I wanted to take the opportunity to thank the University of Michigan for quietly sticking with their commitment to be free of coal tar sealants. A recent report chronicles their efforts that are part of their “Good Housekeeping” provisions of their NPDES (National Pollution Discharge Elimination System) stormwater permit. They reviewed over 150 construction plans for conformity with this standard. The report goes on to
University projects that involve sealing parking lot surfaces incorporate the NPDES permit language prohibiting coal tar emulsions to seal asphalt surfaces.
Coal Tar Asphalt sealants were not used on the UMD (Dearborn) campus.
What was the origin of this effort? I don’t know. A statewide ban was introduced in Michigan’s legislature by Ann Arbor Senator Rebekah Warren in 2009 after the University of Michigan’s prohibition went into effect.
Whatever the source, the Michigan story is an interesting one (as far as state permits go). Last year I got an anonymous tip presumably from a State of Michigan government employee about a rash of coal tar sealant prohibitions throughout the state in 2008. I doubled checked that source which led to my understanding that at least 70 stormwater permits throughout Michigan was the provision for the permittee to stop using coal tar sealants. Technically the permits should be referred to as “government use restrictions” because they appear to restrict the use of sealant by the unit of government, but not the jurisdiction that they govern. I have since found these provisions in other NPDES permits around the country. The text of the comment is at the end of this post in italics.
According to several sources, the sealant prohibition was a small part of sweeping changes that many of the communities had real problems with. They challenged this in court and as of now, most Michigan permittees have reverted back to their 2003 permits.
I must confess I don’t know the full story in Michigan, but my gratitude for these efforts continues nonetheless.