As a geochemist interested in subsurface coupled processes, my primary research is in numerical simulation of thermal, hydrological, mechanical, and geochemical, (THMC) processes. Over 30 years experience developing numerical simulation codes that involve reactive transport, isotopic fractionation, multiphase fluid-heat flow, and geomechanics. Applications to Enhanced Geothermal Systems (EGS), geologic storage of high-level nuclear waste, mineral CO2 sequestration, fracture stimulation in unconventional hydrocarbon reservoirs, contaminant transport/bioremediation, magma differentiation, sedimentary basin evolution, and mid-ocean ridge hydrothermal systems. Involved in DOE EGS and geothermal projects including the Newberry Volcano EGS, Fallon FORGE EGS, and the Snake River Plain Play Fairway. Recent international collaborations include study of "Superhot" Geothermal Systems (Geothermica DEEPEN project). Co-developer of the TOUGHREACT and TReactMech codes licensed by LBNL and used worldwide. Currently a member of the DOE FORGE STAT (Scientific and Technical Analysis Team).