He has more than 30 years of experience in developing models for multicomponent reactive transport in porous media and applying them to topics in water-rock interaction, reactive contaminant transport, chemical weathering, isotopic exchange, and watershed modeling. Recent work has focused on modeling of geochemical transport and electrostatic effects in clay-rich rocks. He is the principal developer of the CrunchFlow software, which won an R&D100 Award in 2017 and was named an AGU Fellow in 2019. Research Interests High performance computing: HPC modeling of integrated terrestrial water and nutrients, subsurface fracture evolution Machine learning: Hybrid and reduced dimension/order models for watershed biogeochemical function Reactive transport modeling: Numerical modeling of pore scale processes, reactive contaminant transport, reactive transport in clays, chemical weathering and negative emissions of CO2 Mineral-water kinetics: Mineral dissolution and precipitation kinetics Biogeochemistry: Biogeochemical reactions in groundwater, estuaries, and oceans