Revision History for USGS 
  Scientific Investigations Map 3113

  Fred D Tillman

  Concentration of 1,4-Dioxane in Wells Sampled During 
  2002-2009 in the Vicinity of the Tucson International 
  Airport Area Superfund Site, Arizona

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  Added layers to the map PDF that you can turn on and 
  off March 8, 2010

  Posted online February 25, 2010

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