Minnesota's Coal Tar Sealant Ban: What Homeowners Need to Know

What Happened

Minneapolis and St. Paul banned the use of coal tar-based pavement sealants. The reason: coal tar sealers contain high concentrations of polycyclic aromatic hydrocarbons (PAHs), which are toxic compounds that wash into stormwater, contaminate lakes and streams, and accumulate in sediment where they harm aquatic ecosystems.

The USGS documented that parking lots sealed with coal tar had PAH concentrations 65 times higher than those sealed with asphalt-based products. In a state with over 10,000 lakes, this isn't a trivial environmental concern.

Where the Ban Applies

Currently, the ban is enforceable in Minneapolis and St. Paul. However, several other Minnesota cities are considering similar ordinances, and the trend is clear: coal tar is on its way out statewide. Washington state, Washington D.C., and multiple counties across the country have already enacted bans.

Why Asphalt Emulsion Is Actually Better

Here's the part the coal tar industry doesn't want you to hear: polymer-modified asphalt emulsion sealer performs better than coal tar in Minnesota's climate. Here's why:

• Flexibility: Asphalt emulsion has greater elasticity than coal tar, meaning it flexes with freeze-thaw cycling rather than cracking. In a state with 42–60 inch frost depths, this is critical.
• Adhesion: Asphalt emulsion bonds chemically to the existing asphalt surface. Coal tar sits on top as a coating. In Minnesota's plow-and-salt winter maintenance regime, adhesion matters.
• UV Resistance: Modern polymer-modified emulsions match coal tar's UV blocking performance without the environmental toxicity.
• Odor and Safety: Coal tar produces noxious fumes during application that are harmful to workers and neighbors. Asphalt emulsion has minimal odor.

What This Means For Your Driveway

If you're anywhere in Minnesota, we recommend asphalt emulsion regardless of whether your city has enacted a ban. It's the better product for our climate, it's environmentally responsible, and it's the direction the entire industry is moving. We exclusively use polymer-modified asphalt emulsion with silica sand additive — no coal tar, period.