Robert L. Runkel spends much of his time researching STREAMS, Hydrology, Hyporheic zone, Meltwater and Transient storage. His STREAMS study integrates concerns from other disciplines, such as Diel vertical migration, Estimator and Parallel computing. His Hydrology research includes themes of Inflow and Dispersion. In his study, which falls under the umbrella issue of Inflow, Acid mine drainage is strongly linked to Bedrock. His Transient storage research is multidisciplinary, incorporating perspectives in Exchange coefficient, Soil science and Surface water. The study incorporates disciplines such as Colloid and Cycling in addition to Environmental chemistry.