Which type of soils has low infiltration rates and high runoff potential when thoroughly wetted?

The correct choice refers to Type D Hydrologic Group, which is characterized by soils that have very low infiltration rates and a high potential for runoff, particularly when they are saturated. These soils typically consist of clay and other materials that inhibit water absorption, leading to water pooling on the surface instead of seeping into the ground.

In contexts such as stormwater management and erosion control, understanding the hydrologic groups is crucial because Type D soils can significantly impact how water is managed after rainfall events. Their high runoff potential increases the risk of erosion and sedimentation in nearby water bodies, making it important to implement effective management practices to mitigate these issues.

In contrast, soils classified in Groups A, B, and C generally have better infiltration characteristics, enabling more rainwater to soak in rather than run off. This distinction highlights why Type D soils require specific attention in stormwater management strategies.