Coal Tar Pavement Sealant Bans Discussed at Stormwater Summit

(Crystal A. Proxmire, Nov. 5, 2017)

Southfield, MI – In Oakland County only two municipalities ban coal-tar based pavement sealants – Wolverine Lake and West Bloomfield Township.

Eric Diesing of the Clinton River Watershed Council and Rebecca Esselman of Huron River Watershed Council hope to change that.  And at the recent 2017 Regional Stormwater Summit they shared the reasons why.

They shared research from several Universities and groups that show environmental and health consequences from coal-tar sealants.  A safer alternative is asphalt-based.

“Coal-tar based sealants are mainly used east of the Rockies because it’s a byproduct of the steel industry,” Diesing said.  He explained that when cities, townships and villages institute bans they limit the concentration of Polycyclic Aromatic Hydrocarbons to 1,000 ppm. Most coal-tar sealants have a concentration of 50,000 ppm.

Chemicals in the sealants get carried along with Stormwater and can impact waterways and soil. They can also get into humans through their skin.  In contaminated waters, scientists have found inset death, fish deformation, organ abnormalities, fish mortality and reduced heart size in amphibians, he said.  In humans it can cause cancer, birth defects and mutations in DNA.

Esselman talked about legislative efforts to ban coal tar sealants across the county, starting with Austin, TX in 2005. “Since that time they’ve seen a 58% decline in PAHs,” she said.

As a result of this and other bans, several major chains including Ace, Lowes and Home Depot have pulled coal-based tar products from their shelves.

In 2009 the first attempt at a ban in Michigan was introduced by Stat Representative Rebekah Warren, though it did not get a hearing.

In 2013 an organization that helped promote a ban in Minnesota (Freshwater Future) decided to expand their efforts to Michigan.

In Dec. 2015 Van Burean Township passed the first ban in Michigan. Other communities include Wolverine Lake, West Bloomfield Township, Almont, Ann Arbor, Ann Arbor Towship, Clark Township, Byron Center, Albert Township, Erie Township White Lake Township, Powell Township, St. Charles, and the Village of Shepherd.

Both Clinton River Watershed Council and Huron River Watershed Council, as well as others through the state, are looking for ways to encourage local bans.  “The ideal here is to get a state level ban instead of all these local level bans,” Esselman said.  Though it has been introduced in Lansing several times without any movement.

One challenge is that some bans simply list coal-tar sealant, and “in response to bans, the industry is developing non-coal alternatives that are still high in PAH,” she said.

Some aspects that communities have included in bans have been stipulating a 0.1% thresheld of PAH in any sealant product used, require registration before sealing work can be done, and having a significant penalty associated with its use.

Some communities have bans or policies that state it will not be used on public property, while others ban its use completely.

The website www.CoalTarFreeAmerica.com gives more information about municipal bans, studies on the impacts of its use, and more.

Learn more about Clinton River Watershed or Huron River Watershed.