The “Moving Green Infrastructure Forward” Project is a two-year stormwater monitoring project at Terminal 91, Port of Seattle. Using the Splash Boxx, a bioretention planter box used for stormwater management, the project compares the pollutant removal efficiency two bioretention soil mix designs: one with conventional sand/compost and another with volcanic sand/compost. Splash Boxx is recognized by the Washington Department of Ecology as equivalent to a bioretention facility, so the project was easily approved by the Port of Seattle. It was also designed consistent with City of Seattle guidelines for bioretention planter boxes.