Application of aquifer tests and sedimentological concepts to characterize the hydrological properties of a fluvial deposit

Abstract

This dissertation focuses on the interpretation and evaluation of pump and tracer tests from a heterogeneous unconfined aquifer in Columbus, Mississippi, USA. A prominent feature of the aquifer is a paleochannel that crosses through two test sites. Key aspects related to the pumping test analysis are large-scale variations in the transmissivity field, preferential flow paths through high-K deposits/lenses and well screens, locally confined to unconfined aquifer conditions, and positive skin effects. Analysis of field data shows a fundamental connection among sedimentological features, log(K) data, large-scale tracer test results, large-scale pumping test results, and ambient groundwater flow patterns. By detailing the characterization of the test site, paradigms different from those traditionally used for homogeneous aquifers are established to guide field tests and remediation efforts in similarly heterogeneous fluvial aquifers.