BMP design considerations for groundwater aquifer protection BMP design considerations for groundwater aquifer protection BMP Group Design Consideration Bioretention OK with proper caution for PSH Filtration OK with proper caution for PSH Open channels are OK, but polluted runoff must be adequately pretreated Infiltration Provide a 100-foot horizontal separation distance from wells and three-foot vertical distance from the water table No PSH runoff, unless treated by another practice, such as a filtering system Needed pre-treatment of all runoff except rooftop Stormwater Ponds May need liner if A soils or active karst are present. The CSW permit requires a liner in areas of active karst. Pre-treat PSH runoff Provide a separation distance from well or water table to BMP Constructed Stormwater Wetlands May need liner if A soils or active karst are present. The CSW permit requires a liner in areas of active karst. Pre-treat PSH runoff Provide a separation distance from well or water table to BMP