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Nitrate Contamination of Groundwater

Ground Water Hydrology

  1. Ann Azadpour-Keeley1,
  2. Jack Keeley2

Published Online: 15 APR 2005

DOI: 10.1002/047147844X.gw761

Water Encyclopedia

Water Encyclopedia

How to Cite

Azadpour-Keeley, A. and Keeley, J. 2005. Nitrate Contamination of Groundwater. Water Encyclopedia. 5:322–323.

Author Information

  1. 1

    National Risk Management Research Laboratory, ORD, U.S. EPA

  2. 2

    Dynamac Corporation, Ada, Oklahoma

Publication History

  1. Published Online: 15 APR 2005


Groundwater supplies drinking water for half of the people in the country and represents the total water supply for many of the western states. Numerous contaminants are anthropogenic, including petroleum products, chlorinated solvents, and pesticides, but nitrate contamination can be either natural or man-made and is one of the most common chemical contaminants of groundwater. Nitrate levels in uncontaminated groundwater are generally less than 2 mg/L, but levels have been increasing during the past five to six decades in areas where contamination has occurred.


  • nitrate;
  • groundwater;
  • nitrogen cycle;
  • fertilizer;
  • nutrients