ABSTRACT
Groundwater containing contaminants may need treatment before use to meet its expected quality. Geochemical reactions and microbial chemical processes also change groundwater quality. The economic significance of the underground injection control program is that the governments give the right of discharge to waste producers through access to deep geologic formations for the largest volume of controlled waste disposal. Watershed or river basin management has emerged as an integrative approach to improve water quality with regard to ground and surface waters, their interaction and managing contaminant sources affecting both, within the catchment. The natural capital of the subsurface portion of the ecosystem can function to provide some treatment for chemical and pathogens. Treatment of water to facilitate its use as household or community drinking water is the subject of much research and industry. Central water supply treatment providing water to a community of known and accepted quality has a long history.
