report on Carcinogens:
Known To Be Human Carcinogens
Coal Tars and Coal-Tar Pitches
Reasonably Anticipated To Be Human Carcinogens
15 PAHs
Note that naphthalene is not currently listed as a known or reasonably anticipated
carcinogenic PAH; however, the National Toxicology Program has concluded that
there is clear evidence of carcinogenic activity in animals (NTP, 2001b).
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So what do we do?
There are alternatives to coal tar sealants. Some are are about the same
cost, about the same durability, and so on.
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Asphalt Emulsion sealants are primary substitutes
Similar Cost, maybe a few dollars more
Similar Durability (some sources say 2-3 yrs for asphalt and 3-4 yrs for
coal tar
BUT -- Asphalt PAH content is 1/1000th that of Coal Tar
There are some other limitations like asphalt emulsions cannot be
applied in cooler weather.
Other products like latex-based sealants are more expensive.
But the benefit of not putting down the coal tar & its PAHs is the big pay
off – eliminate the risk.
Also:
Sealants provide little protection – they mainly provide a restored
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appearance.
So property owners do not have to use sealants at all, and when BACOG
polled our own governments this past year, we found that several were
not using sealants.
As an option, especially when asphalt pavement has deteriorated, a
property owner can replace the pavement with concrete or even better
for the environment = permeable pavers.
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There is good news in all this:
Many big retailers have stopped carrying the product on their shelves, including:
Home Depot, Lowes, Menard’s.
But it is not outlawed, and we researched retailers, and found it at Blain’s Farm &
Fleet in Woodstock and on-line at True Value, for example.
The fact that it’s not widely available at the big retailers tells us that our primary
audience is not the do-it-yourselfer, in our communities anyway, but those who use
contractors.
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Statewide bans would be best, of course.
Going to need to adjust these bans to address high PAH products that are not coal tar
as this industry changes.
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What about Illinois?
Why did it fail? The bill sponsor said:
• Need education for legislators that it’s a real issue
• Not enough public awareness – so not much/enough pressure on legislators
• Pressure from the industry to NOT do this
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When we consider options, we believe we need to focus on local action.
You can regulate residents – but we are in a climate of people wanting
less regulation.
So need balance of property owner responsibility, awareness, etc and
maybe some restrictions.
And we know we will make a bigger impact by restricting the commercial
applicators instead of the DIY homeowners, at least in this area (BACOG).
A ban could be adopted by a municipality for example. A ban could place
responsibility on both the homeowner AND the contractor.
Some bans require all sealcoat contractors to register with the
municipality, and sign a “certification” that they will NOT use coal tar
products within the municipality. If they are found using coal tar, they
receive a fine. The homeowner can also receive a fine under some bans.
Compliance with a local ban involves inspection -- that would include
requiring a contractor to produce their Materials Data Safety Sheet that
describes all ingredients in the sealant and the CAS#.
There could also be testing in the field that involves a solvent in a small
bottle that turns dark if PAHs are in the sealcoat – this requires staff to go
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out after a product is applied, do a scraping, and run the test.
So also consider that governments may have limitations on their own
resources that will limit their ability to enforce a local ban.
With no or small staffs, the municipality would need to contract for
inspections = expensive.
Compliance if coal tar is found may involve removing the sealant
completely = another expensive project.
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Some municipalities and counties are adopting bans. Winnetka, Lake in
the Hills, Spring Grove – near us.
South Barrington enacted a ban in 2012, and this summer adopted additional
provisions for enforcement.
Village of North Barrington is considering a ban as well.
Several of BACOG’s members have enacted policies to not use coal tar products
already, so the support for this action is growing steadily through BACOG’s education
efforts.
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Another innovation:
IGAs or Resolutions among governments, who are committing to not use coal tar
sealants on their own municipal and township properties -- and maybe other
governmental entities that own property too (like park districts, school districts)
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Public education is important.
BACOG has started a campaign with its Water Resources Committee to try to reach
homeowners, to make sure they know the dangers to people, children and even their
pets.
And so they understand why their municipality might want to adopt a ban.
We have developed: Fact sheet, newsletter articles, contractor piece for homeowners, full
color brochure.
Getting coal tar and PAHs out of the environment is about protecting the public
health and a cleaner environment.
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