Which characteristic is not associated with a cohesionless soil?

Cohesionless soils are primarily characterized by their granular structure, which includes materials like sand and gravel. They exhibit high permeability, allowing water to flow easily through them due to the larger void spaces between the particles. Additionally, cohesionless soils lack adhesion, meaning that the particles do not stick together, which is a crucial factor in understanding their behavior under load and during drainage processes.

The identification of being "practically impermeable" is inaccurate for cohesionless soils. This characteristic is more aligned with cohesive soils, such as clay, which have fine particles and significant surface area that lead to low permeability. In contrast, cohesionless soils readily allow water to pass through, making them highly permeable instead of impervious. Hence, recognizing this distinction highlights why the answer focusing on "practically impermeable" is the correct selection, as it does not align with the fundamental traits of cohesionless soils.