Sources and Leaching of Nitrate Contamination in Groundwater

Nitrate is an important and widespread contaminant of groundwater and surface water resources. Nitrate formed either by the natural processes (atmospheric fixation, lightning storms) or added through anthropogenic activities (fertilizer applications, septic tanks) enters the hydrosphere with virtual ease. In this article we review various concepts discussing the different sources behind elevated nitrate levels. Moreover, an attempt is also made towards preparing a comprehensive framework to understand the leaching of nitrate in groundwater. This framework would effectively help in understanding the origin and dynamics controlling the fate of nitrate in groundwater, which is vital for managing the associated risks and safeguarding the water supplies.