DATA COMPILATION OF WATER CHEMISTRY AND GROUNDWATER LEVELS FOR THE MISSISSIPPI EMBAYMENT IN AR, TN, MS, AND LA

The Mississippi Embayment Regional Ground Water Study group located at Arkansas State University compiled and organized the available water chemistry and groundwater level data from the USGS groundwater monitoring database for the Mississippi Embayment in Arkansas, Tennessee, Louisiana, and Mississippi. Over 200 MB data have been examined for accuracy. Only the evaluated data that passed these quality tests have been included in this compilation.

Across state lines, the same aquifers and geologic units often have different regional names. For uniformity, consistent names for the geologic and hydrogeologic units are used. The Mississippi River Valley Alluvial Aquifer (ALVM) is the upper unconfined aquifer. The subsequent confined aquifers are the Upper, Middle, and Lower Claiborne Aquifers. The compilation does not include the Middle and Lower Wilcox aquifers or the McNairy-Nacatoch Aquifer.

The first level divides the data by states: AR, TN, MS, and LA. At this stage, the original data have not been examined for quality. The second level is composed of quality assessed data by hydrogeologic unit (ALVM, Upper Claiborne, Middle Claiborne, and Lower Claiborne). Each file follows the same structure to minimize confusion.

The potential number of chemical, geographical, and physical parameters for each well is ~690; however, each groundwater well is typically characterized by a maximum of 20 parameters. It is uncommon to have organic, inorganic geochemistry, hydrogeology (depths, water level, etc.), and geochemical monitoring data. The most constantly recorded chemical data are chloride and electrical conductivity.