What is a key characteristic of granular soils?

Granular soils are primarily composed of larger particles, such as sand and gravel, which contribute to their distinct characteristics. High permeability refers to the ability of water to flow through the soil, and granular soils possess this trait due to their larger particle sizes and the spaces between them. This allows for efficient drainage and water movement.

Low plasticity indicates that granular soils do not deform significantly when subjected to stress, as they lack the fine particles (like silt and clay) that typically impart plastic characteristics to a soil. As a result, when working with granular soils, one can expect them to maintain a relatively stable structure under load, contributing to their usefulness in construction and engineering applications.

In contrast, low permeability and high plasticity typically characterize fine-grained soils, which can retain water and exhibit greater deformation under stress. The presence of organic material, as mentioned in one of the other options, is more characteristic of organic soils, which are not defined as granular. Furthermore, high compressibility is typically associated with clays, not granular soils, which tend to resist compression due to their coarse nature. Thus, the defining traits of granular soils align perfectly with high permeability and low plasticity.