By Valerie J. Kelly, Richard P. Hooper, Brent T. Aulenbach, and Mary Janet
Reston, Virginia: 2001
U.S. Department of the Interior | Gale Norton, Secretary |
U.S. Geological Survey | Charles G. Groat, Director |
For further information contact:
Office of Water Quality U.S. Geological Survey 412 National Center Reston, Virginia 20192 Internet: http://water.usgs.gov/nasqan |
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