HYDROGEOLOGY OF THE LOWER MISSISSIPPI VALLEY AS RELATED TO THE WORK OF FISK,HAROLD,N

Principally concerned with the evolution of the Lower Mississippi Vall ey (LMV), the Fisk (1944) investigation provided one of the first desc riptions of the stratigraphic and structural framework of the region. The study provided new data for hydrogeological studies by state and f ederal agencies. The Fisk report was the basic reference for one of th e earliest studies of a complex regional aquifer system - the Mississi ppi embayment project. Begun by the US Geological Survey (USGS) in 195 7, the study covered the Lower Mississippi Region north of the 32nd pa rallel. A study of ground water in the alluvium in the upper and centr al part of the region was completed by the US Army Corps of Engineers in 1964 (Krinitzsky and Wire, 1964). A study, completed in 1970 by the USGS for the Mississippi River Commission (MRC) as part of a plan to export water to west Texas and New Mexico, assessed the availability o f fresh ground water in the entire Lower Mississippi Region (Boswell, 1970). Some results of this study were included in Appendix C of the L ower Mississippi Region Comprehensive Study Coordinating Committee (19 74). During the last 20 years, hundreds of hydrogeological studies hav e been made in the region, and several computer models of aquifer syst ems have evolved. The USGS Regional Aquifer System Analysis (RASA) Pro gram included the region in two models: the Mississippi embayment aqui fer system and the Gulf Coast regional aquifer system. RASA models est ablish a geological, hydrological, and geochemical database for use in regional and local development and in the management of ground-water resources. The Mississippi embayment study unit of the National Water Quality Assessment Program is currently underway. Continuing hydrogeol ogical studies are needed to assess in more detail the hydrogeology of all aquifers in the region. The vast alluvial aquifer system is of sp ecial importance because it is the largest ground-water reservoir in t he region, and it is the most susceptible to contamination and the eff ects of mismanagement.