Test learners' ability to apply principles of residential rain garden design to manage stormwater runoff, including site assessment (drainage, soil type, slope, setbacks), sizing and hydrologic calculations (runoff volume, capture area, ponding depth), soil/media and planting selection for infiltration and pollutant removal, inlet/outlet conveyance, maintenance considerations, and compliance with local regulations and climate; include one quantitative sizing calculation and one short written design justification.