The founder has conducted hydrogeologic characterizations and implemented remedial systems to help industry solve complex site problems. In response to an unmet need, he sought to develop an innovative system for passively treating contaminated groundwater. The SubflowRx technology developed by our company uses an impervious barrier wall to divert contaminated groundwater toward treatment gates connected to the wall with vertical interlocks. A replaceable cartridge is placed in each gate and contains commercially available or customized PRMs for specific contaminants. When the PRMs are spent, the cartridge is removed and the PRMs are replaced. The modular technology harnesses natural groundwater gradients for in situ treatment of contaminants without external energy sources.