st Manaaement Practice United States Environmental Protection Agency Hydrocarbons, and Stormwater Pollution NPDE Minimum Measure Pollution Prevention/Good Housekeeping What Is Coal-Tar Sealcoat? Coal-tar sealcoat is a type of sealant used to maintain and protect driveway and parking lot asphalt pavement. Coal-tar sealcoat typically contains 20 to 35% coal tar pitch, a byproduct of the steel manufacturing industry, which is 50% or more polycyclic aromatic hydrocarbons (PAHs) by weight. Could Coal-Tar Sealcoat Be a Concern for Stormwater? Studies found that PAHs are significantly elevated in stormwater flowing from parking lots and other areas where coal-tar sealcoats were used as compared to stormwater flowing from areas not treated with the sealant. For example, one study found the amount of PAHs in stormwater runoff was 65 times higher from parking lots sealed with coal-tar sealant vs. stormwater from unsealed parking lots. Another study found that coal-tar sealcoat is the largest source of PAHs to urban lakes. PAHs from coal-tar sealcoat may accumulate in the sediment of stormwater ponds, requiring expensive disposal of the dredged PAH-contaminated sediment. PAHs are of concern because of their harmful impacts on humans and the environment. They are persistent organic compounds, and several PAHs are known or probable human carcinogens and toxic to aquatic life. What Are States and Municipalities Doing to Address PAHs from Coal-Tar Sealcoat? Several states and cities have taken action to address PAHs from coal-tar sealcoat. The following are some notable examples: • The city of Austin, Texas banned the sale and use of coal-tar containing pavement sealants in 2005: http://austintexas. gov/department/coal-tar • The District of Columbia banned the sale and use of coal-tar sealcoat in 2009: http://green.dc.gov/coaltarban • In 2009, Minnesota restricted state agencies from purchasing undiluted coal tar-based sealant and directed its Pollution Control Agency to study the environmental effects of coal tar-based sealants and to develop management guidelines: www.pca.state.mn.us/index.php/water/water-types-and- programs/stormwater/municipal-stormwater/restriction-on- coal-tar-based-sealants.html • Washington State banned the sale of coal- tar pavement sealants on January 1, 2012 and banned the use of such sealants after July 1, 2013: https://fortress. wa.gov/ecy/publications/ summarypages/1104021. html Alternatives to Coal-Tar Sealcoat Pavement options such as pervious concrete, permeable asphalt and paver systems do not require sealants. These types of pavements allow for stormwater to naturally infiltrate, resulting in decreased runoff. Office of Water, 4203M www.epa.gov/npdes/pubs/coal-tar.pdf www.epa.gov/npdes/stormwater/menuofbmps EPA833-F-12-004 November 2012 ------- Stormwater Best Management Practice: Coal-Tar Sealcoat, Poly cyclic Aromatic Hydrocarbons, and Stormwater Pol For More Information References For more information you can watch EPA's webinar Stormwater, Coal-Tar Sealcoat and Polycyclic Aromatic Hydrocarbons available at: http://cfpub2.epa.gov/npdes/courseinfo. cfm?program_id=0&outreach_id=645&schedule_id=1169. For information on assessing the toxicity of PAHs in sediment see: www.epa.gov/nheerl/downloadjiles/publications/ PAHESB.pdf from EPA's Office of Research and Development. Additionally, you can visit the USGS webpage on PAHs and coal-tar-based sealcoat: http://tx.usgs.gov/coring/ allthingssealcoat.html. Mahler, B.J.; Van Metre, PC.; Crane, J.L.; Watts, A.W.; Scoggins, M.; Williams, E.S., Coal-tar-based pavement sealcoat and PAHs: Implications for the environment, human health, and Stormwater management. Environ. Sci. Technol., 2012. Van Metre, PC.; Mahler, B.J., Contribution of PAHs from coal-tar pavement sealcoat and other sources to 40 U.S. lakes. Sci. of the Total Environ., 2010, v.409, 334-344. Scoggins, M.; McClintock, N.L.; Gosselink, L; Bryer, P., Occurrence of polycyclic aromatic hydrocarbons below coal-tar-sealed parking lots and effects on stream benthic macroinvertebrate communities. Journal of the North American Benthological Society, 2007, 26(4):694-707. Mahler, B.J.; Van Metre, PC.; Bashara, T.J.; Wilson, J.T.; Johns, D.A., Parking lot sealcoat: An unrecognized source of urban PAHs. Environ. Sci. Technol. 2005, 39, (15), 5560-5566. EPA's Integrated Risk Information System (IRIS): www.epa.gov/IRIS/ ------- |