I began studying transport hydrology during my master's research through the use of fluorescent dyes in the karst around Springfield, Missouri. This involved injecting several dyes into sinking streams and sinkholes and measuring their arrival time and quantity using automatic samplers at nearby springs. From these dye traces I was able to determine the local near-surface flow regime and its relation to a newly forming sinkhole by a major highway funded by fellowship with the Missouri Department of Transportation.
At the Minnesota Department of Health I continued to pursue flow transport but with more focus on numerical modeling to delineate wellhead capture zones for municipal drinking water systems. This modeling was largely accomplished using the multi-layer analytical element modeling code MLAEM developed by Otto Strack, the stochastic analytical element code Oneka by R. Barnes, and the USGS's MODFLOW.
In addition to wellhead protection I was involved in several larger projects to help municipalities who have encountered issues with water quality or quantity to locate new potential water sources. Using information from the state well database, water quality sampling, geologic maps, and MODFLOW models, we were able to successfully identify areas for the water operators and well drillers to explore for productive new sources.
While at Temple University I have continued to use groundwater flow modeling to address questions related to karst aquifer hydrology. In particular I have been using the finite-element flow modeling code FEFLOW to study how heat and mass are transported in karst conduits. One study site (modeled below) is a conduit which connects a sinking stream to a spring. There I used temperature loggers and high-frequency dye tracing to reproduce possible conduit geometries and conduit-matrix interactions which produce matches between observed and modeled results.