Zinc contamination of storm water...source?
    Topic posted April 13, 2010 by smendumContributor, last edited January 19, 2012 
    2145 Views, 5 Comments
    Zinc contamination of storm water...source?

    I wanted to get an idea of your experience in this area. We are looking at a site that has now had a number of consecutive quarters of storm water samples with elevated zinc. There are no obvious external storm water exposures and the operating entity at the site does not use zinc or materials in which zinc is a component.

    My feeling is that the zinc may be coming from galvanized corrugated steel roof and wall panels, which are not painted and have been in place for some time. I have seen this issue in the EU over the years, but this is a first for me where it is becoming a regulatory headache here in the US.

    What do you think? Could the galvanized steel be the source? I'd appreciate your input and advice...Thanks in advance.



    • CLCraig

      Elevated zinc concentrations is commonly found in groundwater monitoring wells made of glavenized steell when tehy have gone for a long time without being sampled.  It would not surprise me if rainfall has fbegun to leach the zinc from galvanized roof components.

    • RobE

      Zinc is a fairly common constituent in urban/industrial storm water runoff.  Some common sources include galvanized roofing material (as you point out).  Also, tire dust and motor oil / hydraulic oil.  Here is a useful link:

    • Tom Speight

      Yeah, galvanized roofing is a common culprit-- the galvanic process fuses a layer of zinc to the metal surface as a protective coating.  Zinc ingots used in the process also usually contain about 1% or so by weight of lead, so look for lead too.

      If you have a rubber products manufacturing use, it may also come from that-- zinc is a big byproduct of some of the rubber processes like vulcanization.

    • Stones

      Tire dust, yes, pretty common.  Zinc, bad for the fishies.  Stormwater treatment systems for dealing with zinc are available.  My company is putting a system in at a trucking company facility where the zinc source is primarily from tires.