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Toxic Sealers: An Origin and Redemption Story


Imagine for a moment that you woke up to a scathing, critical expose in the local paper about your work. Like the entire front page, headlines, and a whole lot of the front section. Even the political cartoon mocked your work.


Add to this that your job was taking care of one of the most important places in your community. You know, like a place that everyone takes pride in and that your city is known for. And now it appears, according to the paper, your team’s “negligence” has put future access to that facility in jeopardy.


That’s the bleak situation City of Austin staff found themselves in January 2003.


For more than 100 years Barton Springs has been known as the “Soul of Austin” because residents have long sought relief from tortuous summer heat in the refreshing, 68 to 70 degree waters in this spring-fed pool.


The local paper, the Austin-American Statesman had consulted with leading national experts about the contamination of polycyclic aromatic hydrocarbons (PAHs) which were found in and near Barton Springs Pool. The headline screamed “Toxic Waters”! Experts said the only way to get such high readings were from hazardous waste and that the source must be an old dump nearby.


The city manager closed the Pool for 90 days to investigate.


In August of the previous year, a city staff member theorized that the source was coal tar-containing pavement sealers – even though there was very little supporting research. Pavement sealers are a black liquid applied to parking lots and driveways for beautification and longevity.


Some city colleagues scoffed at the theory. The US Geological Survey, who had routinely consulted with the City on water issues, believed there must be an error in the lab testing because of the high levels of PAHs.


However as staff began testing parking lots all over the City, high PAHs were found everywhere and associated with coal tar pavement sealers.


Soil borings were taken to find the old landfill with high levels of PAH. None was found.


Local, state and federal experts examined the data at the Pool and deemed it safe.


The State of Texas weighed in and said the City ought to clean up the small creek near the Pool that had been contaminated from the runoff from coal tar pavement sealers.


The Pool reopened ironically just before Easter to a jubilant community on April 19, 2003. What was possibly lost was found again. What might have been dead was alive and well. Admission was free to all Austinites for the day and month following. “Super Fun” Site fans were distributed. Speeches were given. There was diving for Easter eggs for the kids and the mayor dove into the Pool with his street clothes on and joined the city manager!

The work of city staff continued on this topic for the next two years. They spoke with the EPA, industry leaders and asked local applicators to voluntarily substitute non-toxic products for the coal tar containing ones.


In June of 2005 a joint study between the City and the USGS was published in a peer-reviewed journal. The study demonstrated the mobility of cured coal tar pavement sealcoats during rain events. It was the first study of its kind of this unrecognized source of PAH pollution.


By November that year the City of Austin passed the nation’s first coal tar sealer ban. A gift to the nation for a possible coal tar free future!


Photo credit: Spawnzilla: https://commons.wikimedia.org/wiki/User:Spawnzilla

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