Preface: Insights from environmental tracers in groundwater systems

Excerpt

Hydrogeology developed into an independent field of scientific study over the course of the twentieth century. In the first part of the century, focus was mostly on resource development from aquifers, which depended primarily on an understanding of aquifer hydraulics through changes in water levels, with less focus on the actual movement of groundwater. By the middle of the century, water-quality interests had led to the development of groundwater geochemistry as a scientific field to understand the character and genesis of the natural constituents in groundwater (Foster 1950; Chebotarev 1955; Hem 1970). The discussion of chemical constituents in groundwater in textbooks continued to take a back seat to that of flow hydraulics, and the focus was either on water-quality concerns or upcoming issues pertaining to the transport of chemical pollutants (Todd 1959; Davis and DeWiest 1966; Freeze and Cherry 1979). The fields of physical and chemical hydrogeology were still separate from a practical standpoint illustrated by the fact that the historical contributions, well through the middle of the century, were most easily divided this way (Freeze and Back 1983; Back and Freeze 1983). …