Coal Tar Sealers are a Net Financial Burden to any Community Including San Antonio

The San Antonio Express News recently ran an editorial by a local coal tar sealant contractor. The claims about science have already been addressed, but a more thorough review of the economics may
be helpful.

For you busy people, here’s the bottom line:

The industry’s economic analysis contains false cost assumptions, false warranty assumptions, exaggerated seasonal effects, overstated economic value and ignores the environmental, legal and human costs as well as paving experts who recommend not using coal tar sealers.

False Pricing Assumptions

This economic analysis assumes that either asphalt sealers cost twice as much as coal tar sealers or they only last half as long. This is a fallacy. The longevity of a sealant job depends more upon the preparation, dilution, and quality of additives and all that adds up to cost. One major national supplier testified in 2014 that the cost of their products asphalt-based and coal tar based were the same as seen in this short video.

We do an annual survey of prices of retail products. This graph demonstrates the correlation of warranty to price. For example a 5 gallon bucket with a 2 year warranty was $18 and that same volume was nearly double the cost, $35 for a ten year warranty. Most savvy consumers know you get what you pay for and this is especially true in the sealcoat industry which has plenty of folks who dilute their product or do poor installations in order to make an extra buck.

False Warranty Assumptions

Mr. Cravin’s calculations assumes that commercial parking lots with a coal tar surface last four years. Check the warranty with any sealcoat supplier and they only warranty the product from failure due to their design with no warranty length stated. In other words, if it works for a season, then it was a good mix design and that is the extent of the warranty.

Industry insiders confirm that the best contractor warranty a commercial sealcoat job will get, no matter what the product, is just one year. I have seen residential driveways with longer warranties, but to assume coal tar somehow lasts twice as long yet no one will warranty that, is just wishful thinking!

Exaggerated Shortened Season

To whine about a shortened season in San Antonio, Texas is laughable when you find dozens of contractors in the northern US and Canada making a good living from sealcoating with only asphalt-based sealers with dramatically less sunshine, warm weather and less humidity.

There are plenty of days in December, January and February in central Texas which are suitable for both coal tar sealer AND asphalt-based products. Therefore the assumption of lost wages and unemployment are false in a ban occurs.

It is true in extremely marginal conditions (humid and near 50 deg F) coal tar sealers (without additional additives) can have a superior cure time BUT at a significant human and environmental cost. For every acre of asphalt coated with coal tar sealers, it creates a toxic surge of polycyclic aromatic hydrocarbons (PAHs) into the air, so great that it would be a reportable toxic air emissions event if it were an industrial site.

True Value Overstated

The value of the industry is overstated. Contractor-grade sealer is available for about $5 per gallon and if installation mirrors the cost of the product that would be about $10 per installed gallon of sealer.

How much is used annually in San Antonio? A good guess, based upon industry figures, would be about 1 gallon per person per year or about 1.5 million gallons per year. It is likely less than that, but is a good number to estimate from. Keep in mind that 1.5 million gallons yields about 500,000 pounds of PAHs per year being spread throughout SA.

Combining the installed cost with the number of gallons used, would mean that the industry in San Antonio is only worth about $15 million dollars per year. How you can have an estimated $14 million dollars in losses in an industry only worth $15 million? It just doesn’t add up.

True Costs Revealed

The State of Minnesota estimated cost for the 3.3 million people in the Minneapolis-St. Paul area to clean up after coal tar sealer contamination was over $1 billion! While the circumstances aren’t exact, it gives a sense of the scale of the costs to clean up. If you attribute that amount to the citizens of San Antonio, it would be about $450 million.

Here’s an example closer to San Antonio. The City of Austin was encouraged by the State of Texas to clean up a small drainage which had been contaminated by coal tar sealers from a single apartment complex near Barton Springs Pool. The cost, complete with workers in moon suits because of the high PAH concentrations, was about $500,000! This was for a single parking lot drainage.

Using this number, the cost to clean up Mr. Cravin’s 300 coal tar sealed properties would be $150 million dollars. All for the privilege of making $15 million dollars in coal tar sealer sales. That doesn’t make sense and destines this product to the history books.

Cancer Costs

This does not include the cost of cancer caused by coal tar sealers which a Baylor toxicologist said affect a large number of Americans. 

Let’s talk about the cost of cancer. According to the American Institute of Cancer Research, the nationwide cost of cancer is $900 billion dollars. The proportional cost, based solely on population, to San Antonio would be $4.5 billion. Wouldn’t the leaders and citizens of San Antonio want to make a significant effort in the battle against this disease? No other ordinance with clear, cost-effective substitutes could affect such change with the stroke of a pen.

Ignores the Experts

The liabilities of using coal tar sealers on commercial parking lots are so great that a guidance manual for commercial properties issued this warning in their hardback book, Guide to Pavement Maintenance:

It also isn’t recommended for the longevity of an asphalt surface by the main proponents of asphalt paving, The Asphalt Institute. It has been found to actually degrade asphalt by allowing moisture to build up between the two materials.

What is the cost of that to the City of San Antonio?


To summarize the industry’s economic analysis contains false cost assumptions, false warranty assumptions, exaggerated seasonal effects, overstated economic value and ignores the environmental, legal and human costs as well as experts who recommend not using coal tar sealers.

So we have an industry worth $15 million in annual local sales yet creates greater than $100 million in damages.

Sounds like a dinosaur which should be put in the express lane to extinction.

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