ABSTRACT
This chapter summarizes selected illustrations of nitrate pollution of groundwater, particularly as a consequence of agricultural usage of fertilizers or land disposal of domestic wastewaters. It demonstrates the widespread problem of groundwater pollution by nitrates. The chapter identifies the influence of various climatological and hydrogeological factors, fertilizer application practices, and subsurface transformation and transport and fate processes on resultant nitrate concentrations in groundwater. The major sources of nitrate in California groundwaters used as water supplies include leachate produced from agricultural activities and animal and poultry wastes, individual septic tank systems, effluent from wastewater treatment plants, and municipal and industrial runoff. A number of factors and practices can influence the nitrate concentration in groundwater. Several factors and practices influence nitrates in groundwater and nitrate variations with soil depth. The chapter provides a review of 56 references related to illustrations of nitrate pollution in groundwater.
