Minnesota coal tar sealant phase-out legislation passes

In a major victory for water quality and public health, the Minnesota Legislature passed a bill phasing out the use of coal tar sealants in Minnesota. Effective January 1st 2014, no person shall apply coal tar sealant products on asphalt-pavement surfaces, nor sell a coal tar sealant product that is formulated or marketed for application on asphalt-paved surfaces.

This is a big win for FMR and the Mississippi River. This issue was recently highlighted in the State of the River Report, and was one of FMRs priority policy recommendations to the State Legislature in our Mississippi River Policy Guide.

Background: A lesson in unintended consequences

Coal tar sealants (refined coal tar pitch emulsion) are one of several types of products used to seal asphalt surfaces such as driveways and parking lots in Minnesota. About 85 million gallons are applied in the United States each year.

Unfortunately, these products dont remain on the pavement indefinitely. Over time, these sealants wear down and are carried by wind and rain into the environment, where they pose a range of potential risks to communities.

Coal tar sealants can contain as much as 33% Polycyclic Aromatic Hydrocarbons (PAHs) by weight. PAHs are a family of compounds that pose environmental and public health risks that have been found to be accumulating in stormwater ponds and freshwater lakes.

Fiscal Impact

Stormwater pond sediments contaminated with PAHs are considered hazardous waste. As cities conduct routine maintenance on stormwater ponds (cleaning out excess sediment as it builds up over time), the costs on disposing this contaminated sediments skyrockets. The Minnesota Pollution Control Agency estimates that clean up costs for the stormwater ponds most contaminated with PAH runoff could approach $5 billion in the metro area alone.

This cost will only grow over time, and is a major reason why many local governments support statewide action on coal tar sealants. A recent Star Tribune article highlights the staggering financial risks facing the Twin Cities metro area due to PAH-contaminated stormwater ponds.

Human Health

Coal tar is listed as a Group 1 carcinogen, and presents a known cancer risk for humans. The PAHs in coal tar are also concern, as prolonged exposure to PAHs poses a cancer risk for humans as well.

PAHs from coal tar end up in our homes and businesses, exposing local residents to unintended health risks. Recent research indicates that residences with coal-tar-sealed parking lots have 25-times more PAHs in house dust than residences with unsealed parking lots.

Environmental Health

PAHs also present a variety of risks to aquatic life and health. Fish exposed to PAHs have been found to exhibit tumors, organ abnormalities, fin erosion, cataracts, and immune system impairments. Macroinvertebrates exhibit inhibited reproduction, delayed emergence, sediment avoidance, and mortality. Amphibians exhibit stunted growth, delayed development, organ problems, difficulty swimming, and mortality.

In addition, excessive clean up costs for contaminated stormwater pond sediment may push cities to forgo pond maintenance, resulting in decreased pond performance and increased pollution and flooding in surface waters.

Alternative Products

Asphalt-based sealants are the most popular alternative to coal tar sealants. While asphalt-based sealants do contain small amounts of PAHs, PAH concentrations in coal tar sealants can be 1000-times higher than concentrations in asphalt-based sealant alternatives.

2009 Legislation

2009 legislation restricted state agencies from purchasing coal tar sealants, and provided funds for notification and the development of a pond inventory schedule, BMPs, and model ordinances. Funds were also made available to communities for remediation. To date, only 6 communities have accessed these funds, which were exhausted as of September 2012.

2013 Legislation

On May 20th 2013, The Minnesota Legislature followed the lead of Washington State and became the second U.S. State to enact legislation, effective January 1st 2014, to:

  • Ban the application of coal tar sealants on asphalt-paved surfaces in Minnesota; and
  • Ban the sale of coal tar sealants for use on asphalt-paved surfaces in Minnesota

Thank you to Minnesota legislators for taking storm leadership on coal tar sealants!

For more information on coal tar sealants, PAHs, and recent water quality legislation in Minnesota, please contact FMRs Watershed Program Director Trevor Russell.

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