Read the City's water quality protection publications.
The following list of products* contain no coal tar according to the product labels.
*Sealant product availability is changing rapidly. There may be other sealant products available that do not contain coal tar so please read labels carefully. Listing of a specific product trade name does not constitute an endorsement of its use.
"This is a list of alternative pavement sealant products to assist in compliance with Austin's Coal Tar Ban Ordinance. The Watershed Protection and Development Review Department does not advocate or recommend any one company's product or service and is not responsible for their performance. This department encourages persons to be fully informed of all aspects of the product chosen including human health related issues. We have included links to each product on this list to facilitate your search. The list was compiled from various advertisement listings and from contacts with company representatives and may not represent all the pavement sealant product or service companies that exist."
The City of Austin amended its Code to ban the use and sale of pavement sealants containing coal tar within the City’s planning jurisdiction (full purpose city limits and ETJ). The one exception is that the sealant may be sold if the intended application area is outside the City’s ETJ. The Austin ban was effective January 1, 2006.
Basis for the Ban
Field staff (inspectors, investigators, biologists, etc.) for the Watershed Protection Department watch for sealant applications in progress and freshly sealed parking lots as they drive throughout the city on their other job duties. Whenever new sealant is found, it is screened for the presence of coal tar. Enforcement action is taken when coal tar-based pavement sealant is found applied after the ban was initiated. That enforcement action through municipal court typically involves remediation of the applied sealant. The requirement for remediation is full removal of the coal tar sealant. Besides remediation, legal action can include fines and jail time.
The city produces and disseminates educational materials to producers, applicators, buyers, and to the general public through various means. City staff also periodically checks distributors to monitor product on their shelves.
Citizens may call in suspected coal tar application to the City’s 24-Hour Pollution Hotline at 512-974-2550.
Coal tar based sealants should not be disposed of as regular garbage. Austin and Travis County residents may dispose of Household quantities of coal tar based products at the City of Austin’s Household Hazardous Waste Facility. The facility is located at 2514 Business Center Drive and is open on Tuesdays and Wednesdays from noon to 7 p.m. Businesses requiring information regarding the disposal of coal tar based products may call 512-974-3443.
If you have specific questions concerning the regulations governing the disposal of coal tar containing wastes, please contact the Municipal Solid Waste Permits Section of the Texas Commission on Environmental Quality at (512) 239-2334.
When a violation of the Coal Tar Ban Ordinance occurs, the City of Austin requires removal of the coal tar sealant. One of the most effective ways to meet this requirement is by a process called ‘shot-blasting’. Shot-blasting uses small steel beads or “shot”, and a blasting machine, to remove the top layer or layers of sealant. Blasting machines come in two different styles, walk behind (self-propelled or push) and ride-on, with varying blasting widths ranging from 8” to 48”.
The City of Austin requires that shot-blasting machines have a dust collection system (bag or cartridge filters) that minimizes or eliminates air-born dust particles containing harmful PAH’s from contaminating nearby soils, lakes or streams. The removed sealant should be properly contained on the site. Depending on the size of the removal project, some containment options may be bagging the waste in heavy-duty black trash bags or using a roll-off dumpster. Roll-off dumpsters should be properly covered with tarps or plastic sheeting to prevent runoff should precipitation occur. Once the project is completed the generated coal tar waste should be properly disposed of (See “Coal Tar Product Disposal” under the FAQ section)
Property and business owners should ensure that their contractor is properly licensed and bonded and will use the correct removal and disposal methods.
Listed below are contractors known to provide shot-blasting services for the removal of coal tar-based sealants. There may be other contractors that can perform the work. Contractors that are interested in being added to this list may email Christopher Miller to begin the process.
This list is compiled from various listings and company contacts and may not represent all shot-blasting companies that service the Austin area. The Watershed Protection Department does not endorse company products or services and is not responsible for their performance.
Are there PAH concentrations of concern in asphalt-based pavement sealants?
Coal tar and asphalt have different molecular structures stemming from their origins: coal tar is a byproduct of the production of coke from coal and asphalt is derived from the refining of crude petroleum. Product analyses by the City of Austin indicates that coal tar sealcoat products have median concentrations of total PAHs about 70 times higher than concentrations in asphalt-based sealcoat products.
During our annual surveys of stream sediment chemistry, concentrations of Total PAHs (the sum of 16 compounds) generally range from <1mg/kg to over 200 over the past 15 years (Fig. 1). A screening value of 23 mg/kg is used as a threshold, above which, aquatic life use is expected to be negatively effected (Probably Effects Concentration, or PEC), and most of our data falls below this value. However there are a number of locations that have exceeded this value one or more times, and we are looking at these sites carefully for temporal trends and potential best practices that will address the source of PAHs to these sites.
Figure 1: Box plot of total PAH (mg/Kg) collected in EII sampling from 1996-2010. Black diamonds represent means, notched lines represent medians, and small circles represent outliers.
The City of Austin continually seeks ways to educate producers, applicators, buyers and the general public about coal tar and the coal tar ban. City of Austin staff:
By removing this potent source of PAHs to our environment, we are reducing PAHs in our streams. A United States Geological Survey (USGS) study conducted in 2014 showed a 58% reduction in PAH’s in lake sediment from Lady Bird Lake.
Vehicle tires abrade parking lot sealcoat into small particles. These small particles are washed off parking lots by precipitation and into storm sewers and streams. Sealcoat “wear and tear” is visible in high traffic areas within a few months after application. Sealcoat manufacturers recommend reapplication every 2 to 3 years.
Besides urban runoff as a pathway, PAH can originate from atmospheric fallout of particulates from naturally occurring combustion sources like forest fires or from fossil fuel combustion - incomplete burning of carbon-containing materials like oil, wood, garbage, and coal. Automobile exhaust and industrial emissions are additional sources. They contain high levels of PAHs. More PAHs form when materials burn at low temperatures such as in wood fires and cigarettes than in high-temperature furnaces.
Many useful products such as mothballs, blacktop, and creosote wood preservatives contain PAHs. They are also found at low concentrations in some special purpose skin creams and anti-dandruff shampoos that contain coal tars.
The detrimental effects of PAHs aquatic ecosystems are well documented. Examples:
The City of Austin has conducted a range of laboratory and field experiments which documented the negative effect that PAHs from coal tar sealants have on benthic invertebrates that live in our streams. This work was a primary support and motivator for the ban of coal tar sealants in Austin
Considering Seal Coating your Parking Lot?
The following recommendations will assist you in getting a better job that lasts longer while protecting the environment
Choose the Right Applicator
Choose the Right Product
Ensure a Good Application
For additional information of the recommendations provided, please call 512-974-2550.
There are a variety of forces that wear sealant off of lots and driveways, but the abrasion of tires is probably the dominant one. In temperate northern climates, snow plows are probably another major factor. The City of Austin did a photographic coal tar sealant wear study, finding that drive areas wear at about 5% per year, and parking areas at about 1.5%, with an average of about 2.5% per year. A study in 2010 by the University of New Hampshire found that export of PAHs off of parking lots was much greater in the first three months (1357ug/L) than in the two years following application (17-116 ug/L), although elevated concentrations (52ug/L) of PAH from coal tar lots can persist for at least 5 years (Selbig, 2005).
Currently, the use of coal tar-based pavement sealant is not federally regulated. In 1992, the U.S. environmental Protection Agency 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 are products that contain recycled coal tar and, therefore, are not regulated.
|District of Columbia||Washington|
|Minnesota (29 Citywide Bans)||Albertville, Buffalo, Cannon Falls, Centerville, Circle Pines, Eden Prairie, Edina, Elk River, Falcon Heights, Golden Valley, Hutchinson, Inver Grove Heights, Little Canada, Maplewood, Medina, Minneapolis, Newport, New Hope, Oakdale, Prior Lake, Rosemount, Roseville, Shoreview, Shorewood, Vadnais Heights, Waconia, West St. Paul, White Bear Lake, Woodland|
|New York||Suffolk County|
|Texas||Austin, Bee Cave , Edwards Aquifer: Comal and Hays Counties|