Abstract:
All naturally occurring water contains some impurities. Water is considered polluted when the presence of impurities is sufficient to limit its use for a given domestic and/or industrial purpose. As defined by Fried "Pollution is a modification of the physical, chemical and biological properties of water, restricting or preventing its use in the various applications where it normally plays a part". According to Freeze and Cherry all solutes introduced into the hydrologic environment as a result of man's activity are referred to as 'Contaminants', regardless of whether or not the concentrations reach levels that cause significant degradation of water quality. The term 'Pollution' is reserved for situations where contaminant concentrations attain levels that are considered to be objectionable.
