Minnesota Paving Way for Safer Seal Coats on Asphalt

Sealed Asphalt Play Area Common Throughout the US

The following article is a good summary of the excellent work currently going on in Minnesota from the Minnesota Pollution Control Agency’s Waterfront Bulletin for March 2013:

In spite of recent wintry weather, summer maintenance season is fast approaching for driveways and other paved surfaces. As it does, Minnesota is leading a growing movement away from the use of coal tar-based sealcoats on asphalt pavement because of concerns over polycyclic aromatic hydrocarbons or PAHs.

The cancer hazards of PAHs are well-known, and researchers are studying other possible health hazards. Scientists around the United States, including those at the MPCA, have established that coal tar sealcoats are a major active source of urban PAH contamination. As the sealcoat breaks down, PAH-laden dust is tracked or blown into houses where it is easily breathed or ingested, or it washes into streams and ponds where it contaminates sediments and harms aquatic life.

Concerns over health impacts, along with the public and private cost of cleaning out highly-contaminated sediments in stormwater ponds, have been growing for several years. One result has been bans on coal tar sealcoat use in 28 Minnesota cities, several local governments and watershed districts in other states, and the state of Washington.

Another result was a grant to MPCA from U.S. EPA’s Great Lakes Restoration Initiative to promote the phase-out of coal tar sealcoat use in Minnesota and other Great Lakes jurisdictions. With that grant, MPCA has consulted technical experts to confirm that sealcoats do indeed play a role in preserving pavement, and is reaching out to many Minnesota audiences (residents, parking lot owners, suppliers or contractors) to end use of coal tar. Successful outreach tools are passed on to other Great Lakes states, cities and community groups.

Safer alternatives are available:
Low-PAH products that are asphalt-based, equally protective and similar in cost; and
No-PAH products that are acrylic or soy oil-based.

Visit the MPCA’s Coal Tar/PAH Reduction Project webpage for more information, or contact MPCA’s Al Innes for more information at 651-757-2457.